Massachusetts General Hospital

NIH Research Projects · FY 2025 · 2025-08

PROJECT SUMMARY/ABSTRACT Avoidant/restrictive food intake disorder (ARFID) is a severe and impairing eating disorder, affecting up to 4% of adults, characterized by food avoidance and restrictive eating motivated by sensory sensitivities, fear of aversive consequences of eating, and/or lack of interest in eating or food. Individuals with ARFID are at risk for serious health consequences. Cognitive-behavioral therapy for ARFID (CBT-AR) is a brief behavioral treatment for ARFID that has demonstrated evidence of feasibility, acceptability, and proof-of-concept. However, most individuals with ARFID do not have access to CBT-AR. Barriers to treatment access (e.g., cost, location) contribute to estimates that less than 25% of individuals with psychiatric disorders in need of treatment seek help. Further, the prevalence of psychiatric conditions worldwide—including ARFID—far exceeds the current capacity of mental health providers and services required. Digital mental health treatments (DMHTs), including mobile applications (“apps”), provide an efficacious, cost-effective, and scalable method for extending the reach of mental health care. Approximately 97% of American adults own a smartphone, further highlighting the utility of DMHTs as a promising avenue to increase access to healthcare resources. This proposal develops and tests a mobile app to deliver CBT-AR (mCBT-AR). I propose to: (a) utilize an iterative approach to developing mCBT- AR, implementing user-centered design principles; and (b) test the feasibility, acceptability, and proof-of-concept of mCBT-AR. My findings will fill a critical area in the necessity of a clinically effective, accessible, scalable, and inexpensive treatment for ARFID. In collaboration with my primary mentor (Dr. Thomas), co-mentors (Drs. Wilhelm and Fitzsimmons-Craft), and expert collaborators (Drs. Burton-Murray and Tabri, Mr. Landheim), I have developed a comprehensive training plan that will prepare me with the requisite skills and training needed to establish myself as a clinical investigator focused on increasing access to treatment for ARFID and other eating disorders through digital mental health treatments. My K23 training and career development goals are to: (1) gain expertise in digital mental health treatment development; (2) enhance my knowledge of symptom change and treatment response in ARFID; (3) establish skills in the design and analysis of brief interventions and randomized controlled trials; and (4) achieve independence in career development and the responsible conduct of research. Together, these goals will provide me with the necessary skills to transition to a career as an independent investigator, setting the stage for conducting R-level clinical trials. The proposed research will contribute to the development of a clinically accessible, scalable, inexpensive treatment for ARFID, a highly impairing disorder for which most individuals lack access to treatment. The mentored training will inform my preparation of a R01 grant application to conduct a larger randomized controlled trial of mCBT-AR, using a micro- randomized or adaptive design, to prepare for large-scale dissemination of the intervention to improve the lives of individuals living with ARFID.

NIH Research Projects · FY 2026 · 2025-08

Project Summary Candidate: Tristan Kooistra, MD is a physician-scientist at Massachusetts General Hospital (MGH) and Harvard Medical School (HMS). His post-doctoral research helped define pathologic cell circuits and interactions in airways of human subjects with asthma. Building on that work, this proposal investigates how epithelial-derived Notch signals promote maturation of airway macrophages. The short-term goals of this K08 award are to leverage his existing experience in innate immune signaling, type 2 immunity, and 3D imaging along with new cutting-edge research skills to address the role of Notch activation in airway macrophages and how this influences allergic responses. Dr. Kooistra’s long-term goal is to lead an independent research program investigating the role of airway macrophages in inflammatory airway diseases. Training Activities: Dr. Kooistra will perform the work outlined in this proposal at MGH mentored by Dr. Benjamin Medoff, an experienced mentor and expert in lung immunology. Drs. Eric Schmidt, Thorsten Mempel, Alexandra-Chloe Villani, and Carla Kim will serve on his advisory committee to provide further expertise in intravital microscopy, ‘omics’ methods, 3D co-culture modeling, and mechanisms of pulmonary inflammation. Dr. Kooistra will also complete didactic courses in immunology, biostatistics, and systems biology research and will take advantage of the collaborative and rich intellectual environment at MGH and HMS. Research: Asthma is a common disease resulting from the pathologic activation of multiple cell types within the conducting airways and is frequently driven by allergic inflammation to environmental antigens. Identification of immune regulatory pathways driven by cell-cell interactions in the airway mucosa can identify novel therapeutic targets. Our preliminary data establishes that airway epithelial basal stem cells supply tonic Notch activation signals to adjacent intraepithelial airway macrophages (IAMs) necessary to maintain their MHC-II expression. Moreover, depletion of IAMs or blockade of basal cell Notch signals results in reduced allergic airway inflammation. We hypothesize that Notch signaling from airway epithelial basal stem cells to IAMs determines IAM activation state and antigen-presenting capabilities to influence downstream T cell activation. To test this hypothesis, in Aim 1 we will determine how Notch activation influences IAM functional maturation at homeostasis using transgenic mouse modeling and single-cell RNA sequencing. In Aim 2 we will characterize the role of IAM Notch activation in the development of allergic airway inflammation using intravital microscopy and mouse modeling of asthma. We will leverage 3D airway co- cultures of human airway macrophages to extend these findings into human tissues. By combining murine models and primary human co-cultures this proposal will provide mechanistic insight into airway immunity with relevance to asthma as well as critical training for Dr. Kooistra’s development as a successful “bench-to- bedside” physician-scientist.

NIH Research Projects · FY 2026 · 2025-08

PROJECT SUMMARY/ABSTRACT At present, the diagnoses of many rare disease patients remain unsolved and the effects of rare variants in common diseases remains unclear. Further, the phenotypic effects of most high-impact mutations are unknown. Accurate methods to interpret genetic variants would enhance many aspects of biomedical research, including genome-wide association studies and functional studies, as well as clinical diagnostics of rare disease patients. In my laboratory, we build tools, methods, and resources to interpret genetic variation that are applicable in clinical practice and human disease research. Beginning with predicted loss-of-function variants, we have built a widely used annotation tool, LOFTEE, that is highly specific in identifying variants triggering nonsense- mediated decay. I have aggregated massive datasets of human genomes and exomes (gnomAD) to build the largest variant frequency maps released to the public, for clinical laboratories and researchers interpreting disease variation. Finally, I have performed massive-scale common and rare variant association analysis on thousands of phenotypes using mixed models to describe the most robust estimates of variant-phenotype associations, powering gene discovery for common diseases. Using state-of-the-art computational methods, this research program will improve the interpretation of variants in the human genome, improving current annotation methods for predicted loss-of-function, missense, and non-coding mutations, incorporating information from genetic reference data as well as biobanks with genome and disease/phenotype data. My research program will build a framework for assessing function for many classes of deleterious variants by integrating frequency data from diverse populations into deep learning frameworks. Finally, this project will integrate rare variant association data into deep learning models to identify loss-of-function-like missense variants. In this way, my research program will improve interpretation of genetic variants found in patients and large cohorts and biobanks, improving clinical genetic practice and human disease research.

NIH Research Projects · FY 2025 · 2025-08

Abstract The long-term objective of the Network of Excellence in Neuroscience Clinical Trials (NeuroNEXT) initiative is to efficiently translate advances in neuroscience into treatments for adults and children with neurological disorders through partnerships with government, academia, private foundations, and industry. The goal of this proposal is to establish and operate a Gene Therapy Consortium (GTC) that provides expert advice on clinical trials of gene therapies for ultra-rare adult and pediatric disorders conducted within NeuroNEXT. The GTC will consist of members with expertise in gene-based and gene-targeted therapies, ultra-rare and rare diseases, and clinical trial planning and execution, with particular emphasis on first-in-human or first-in-disease trials, small clinical trials, and adaptive trial designs. The GTC will be organized and managed by the NeuroNEXT Clinical Coordination Center (CCC) and will provide advice as requested for gene therapy proposals. The GTC members will support investigators applying to NeuroNEXT in all phases starting at the conception and planning phases and continuing for funded proposals through implementation, analysis and reporting for gene therapy trials within NeuroNEXT. Ultra-rare diseases affect less than or equal to 6,000 people. Many rare diseases, including ultra-rare diseases, have no FDA-approved therapeutic available and have an identified genetic origin. The NINDS supports gene- based therapy research through the Ultra-Rare Gene-based Therapy (URGenT) program. NINDS announced that they will expand the URGenT program to support the conduct of gene-based therapy clinical trials for ultra rare neurological diseases. Gene therapy proposals will be submitted to the NINDS using the URGenT program synopsis form. NeuroNEXT will serve as a clinical trial network for the conduct of early clinical trials of gene therapy for ultra- rare pediatric and adult neurological disorders. NeuroNEXT is currently comprised of 13 clinical sites, a Clinical Coordinating Center (CCC), and a Data Coordinating Center (DCC). A central goal of NeuroNEXT is to facilitate, from initial conception through final analysis, high-quality early-phase clinical trials and biomarker multisite studies with clear go/no-go decisions by providing efficient methodological, organizational, statistical, and logistical support. Aim 1 is to establish a collaborative and accessible Gene Therapy Consortium (GTC) with members with diverse expertise to support investigators in developing and conducting gene-based and gene- targeted therapies trials within NeuroNEXT. Aim 2 is to establish and implement an efficient process for gene therapy proposals to move from concept to design, implementation, analysis and reporting, in collaboration with the NINDS NeuroNEXT program officials and the NeuroNEXT Data Coordination Center (DCC).

NIH Research Projects · FY 2025 · 2025-08

ABSTRACT To earn the confidence of the scientific community, regulatory authorities, and, ultimately, our patients that xenotransplantation deserves to be systematically evaluated in humans, it is essential to demonstrate consistent long-term, life-supporting xenograft survival in a preclinical model. Although we have accomplished over one year of life-supporting survival in nonhuman primates (NHPs) using kidney xenografts with knockout (KO) of genes encoding three major carbohydrate xenoantigens (GalT, b4GalNT2 and CMAH KO, triple knock-out, TKO) and multiple additional human transgenes, thrombotic microangiopathy (TMA) and antibody-mediated rejection (AMR) remain the primary, prevalent causes of the TKO-based multi-gene edited (multi-GE) kidney and also heart and lung xenograft loss. We will test four working hypotheses regarding the reason for these preclinical and, in the case of heart xenografts, clinical failures. First, strong evidence implicates that knocking out the CMAH gene in TKO (but not DKO) swine unveils the expression of a ‘4th antigen’ that is the target of innate immunity in NHP but is irrelevant in human recipients. We will evaluate the contribution of the CMAH gene KO to pathogenic immune injury occurring in TKO organ xenografts by comparing the performance, histology, and molecular profile of kidneys, hearts, and lungs from 10-GE TKO to those from 9-GE DKO pig. We expect results using DKO-based 9-GE pig organs will enable the design of IND-qualifying organ xenograft trials for one or more organs. Second, based on compelling in vitro, ex vivo, and in vivo evidence that NK cells contribute significantly to heart, kidney, and lung xenograft injury, we will test the hypothesis that activation of NK cells will be inhibited by HLA-E expression on pig endothelium, which will attenuate inflammation and injury both in the xenograft and systemically in the recipient. Third, we will optimize the immunosuppressive regimen for kidney, heart, and lung xenografts. Finally, we will evaluate complement inhibition, CD11b blockade, donor macrophage depletion, and ischemia minimization as strategies tailored to each organ with the general objective of effectively modulating inflammation in the graft and organ xenograft recipient. The hypotheses, aims, and experimental approaches are harmonized between each Project and supported by Administrative, Pathology Mechanistic, Infectious Disease, and Swine Production Cores, which together will facilitate a coordinated effort to understand and overcome the remaining barriers to the clinical application of kidney heart, and lung xenografts. To our knowledge, MGH is the only center in the world capable of performing comprehensive comparative studies of kidney, heart, and lung xenotransplantation in preclinical models. We anticipate that together, these highly interactive projects will generate one or more safe and effective protocols ready for clinical trial by the end of the funding period. If successful, these studies would impact the entire field of transplantation.

NIH Research Projects · FY 2025 · 2025-08

Project Summary/Abstract Malaria remains a significant threat to global public health, causing over 600,000 deaths in 2022 alone, predominantly among African children under the age of five. Improving vaccines and implementing long-acting immune-based therapies to prevent transmission are critical to reduce malaria incidence and support global elimination efforts. Our team, and others in the field, have now identified panels of highly potent human antibodies against the pre-erythrocytic circumsporozoite protein of Plasmodium falciparum (PfCSP). The most potent of these anti-PfCSP antibodies (CIS43) shows over 85% protective efficacy in controlled human challenge studies and field trials. Deep molecular characterization of protective antibody candidates highlighted certain epitopes associated with improved antibody affinity and potency, which will be required for clinical malaria interventions. However, additional antibody potency improvements are still needed for broad deployment against P. falciparum, and the molecular mechanisms for protective antibodies against CSP of the second most significant human malaria species, Plasmodium vivax (Pv), are not well understood. Elucidating the functional molecular profiles of protective antibodies against Pf and PvCSP, particularly the relationships between affinity, targeted epitopes, and in vivo protection, is crucial to design effective, potent, and long-lasting vaccines and immunotherapies. This R01 research project builds directly on our previously published work improving antibody potency against PfCSP, and will analyze the molecular composition of protective antibody responses against both Pf and PvCSP. In particular, our goal is to identify new antibody variants with additional 5-fold or greater improvement on previous CIS43 and L9 variants to support broad medical use, and to understand the mechanisms that support exquisite protective potency for anti-malarial antibodies targeting sporozoites. In Aims 1 and 2, we will apply our validated yeast display and directed evolution platform to engineer anti-PfCSP antibodies for enhanced affinity and in vivo protection, with detailed characterization of the mechanisms behind potency improvements. We will focus on antibody lineage variants targeting the PfCSP junctional epitope (CIS43) and minor repeat (L9), which have already been validated as highly protective targets in human clinical trials. We will study the relationship between increased affinity and protective potency, with a focus on manipulating multi-epitope affinities across the highly similar CSP peptide repeat regions. In Aim 3, we will extend these approaches for multidimensional immune mapping of anti-malarial antibody repertoires elicited by recent exposure to Pv in Brazilian adults. We will identify the genetic, functional, and structural features of naturally elicited protective antibodies against PvCSP, and other sporozoite protein targets, that will guide new potential intervention mechanisms for vaccines against Pv. Successful completion of this R01 study will deepen our understanding of antibody-based malaria immunity to guide vaccine design and provide potent antibody drug candidates to help address the global burden of malaria.

NIH Research Projects · FY 2025 · 2025-08

PROJECT SUMMARY/ABSTRACT Hemifacial spasm (HFS) is a chronic neuromuscular disorder characterized by involuntary facial muscle contractions, typically affecting one side of the face. It significantly impairs the quality of life of patients by causing social embarrassment, functional blindness, and psychological distress. The current treatments for HFS, such as Botulinum neurotoxin Type A (BoNT/A) injections and microvascular decompression (MVD) surgery, provide symptom relief but do not address the underlying pathophysiological mechanisms, resulting in recurring symptoms for many patients. One of the primary challenges in advancing the understanding of HFS is the lack of an animal model that accurately replicates the clinical features of the disorder. Evidence suggests that hyperactivity of the facial nerve due to demyelination is associated with HFS. However, no existing rodent model has successfully imitated the spontaneous and involuntary nature of facial muscle contractions seen in HFS patients. This proposal aims to develop a novel rodent model of HFS using lysophosphatidic acid (LPA)-induced demyelination of the facial nerve roots, closely replicating the clinical manifestations of HFS. We hypothesize that demyelination of the facial nerve root at the root entry/exit zone (REZ) leads to hyperactivity of the facial nucleus, which drives HFS-like behavior in mice. Preliminary data strongly support this hypothesis, demonstrating that LPA injection into the facial nerve roots leads to robust HFS-like behavior, including asymmetrical eyelid twitching, whisker pad twitching with lip pulling, ear retraction, and forced eyelid closure. Additionally, electromyography (EMG) revealed increased burst activity in the facial muscles, and microelectrode array (MEA) recordings confirmed heightened activity in the facial nucleus of LPA-injected mice. To rigorously validate the facial spasm behavior and investigate the neural mechanisms underlying HFS, we propose three specific aims: Aim 1: Validate the HFS rodent model by employing DeepLabCut machine learning to accurately quantify facial muscle dynamics and assess facial spasm behavior with high precision. Aim 2: Assess the dynamics of cholinergic neurons in the facial nucleus using a viral strategy and intravital calcium imaging in Chat- Cre mice following facial nerve root demyelination. Aim 3: Investigate the effects of optogenetic and chemogenetic manipulation of facial nucleus activity on HFS-like behavior, determining whether modulating neuronal hyperactivity can alleviate the neuromuscular disorder. This approach will provide mechanistic insights into the role of the facial nucleus in HFS and identify potential therapeutic targets. Collectively, this project aims to validate a rodent model of HFS, elucidate the underlying neural mechanisms, and pave the way for the development of novel therapeutic strategies targeting the neural substrate involved in HFS. The insights gained from this study could significantly impact the treatment of HFS and contribute to improving HFS patient outcomes.

NIH Research Projects · FY 2025 · 2025-08

Project Summary Regulated cell death is essential for immune defense, development, and maintaining tissue homeostasis. While apoptosis removes damaged cells without causing inflammation, lytic cell death pathways such as pyroptosis and necroptosis may lead to excessive inflammation, contributing to chronic diseases and autoimmunity. Recent discoveries suggest that metabolism not only fuels cellular functions but also actively regulates the decision between survival and cell death. This project aims to explore how metabolic pathways control the transition between life and death, particularly focusing on comparing the lytic cell death program pyroptosis to the non-lytic cell death program apoptosis. Our research will investigate key metabolic regulators that influence cell death executioners that control membrane lysis including gasdermin D (GSDMD) and NINJ1. We will employ cutting-edge genetic and synthetic biology approaches, including forward and reverse genetics with CRISPR/Cas9, metabolic profiling, and engineered cell models, to uncover how metabolic signals determine whether cells commit to viability, pyroptosis, or apoptosis. Our work will also explore how metabolites released during cell death communicate with neighboring immune cells, shaping inflammatory responses and immune activation in vaccination, local infection, and systemic sepsis. By mapping the metabolic checkpoints that dictate cell fate, we aim to identify new therapeutic targets for modulating cell death and inflammation. These mechanisms will inform precision treatments to prevent excessive inflammation in autoimmune diseases, enhance immune responses in infections, and overcome chemotherapy resistance in cancer. The integration of synthetic biology, genetics, and chemical biology makes this a highly innovative and interdisciplinary project with significant implications for foundational research and human health. Upon completion, we expect to provide new strategies to control cell death and improve therapies for conditions where dysregulated cell death plays a pivotal role.

NIH Research Projects · FY 2025 · 2025-08

PROJECT SUMMARY / ABSTRACT This proposal presents a five-year research and career development plan focused on establishing Acanthamoeba castellanii—the third leading cause of infectious blindness and a cause of fatal brain infections—as a modern model parasite for studying infectious disease biology, comparative metabolism, and mitochondrial molecular biology, specifically by defining its mitochondrial proteins and pathways. The candidate, Jonathan Stefely, MD, PhD, completed clinical pathology training at Massachusetts General Hospital (MGH) and is now a postdoctoral researcher under the mentorship of Dr. Vamsi Mootha at MGH. Dr. Mootha is a pioneer in mitochondrial biology, genetics, and biochemistry, and has trained 80 scientists, including 29 postdoctoral scientists that now hold independent scientific leadership positions. The proposed project builds on Dr. Stefely’s previous research experience in biochemistry, now extending this work into unstudied areas of parasitology through an innovative and robust collaboration with local expert parasitology advisors, facilitated by his primary mentor, Dr. Mootha. Protozoan parasites span diverse branches of eukaryotic biology and contain strikingly diverse mitochondria, which are a proven anti-parasite drug target. Yet, most parasite mitochondrial biochemistry remains undefined. A central thesis of this proposal is that a systematic characterization of unique Acanthamoeba mitochondrial biochemistry that is not conserved in humans will unlock both new biology and new drug targets. In preliminary work with a team of collaborators at MGH, the Broad Institute, and Boston University, Dr. Stefely completely re-annotated the nuclear genome of Acanthamoeba castellanii and generated a high-quality draft of a new mitochondrial proteome inventory. Here, Dr. Stefely proposes to finalize and validate this Acanthamoeba “MitoCarta” (Aim 1) and to characterize select parasite mitochondrial proteins and pathways that were uncovered through his work, starting with an atypical branched electron transport chain (Aim 2) and novel proteins that function on mitochondrial DNA (mtDNA) (Aim 3). These three independent aims will build new knowledge of mitochondria, electron transport chains, mtDNA molecular biology, and potential anti-parasite drug targets. This mentored career development project will provide new training and expertise in parasitology, mitochondrial physiology, anoxic biology, and molecular biology—robustly supported by an exceptional group of mentors, advisors, collaborators, and unique resources at MGH, the Broad Institute, and Boston University. This project will also enable Dr. Stefely’s transition to independence with a focus on using the new Acanthamoeba genome annotation and MitoCarta to turn Acanthamoeba into a first-class model parasite for providing fundamental insights into the biology of protozoan parasites in clinical pathology.

NIH Research Projects · FY 2025 · 2025-08

PROJECT SUMMARY/ABSTRACT The rapidly growing population of >1 million children with medical complexity (CMC) confers 40% of pediatric healthcare costs, yet this calculation does not account for most of their intensive care. Parents and other family caregivers provide 24/7 care with minimal assistance and no breaks. As medical innovation enables CMC to live longer, parents’ constant work of care over decades jeopardizes their physical and mental health, their capacity to safely care for their children, and thus, the parent workforce on which the U.S. healthcare system depends. CMC parents report that respite – short-term direct care allowing caregivers a break – is critical to their well- being and to sustaining caregiving over time. Despite this, most CMC parents lack access to respite. To date, predictors and patterns of respite access nationally remain unknown, and there have been no rigorous intervention studies targeting improved access. Augmenting respite access for this stigmatized, understudied population is an urgent child health research priority. In my two-center, qualitative study of CMC parent respite experiences, parents reported no bandwidth to pursue respite care and trust only other parents to navigate resources. In response, I co-designed the first parent-to-parent peer navigation intervention to improve respite access. RECHArge (Navigating REspite REsources for parents of CHildren with medical complexity to improve Access) trains and employs CMC parent navigators to empower and guide CMC parents in accessing respite services. The proposed five-year research plan aligns with key NICHD research priorities to pursue three Specific Aims: (1) co-design and iteratively refine the RECHArge navigator training curriculum and corresponding intervention manual, (2) pilot test RECHArge to evaluate feasibility/acceptability and explore preliminary effects on respite access and parent/family well-being at two Massachusetts-based sites, and (3) identify predictors and patterns of respite access among CMC parents nationally with a focus on social determinants of health (SDOH). As an M.D.-Ph.D. investigator with training in pediatric palliative care, complex care, and anthropology, I am uniquely positioned to conduct the proposed study. Nonetheless, I need new skills for a career in intervention science. My four Training Aims fill important gaps in my knowledge and experience to prepare me to transition to career independence: (1) user-centered curriculum design, (2) RCT design and conduct, (3) social determinants of health measurement and analysis, and (4) pediatric palliative care leadership. I aspire to become an independent physician-investigator at the intersection of pediatric palliative care and pediatric complex care. Successful completion of the proposed research and training aims will prepare me to develop a multi-site, R01-funded efficacy trial. Accordingly, this project is the essential next step toward my long-term career goal of building an independent research program to improve well-being and quality of life for CMC parents and thus quality of care for the children to whom they dedicate their lives.

NIH Research Projects · FY 2025 · 2025-08

Project Summary/Abstract Blood gas analysis plays a crucial role in the care of preterm and critically-ill infants in the Neonatal Intensive Care Unit (NICU). Premature infants have immature lungs frequently requiring prolonged mechanical ventilation that can lead to a host of challenges necessitating constant monitoring of blood oxygen and carbon dioxide levels. Neonates in the NICU often experience significant life-threatening illnesses that affect the lungs, heart, brain, and gut that require constant monitoring and vigilance by NICU physicians and nurses. Arterial blood gas (ABG) measurements are the gold standard for detecting and managing these conditions and is the only method for quantifying blood oxygen specifically, but sampling blood from neonates is challenging. Repeated vascular access via stab puncture is impractical, necessitating arterial line placement for continuous access. However, the vessels of these infants are both tiny and fragile and the motion of neonates can lead to arterial lines becoming pulled or dislodged. Indwelling blood gas catheters exist and can be placed in the larger arteries, including the umbilical artery, but these systems carry the potential for tissue and nerve damage, malperfusion, and trauma to the gut. Problematically, while frequent ABGs are needed to monitor serious conditions - up to two or three times per hour - neonates have limited blood supply such that critically-ill infants regularly reach the threshold for blood transfusion, which carries additional risks. While transcutaneous devices have been developed with the goal of measuring blood gas levels, current devices require significant heating of the skin up to 44°C. As these high temperatures lead to skin burning and damage, these monitors are often either cycled, resulting in infrequent measurements, or operated at lower temperatures, resulting in poor agreement with ABG readings. There is an urgent need for new tools to improve the frequency, accuracy, and safety of blood gas measurements in the NICU. The proposed program leverages highly-sensitive physiologic sensors developed at the Wellman Center for Photomedicine to create and validate Versatile, Instantaneous Tracking of ABG Levels (VITAL) sensors for com- pletely non-invasive, safe, accurate, and high-frequency blood gas analysis. Aim 1 will design, implement, and test small, self-contained, wireless, and battery-operated devices that adhere to the skin for continuous neonatal blood gas readings without the need for heating or blood draw. This device will be tested in preclinical piglet mod- els, where medical gas and ventilation challenges will enable side-by-side comparison of VITAL sensor results with ABG values. Aim 2 will translate these devices to a first-in-human study in the NICU, where VITAL sensors will be directly bench-marked against ABG readings in preterm and critically-ill infants. Neonates from a full range of gestational ages, extremely premature to term, will be included in the study to validate VITAL sensors across physiological parameters including neonate size, skin thickness, ventilation, temperature, and disease status. The goal will be to validate the developed devices and methodology so that this promising technology can be rapidly translated to point-of-care technologies for NICU patients in the near future.

NIH Research Projects · FY 2025 · 2025-08

PROJECT SUMMARY/ABSTRACT Macrophages are a highly dynamic population capable of modulating stem/progenitor cells during early development and in regeneration. A general role for immune cells in mediating the inflammatory milieu has long been appreciated, but more recent efforts have uncovered more direct cell-cell communication between macrophages and stem cells which regulate their quiescence, migration, proliferation, and differentiation. Improvements in clonal lineage analysis, single cell sequencing, and live imaging have facilitated discovery of transient macrophage-stem cell interactions with long-term consequences. Through selective amplification of individual stem/progenitor cells and phagocytosis of others, macrophages can effectively ‘quality assure’ overall tissue function and architecture during development and regeneration. The overall goals of my lab are to dissect the molecular signals which mark stem/progenitor cells for macrophage interaction at the transcriptional, proteomic, and metabolic levels, to compare regulatory cues delivered by macrophages in development and regeneration across multiple tissue types, and to uncover the mechanisms which lead to elimination of some stem cells and expansion of others. Understanding this biology will allow for the development of therapeutic approaches using macrophages to specifically eliminate disease-causing cells while also providing supportive cues to others. Over the next five years, my group will develop a technical approach that combines molecular profiling, clonal analysis, live imaging, and zebrafish genetics to study stem cell quality assurance by macrophages. We will utilize sophisticated genetic approaches to study the presentation of the ‘eat me’ signal Calreticulin which mediate macrophage-stem cell interactions in developing and regenerating blood, skeletal muscle, and spinal cord. We will compare the influence of macrophages on the architecture of these organ systems through clonal barcoding, single cell ATAC-sequencing, and live- imaging approaches to identify the shared functional and genomic features at play. Finally, we will utilize cutting edge single cell proteomics and CRISPR mutagenesis to discover pathways which modulate macrophage engulfment of stem/progenitor cells in development and regeneration of the blood and spinal cord. Together these approaches will advance a mechanistic understanding of macrophages as key modulators of stem cells in development and regeneration. We are broadly interested in questions concerning cell-cell competition, non-cell autonomous stem cell regulation, and regeneration versus scarring. By leveraging the advantages of zebrafish, we will address these questions by studying the interface between macrophages and stem/progenitor cells across multiple organ systems. The long-term goal of this project is to develop strategies for both targeted elimination of specific cells – such as in scar formation or cancer – and targeted protection or expansion of other cells – such as after injury or transplantation.

NIH Research Projects · FY 2025 · 2025-08

Hallucinogens are a heterogeneous group of substances that cause visual and auditory hallucinations, profound changes in one’s perception of time and space, and changes in mood. Many hallucinogens are also referred to as psychedelics. In recent years, there has been a massive resurgence of interest in hallucinogens within clinical research and popular culture, as clinical trials suggest that many hallucinogens hold promise for treating a range of mental disorders (e.g., depression, anxiety). Rates of hallucinogen use have risen sharply in recent years, particularly for young adults, for whom rates of hallucinogen use have nearly doubled in just three years (2018-2021). Moreover, evidence suggests that individuals are increasingly self-medicating using hallucinogens due to their reported mental benefits. Yet, a major gap in our knowledge is that we lack information about how naturalistic (i.e., real-world, non-clinical) hallucinogen use impacts mental wellbeing. Clinical trials provide very limited information about the real-world health impacts of these substances, and existing research on naturalistic hallucinogen use is severely limited (e.g., cross-sectional studies). Furthermore, many hallucinogens can have adverse health consequences when used in non-clinical settings (e.g., extreme anxiety, paranoia). In light of rising rates of use, there is an urgent need for rigorous studies to fill the aforementioned knowledge gap. Thus, the proposed DP5 project will assess the impact of naturalistic hallucinogen use on internalizing symptoms (e.g., depressive affect) in young adults; I will focus on young adults given that rates of use have increased disproportionately quickly within this age group. For my project, I will use data from Monitoring the Future (MTF), an NIH-funded longitudinal study on substance use and health in American youth (N = 100,000+). Further, I will use g-methods, a well-established set of statistical approaches that are designed to facilitate causal inference with observational data. Aim 1a will use inverse probability weighted marginal structural models (IPW-MSMs) to assess the impact of hallucinogens (e.g., LSD, MDMA, ketamine, “other hallucinogen use”) on internalizing symptoms (depressive affect, self-esteem, self-derogation, loneliness). Aim 1b will further assess the impacts of hallucinogen use on internalizing symptoms using a second g-method: structural nested mean models (SNMMs) with g-estimation. I hypothesize that hallucinogen use will have negative effects on internalizing outcomes; this hypothesis is not ethical to test in the context of a randomized trial, warranting this observational approach. Aim 2 will assess how individual characteristics (age, marital status, income, education, religious importance, rurality) impact the link between hallucinogen use and internalizing symptoms; I will use SNMMs with g-estimation for this aim. In sum, this project stands to provide valuable information about the real-world health impacts of hallucinogen use, identify individual-level factors that are closely linked to the possible negative effects of hallucinogens, inform public policy, and set the stage for future investigations in this area.

NIH Research Projects · FY 2025 · 2025-08

Project Summary/Abstract Despite recent advances in cancer therapy, cancer remains the second leading cause of death in the United States. The field of cancer immunotherapy has evolved to meet this challenge, but there is an ongoing need for treating metastatic and treatment-resistant solid tumors, particularly those of lung, breast, prostate, and colorectal origin. Cellular immunotherapies, such as chimeric antigen receptor (CAR) T-cell therapy, have shown success in treating blood cancers. However, they remain ineffective against solid tumors, and are often fraught with inherent toxicities such as cytokine release syndrome and attack of healthy tissues. In light of these challenges, this proposal aims to harness natural killer (NK) cells, which have broad anti-tumor activity and a superior safety profile, to generate CAR NK-cell therapy as an effective immunotherapy against solid tumors. CAR NK-cell therapy has recently shown remarkable success against blood cancers but remains challenging for use in solid tumors. The tumor microenvironment employs immune-evasive mechanisms to subvert NK-cell killing and limits their infiltration and survival. Our research proposal will address these obstacles by leveraging high-throughput, sequencing-based functional screens and innovative synthetic biology approaches that will shed light on fundamental NK-cell biology and enhance CAR NK-cell infiltration and killing of solid tumors. We will implement a genome-wide CRISPR screen in primary human NK cells to identify negative regulators (‘innate immune checkpoints’) of NK-cell cytotoxicity. Subsequently, we will identify homing and survival signals in tumor- infiltrating immune cells by mining single-cell RNA-sequencing databases. We will then introduce these genes into NK cells to enhance their infiltration and survival in in-vitro and in-vivo models of the tumor microenvironment. Finally, we will perform a high-throughput CARpool screen to simultaneously assess hundreds of NK cell-tailored CARs designed with native NK cell-receptor signaling machinery to maximize CAR NK-cell functioning. In summary, this proposed research introduces several innovative approaches to study fundamental NK-cell biology and engineer NK-cell based immunotherapies against solid tumors. Our project is poised to uncover new targets in NK cells for 'innate immune checkpoint blockade' as well as create the next-generation of CAR NK- cell therapy for treating metastatic and treatment-resistant cancers. Ultimately, we will establish a pipeline of technologies that can be applied to many cancer types in order to broaden the scope of immunotherapies against cancer and transform patient care to mitigate the devastating impact of this disease.

NIH Research Projects · FY 2025 · 2025-08

Improving CAR-T cell therapy in metastatic breast cancers by reprogramming obesity-aggravated tumor microenvironment via physical activity Breast cancer (BC) is the leading cause of cancer-associated death in women worldwide. Metastatic BC (mBC) is the most common cause of death in BC patients. Chimeric antigen receptor (CAR)-T cell immunotherapy has revolutionized hematologic cancer therapy. However, CAR-T cell therapy is largely ineffective in solid tumors, including BCs, due to hostile tumor microenvironment (TME) such as abnormal vasculature, hypoxia, and immunosuppression. We and others have shown that exercise training (ExTr) can normalize tumor vasculature, TME, and anti-tumor immunity in primary tumors. However, the effect of ExTr on neither CAR-T cells nor metastatic tumors is known. Here, we propose to evaluate whether physical activity improves the delivery and function of CAR-T cells via vascular normalization, alleviation of hypoxia and immunosuppression, and improvement of response to CAR-T cells in mBCs. To this end, we will use well-controlled preclinical mBC animal models—spontaneous BC lung metastasis following primary BC removal—and moderate-intensity exercise (60% of maximal incremental exercise, optimal based on our recent studies). We will determine how ExTr affects tumor vasculature and immune TME, immune cell profile, and progression of mBCs. We will also assess the effect of ExTr on transcriptional profiles and protein expression in innate and adaptive immune cells, stromal cells, and tumor cells in BC lung metastases (Aim 1a). Based on previous studies in primary tumors, we expect to find an increase in the number and function of cytotoxic T lymphocytes (CD8+ T cells) in mBCs by moderate ExTr. Then, we will assess the effect of ExTr on CAR-T cell infiltration and function in mBCs. We chose TnMUC1 as an initial target for CAR-T cells as it is highly and selectively expressed in all BC subtypes, and TnMUC1-CAR-T cells are being tested in ongoing clinical trials. We will transduce TnMUC1 in murine BC cells and test the delivery and function of TnMUC1-CAR-T cells in TnMUC1+ mBC models (Aim 1b). Next, we will determine if ExTr potentiates CAR-T cell therapy for mBCs. We will assess how ExTr, in combination with TnMUC1-CAR-T cells, affects lung mBC progression and survival (Aim 1c). Obesity is a significant confounding factor for many types of tumors, including BCs. It aggravates abnormal TME, interferes with immune cell recruitment and function, and promotes tumor progression, metastasis, and treatment resistance. Hence, we will determine if physical activity can alleviate obesity-aggravated immunosuppressive TME and enhance anti-tumor immune cells (Aim 2a). Finally, we will evaluate if ExTr can improve TnMUC1-CAR-T cell delivery and function and the response to CAR-T cell therapy in mBCs under obesity (Aim 2b). In summary, this is a high-impact project with multiple strengths. The proposed approach is conceptually novel and will reshape physical activity in cancer patients from general fitness to supportive therapeutic intervention. Hence, the applicability of the proposed approach would be immense. With the successful accomplishment of this study, we can rapidly transform ExTr-CAR-T cell immunotherapy, making it more effective in mBCs, even in obesity.

NIH Research Projects · FY 2025 · 2025-08

PROJECT SUMMARY The overarching goal of this proposal is to investigate the role of the FGFR1 signaling pathway in the intersection between reproduction and metabolism. Even though reproduction and metabolism have been intricately linked, the underlying mechanisms that govern this intersection are not clearly understood. One pathway that could bridge those two domains is the fibroblast growth factor receptor 1 (FGFR1) signaling pathway. Regarding reproduction, FGFR1 is crucial for the development of neurons that secrete Gonadotropin Releasing Hormone (GnRH), a hormone that heralds the onset of human sexual maturation, with rare deleterious heterozygous FGFR1 variants leading to pubertal failure. Regarding metabolism, attenuation of FGFR1 signaling leads to diabetes in mice and insulin resistance in humans. Activation of the FGFR1 signaling pathway improves metabolic health in animal models and humans. One potential explanation of how the suppression/activation of the same receptor leads to such disparate phenotypes is through the action of the different FGF ligands and co- receptors. The Applicant has hypothesized that while FGFR1 is essential for both reproduction and metabolism, distinct FGF ligands and their interactions with specific co-receptors will impart phenotypic specificity: the paracrine FGF8 ligand and HS6ST1 co-receptor will be specific for reproduction, while the endocrine FGF21 ligand and KLB co-receptor will be specific for metabolism. To test this hypothesis, the PI will: (i) conduct a unique Recall-by-Genotype (RbG) study and in-depth neuroendocrine (Aim 1) and metabolic (Aim 2) phenotyping in humans carrying rare deleterious FGF-related genetic variants; and (ii) examine the FGF ligand specific effect on FGFR1 signaling in cells related to reproduction and metabolism. This application outlines a comprehensive 5-year training program designed to foster the Applicant’s mentored career development in translational research. Completion of this project will serve as an ideal training vehicle for the Applicant’s training in neuroendocrine and metabolic investigation. To achieve this goal, she has selected mentors with complementary expertise: Dr. Stephanie Seminara [mentor, Chief of the Reproductive Endocrine Unit at Massachusetts General Hospital (MGH)] is a world expert in reproductive neuroendocrine physiology and human genetics of reproductive disorders; Dr. Steven Grinspoon (co-mentor), Chief of the Metabolic Unit, MGH, is a renowned expert in studies of hormonal function, nutrient trafficking, and the metabolic consequences of fat redistribution in a broad number of disease conditions. This award will effectively prepare the Applicant to launch a successful translational research career, with an emphasis on intersection between reproduction and metabolism, a key NICHD research priority area. The Applicant's career development plan involves rigorous coursework and seminars, hands-on experience, and guidance from advisors with diverse scientific backgrounds. In summary, the expertise gained during this award will form the basis for the Applicant's independent academic transdisciplinary career as a physician-scientist.

NIH Research Projects · FY 2025 · 2025-08

PROJECT SUMMARY/ABSTRACT Pseudomonas aeruginosa is a ubiquitous, opportunistic bacterial pathogen adept at developing antimicrobial resistance and capable of colonizing a variety of host tissue sites to manifest disease. The immunocompromised lung, damaged skin from burn or injury, or scratched cornea represent vulnerable sites where P. aeruginosa infection establishes to cause significant pathology. P. aeruginosa exhibit both planktonic and biofilm lifestyles in the course of infection. Host cells are infiltrated by individual bacteria damaging affected tissue while communities of bacteria emerge in extracellular space as biofilms. These colonization tactics create formidable targets that challenge the defensive capabilities of individual neutrophils recruited as part of the innate immune response. In turn, neutrophils have evolved a strategy of working together as a population to synergize their collective arsenals against large target pathogenic threats that lie beyond the capacity of individual neutrophils to phagocytose and clear. This strategy reflects an emergent property of the collective called neutrophil swarming whereby individual neutrophils coordinate to surround a target (an area of infection or damage) so that the swarm can isolate and neutralize the threat. A greater understanding of the cellular and molecular mechanisms of neutrophil swarming has tremendous potential to reveal novel anti-infective therapeutic strategies with improved efficiency geared toward harnessing the power of the swarm to eradicate intractable infections. This proposal is timely as multidrug resistant strains of P. aeruginosa have been on the rise in recent years and pose an increasingly alarming burden to healthcare providers. We unveil herein a novel ex vivo model of neutrophil swarming against a laboratory cultivated large bacterial target. The bacterial target consists of P. aeruginosa combined with agar to create beads of imbedded bacteria growing as microcolonies on the bead surface. We demonstrate that neutrophils rapidly swarm in response to these large bacterial targets and the swarm can temporarily restrict bacterial growth. We seek to leverage this new model to identify P. aeruginosa and neutrophil factors that drive this multifaceted innate immune response. Our data suggests that elements of the bacterial type three secretion system (T3SS) play a central role from the pathogen perspective. Additionally, we will explore contributions of the neutrophil swarm amplifying agent, leukotriene B4, and mechanisms by which it is biosynthesized by a neutrophil community in the context of swarm development. Overall, we contend that our approach contributes a new tool for investigators to use when seeking to understand cellular and molecular mechanisms of neutrophil swarming. In leveraging this tool, we aim to add to this knowledge base by executing of our proposed mechanistic studies focused on both host and pathogenic factors. Results of our investigations can serve as foundational toward development of novel anti-infective strategies that bolster host innate immune responses rather than targeting the infecting organism, which may reduce development of drug resistance and provide efficacy to a variety of infectious organisms with limited treatment options that cause disease in humans.

NIH Research Projects · FY 2025 · 2025-08

PROJECT SUMMARY Acute Respiratory Distress Syndrome (ARDS) is a life-threatening condition characterized by widespread pulmonary inflammation that leads to lung injury. In severe cases, the mortality rate can exceed 40%. Imaging provides a topographical distribution of perfusion, which is typically heterogeneous in ARDS. This information is crucial for developing treatment strategies. However, assessing lung perfusion in ARDS is challenging due to a lack of suitable bedside measuring tools. Electrical Impedance Tomography (EIT) is a relatively new modality that shows promise as a bedside tool for measuring subtle changes in lung perfusion, thereby eliminating the need to transport these critically ill patients to offsite imaging facilities. The current EIT acquisition, involving hypertonic contrast administered via a central venous line during a 30-second breath-hold, is feasible only for sedated patients who can tolerate interruptions to their respiratory cycle and have a central line in place. However, central venous catheterization has associated risks, prompting a shift toward the use of peripheral intravenous catheters. Furthermore, recent ARDS definitions include non-mechanically ventilated patients, underscoring an urgent need for EIT methods that do not require the cessation of spontaneous breathing. Currently, acquisition methods that bypass these limitations remain undeveloped. Our study aims to advance EIT application by adapting it for use during regular breathing cycles in both fixed- rate and spontaneous (Aim 1), and utilizing peripheral venous injections (Aim 2), thereby eliminating the need for induced apnea and central line placement. We also seek to optimize image acquisition and strengthen post- analysis techniques by leveraging successful strategies from more established dynamic contrast-enhanced (DCE) MRI and CT methods and applying them to EIT. This will be achieved through animal experiments using equal numbers of male and female Yorkshire pigs under healthy and lung-injured conditions, as well as observational studies in 20 ARDS patients with pneumonia. Key methodological innovations include the development of a model-based filter to separate the enhancement trace from contrast injections and decouple it from cyclic respiratory patterns, facilitating the capture of perfusion data without interrupting normal respiration. We plan to explore deconvolution methods and compare traditional first-pass kinetic models to assess their resilience to lower SNR caused by peripheral injections and hypoperfusion due to injury. Additionally, we will investigate analysis beyond the first-pass kinetics to address interstitial pathology. The success of this study could broaden the application of perfusion measurement, streamline the process, and facilitate safer, more frequent, and precise bedside evaluations of lung perfusion in ARDS patients, ultimately enhancing patient care and clinical outcomes.

NIH Research Projects · FY 2025 · 2025-08

PROJECT SUMMARY AND ABSTRACT Brain maturation involves intricate and concurrent cellular changes throughout childhood and adolescence. With the capability to noninvasively track whole brain development, MRI holds the promise to enhance our understanding of normative brain maturation and facilitate the identification of neurodevelopmental disorders. However, the commonly used measures from structural and diffusion MRI, such as cortical thickness or fractional anisotropy, lack the sensitivity and specificity required to differentiate between biological processes such as synaptic pruning and myelination. These processes influence the diffusion MRI signal, not just through morphological changes in cellular organization but also via physical properties like T2/T2*, affected by alterations in chemical composition such as iron concentration. Current neuroimaging measures are confounded by these multifaceted influences, at the expense of validity and interpretability in brain maturation studies. A central hypothesis of this proposal is that these confounding influences can be disentangled through the next generation combined diffusion-relaxometry microstructure imaging and myelin specific imaging, providing increased statistical power in detecting developmental changes spatiotemporally. To test the hypothesis, we will develop acquisition and analysis methods for combined diffusion-relaxometry microstructure imaging and myelin water imaging that can be applied to neurodevelopmental populations. The goal is to collectively provide a unique fingerprint of neurodevelopment by disentangling the developmental changes in cell body density, neurite density, cell size, subcellular T2/T2*, and myelination. The K99 phase will supplement the applicant’s expertise in microstructural imaging methods, by providing training in developmental neuroscience, with a focus on understanding biological factors relevant to microstructural development; statistical approaches to analyzing age effects on brain-area dependent microstructure; and study design and administration for adolescent neuroimaging studies. This training will position the applicant well for collecting pilot datasets and validating the proposed methods during the R00 phase. Leveraging the latest advances in human MRI scanners, this project will undertake significant innovations in imaging acquisition, microstructural modeling, and quantitative analysis. The objectives include: i) Develop practical, highly accelerated acquisition protocols for detailed microstructure mapping with cutting-edge MRI sequences and commercially available ultra-strong diffusion gradients; ii) Develop machine learning tools for unbiased and efficient estimation of microstructural parameters at the individual level; iii) Develop a cross-subject, registration-free microstructural analysis pipeline that is robust to morphological differences across age groups; iv) Collect pilot datasets from a developmental cohort and assess the power of the developed microstructural fingerprint to detect cellular changes. We will share the rich datasets and novel insights of brain maturation through this project. We will disseminate the optimized imaging protocols and computational tools to the scientific community, with the aim of benefitting a wider range of applications.

NIH Research Projects · FY 2025 · 2025-08

PROJECT SUMMARY This application requests funding to purchase a clinical grade NVision Polaris™ C13 polarizer. This instrument allows hyperpolarization of C13 substrates, providing more than a 10,000-fold increase in MRI signal. Metabolic imaging with hyperpolarized C13 substrates allows objective measures of the injected substrate and its metabolic products to track key metabolic pathways in real-time. The potential of C13 metabolic imaging has been demonstrated in 30+ clinical trials of prostate, breast, cervical and brain cancer patients worldwide. Hyperpolarized C13 MRI is safe, and more than 800 patients have been scanned. In cancer imaging, C13 MRI can allow more accurate detection of tumors, disease progression, and treatment response. There are also non- cancer applications where metabolic derangement may serve as an early or precise biomarker, for example alteration in neurodegenerative disorders such as Alzheimer’s or liver dysfunction. Installation of this clinical C13 polarizer at our institution will be revolutionary for several reasons. First, it will be FDA-approved for human use and MGH would be the only site in New England to have this capability. Second, this instrument can be used on our PET/MR system, which would enable combination C13 MRI-PET imaging. Third, this polarizer uses a different technique to achieve hyperpolarization known as parahydrogen induced polarization, with the resulting advantage where a clinical-grade sample can be produced every 5-10 minutes—a 1/10th of the time in comparison to prior-generation systems—allowing for seamless integration into a clinical imaging workflow and for whole-body imaging studies. Lastly, there are several laboratories in the Boston area that have conducted extensive preclinical research with hyperpolarized C13 metabolic imaging in the brain, kidneys, liver, and pancreas, and this system would finally allow translation of many of these studies into the clinical realm. In addition, there are other investigators in the area who are conducting clinical studies on neuroinflammation, drug response, prostatic inflammation, and neurodegenerative diseases that would benefit from having a C13 polarizer to provide new in vivo data on tumor or tissue metabolism. The proposed C13 polarizer will be located within the Massachusetts General Hospital, at the center of the Mass General Brigham Cancer Center. The system will be run in partnership with the Martinos Center, a renowned molecular imaging center known for cutting-edge MR research, including a preclinical C13 metabolic imaging program, with additional expertise in MEG, PET, Nano-particle MRI and Optical Imaging. We look forward to sharing this instrument with researchers and collaborators across the Greater Boston area and throughout New England.

NIH Research Projects · FY 2025 · 2025-08

ABSTRACT The cerebrospinal fluid (CSF) system is an understudied area of research in the context of autism spectrum disorder (ASD) despite its known role in development. For example, the delivery of growth factors through CSF circulation and the CSF pressure generated by normal CSF production are both essential for embryonic brain development. Recent lines of evidence demonstrate that components involved in the CSF system, namely the perivascular spaces (PVS) and choroid plexus, are altered in individuals with ASD. The PVS is the site where metabolic waste is cleared from the brain by means of the CSF while the choroid plexus produces CSF and regulates the composition of CSF. Enlarged PVS is a marker of altered glymphatic CSF clearance and has been observed in individuals with ASD. A diffusion magnetic resonance imaging (MRI) metric that measures diffusion along the PVS (DTI-ALPS) and is often found to be lower in conditions with impaired glymphatic function is lower in children with ASD. In terms of the choroid plexus, initial reports show enlarged volume and altered texture in the choroid plexus in individuals with ASD. Preliminary data from our group shows that the choroid plexus volume is significantly larger in adults with ASD compared to matched controls. Additionally, larger choroid plexus was associated with more severe ASD symptoms. Despite being closely related, no study has investigated the relationship between PVS measures (PVS volume, DTI-ALPS index) and choroid plexus volume in individuals with ASD to date. Intriguingly, our preliminary data show that lower DTI-ALPS index (i.e., found in conditions with impaired glymphatic function) is associated with larger choroid plexus volume in male adults with ASD. This project will leverage data from a publicly available dataset, the Autism Brain Imaging Data Exchange II, to assess PVS measures (PVS volume, DTI-ALPS index) and choroid plexus volume in boys with ASD and controls, aged 5-12. By focusing on a cohort of children, we can learn if alterations are present at an early stage. We will be able to evaluate 1) whether PVS measures or choroid plexus volume are altered in boys with ASD compared to matched controls, 2) whether there are any associations between PVS measures and choroid plexus volume in ASD and controls, and 3) whether PVS measures and choroid plexus volume are associated with ASD symptom severity.

NSF Awards · FY 2025 · 2025-08

The immune system is designed to protect our bodies from harmful invaders like viruses and bacteria. To do this, one type of immune cell—called a T cell—must be trained to recognize and attack these threats while avoiding the body’s own healthy tissues. This training process is quite good at eliminating T cells that could attack the body—known as self-reactive T cells. However, it is not perfect, and some self-reactive T cells still make it into circulation. Why this system allows these potentially harmful cells to remain has long puzzled scientists. The traditional view holds that self-reactive T cells are dangerous mistakes—usually kept under control, but capable of causing autoimmune disease if regulation fails. This project explores a new idea: that the immune system may tolerate self-reactive T cells for a reason—that, when properly regulated, these cells might help keep tissues healthy. The investigators findings suggest this could be especially true in the uterus, which goes through regular cycles of breakdown and repair during the reproductive years. In this context, self-reactive T cells appear to support tissue remodeling, helping to maintain reproductive health. To further explore this idea, the project combines immunology and systems biology, using advanced imaging, mathematical approaches, and genetic tools to study how self-reactive T cells behave in the uterus. The research should reshape how scientists think about autoimmunity and fertility—and potentially lead to new ways to treat reproductive disorders like endometriosis or infertility. This award was co-funded by the Developmental Systems Cluster. A subset of highly self-reactive T cells persists in the body despite central tolerance mechanisms designed to eliminate them. While these cells are generally considered dangerous, this project presents a new hypothesis: that their persistence reflects a purposeful feature of the immune system—enabling self-reactive T cells, when properly regulated, to support normal tissue physiology. The murine uterus provides an ideal system for evaluating this concept, as its endometrial lining undergoes rapid, cyclical breakdown and regeneration during the estrous cycle—dynamics only partially explained by hormonal signals. The preliminary data reveal that conventional CD4+ T cells accumulate in the endometrium in an oscillatory manner, in phase with the estrous cycle, and become locally activated by endometrial antigens seemingly derived from self proteins. Disruption of these cells perturbs endometrial turnover, suggesting a physiological role for self-reactive T cells in driving endometrial tissue remodeling. To further test this hypothesis, the project will pursue three independent aims: 1) define the antigen specificity and activation triggers of endometrial T cells across the estrous cycle, 2) identify the molecular and cellular mechanisms regulating their accumulation, dynamics, and effector functions, and 3) assess how their dysregulation impacts reproductive hormone dynamics and fertility outcomes. These aims will be addressed through an interdisciplinary approach that combines quantitative in situ multiplexed imaging, mathematical modeling, and genetic perturbations. This research is tightly integrated with an educational initiative to train interdisciplinary scientists at the interface of immunology and systems biology through a new course and PhD program at MIT. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NIH Research Projects · FY 2025 · 2025-08

PROJECT SUMMARY This proposal centers on the study of endogenous dendritic cell (DC) function in glioblastoma (GBM). GBM remains an extremely challenging cancer to treat, and clinical outcomes remain poor. However, despite the seismic influence of immunotherapy in cancer, there remain no FDA approved immunotherapies for GBM. There are several reasons that underlie the difficulty in extending immune-based treatments to the central nervous system (CNS). GBM harbors few T cells and is considered “non-inflamed”, a myriad of immunosuppressive features has been identified in patients, there is a paucity of DC in the brain parenchyma, and the CNS is also immunologically specialized due to the presence of site-specific elements not seen elsewhere—e.g., lack of lymph nodes, presence of dural lymphatics, and the blood-brain barrier, among others. In this context, how and where endogenous DC drive T cell activation and expansion remains a huge gap in our understanding of how immune responses to GBM can develop and, ultimately, be accelerated therapeutically. As compelling as exogenously administered DC therapies have been in our field, here we focus on understanding how the endogenous DC-driven immune response to GBM develops. We have assembled a team with Dr. Petti that brings diverse expertise to this work. We have previously shown that conventional dendritic cell type 1 (cDC1) are required for endogenous neoantigen specific responses to the murine GL261 GBM model and are necessary for anti-PD-L1 mediated treatment of GL261-bearing mice. Moreover, cDC1 are able to acquire antigen and traffic to the cervical lymphatics and are also present in the dural layer of the meninges. Finally, we observed that cDC infiltrate human glioblastoma and acquire metabolites from 5-ALA fluorescence guided surgery. In Aim 1, we will deepen our mechanistic understanding of cDC1-mediated T cell priming by exploring the CCR7 and STING dependence in T cell responses to GBM. We will also examine the relative contributions of cDC1 and cDC2 in brain tumor immunity using cDC-selective mouse models and, finally, investigate the basis of cDC1- dependence in anti-PD-L1 mediated GBM immunotherapy. In Aim 2, we will study when and where cDC1 acquire tumor-derived antigen and investigate where antigen-carrying cDC1 can be found in specialized dural structures and present antigen. We will extend these observations by testing the exciting possibility that accelerating antigen flux through dural lymphangiogenesis can augment anti-GBM T cell responses. Finally, in Aim 3, we will translate our observations to patients by creating a cell atlas from enriched GBM infiltrating DC and testing whether DC carrying metabolites from 5-ALA exhibit enhanced antigen presenting capacity. We will then study DC in situ using cutting edge spatial transcriptomics in tumors, dura, choroid plexus, and cervical lymph nodes in patients recently deceased from GBM through the unique rapid autopsy program at MGH. Together, these Aims will reveal novel mechanistic insights into how cDC drive T cell responses to GBM in preclinical models and patients that may illuminate compelling new avenues for immunotherapeutic strategies.

NIH Research Projects · FY 2025 · 2025-08

Our team proposes to develop a facial-expressions-based machine learning algorithm named autoBPS to predict the electronic Behavioral Pain Score (eBPS), a digital endpoint for continuous monitoring of pain using facial expressions in the ICU environment (COMPANION). In the UG3 Phase, we will conduct a pilot-phase single-center observational prospective cohort study (N = 48) to develop the autoBPS machine learning algorithm prototype at MGH. We will perform exploratory analyses to establish clinical associations between facial expressions, EEG biosignals and pain, and to conduct analytical and clinical validations in accordance with the FDA regulatory requirements. In the UH3 Phase, we will further scale up to a multi-center prospective cohort study (N = 216) to expand, externally validate, and extend the autoBPS algorithm at three academic hospitals of MGH, BWH, and BIDMC. We will continue to expand the autoBPS model with newly collected BWH/MGH data and externally validate its performance on BIDMC set-aside data. We will extend and examine the utility of autoBPS for evaluating treatment effects as ICU clinical trial endpoints. Lastly, we will examine its generalizability on non-ventilated patient cohorts and perform bias minimization techniques for model enhancement. We expect that our autoBPS algorithm will provide an automated, resource-sparing, and reliable assistant tool for continuous pain monitoring in the ICU. Such a tool will help decrease patient suffering, reduce clinician workload, and facilitate scalable automated pain assessment in clinical research.

NIH Research Projects · FY 2025 · 2025-08

Project Summary: The goal of this Mentored Career Development Award is to facilitate the candidate’s transition to independence as a translational oncologist using deep learning (DL) to study therapeutic resistance in solid tumor oncology. The Candidate is an oncologist at the Massachusetts General Hospital (MGH) with a background in cancer genomics and functional imaging. This K08 Award will allow the Candidate to build upon his burgeoning experience in supervised DL. However, as an MD-only scientist, the Candidate has reached the limits of what he can accomplish as a self-taught programmer. Therefore, to further develop his DL skillsets, the Candidate will be mentored by world leaders in DL (John Guttag; Jayashree Kalpathy-Cramer). This computational expertise is complemented by the Candidate’s scientific advisors: Drs. Gerstner, Iafrate, and Rosen, who are experts in early-phase clinical trials, molecular pathology, and radiology applications of DL, respectively. With this mentorship team, the Candidate will be uniquely positioned to succeed as a physician- scientist using DL to analyze and integrate clinically acquired data to develop personalized treatment paradigms for cancer patients. This Award will be further supported by the unparalleled institutional support and environment offered by the MGH, Broad Institute of Harvard / MIT, and Martinos Center for Biomedical Imaging. Here, the Candidate seeks to build upon a seminal study which demonstrated intracranial efficacy of checkpoint inhibition (ICI) for brain metastases of diverse tumor types (Brastianos & Kim et al., Nature Med, 2023). Despite functional imaging and comprehensive genomic analysis, the Candidate and other groups have not identified a robust predictive biomarker for ICI response. Therefore, given the ability of DL to extract and combine complementary information across high-dimensional modalities, the objective of this Award is to use DL to integrate radiology, histopathology (H&E), and clinico-genomic data to predict ICI response in BM. We will use a multi-national dataset comprised of brain MRI, H&E from resected BM tissues, and clinico-genomic data from 2100 BM patients treated with ICI. The first aim will develop a DL model, using pre-treatment brain MRI, to predict ICI efficacy in BM. The second aim will develop a separate DL model, using H&E, to predict ICI efficacy in BM. The third aim will develop a multi-modal fusion model, integrating MRI, H&E, and clinico-genomic data, to predict ICI efficacy. Performance of each model (MRI-based model vs. H&E-based model vs. multi- modal model) will be compared to current clinical biomarkers (e.g., PD-L1 expression) to determine the most accurate technique. In addition, the Candidate will experiment with state-of-the-art pretraining and data augmentation strategies to maximize model generalizability. These results will lay the groundwork to design a future R01-funded effort to accrue prospectively collected data to validate our multimodal fusion strategy. Through identifying optimal methods for multimodal data fusion, our work supports and highlights NIBIB’s mission of using machine intelligence tools in the clinic to augment clinical decision making.