Selected Grantee Publications
Establishing the Hybrid Rat Diversity Program: A Resource for Dissecting Complex Traits
Dwinell et al., Mammalian Genome. 2025.
https://pubmed.ncbi.nlm.nih.gov/39907792
Rat models have been extensively used for studying human complex disease mechanisms, behavioral phenotypes, and environmental factors and for discovering and developing drugs. Systems genetics approaches have been used to study the effects of both genetic variation and environmental factors. This approach recognizes the complexity of common disorders and uses intermediate phenotypes to find relationships between genetic variation and clinical traits. This article describes the Hybrid Rat Diversity Program (HDRP) at the Medical College of Wisconsin, which involves 96 inbred rat strains and aims to provide a renewable and reusable resource in terms of the HRDP panel of inbred rat strains, the genomic data derived from the HRDP strains, and banked resources available for additional studies. Supported by ORIP (R24OD024617) and NHLBI.
Suppression of Viral Rebound by a Rev-Dependent Lentiviral Particle in SIV-Infected Rhesus Macaques
Hetrick et al., Gene Therapy. 2025.
https://pubmed.ncbi.nlm.nih.gov/39025983/
Viral reservoirs are a current major barrier that prevents an effective cure for patients with HIV. Antiretroviral therapy (ART) effectively suppresses viral replication, but ART cessation leads to viral rebound due to the presence of viral reservoirs. Researchers conducted in vivo testing of simian immunodeficiency virus (SIV) Rev-dependent vectors in SIVmac239-infected male and female Indian rhesus macaques, 3–6 years of age, to target viral reservoirs. Treatment with the SIV Rev-dependent vector reduced viral rebound and produced neutralizing antibodies following ART cessation. These results indicate the potential to self-control plasma viremia through a neutralizing antibody-based mechanism elicited by administration of Rev-dependent vectors. This research could guide future studies focused on investigating multiple vector injections and quantifying cell-mediated immune responses. Supported by ORIP (P51OD011104, P40OD028116), NIAID, and NIMH.
Functional Differences Between Rodent and Human PD-1 Linked to Evolutionary Divergence
Masubuchi et al., Science Immunology. 2025.
https://pubmed.ncbi.nlm.nih.gov/39752535/
Programmed cell death protein 1 (PD-1), an immune checkpoint receptor, regulates immunity against cancer. Rodent models (e.g., mice) do not exhibit the same response rates and immune-related adverse effects to PD-1 blocking drugs as patients with cancer. Only 59.6% amino acid sequence identity is conserved in human PD-1 (hu PD-1) and mouse PD-1 (mo PD-1). Researchers used mouse tumor models, coculture assays, and biophysical assays to determine key functional and biochemical differences between hu PD-1 and mo PD-1. HuPD-1 demonstrates stronger suppressive activity of interleukin-2 secretion and CD69 expression than mo PD-1 because of the ectodomain and intracellular domain, but not the transmembrane domain. Analysis of rodent evolution demonstrated that other inhibitory immunoreceptors were positively selected or had selection intensification over PD-1. Understanding the conservation and divergence of PD-1 signaling at the molecular level in humans compared with mice is needed to properly translate preclinical data to clinical therapeutics. Supported by ORIP (S10OD026929), NCI, and NIA.
Targeting Pancreatic Cancer Cell Stemness by Blocking Fibronectin-Binding Integrins on Cancer-Associated Fibroblasts
Wu et al., Cancer Research Communications. 2025.
https://pubmed.ncbi.nlm.nih.gov/39785683
Cancer-associated fibroblasts (CAFs) stimulate the formation and progression of pancreatic adenocarcinoma (PDAC) through the generation of extracellular matrix (ECM). Researchers developed a bispecific antibody (bsAb) that targets α5β1 and αvβ3 integrins expressed on CAFs. Blockade using the bsAb resulted in reduced assembly of fibronectin and collagen fibers in vitro. An antifibrotic effect was observed when CAFs were plated for 72 hours prior to bsAb treatment; pre-deposited ECM was disrupted. Six- to 8-week-old female nu/nu mice treated with bsAb demonstrated fewer tumors and reduced tumor stiffness compared with those exposed to only CAFs co-injected with PDAC cells. These results support a potential novel PDAC therapeutic that targets CAF-mediated fibronectin assembly and ECM production. Supported by ORIP (K01OD030513) and NCI.
Integrative Multi-omics Analysis Uncovers Tumor-Immune-Gut Axis Influencing Immunotherapy Outcomes in Ovarian Cancer
Rosario et al., Nature Communications. 2024.
https://pubmed.ncbi.nlm.nih.gov/39638782
Recurrent ovarian cancer (OC) is the deadliest gynecological malignancy, with a 5-year survival rate of 50% and a median progression-free survival (PFS) of 1.9 to 2.1 months. A trial cohort of 40 patients was treated with a combination of the anti-PD-1 pembrolizumab, the anti–vascular endothelial growth factor bevacizumab, and cyclophosphamide. The investigators conducted a multi-omics analysis—including transcriptomic analysis, digital spatial profiling, 16s-rRNA sequencing, and metabolomics—to understand the underlying mechanisms for the enhanced PFS to a median of 10.2 months and overall response rate of 47.5%. Multi-omics analysis highlighted the formation of tertiary lymphoid structures known to improve responses to immunotherapy, differential microbial patterns, and alterations in the metabolites in three key metabolism pathways that enhanced immune response in patients to produce a durable clinical response. These findings highlight the importance of the tumor microenvironment and the gut microbiome, along with its metabolites, in elevating the efficacy of the cocktail therapy in recurrent OC patients, thereby enhancing their survival and quality of life. Supported by ORIP (S10OD024973) and NCI.
A Switch from Glial to Neuronal Gene Expression Alterations in the Spinal Cord of SIV-Infected Macaques on Antiretroviral Therapy
Mulka et al., Journal of Neuroimmune Pharmacology. 2024.
https://pubmed.ncbi.nlm.nih.gov/38862787/
Up to one-third of patients with HIV experience HIV-associated peripheral neuropathy, affecting sensory pathways in the spinal cord. Spinal cord sampling is limited in people with HIV. Researchers examined gene expression alterations in the spinal cords of simian immunodeficiency virus (SIV)-infected male pigtail macaques with and without antiretroviral therapy (ART), using RNA sequencing at key time points throughout infection. Results indicate a shift from glial cell-associated pathways to neuronal pathways in SIV-infected animals receiving ART. These findings suggest that neurons, rather than glia, are predominantly involved in ART-related neurotoxicity and offer new insights into therapeutic strategies for maintaining synaptic homeostasis. Supported by ORIP (U42OD013117, T32OD011089) and NINDS.
Aberrant Activation of Wound-Healing Programs within the Metastatic Niche Facilitates Lung Colonization by Osteosarcoma Cells
Reinecke et al., Clinical Cancer Research. 2024.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11739783/
The leading cause of deaths in the pediatric osteosarcoma is due to lung metastasis. A current clinical need is the development of therapies that disrupt the later stages of metastasis. Researchers used 6- to 8-week-old female C57BL/6 and CB17-SCID mice to understand how tumor cells disrupt the lung microenvironment to promote tumor growth. Single-cell RNA sequencing and spatial transcriptomics demonstrated osteosarcoma–epithelial cell interactions in a chronic state of wound healing in the lung. Nintedanib administration significantly disrupted metastatic progression compared with the vehicle control, demonstrating a potential novel therapeutic for combating osteosarcoma lung metastasis. Supported by ORIP (K01OD031811), NCI, and NCATS.
SREBP-Dependent Regulation of Lipid Homeostasis Is Required for Progression and Growth of Pancreatic Ductal Adenocarcinoma
Ishida et al., Cancer Research Communications. 2024.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11444119
Lipids are crucial for tumor cell proliferation, and sterol regulatory element-binding protein (SREBP) activation drives lipid synthesis and uptake to maintain cancer growth. This study investigated the role of the SREBP pathway and its regulator, SREBP cleavage–activating protein (SCAP), in lipid metabolism during the development and progression of pancreatic ductal adenocarcinoma (PDAC). Using female mouse xenograft models and male and female pancreas-specific Scap knockout transgenic mice, researchers demonstrated that SCAP is essential for PDAC progression in low-nutrient conditions, linking lipid metabolism to tumor growth. These findings highlight SREBP as a key therapeutic target for PDAC, offering potential strategies for improving treatment by disrupting cancer-associated metabolic reprogramming. Supported by ORIP (T32OD011089), NCI, NHLBI, and NIGMS.
Potent Broadly Neutralizing Antibodies Mediate Efficient Antibody-Dependent Phagocytosis of HIV-Infected Cells
Snow et al., PLOS Pathogens. 2024.
https://pubmed.ncbi.nlm.nih.gov/39466835
This study investigates the role of potent broadly neutralizing antibodies (bNAbs) in mediating antibody-dependent cellular phagocytosis (ADCP) of HIV-infected cells. Researchers developed a novel cell-based approach to assess the ADCP of HIV-infected cells expressing natural conformations of the viral envelope glycoprotein, which allows the virus to infect a host cell. The findings in this study demonstrate that bNAbs facilitate efficient ADCP, highlighting their potential in controlling HIV infection by promoting immune clearance of infected cells. This study provides valuable insights into antibody-mediated immune mechanisms and supports the development of antibody-based therapies and vaccines targeting HIV. Supported by ORIP (P51OD011106) and NIAID.
Phenotypic Characterization of Subtype A and Recombinant AC Transmitted/Founder Viruses From a Rwandan HIV-1 Heterosexual Transmission Cohort
Yue et al., Viruses. 2024.
https://pubmed.ncbi.nlm.nih.gov/39599821
HIV-1 is classified into several phylogenetic groups and subgroups, and to be effective, a vaccine would require broad activity across diverse viral strains. The most widespread group, M, is subdivided into several subgroups (A–D, F–H, J, K, and L). In a previous study, these researchers analyzed cohorts of people with recent or acute HIV infection in Rwanda. Subtype A was the dominant subtype, but a significant number of infections were caused by recombinants of subtypes A and C. This study assessed the characteristics of 16 infectious molecular clones (IMCs) of subtype A or AC recombinant viruses. Viral replication scores varied among the IMCs, and amino acid substitutions in the viral Gag gene were linked to higher replication activity. The sensitivity of different clones to broadly neutralizing antibodies also was assessed. This panel of well-characterized viral IMCs will support studies required to develop an effective HIV-1 vaccine. Supported by ORIP (P51OD011132) and NIAID.