Selected Grantee Publications
Effect of Metabolic Status on Response to SIV Infection and Antiretroviral Therapy in Nonhuman Primates
Webb et al., JCI Insight. 2024.
https://pubmed.ncbi.nlm.nih.gov/39115937
This study examines how metabolic health influences the efficacy of antiretroviral therapy (ART). Using lean and obese male rhesus macaques, researchers explored the progression of simian immunodeficiency virus (SIV) infection. Obese macaques with metabolic dysfunction experienced more rapid disease progression and had a diminished response to ART than lean macaques. This study suggests metabolic health plays a significant role in HIV progression and treatment outcomes, highlighting the importance of managing metabolic conditions in people with HIV. Supported by ORIP (P51OD011092, S10OD025002), NIAID, and NIDDK.
Anti–PD-1 Chimeric Antigen Receptor T Cells Efficiently Target SIV-Infected CD4+ T Cells in Germinal Centers
Eichholtz et al., The Journal of Clinical Investigation. 2024.
https://pubmed.ncbi.nlm.nih.gov/38557496/
Researchers conducted adoptive transfer of anti–programmed cell death protein 1 (PD-1) chimeric antigen receptor (CAR) T cells in simian immunodeficiency virus (SIV)–infected rhesus macaques of both sexes on antiretroviral therapy (ART). In some macaques, anti–PD-1 CAR T cells expanded and persisted concomitant with the depletion of PD-1+ memory T cells—including lymph node CD4+ follicular helper T cells—associated with depletion of SIV RNA from the germinal center. Following CAR T infusion and ART interruption, SIV replication increased in extrafollicular portions of lymph nodes, plasma viremia was higher, and disease progression accelerated, indicating that anti–PD-1 CAR T cells depleted PD-1+ T cells and eradicated SIV from this immunological sanctuary. Supported by ORIP (U42OD011123, U42OD010426, P51OD010425, P51OD011092), NCI, NIAID, and NIDDK.
Murine MHC-Deficient Nonobese Diabetic Mice Carrying Human HLA-DQ8 Develop Severe Myocarditis and Myositis in Response to Anti-PD-1 Immune Checkpoint Inhibitor Cancer Therapy
Racine et al., Journal of Immunology. 2024.
Myocarditis has emerged as a relatively rare but often lethal autoimmune complication of checkpoint inhibitor (ICI) cancer therapy, and significant mortality is associated with this phenomenon. Investigators developed a new mouse model system that spontaneously develops myocarditis. These mice are highly susceptible to myocarditis and acute heart failure following anti-PD-1 ICI-induced treatment. Additionally, the treatment accelerates skeletal muscle myositis. The team performed characterization of cardiac and skeletal muscle T cells using histology, flow cytometry, adoptive transfers, and RNA sequencing analyses. This study sheds light on underlying immunological mechanisms in ICI myocarditis and provides the basis for further detailed analyses of diagnostic and therapeutic strategies. Supported by ORIP (U54OD020351, U54OD030187), NCI, NIA, NIDDK, and NIGMS.
SHIV-C109p5 NHP Induces Rapid Disease Progression in Elderly Macaques with Extensive GI Viral Replication
Bose et al., Journal of Virology. 2024.
https://pubmed.ncbi.nlm.nih.gov/38299866/
Researchers are interested in developing animal models infected with simian–human immunodeficiency virus (SHIV) to better understand prevention of HIV acquisition. Researchers generated pathogenic SHIV clade C transmitted/founder stock by in vivo passage using geriatric rhesus macaques of both sexes. They reported that the infection resulted in high sustained viral loads and induced rapid pathology and wasting, necessitating euthanasia between 3 and 12 weeks post-infection. The extensive viral replication in gut and lymphoid tissues indicated a fit viral stock. This work provides a new nonhuman primate model for HIV pathogenicity and cure studies. Supported by ORIP (R24OD010947) and NIDDK.
Tumor Explants Elucidate a Cascade of Paracrine SHH, WNT, and VEGF Signals Driving Pancreatic Cancer Angiosuppression
Hasselluhn et al., Cancer Discovery. 2024.
https://pubmed.ncbi.nlm.nih.gov/37966260/
This study presents a key mechanism that prevents pancreatic ductal adenocarcinoma (PDAC) from undergoing neoangiogenesis, which affects its development, pathophysiology, metabolism, and treatment response. Using human and murine PDAC explants, which effectively retain the complex cellular interactions of native tumor tissues, and single-cell regulatory network analysis, the study identified a cascade of three paracrine pathways bridging between multiple cell types and acting sequentially, Hedgehog to WNT to VEGF, as a key suppressor of angiogenesis in KRAS-mutant PDAC cells. This study provides an experimental paradigm for dissecting higher-order cellular interactions in tissues and has implications for PDAC treatment strategies. Supported by ORIP (S10OD012351, S10OD021764), NCI, and NIDDK.
HIV-1 Remission: Accelerating the Path to Permanent HIV-1 Silencing
Lyons et al., c. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10674359/
Current HIV treatment strategies are focused on forced proviral reactivation and elimination of reactivated cells with immunological or toxin-based technologies. Researchers have proposed the use of a novel “block-lock-stop” approach, which entails the long-term durable silencing of viral expression and permanent transcriptional deactivation of the latent provirus. In the present study, the authors present this approach and its rationale. More research is needed to understand the (1) epigenetic architecture of integrated provirus, (2) cell types and epigenetic cell states that favor viral rebound, (3) molecular functions of Tat (a protein that controls transcription of HIV) and host factors that prevent permanent silencing, (4) human endogenous retrovirus silencing in the genome, and (5) approaches to generate defective proviruses. Additionally, community engagement is crucial for this effort. Supported by ORIP (K01OD031900), NIAID, NCI, NIDA, NIDDK, NHLBI, NIMH, and NINDS.
CD8+ T Cells Control SIV Infection Using Both Cytolytic Effects and Non-Cytolytic Suppression of Virus Production
Policicchio et al., Nature Communications. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10589330/
HIV continuously evades and subdues the host immune responses through multiple strategies, and an understanding of these strategies can help inform research efforts. Using a mathematical model, investigators assessed whether CD8+ cells from male rhesus macaques exert a cytolytic response against infected cells prior to viral production. Their goal was to elucidate the possible mode of action of CD8+ cells on simian immunodeficiency virus (SIV)–infected cells. Models that included non‑cytolytic reduction of viral production best explained the viral profiles across all macaques, but some of the best models also included cytolytic mechanisms. These results suggest that viral control is best explained by the combination of cytolytic and non-cytolytic effects. Supported by ORIP (P40OD028116, R01OD011095), NIAID, NIDDK, and NHLBI.
Timing of Initiation of Anti-Retroviral Therapy Predicts Post-Treatment Control of SIV Replication
Pinkevych et al., PLOS Pathogens. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10558076/
Researchers are interested in approaches to reducing viral rebound following interruption of antiretroviral therapy, but more work is needed to understand major factors that determine the viral “setpoint” level. Researchers previously assessed how timing of treatment can affect the frequency of rebound from latency. In the current study, the authors analyzed data from multiple studies of simian immunodeficiency virus (SIV) infection in rhesus macaques to further explore the dynamics and predictors of post-treatment viral control. They determined that the timing of treatment initiation was a major predictor of both the level and the duration of post-rebound SIV control. These findings could help inform future treatments. Supported by ORIP (U42OD011023, P51OD011132, P51OD011092), NIAID, NCI, NIDA, NIDDK, NHLBI, NIMH, and NINDS
Enhanced IL-17 Producing and Maintained Cytolytic Effector Functions of Gut Mucosal CD161+ CD8+ T Cells in SIV-Infected Rhesus Macaques
Thirugnanam et al., Viruses. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10535321/
HIV infection is associated with the depletion of CD161-expressing CD4+ Th17 cells, but the effects on other IL-17–producing T cell subsets are not understood fully. Researchers characterized the functions of non-invariant CD161-expressing CD8+ T cell subpopulations in peripheral blood and mucosal tissues of rhesus macaques (sex not specified) during chronic simian immunodeficiency virus (SIV) infection. They demonstrated that cell frequencies and function were unaffected by infection, but enhanced IL-17 production capacity and sustained Th1-type and cytolytic functions were observed. This work suggests that CD161-expressing CD8+ T cells might have important functions in gut mucosal immunity during chronic HIV infection. Supported by ORIP (P51OD011104, S10OD026800), NIAID, NIDDK, and NIMH.
A Germ-Free Humanized Mouse Model Shows the Contribution of Resident Microbiota to Human-Specific Pathogen Infection
Wahl et al., Nature Biotechnology. 2023.
https://www.nature.com/articles/s41587-023-01906-5
Germ-free (GF) mice are of limited value in the study of human-specific pathogens because they do not support their replication. In this report, investigators developed a GF humanized mouse model using the bone marrow–liver–thymus platform to provide a robust and flexible in vivo model that can be used to study the role of resident microbiota in human health and disease. They demonstrated that resident microbiota promote viral acquisition and pathogenesis by using two human-specific pathogens, Epstein–Barr virus and HIV. Supported by ORIP (P40OD010995), FIC, NIAID, NCI, and NIDDK.