University Of California, San Diego

NIH Research Projects · FY 2026 · 2023-02

PROJECT SUMMARY Decades of research using laboratory mice and rats have revealed mechanisms of human development and disease. It is highly likely that rodents have provided critical supporting data for clinical trials of every pharmaceutical or therapeutic approach currently used to improve human health. There are, however, limitations to the utility of mice and rats to understand and model complex genetic problems (e.g. Alzheimer's, heart disease, and diabetes) due to the rare probability of inheriting desired alleles at four or more loci and the small litter size compared to offspring of other traditional model species. The cost, time, and number of animals needed to model complex genetic traits would be reduced by an approach to increase the probability one of the two alleles at multiple loci will be transmitted to the next generation. CRISPR/Cas9-mediated gene conversion, which is feasible in mice, can perhaps accomplish exactly this goal by copying genetic information from a donor to a recipient allele in the germline. Briefly, this occurs by germline-restricted expression of genetically encoded Cas9 and a guide RNA (gRNA) that targets only the recipient and not the donor allele. If the double strand break in the recipient allele is repaired by interchromosomal homology directed repair, the recipient allele is replaced by the donor allele. CRISPR/Cas9- mediated gene conversion therefore changes the genotype of the cell from heterozygous to homozygous and ensures any resulting sperm or egg will transmit only the donor allele. The proposed objectives will build on proof-of-feasibility to improve the efficiency of CRISPR/Cas9 mediated gene conversion in the female and male mouse germline and to test the efficiency of gene conversion at two loci in the same cell. Previous work suggests a high level of Cas9 expression timed to initiate during early meiosis I is necessary for efficient gene conversion in both sexes. Aim1 of this proposal seeks to apply this knowledge to develop and test three BAC transgenic drivers of Cas9 expression using regulatory sequences of the meiotic genes Tex12, Prdm9, and Rad51ap2. To date, CRISPR/Cas9-mediated gene conversion has been assessed at one locus – Tyrosinase. Aim 2 seeks to quantify the efficiency of gene conversion at two additional loci individually and of two loci together in the same cell. Mathematical models predict the efficiency of multi-locus gene conversion, but empirical evidence is required to determine whether the actual efficiency follows a `multiplicative' or `coordinated' probability. The outcomes of this research are critical to maximize the utility and future biological impact of CRISPR/Cas9-mediated gene conversion approaches to model and solve a variety of genetically complex challenges to human health.

NIH Research Projects · FY 2025 · 2023-02

PROJECT SUMMARY Disease modifying anti-rheumatic drugs (DMARDs) have greatly improved the treatment of inflammatory joint disease but cause generalized immunosuppression and increase the risk of serious infections and cancer. The pathogenic inflammation, a hallmark of autoimmune arthritis, can largely be ascribed to a deficiency in regulatory immune function. There is a critical need for anti-arthritic agents that can operate without impairing the immune system, which could also be combined with current DMARDs in patients who struggle to achieve durable remission. Towards this goal, the objective of the grant application is to validate a new strategy of intra-articularly (IA) drug delivery of an immunomodulatory agent that could promote durable disease remission in autoimmune arthritis without causing generalized suppression of immunity. Our agent leverages pre-existing regulatory T cells (Treg), widely recognized as the primary suppressors of autoreactive T cells, to promote a disease modifying anti-inflammatory effect. Recognizing that Treg are often insufficiently recruited to the inflamed joints, display abnormal levels of inflammation-induced instability and loss of function, our approach achieves localized expansion and stabilization of joint Treg and results in reduced inflammation and systemic disease modification in affected joints of arthritic mice without causing generalized immunosuppression. Here, we will validate our approach as a therapeutic option for inflammatory arthritis. In Aim 1 we will optimize our approach such that it durably enhances the magnitude and function of Treg for modulating inflammation. In Aim 2, we will systematically validate the mechanism of action of our agent and demonstrate the enhancement of disease-relevant Treg without suppressing non-specific T cell responses. In Aim 3, we will assess the adjunctive potential of our approach with a widely used first-line DMARD to reduce disease severity in mice that show partial DMARD responsiveness and assess whether the agent is effective in the ex-vivo enhancement of Treg isolated from DMARD-treated arthritis patients. Overall, these studies will advance our long-term goal of developing our approach to correct pathogenic immune dysregulation in autoimmune disorders affecting the joint and other tissues, arising from insufficient Treg function.

NIH Research Projects · FY 2026 · 2023-02

PROJECT SUMMARY Pulmonary disorders like respiratory infections are one of the leading causes of death in the world and result in millions of deaths annually. The immune system’s initial line of defense against lung disease are mononuclear phagocytes called alveolar macrophages (AMs). These immune sentinels play an important role during homeostasis by clearing foreign pathogens like microbes and toxins in the airways of the lungs via phagocytosis. Additionally, AMs have an active role in pulmonary tissue repair by conducting efferocytosis, a type of phagocytosis that specifically removes apoptotic cells. By preventing the release of proinflammatory cytokines while secreting anti-inflammatory signals during efferocytosis, AMs contribute to barrier immunity and exhibit an immunosuppressive phenotype. Studies have also demonstrated that AMs communicate intercellularly with epithelial and T cells to prevent unneeded proinflammatory responses. Research into AM development has shown that tissue-specific cytokines derived from the lungs, such as GM-CSF and TGF-β, are required for the differentiation of monocytes into mature AMs. This plastic response to the pulmonary microenvironment is regulated by epigenetic modifications, such as DNA methylation and transcription factor recruitment. Notably, aberrant AM development and function have been implicated in the progression of multiple lung malignancies, such as influenza infections, chronic obstructive pulmonary disease, and some types of lung cancer. Furthermore, dysfunctional AMs can contribute to the increased morbidity and mortality of elderly and immuno-compromised individuals. As such, this study’s long-term goal to enhance the understanding of epigenetic mechanisms governing AM development and function tightly aligns with NIH’s mission to prevent disease and improve human health. The key focus of this project aims to investigate the role of PBRM1, the defining subunit of the SWI/SNF family PBAF complex, in dictating the development and function of murine AMs. To elucidate the effects of PBRM1-deletion on AM development and phenotype, I plan to 1) determine the requirement for PBRM1 in AM development and self-renewal, 2) determine the role of PBRM1 in transcriptional and epigenetic programs of AMs by performing RNA-seq and ATAC-seq on PBRM1 WT and KO AMs to identify pathways and transcription factors which may be dependent on PBRM1, as well as overlapping this data with CUT&RUN data of PBRM1 and transcription factors known to drive AM development, such as PPARγ and PU.1.; and 3) determine the functional effects of myeloid-specific PBRM1 deletion during influenza infection. These studies will assess the epigenetic and transcriptional effects of PBRM1-loss in AMs and provide evidence for novel co-regulators of PBRM1. In the future, this research will serve to inform the development of targeted therapies of PBRM1-dependent processes affecting lung disease.

NIH Research Projects · FY 2026 · 2023-02

This new application represents a continuation of the California Primate Spinal Cord Research Consortium project on human embryonic stem cell (hESC) derived neural stem cell transplantation; our overarching goal is to understand both basic mechanisms of spinal cord organization and function in non-human primates, and to leverage these and other advances in developing translational human pro-regenerative therapies. We have made considerable progress in the last 5 years and now propose new specific aims that will directly bear on the potential of human neural stem cells (NSCs) to benefit human SCI. Aim 1: Examine Mechanisms Underlying Graft-Related Functional Improvement: Graft Silencing with Inhibitory DREADDs. Work in this aim will establish whether functional recovery observed in non-human primates after grafts of spinalized neural stem cells is related to graft activation of host neural circuits. This knowledge will be important for human translation. Aim 2: Determine Whether 4-AP Improves Anatomical and Functional Outcomes After Neural Stem Cell Grafts There is a vast literature supporting potentially beneficial effects of 4AP in SCI, and 4AP is approved for human use as a conduction-enhancing drug in multiple sclerosis. This aim will determine whether treatment with neural stem cell grafts plus 4AP improves anatomical and functional outcomes. Aim 3: Determine Whether PTEN/SOCS3 Inhibition Improves Host Corticospinal Regeneration and Functional Outcomes. Rodent studies indicate that functional benefits of neural stem cell grafts are mediated by formation of host-to-graft-to-host electrophysiological relays across sites of SCI. These relays require host axon regeneration into grafts. In humans, corticospinal axons are essential for voluntary movement. This aim will determine whether inactivation of PTEN/SOCS3 will enhance corticospinal axon regeneration and improve functional outcomes in primates.

NIH Research Projects · FY 2026 · 2023-02

PROJECT SUMMARY Medicine is currently undergoing a revolution, where viable gene therapies are being developed for multiple disorders, including diseases of the central nervous system (CNS). One of the obstacles that limits the use of gene therapy is the availability of safe and effective vectors for widespread delivery of genes. Due to its stable transgene expression, broad tropism, and modest immunogenicity, recombinant adeno-associated virus (rAAV) is the most widely used viral vector for human gene therapy. Almost 200 rAAV therapies have been completed or are currently in clinical trials, including two FDA-approved therapies for genetic diseases of the CNS. However, evidence is mounting that rAAV-based gene therapies are not without toxicity or significant risk, with several rAAV-related deaths and numerous adverse outcomes reported during the past three years alone. In a recent trial for Sanfilippo syndrome, 1 patient died and others demonstrated concerning MRI changes at rAAV injection sites within the brain, halting the study. Other rAAV trials have reported serious adverse effects ranging from thrombocytopenia to acute kidney failure to cardio-pulmonary insufficiency. While some of these adverse effects are thought to be caused by immune reactions to the AAV capsid or transgene, increasing evidence indicates that the rAAV genome, which contains two 145-base pair DNA segments named inverted terminal repeats (ITRs), is a major source of rAAV toxicity. While conducting fundamental experiments on learning and memory, we discovered that rAAV was toxic to dividing neural progenitor cells (NPCs) and immature neurons, completely ablating adult neurogenesis in the mouse hippocampus. Consistent with previous work, these experiments indicate that the AAV ITRs appear to be sufficient and necessary for this toxicity. Embarking on a new research direction, we will utilize our complimentary expertise in neuroscience, stem cell biology, and engineering to develop new methods for rAAV production and create the first rAAVs with engineered ITRs that are safer for human gene therapy. These new therapies will be particularly important in the treatment of neurodevelopmental and other diseases in children who have active proliferation of stem/progenitor cells, which are exquisitely sensitive to rAAV toxicity. In the current proposal we aim to: Aim 1. Determine which components of the ITR DNA sequence are required for toxicity in NPCs in vivo. Aim 2. Develop a cell-free synthetic rAAVs capable of packaging genomes with mutant ITRs. Aim 3. Engineer an rAAV that will rescue loss of function in a murine model of Rett syndrome while demonstrating less toxicity than conventional rAAVs.

NIH Research Projects · FY 2026 · 2023-02

PROJECT ABSTRACT This is an application for a K01 award for Dr. Alejandra Morlett Paredes, a postdoctoral fellow in the Neurosciences department at the University of California, San Diego (UCSD). Dr. Morlett Paredes is establishing herself as a young researcher conducting research to further understand Latino’s intentions to consent and participate in brain donation studies and those that include invasive procedures for Alzheimer’s Disease and Related Dementias (ADRD) research. This K01 award will provide Dr. Morlett Paredes with the support and time necessary to accomplish the following goals: (1) gain proficiency in community engagement and recruitment; (2) gain proficiency in mixed methods and survey research methodologies; (3) gain proficiency in neuropathology of dementias; and (4) to develop grantsmanship and professional skills. To achieve these goals, Dr. Morlett Paredes has assembled an expert mentoring team, including her primary mentor: Dr. Hector M. González (expertise in neuroscience) and co-mentoring team: Drs. Lisa Barnes and David X. Marquez (experts in community-based recruitment with underserved populations), Dr. Mark R. Luborsky (expert in mixed methods and survey development) and Dr. Anne Hiniker (expert in Alzheimer’s disease neuropathology and brain autopsy process). The goal of the proposed project is to develop a survey instrument and culturally-tailored educational material that will measure intention to consent and participate in brain donation studies for ADRD research among older and diverse Latinos. Dr. Morlett Paredes will achieve this goal through the following specific aims: Aim 1: (a) Develop and validate a new questionnaire, informed by the Organ Donation Model, to assess dimensions of older Latinos’ intent to participate in brain donation research amongst community based and UCSD ADRC participants; (b) Design culturally-tailored educational information through use of focus group techniques. Implement the new instrument developed in Aim 1a to pilot test the impact of these materials by comparing pre- and post-intervention scores on attitudes and intention to consent and participate in brain donation research using UCSD ADRC participants and older community-based Latinos from the San Diego area. Aim 2: Implement the new survey instrument in a large cohort of diverse older Latinos from the SOL-INCA to obtain information on attitudes and intention to participate in brain donation research. If validated, this study will be used to develop an R01 to enroll diverse Latinos in autopsy studies at ADRCs across the US proximal to 4 SOL-INCA Field Centers in Bronx, Chicago, Miami, and San Diego, beginning with the UCSD ADRC.

NIH Research Projects · FY 2026 · 2023-02

Synaptic dysfunction and neuritic dystrophy are prominent pathologic features of the prion- and Alzheimer’s disease-affected brain. Ubiquitinated protein inclusions are also commonly observed, providing strong evidence of impaired proteostatic pathways. Ubiquitination of cell membrane proteins and clearance through the ESCRT pathway (endosomal sorting complex required for transport) is critical to maintaining synaptic homeostasis. Here we will deeply investigate the ESCRT pathway contributions to disrupted synaptic homeostasis in prion disease. In prion-infected mice, we have found markedly reduced ESCRT-0 (an Hrs and STAM1 protein complex) and an enrichment of ubiquitinated proteins in synaptosomes. Strikingly, depleting neuronal Hrs in prion-infected mice shortened survival time and accelerated the degeneration of synapses, biochemically and structurally. Additionally, in a longitudinal study of the prion-infected hippocampus, we found an upregulation in the synaptic activity response gene, Arc/Arg3.1, and a chronic elevation in phosphorylated CaMKII and phosphorylated AMPA receptors, suggestive of enhanced and altered synapse function beginning in early disease. Our long-term goal is to decipher how prion and amyloid-β oligomers disrupt signaling pathways linked to the cellular prion protein, inducing proteostatic dysfunction and synaptic degeneration. Using electrophysiology, correlative light-electron microscopy, and proteomics on uninfected and prion-infected cultured neurons, we will first determine how Hrs expression impacts synapses, assessing activity, pre-and post-synaptic proteins, structure, and signaling. We will then test how distinct prion conformers impact the ESCRT pathway and neuronal signaling at glutamatergic synapses. Finally, we will investigate the contribution of glutamate receptor activity to prion spread and neurodegeneration. We will directly test how the findings in these genetically manipulated models compare to human prion-affected brain. These studies are the first to test how neuronal activity impacts prion dissemination, synaptic degeneration, and disease progression, and outcomes are expected to provide key insights into the deregulated synaptic signaling that drives neuron loss, thus revealing new therapeutic targets.

NIH Research Projects · FY 2026 · 2023-01

Project Summary/Abstract RNA viruses have had an immense impact on human health. SARS-CoV-2 is only the most recent of many RNA viral zoonoses, and, even disregarding pandemics, the health burden of endemic RNA viruses, particularly in vulnerable populations, is substantial. Epithelial cells, abundant and exposed at mucosal surfaces, are often the first to be infected by RNA viruses, and are therefore often the first cell type to detect and respond to viral infection. However, unlike circulating immune cells, their in vivo behaviors cannot be measured from blood draws, and their behavior ex vivo may poorly correlate with in vivo dynamics. Our long-term goal is to understand how epithelial cells coordinate anti-viral responses in a whole-animal setting. Our previous work demonstrated that the RIG-I-like receptor (RLR) DRH-1 in the nematode C. elegans activates an anti-viral transcriptional response in intestinal epithelial cells that we named the Intracellular Pathogen Response (IPR), which protects against infections by viruses and other intracellular pathogens. We found that DRH-1 responds to infection with Orsay virus–a single-stranded, positive-sense RNA virus that naturally infects C. elegans intestinal epithelial cells. The objective of this proposal is to determine where and how DRH-1 triggers resistance to Orsay virus infection, and investigate whether in C. elegans, which lacks identified homologs of interferons, there is a role for bystander cells in mounting an immune response. The central hypothesis is that upon Orsay virus infection, DRH-1 in intestinal epithelial cells detects viral replication and induces the IPR, signaling to neighboring cells through an as-yet undescribed pathway. The rationale is based on our genetic analysis of DRH-1 and its role in anti-viral responses, and our visualization of IPR gene expression and DRH-1 localization dynamics in the context of infection. Our work is innovative because we are pursuing the IPR, which shares similarity with the type-I interferon (IFN-I) response in humans, but excitingly, appears to signal through novel factors, as homologs of MAVS, IRF3, NFkB, TNF-alpha and IFN-I itself are absent from the C. elegans genome. We will test our hypothesis with three specific aims: Aim 1) Where and how does DRH-1/RLR promote anti-viral defense in C. elegans? Aim 2) What signaling pathway is activated downstream of DRH-1/RLR in C. elegans? Aim 3) Which host cells mount an anti-viral immune response in C. elegans? The expected outcomes are to establish the signaling cascade used by DRH-1/RLR to trigger the protective IPR immune response in intestinal epithelial cells of C. elegans, and to identify the components of a systemic defense system. The proposed research is significant, because it could lead to new treatments for infections by RNA viruses, as well as a better understanding of epithelial immune defense and inflammatory diseases.

NIH Research Projects · FY 2026 · 2023-01

PROJECT SUMMARY/ABSTRACT This proposal aims to elucidate how the bacterial metalloenzyme nitrogenase catalyzes the chemically difficult transformation of atmospheric dinitrogen into a bioavailable form, ammonia, and why/how it utilizes ATP hydrolysis to drive this reaction. Being the only enzyme responsible for reductive nitrogen fixation, nitrogenase sustains the agricultural/nutritional needs of ~40% of the human population. Aside from its global importance, nitrogenase is a unique model system with broad relevance to biological redox catalysis as well as ATP/GTP-dependent energy transduction processes, which are both central to proper cellular functioning and thus directly relevant to human health. Despite nearly five decades of extensive biochemical, biophysical, and structural characterization, the two most important questions about nitrogenase mechanism have not been answered in detail: a) Why and how ATP hydrolysis is ultimately utilized for the reduction of N2 or alternative substrates? b) What is the intimate mechanism of dinitrogen reduction on the nitrogenase active site metal cluster, FeMoco? The major experimental challenge in the investigations of nitrogenase arises from the fact that the catalytic activity of nitrogenase depends on continuous ATP turnover, which leads to a heterogeneous mixture of redox and nucleotide-bound states of nitrogenase that are difficult to distinguish from one another. To circumvent this challenge, we have initiated a research program in single-particle cryogenic electron microscopy (cryoEM) to structurally characterize dynamic states of nitrogenase at atomic resolution under enzymatic turnover conditions. Preliminary experiments have not only established the feasibility of this approach but also revealed unexpected structural features of nitrogenase which have fueled new mechanistic hypotheses. In the proposed project, we aim to build upon on these preliminary findings by a) mapping the ATP-driven conformational landscape of nitrogenase in unprecedented detail under catalytic turnover conditions and b) elucidating FeMoco structural dynamics and FeMoco-small molecule interactions in atomic resolution, while also c) contributing to the development of cutting-edge cryoEM methodologies for the structural interrogation of highly complex/dynamic protein assemblies and metallocofactors.

NIH Research Projects · FY 2026 · 2023-01

SUMMARY The leading human bacterial pathogen group A Streptococcus (GAS) causes over 700,000,000 cases of superficial disease such as pharyngitis and pyoderma each year but can also lead to serious invasive infections and autoimmune sequelae, which combine to make GAS one of top 10 causes of infection-associated deaths worldwide. The highest mortality burden of GAS disease is caused by rheumatic heart disease (RHD), which results from repeated bouts of acute rheumatic fever (ARF). It is difficult to overstate the urgent public health need for a safe and efficacious GAS vaccine for human use. A significant number of experimental GAS vaccines are backlogged in preclinical development, with questions around safety, global GAS strain coverage, potential for efficacy in humans (i.e. lack of animal efficacy model data that accurately reflects disease). We have recently demonstrated that choice of adjuvant plays a pivotal role in imparting protective efficacy for an experimental multi-component GAS subunit vaccine in both a murine invasive disease model and the non-human primate (NHP) model that closely recapitulates GAS pharyngitis, the primary target for vaccine protection. Moreover, these studies suggest that promoting immunity skewed towards Th1 may elicits optimal protection beyond that afforded by the standard Alum adjuvant formulation. Herein, our highly experienced team of scientists with an extensive track record of productive collaboration will expand this important line of investigation to deliver proof- of-concept of the impact of adjuvant on the efficacy of three leading experimental GAS vaccines: (1) a 30-valent N-terminal M protein vaccine (StreptAnova) from the University of Tennessee that has reached phase 1 human trials; (2) Vaxcyte VAX-AI from Vaxcyte, Inc. in collaboration with UC San Diego, a conjugate vaccine with modified group A carbohydrate conjugate, and GAS proteins SLO, SpyAD, SCPA; and (3) Combo#5 from the University of Queensland incorporating 5 conserved immunogenic GAS antigens: SLO, SCPA, SpyCEP, ADI, TF. The vaccines will be formulated with Alum or selected emulsion and liposome-based adjuvants, using four distinct mouse models (skin, intranasal, intraperitoneal and invasive disease). Protective efficacy, immune response, correlates of protection, and vaccine safety (cross reactivity to human heart tissue) will be assessed. Finally, protection afforded by three selected vaccine-adjuvant combinations will be assessed in the non-human primate model of GAS pharyngitis, which most closely mimics GAS primary infection of humans, and clinical scoring and vaccine safety parameters determined. To advance the entire GAS vaccine field, our head-to-head comparison of M protein and non-M protein GAS vaccines, in both select mouse models and the NHP pharyngitis model, will have broad implications. across the field. We will identify the most efficacious antigen and adjuvant formulations using the animal models we have developed. Adjuvants that we identify will be available for use with other GAS vaccines via the Vaccine Formulation Institute (Switzerland), a not-for-profit organization who help guide advancement of effective formulations toward human trials and commercial use.

NIH Research Projects · FY 2026 · 2023-01

Summary/Abstract Down Syndrome (DS) affects over 200,000 individuals in the United States and is the most common genetic cause of intellectual and developmental disabilities in children and young adults. Down Syndrome arises from an extra third copy of chromosome 21, encompassing over 200 genes, which leads to genome wide transcriptional disruption. The brain cell-type specific contribution to DS neurodevelopmental deficits and the interaction between cognitive and immune dysfunction in DS are poorly understood. DS has been difficult to model due to limitations in murine orthologs and inadequacies of in vitro systems in modeling complex cellular interactions. Microglial pathology has been identified in individuals with DS, but the extent to which microglial dystrophy contributes to neurodevelopmental deficits is unknown. There is increasing evidence for the impact of microglia on brain development and microglia have been suggested as a novel therapeutic target in DS. This proposal is built around the central hypothesis that trisomy 21 causes microglial dysfunction and thereby contributes to the pathogenesis of intellectual and developmental disability in DS. Motivated by our strong preliminary data that in vitro microglia exhibit altered gene expression and functional phenotypes in neurodegenerative diseases and psychiatric disorders, we developed novel organoid microglia cocultures and a chimeric human microglia mouse model, whereby 80% of microglia are human in origin. Here we apply innovative in vitro and in vivo methods to ascertain the contribution of human DS microglia in neurodevelopment, neuronal function, and cognition. The project goal is to test the hypothesis that isolated trisomy 21 in human microglia and microglia-cerebral organoid cocultures in vitro (Aim 1) and in a xenotransplantation model of human microglia in vivo (Aim 2) results in microglial pathology, neuropathological defects, and behavioral deficits. Delineating genome wide transcriptional disruption and genome wide reorganization will uncover DS associated transcriptional dysregulation and expand our knowledge of DS associated genes. The long-term goal is to generate and validate in vitro and in vivo DS microglial models that can be employed for drug screening and to generate preclinical data. A deeper understanding of the contribution and molecular regulation of microglia in DS will lay the groundwork to ultimately identify novel potential therapeutic targets to improve the outcomes for individuals with DS.

NIH Research Projects · FY 2026 · 2023-01

Abstract Hepatocellular death plays an essential role in the development of nonalcoholic steatohepatitis (NASH). The activity of the energy sensor AMP-activated kinase (AMPK) is repressed in NASH and nonalcoholic fatty liver disease (NAFLD). Recent studies from our laboratory demonstrate that AMPK normally phosphorylates the pro-apoptotic caspase-6 to inhibit its activation, keeping hepatocyte apoptosis in check. Steatosis-induced suppression of AMPK activity relieves this inhibition, rendering caspase-6 activated in both human and murine NASH. Activation of AMPK or inhibition of caspase-6, even after the onset of NASH, improves liver damage and fibrosis. Because caspase-6 is an attractive therapeutic target, we will develop high affinity and high specificity chemical inhibitors of caspase 6 for the treatment of NASH. We will pursue two series that are already well advanced, one that binds covalently to the enzyme with high affinity and specificity, and a second noncovalent series that stabilizes the inactive, zymogen state of caspase-6 and inhibits its activation. Selective inhibition of caspase-6 over other caspases has been difficult to achieve before now, but should be safe given the mild phenotype of caspase-6 knockout animals and patients with inactivating mutations. Using structure- based design, we will develop a clinical candidate based on affinity, specificity, ADME properties, bioavailability and in vivo activity in mouse models of NASH. We will also develop a biomarker for capsase-6 inhibition in vivo that will help guide future clinical trials. These efforts may lead to development of the first specific drug that directly attacks the pathogenic process underlying the development of human NASH.

NIH Research Projects · FY 2026 · 2023-01

Project Summary/Abstract Autoimmunity against neuronal receptors causes an array of diseases. Cys-loop receptors are a class of neuronal receptors targeted in autoimmune diseases including myasthenia gravis, autoimmune encephalitis, and autoimmune autonomic ganglionopathy. Myasthenia gravis is the longest studied; antibodies against the neuromuscular nicotinic acetylcholine receptor were described in 1974. Autoimmune autonomic ganglionopathy was first identified in 2000 as being associated with antibodies against the ganglionic nicotinic acetylcholine receptors. Most recently, autoimmune encephalitis was associated with antibodies against the related GABAA receptor. Mechanisms underlying autoimmune pathology are poorly understood but are often attributed to receptor cross-linking and internalization. However, other mechanisms that include direct inhibition of neurotransmission are increasingly reported. We have access to blood and cerebrospinal fluid from patients suffering from myasthenia gravis, autoimmune autonomic ganglionopathy, and autoimmune encephalitis. Here we propose to identify and clone autoimmune antibodies that target Cys-loop receptors. We will examine functional receptor inhibition by patient-derived antibodies using electrophysiology. We will produce antibody fragments to determine structures of the antibody-receptor complexes from different autoimmune diseases. These structures combined with functional interrogation will illuminate conserved and divergent mechanisms of autoimmune disease in this important protein superfamily. This work will lay the foundation for expansion to other targets of the Cys-loop receptor family and beyond.

NIH Research Projects · FY 2026 · 2023-01

PROJECT SUMMARY/ABSTRACT This proposal responds to RFA-MH-22-135. Non-disclosure of suicide ideation prior to attempt is normative and even more common in later life. Similarly, our preliminary data indicates lower inclusion of social contacts in suicide safety plans among at-risk older adults. Unfortunately, interventions to increase informal help seeking are ineffective to date. Therefore, major roadblocks exist in the interpersonal processes seen as essential to late-life suicide prevention, and new targets are needed for increasing help-seeking behavior. The purpose of this longitudinal observational project is to understand why older adults do not disclose suicide ideation or seek help from others amidst suicide crises. We focus on social cognitive abilities and biases, which influence how individuals perceive (or misperceive) others and have previously been associated with loneliness, suicidal ideation and behavior. The premise of this research is that social cognitive impairments impact the positive and negative valence systems involved in affiliation and the social structures that determine help seeking in suicide. Facilitating this research, our group has developed and validated a dyadic social affiliation task that objectively quantifies RDoC positive and negative valence systems involved in support seeking. This task enables evaluation of valence systems across multiple units of analysis, including behavior, self-report, facial affect and natural language processing. Measurement of these intrinsic processes will be integrated with quantification of extrinsic help-seeking opportunity, via structural social network assessment. A translational aspect of our proposed social network analyses is to augment network measurement with the social elements of suicide safety planning. In a longitudinal study, we will recruit a sample of diverse older adults from a variety of urgent, primary, and mental health care settings. Recruitment will be stratified by groups defined by current active suicide ideation, depressive symptoms without ideation or attempt histories, and healthy comparators. In Aim 1 of the study, we will compare groups on social cognition, positive and negative valence indicators from our social affiliation task, along with social network structure, including past help seeking and disclosure in the subgroup with current suicide ideation. In Aim 2, we will administer mobile emotion recognition tasks and social affiliation in predicting in real-time suicide disclosure through ecological momentary assessment over 30 days. We will then evaluate whether social cognition and affiliation markers predict trajectories of help seeking and suicide ideation through longitudinal data gathered over one year. Exploratory analyses will leverage the data derived by applying time series network analyses and natural language processing to model processes underlying non-disclosure. Our long-term goal is to translate this research to novel personalized interventions that improve interpersonal processes embedded in both current and novel suicide prevention approaches for older adults. This proposal responds directly to NIMH Strategic Plan, Aim 2.2 and 3.2, and the NIMH’s Priority Area in Digital Mental Health.

NIH Research Projects · FY 2026 · 2023-01

ABSTRACT A significant portion of patients in the United States will suffer from chronic pain at some point in their lives, and for a portion of these patients, our current medical and surgical options are inadequate. Novel treatments aimed at stimulating cerebral circuits involved in nociception for clinical pain relief are promising, but require further development of both targeting and stimulation strategies. Yet, the neural mechanisms of how human nociception manifests as the perception of pain in cerebral circuits remains poorly understood. This proposal leverages neurophysiological access to cortical and subcortical targets in patients undergoing the placement of intracranial EEG electrodes to characterize pain networks in the human brain with specific access to the less often studied nodes in the “pain network” thought to be associated with the emotional and cognitive spheres of pain processing, including the prefrontal cortex, amygdala, insula, and anterior cingulate regions. This unique access will allow detailed exploration of the pain experience in a naturalistic setting based on patients’ self- reported measures of post surgical pain, which will then be contrasted with opiate induced pain reduction. The subset of patients with pre-existing chronic pain conditions will be analyzed for variation in the biomarker signal. Our preliminary findings have yielded two overarching hypotheses: 1) periods of self-reported post- surgical pain will be associated with reduced beta power in prefrontal cortex, an association that will be reversed by the administration of opioids associated with pain relief and 2) the subset of patients with pre- existing chronic pain conditions will have predictable variance, with increases in baseline high beta/low gamma signal compared to patients without chronic pain. Through the use of novel clinical-research hybrid electrodes that allow for targeted, high-resolution electrophysiological recordings, candidate target regions will then be stimulated in an effort to re-create the associated pain reduced state electrophysiologically and clinically. This unique access into human pain circuits will guide further understanding of the physiology of these neural signatures and advance the long-term goal of developing novel paradigms to therapeutically modulate cerebral circuits for the treatment of chronic, intractable pain. This mentored award will provide critical and tailored training in 1) advanced aspects of neurophysiology 2) human experimental and clinical trial design, 3) rigorous epidemiological methods, 4) advanced biostatistics, and 5) validated psychophysical methods for the assessment of pain under the direction of Dr. Eric Halgren, a leading human neurophysiologist. A complementary team of co-mentors, advisors, and consultants has been assembled, including Mary Heinricher, a leader in the field of human and animal pain modulation, Terry Sejnowski, a pioneer in the field of theoretical neurobiology, Mark Wallace, an expert in the field of adult pain management, and Fadel Zeidan, an expert in the functional imaging of pain pathways in humans. The proposed research alongside a detailed career-development plan will facilitate an improved understanding of the anatomical and electrophysiological substrates of human pain, and lay the foundation for a successful transition towards an independent research career focused on the data-driven advancement of neurosurgical therapeutic modalities for chronic pain.

NIH Research Projects · FY 2026 · 2022-12

PROJECT SUMMARY/ABSTRACT Women have higher rate of Alzheimer's disease (AD) and tend to show a more aggressive profile of AD than men, with greater pathological tau burden and steeper cognitive decline. The prevalence of AD also differs by race with higher rates among Black versus White older adults. Yet, very little is known about AD in Black individuals given their historical exclusion in research. Even less is known about the intersection of race and sex in AD. In this proposal, we aim to study how sex- and/or race-disparate biological (inflammation, insulin resistance [IR]) pathways and physical activity potentially contribute to tau accumulation and cognitive decline specifically among older Black women at-risk for AD. We focus on potentially modifiable risk/protective factors given the recent surge in evidence that modification of these factors can be highly effective in delaying or even preventing cognitive decline. Our own preliminary work indicated that women may be more susceptible than men to the adverse effect of inflammation on levels of phosphorylated tau (p-tau) and cognitive function. There is also evidence that certain lifestyle factors, including physical activity, have a greater impact on AD-related outcomes such as tau in women versus men. Given links between physical activity and inflammation, we propose to investigate the interplay between inflammation and physical activity in their contributions to tau and cognitive decline in older Black women at risk for AD. Since IR is a key driver of inflammation, and the rates of prediabetes/diabetes are higher in Black adults, we will examine how IR impacts tau accumulation and cognitive decline. It is critical to examine these relationships in the context of social determinants of health, which are a driving factor in health outcomes such as inflammation and IR particularly in Black women. To achieve this, we propose a prospective study that will assess all variables of interest and their interactive pathways. The proposed study will build upon an ongoing pilot study that will collect these variables in 30 White women by study end (June, 2022), but will represent a more targeted and less invasive study in order to enhance recruitment in the understudied yet higher risk group of older Black women. We propose to recruit Black women at two sites, one leveraging an existing research registry of Black women in Los Angeles, and the other leveraging local community connections and previous research experience to create a new cohort in San Diego. We will use a community-based participatory research approach to recruitment that involves decision making at each level involving a Community Advisory Board. We will measure inflammatory markers in blood, IR, physical activity and the Area Deprivation Index as our primary social determinant of interest in 100 Black women at-risk for AD and relate these measures to changes in cognitive function and accumulation of tau, measured in plasma, over a two-year period. This project will help to close critical gaps in our understanding of risk factors for AD in Black women by examining biomarkers and social determinants of health in this under-researched yet highly- vulnerable group. Furthermore, our findings will inform risk reduction strategies that influence these mechanisms.

NIH Research Projects · FY 2026 · 2022-12

PROJECT SUMMARY COVID-19 is associated with cognitive impairment that may persist long after infection. COVID-19 risk factors overlap with those for Alzheimer’s disease (AD), including older age, the APOE4 allele, and vascular dysfunction, suggesting that pathology from one condition may exacerbate pathogenesis of the other. Blood- brain barrier (BBB) dysfunction may serve as a common pathogenic mechanism, as BBB breakdown has been identified in individuals at risk for AD and may facilitate COVID-19-related neural injury via binding of SARS- CoV-2 to cerebrovascular endothelial cells or via virally-mediated neuroinflammation. Sex is also a risk factor for both diseases, with increased AD risk for women and sex-specific risk for acute and chronic COVID-19 symptoms, which may be partially mediated by sex hormone regulation of SARS-CoV-2 binding, inflammation, immune activity, or BBB dysfunction. The intersection of latent AD neuropathology with neuroinflammation or cerebrovascular dysfunction triggered by COVID-19 among the aging population may ignite a perfect storm of neurodegenerative changes. Yet despite potential for convergence of the COVID-19 pandemic upon a pre- existing public health crisis of dementia, little research has been devoted to understanding the mechanistic overlap between these conditions or the potentially catastrophic public health consequences of their synergy. The proposed investigation will assess the neurobiological sequalae of COVID-19 in older adults along with their modification by sex, AD pathology, and AD genetic risk. Restriction spectrum imaging to measure brain microstructure and dynamic contrast-enhanced MRI to estimate BBB permeability will be conducted on adults aged 50 years or older with previous COVID-19 infection (CV) and disease-related cognitive impairment, and on uninfected healthy controls. Cognitive testing will be conducted at time of neuroimaging and annually for up to four additional years. AD polygenic hazard scores (PHS), estrogen and testosterone levels, and plasma p- tau181, will be measured for all participants, and lifetime estrogen exposure will be calculated for women. This project will test the hypotheses that CV exhibit greater BBB breakdown, microstructural damage, and more severe cognitive impairment and decline than controls (Aim 1). AD risk (Aim 2) and sex (Aim 3) are predicted to modify effects of COVID-19 on brain and cognitive measures, with more severe disease-related brain injury, BBB permeability, and cognitive decline for those with high PHS or abnormal p-tau181 and for women. In sex- stratified analyses, testosterone and estrogen are expected to correlate with brain injury, BBB breakdown, and cognitive deficits (Aim 3). This study will pioneer the most advanced diffusion and permeability MRI techniques to clarify the yet elusive neurobiological effects of COVID-19 underlying its cognitive symptoms in older adults at elevated risk for neurodegenerative changes. It will advance our understanding of the currently speculative synergy between COVID-19 and AD pathogenesis as well as the complex role of sex and hormonal regulation in COVID-19-related neurological sequalae.

NIH Research Projects · FY 2026 · 2022-12

Project Summary Neuroinflammation is a major factor in the progression of Alzheimer's disease (AD). Inflammatory brain microglia are characterized by altered cholesterol and lipid metabolism. Cholesterol and many receptors governing inflammatory responses colocalize in the ordered membrane microdomains often designated as lipid rafts. Upon activation, lipid raft resident and recruited molecules assemble and initiate signaling cascades leading to inflammation. We have identified the apoA-I binding protein (AIBP, encoded by the APOA1BP gene) as a key regulator of cellular cholesterol metabolism, which can selectively target lipid rafts in inflammatory cells (inflammarafts) via its binding to TLR4. While extracellular AIBP regulates cholesterol depletion from the plasma membrane and controls lipid rafts, intracellular AIBP localizes to mitochondria, facilitates mitophagy and helps maintain normal mitochondrial function and control oxidative stress. Apoa1bp-/- APP/PS1 mice present more amyloid beta (Aβ) plaques, an exacerbated dysfunctional microglia phenotype and show increases in cell death when compared to APP/PS1 mice. Mitochondria in AIBP-deficient microglia are morphologically distorted, with a characteristic hyper-branched and cupped shape, typically seen following oxidative stress. The AAV-mediated expression of a secreted form of AIBP in the brain of Apoa1bp-/- APP/PS1 mice restored the homeostatic microglia morphology. The goal of this proposal is to delineate mechanisms governing protective effects of AIBP in the AD brain, focusing on microglial lipid rafts and on mitochondrial dysfunction. Specifically, in Aim 1 we propose to test the hypothesis that extracellular AIBP reverses pathological lipid rafts in microglia to reduce neuroinflammation and protect against neurodegeneration in a mouse model of AD. We have identified a TLR4- binding domain in the AIBP molecule and demonstrated that an AIBP(ΔTLR4) variant, which does not bind TLR4, cannot reverse lipid raft alterations. Using AAV delivery, we plan to restore expression of secreted variants of AIBP in the brain of Apoa1bp-/- APP/PS1 mice and expect that AIBP(wt) but not AIBP(ΔTLR4) will lessen neuroinflammation, the Aβ plaque burden and accumulation of phospho-tau. We also expect improvements in memory and learning. In Aim 2, we will be testing the hypothesis that intracellular AIBP protects mitochondrial dynamics and function in a mouse model of AD. Mitochondria are the major sites displaying concentration of intracellular AIBP, and preliminary studies suggest AIBP involvement in control of mitochondrial function, mitophagy and oxidative stress. Methods will include correlated light microscopy and 3D EM across scales, leveraging advances in serial blockface scanning EM and EM tomography, along with correlated measures of bioenergetics by Seahorse. To test relevance of the proposed mechanisms to human AD, in Aim 3 we will characterize AIBP-related markers of lipid rafts and mitochondrial dysfunction in postmortem and biopsy brain sections from AD subjects.

NIH Research Projects · FY 2026 · 2022-12

PROJECT SUMMARY/ABSTRACT Locally advanced cancers remain a therapeutic challenge to eradicate. The most successful treatments for such patients continue to combine decades old classical cytotoxic chemotherapies with radiotherapy. While chemo-radiotherapy improves tumor control, using non-targeted drugs increases normal tissue damage in the irradiated field along with systemic toxicities precluding further treatment intensification. Targeted delivery approaches can improve the chemo-radiotherapy paradigm by restricting highly potent radiosensitizers specifically to irradiated tumor targets that activate anti-tumor immune responses while simultaneously avoiding normal tissues. To test this hypothesis, we leveraged antibody drug conjugate (ADC) technology for receptor-restricted radiosensitization. ADCs split the roles of tumor targeting and killing into two distinct molecular tasks. Targeting is achieved by the antibody portion recognizing cell surface receptors preferentially found on tumor cells. Following cell surface receptor binding, ADCs are endocytosed and the attached drug payload warhead intracellularly released specifically within target cells. ADCs have been exclusively built by linking cytotoxic drugs to tumor targeting antibodies. The potent anti-tubulin drug monomethyl auristatin E (MMAE) is the most common ADC warhead. We discovered MMAE could also radiosensitize. Advancing to syngeneic murine models using our novel drug delivery vehicles, we have now provided the first demonstration that MMAE produces durable irradiated tumor control which is dependent on CD8 T cells and is enhanced by immune checkpoint inhibition. While antibody coupled, MMAE is target restricted. However once released, MMAE has dose limiting toxicities. To achieve increasingly precise tumor radiosensitization, we used orthogonal strategies and rationally constructed a first-in-class radiosensitizing ADC designed to inhibit DNA damage repair. As proof of concept, we conjugated anti-EGFR antibody cetuximab to ATM inhibitor AZD0156 (cetux-AZD0156). Cetux-AZD0156 specifically bound and delivered drug to EGFR+ tumors while avoiding adjacent peri-tumoral normal tissue. Moreover, cetux-AZD0156 radiosensitized and increased irradiated tumor control. Based on these findings, we hypothesize that anti-ErbB ADCs coupled to radiosensitizing warheads improve spatial precision of radiosensitization and engage the tumor immune microenvironment (TIME). The goals of this proposal are to methodically test this hypothesis by evaluating radiosensitizing ADC warheads in murine tumor models using our innovative toolbox of tumor-targeted radiosensitizing ADC warheads. In Aim 1, we will test the ability of auristatins to sculpt the irradiated TIME and promote immunogenic tumor control. In Aim 2, we will test if immunotherapies potentiate radiosensitizing auristatins to achieve durable tumor control. In Aim 3, we will test first-in-class ADCs with ATM inhibitor warheads for tissue selective radiosensitization. Rigorously testing radiosensitizing ADCs in advanced murine models will provide rationale for moving away from non-targeted chemo-radiotherapy toward molecularly guided precision radio-chemo-immunotherapies.

NIH Research Projects · FY 2026 · 2022-12

One of every 20 new cancer cases is diagnosed in an adolescent or young adult (AYA) aged 12–39 years. Both female and male AYA cancer patients experience increase risks of infertility and gonadal failure, devastating late effects which are preventable through effective fertility preservation (FP) services prior to cancer treatment. At the intersection of oncology and fertility, oncofertility care is the evidence-based practice of discussing reproductive risks with newly diagnosed cancer patients and supporting shared decision-making on FP services. Despite longstanding clinical guidelines, oncofertility care uptake is low because we currently lack scalable interventions to support its implementation in adult and pediatric cancer care settings. Drawing on implementation science, our transdisciplinary team conducted systematic environmental scans across 10 diverse health systems which corroborated prior research on barriers to care and led to the development, usability testing, pilot testing and tailoring of the multi-component telehealth oncofertility care (TOC) intervention. Intervention components are: 1) EHR-based oncofertility needs screen and referral pathway to a virtual oncofertility hub; 2) telehealth oncofertility counseling through the hub; and 3) telehealth oncofertility financial navigation through the hub. The proposed TOC trial is a stepped wedge cluster randomized trial of 18 adult and pediatric oncology clinics across three health systems. We will test the hypotheses that the intervention condition will be associated with increased proportion of patients who engage in goal-concordant oncofertility care (i.e., engagement in reproductive risk counseling and fertility preservation services that meet the patient’s fertility goals) (Aim 1) and improved patient-reported outcomes and achievement of patient-centered goals (Aim 2), compared to the usual care control condition. To decrease the time lag from research discovery to clinical care, we will evaluate intervention implementation using mixed methods guided by implementation science frameworks (Aim 3). The TOC intervention is innovative for its multi-level approach, medical financial hardship target, hub and spoke model bridging a virtual oncofertility hub with multi-institutional oncology clinics, and focus on contextual fit that enables implementation across separate EHR instances and in both adult and pediatric settings. The proposal is innovative in taking an implementation science-informed approach that considers policy, organizational context, and patient preference to evaluate effectiveness and implementation for future scale-up. IMPACT: Responsive to Congress’ Childhood Cancer Survivorship, Treatment, Access and Research (STAR) Act of 2018 and NCI’s NOSIs on use of telehealth in cancer-related care (NOT-CA-21-043) and addressing cancer-related financial hardship (NOT-CA-22-045), this proposal has the potential for high clinical impact through reducing significant inequities in access to oncofertility care and enabling AYA cancer patients to engage in care that preserves their reproductive futures and improves life after cancer.

NIH Research Projects · FY 2026 · 2022-11

SUMMARY Although improvements have been made to the antimalarial drug discovery pipeline over the past decade a substantial risk remains that many new drug candidates may fail in clinical trials due to the rapid emergence of drug resistant parasites. The longterm goal of this research is to design better preclinical drug candidates for both malaria and to understand why treatments may fail. Over the past decade, our investigative team has established robust methodologies for discovering and characterizing genes involved in multidrug resistance and has assembled a large dataset of genes and alleles that mediate or are associated with multidrug resistance. The overall objective of this application is to extend and leverage these data to determine when, how and why antimalarial drug resistance or persistence emerges. Our central hypothesis is that the emergence of clinical drug resistance can be predicted using in vitro evolution assays. We also posit that resistance parameters may differ substantially between current field isolates exposed to modern first-line drugs and other selective pressures, as compared with reference laboratory strains isolated decades ago. Our hypotheses will be tested by pursuing three specific aims. In Aim 1, we will use adaptive laboratory evolution and deep whole-genome sequencing to obtain a high-resolution view of drug resistance acquisition. To accomplish this, we will define the extent to which a parasite’s genetic background plays a role by comparing results from recent African, Asian and South American clinical isolates to those obtained with laboratory strains dating back >40 years. We will also test whether these strains differ fundamentally in their mutational paths, levels of and time to resistance, the minimum inoculum of resistance and the impact of resistance on parasite fitness. We will also answer the critical question of whether resistance liabilities are more a function of the target or of the chemotype, parameters that contribute to resistance emergence such as number of genome replication events and the number of different alleles and whether different chemical chemotypes interacting with a given drug target give different results. In Aim 2, we will seek to understand mechanisms of resistance in a panel of poorly understood mediators. These studies will combine conditionally regulated genetic, proteomic, cellular and structural approaches to studying the impact of genetic changes conferring resistance on parasite biology. In Aim 3, we will explore the role that P. falciparum genes play in mediating drug tolerance as a means to survive antiplasmodial pressure. Innovation includes characterizing the evolution of resistance in geographically distinct modern field isolates instead of relying entirely on historical laboratory strains. Novelty includes assessing whether the resistance risk is driven by the target or the chemotype,and defining the role for tolerance in surviving antimalarial exposure. This research is significant because it will alter the way in which drug candidates are selected prior to extensive clinical and preclinical studies, ideally at the early lead stage.

NIH Research Projects · FY 2025 · 2022-09

Abstract HIV-1 infects resident cells of the central nervous system (CNS) leading to neuropathogenesis. HIV- neuropathogenesis is likely caused by direct and indirect viral and host factors. However, the exact underlying mechanisms remain unclear. Despite the success of antiretroviral therapy (ART) in suppressing HIV replication, near half of people living with HIV (PLWH) still have varying degrees of HIV-associated neurological disorders (HAND). There is also evidence that the CNS serves as an HIV reservoir and sanctuary site that may allow low level viremia, contributing to persistent neuroinflammation. The evolving molecular events underlying HIV neuropathogenesis are difficult to delineate, partially due to the lack of realistic HIV animal models and because human brain tissues rarely become available for studies until patients die, often due to advanced diseases. Human brain cortical organoids (BCO) are an emerging, cutting-edge technology for studying neuropathological disorders; because of their human origin, they better match the genomic and structural features of the developing human brain compared to animal models. This model consists of a self-assembled dynamic 3-D structure that provides an interplay of different cell types, which is limited in traditional monolayer cultures. We optimized protocols to generate long-term viable and functional BCO. Our BCO model has an unprecedented cell type diversity, via a dynamic development from progenitor cells to neuronal cells, that become interspersed with quiescent astrocytes over time; a difficult phenotype to obtain ex vivo. With the cellular components for generation of a functional neural network in place, our BCO model shows a robust extracellular electrical activity at early stages and progressively develops into an organized oscillatory network. Additionally, we have previously established methods for integration of iPSC-derived microglia into the BCO forming an assembloid, which is crucial tor this study. A BCO assembloid model containing relevant immune cell types will enable susceptibility to HIV and the study of the contributions of different cell types to the neurological consequences of infection. Using this robust and functional BCO assembloid, we propose to develop a new human model to study the cellular and molecular mechanisms underlying HIV neuropathogenesis, and the potential interactive, additive, or synergistic effects of antiretroviral treatment (ART) and opioid exposure. This microglia-infused BCO with endogenous astrocytes will allow HIV infection and its related pathophysiological events and help to disentangle the contribution and interplay of relevant immune cells to neuropathogenesis.

NIH Research Projects · FY 2025 · 2022-09

PROJECT SUMMARY Endovascular surgeries (ES) increasingly augment or replace traditional open surgical treatment of brain, liver, heart, and vascular diseases due to their improved clinical outcomes, faster recovery times, and improved mor- tality rates. These surgeries are commonly performed by inserting endovascular equipment into the groin or arm and navigating to distal arteries through a combination of axial loading and rotation of the base of the tools, utilizing the curved tips to deflect into intended locations and vessels. Despite the many benefits of endovascular surgeries, vascular anatomy, particularly for elderly patients who represent a large portion of those undergoing such procedures, can demonstrate excessive tortuosity and severe angulation, leading to high-risk , time-intensive procedures that can only be performed by a select number of expertly trained specialists. The small number of specialists results in limited access to necessary treatment, and patients are forced to either wait and travel for treatment or to not receive treatment at all. There is therefore a critical need for new endovascular robotic surgical tools that are safe, e↵ective, and that enable more surgeons to successfully navigate challenging anatomies. To address this need, a new soft-robotic approach called VINE – Vascular Internal Navigation by Extension – will be used. When pressurized with fluid, these VINEs navigate via extension at their tip in a man- ner analogous to how plants grow, creating shapes with complex curvatures. These VINEs are inherently safer due to their soft structure and represent a fundamentally di↵erent method of movement. The overall objective of this work is to characterize the behavior and refine the design of the VINE for ES, including the shape control methods, and to validate its e"cacy and safety. The central hypothesis is that this new method of shape control and navigation via tip-extension enables VINEs to safely and e↵ectively traverse the vasculature. The central hypothesis will be tested by pursuing three specific aims: (1) characterize and refine small-scale, pre-shaped and steerable VINE designs for ES, (2) evaluate VINE e"cacy in bench-top models, and (3) validate the safety of the entire VINE system in an in vivo pig study. This work will serve as a first step towards achieving the long-term goal of creating a soft robotic catheterization system, operable by a large number of surgeons, to increase access to high-quality surgical treatment. This work is innovative in that the proposed VINE is the first everting, robotic catheter with shape control and represents a substantive departure from the status quo, which currently relies on pushing semi-rigid instruments from their proximal end. The expected contribution of this work is a preliminary soft, tip-extending robotic system capable of safely and e↵ectively navigating around acute turns and through winding paths of the vasculature, which is significant since it will ultimately lead to increased access to high-quality minimally invasive procedures.

NIH Research Projects · FY 2025 · 2022-09

7. Project Summary The accumulation of misfolded proteins concurrent with disease progression is a hallmark of degenerative disorders known collectively as proteinopathies. These include dementias such as Alzheimer’s, Parkinson’s and Huntington’s Disease among many others, as well as systemic amyloidosis disorders. However, if and how aggregated species contribute to disease etiology and progression remains poorly understood. Over the past 100 years, there has been significant advancement in understanding the pathological signatures and risk factors of proteinopathies but the molecular mechanisms of disease have remained elusive. In this application, I propose the development of new chemical tools for selectively manipulating aggregate proteostasis in cells and in vivo using a targeted protein degradation approach. To demonstrate feasibility, this approach was previously applied to investigate misfolded tau, leading to new insights into tau as a mediator of cell stress vulnerability in frontotemporal dementia neurons. Several strategies are presented to improve the throughput, scope, and utility of this approach across proteinopathies, as well as future applications. The major innovation of the proposed research is to take technologies and concepts learned from the field of targeted protein degradation (TPD) for cancer therapy, which has been an exceptionally active and successful area of research over the past 5 years, and apply them to central challenges in neurodegenerative diseases, where TPD has yet to be applied broadly. I believe this approach has high potential to yield significant advancement in both our understanding of the molecular mechanisms underlying neurodegenerative diseases and in identifying new therapeutic strategies to treat them.

NIH Research Projects · FY 2025 · 2022-09

Project Summary Current clinical data show that there is no effective treatment of sporadic or any form of hereditary amyotrophic lateral sclerosis. Our previous work and preliminary data show that two-level spinal subpial delivery of AAV9- shRNA-SOD1 vector is highly effective in blocking the disease development or progression if treatment is initiated in adult pre-symptomatic or early-symptomatic ALS mouse (SOD1G37R) or ALS rat (SOD1G93A). This functionally-defined protection correlated with a high degree of spinal α-motoneuron, interneuron and white matter preservation, and silencing of ALS-causing mutated SOD1 gene expression seen in the entire length of the spinal cord in both mouse and rat ALS models. At present no long post-treatment survival periods have been systemically studied as yet. In our proposed studies, using the SOD1G93A rat model, we will define: i) The maximum duration of clinically defined treatment effect after subpial delivery of AAV9-shRNA-SOD1 in adult pre- symptomatic or early symptomatic SOD1G93A rats. ii) In a separate cohort of wild-type SD rats and pigs, a SOD1 silencing vector will be used to study the toxicity threshold after endogenous SOD1 gene silencing. The aims, research design, and methods have been developed to focus on mutated SOD1 gene-induced ALS, and to generate comprehensive efficacy and initial safety data to support future pre-clinical development of this treatment approach, as a novel therapeutic strategy for augmenting mutated SOD1 gene-caused ALS.