Selected Grantee Publications
- Clear All
- 137 results found
- Nonhuman Primate Models
- Vaccines/Therapeutics
Biphasic Decay of Intact SHIV Genomes Following Initiation of Antiretroviral Therapy Complicates Analysis of Interventions Targeting the Reservoir
Kumar et al., PNAS. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10614214/
The latent HIV-1 reservoir persists with antiretroviral therapy (ART), and assays for quantifying intact proviruses in nonhuman primate models are needed. Researchers used a simian–human immunodeficiency virus (SHIV) intact proviral DNA assay to describe viral decay during the first year of ART in female rhesus macaques. Their results suggest that intact SHIV genomes in circulating CD4+ T cells undergo biphasic decay during the first year of ART, with a rapid first phase and a slower second phase. These findings can provide insight for future studies using SHIV models, as well as new cure interventions. Supported by ORIP (R01OD011095) and NIAID.
CD8+ Cells and Small Viral Reservoirs Facilitate Post-ART Control of SIV Replication in M3+ Mauritian Cynomolgus Macaques Initiated on ART Two Weeks Post-Infection
Harwood et al., PLOS Pathogens. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10553806/
A rare group of people infected with HIV can achieve sustainable HIV remission after antiretroviral therapy (ART) withdrawal, but the underlying mechanisms are not understood fully. A team of investigators observed post-treatment control in a cohort of male cynomolgus macaques that were initiated on ART 2 weeks post-infection. Additionally, they reported that the cynomolgus macaques had smaller acute reservoirs than similarly infected rhesus macaques. Collectively, these data suggest that a combination of small reservoirs and immune-mediated virus suppression contributes to post-treatment control in cynomolgus macaques. This model could be used in future studies to develop therapeutic interventions. Supported by ORIP (P51OD011106, P40OD028116), NIAID, and NCI.
Long-Acting Lenacapavir Protects Macaques Against Intravenous Challenge With Simian-Tropic HIV
Swanstrom et al., eBioMedicine. 2023.
https://doi.org/10.1016/j.ebiom.2023.104764
Pre-exposure prophylaxis (PrEP) is effective in preventing new HIV infections, but regimen adherence remains a challenge. Antiretrovirals with long-acting pharmacokinetic properties could help overcome this limitation. Researchers examined the protective efficacy of lenacapavir, a first-in-class HIV capsid inhibitor, using male pigtail macaques. They reported that a single administration of the drug provided protection from simian-tropic HIV infection. These data demonstrate the value of this nonhuman primate model and support the clinical development of long-acting lenacapavir for PrEP in humans. Future studies could further explore and refine the drug exposure–efficacy relationship. Supported by ORIP (P40OD028116), NIAID, and NCI.
Downregulation of CCR5 on Brain Perivascular Macrophages in Simian Immunodeficiency Virus–Infected Rhesus Macaques
Bollimpelli et al., Nature Communications. 2023.
https://www.doi.org/10.1038/s41467-023-40430-7
Researchers have been exploring multiple strategies to develop an HIV vaccine. In this study, the investigators determined the immunogenicity and efficacy of intradermal and intramuscular routes of modified vaccinia Ankara (MVA) vaccination in female rhesus macaques. They found that both routes of MVA vaccination enabled control of viral replication, but only the intradermal vaccination was effective in protection against viral acquisition. Their findings suggest that the intradermal MVA vaccinations provide protection by modulating the innate and T helper responses. Taken together, this work underscores the importance of testing the influence of the route of immunization for HIV vaccines in humans. Supported by ORIP (P51OD011132, R24OD010976) and NIAID.
Antiretroviral Therapy Ameliorates Simian Immunodeficiency Virus–Associated Myocardial Inflammation by Dampening Interferon Signaling and Pathogen Response in the Heart
Robinson et al., The Journal of Infectious Diseases. 2023.
https://doi.org/10.1093/infdis/jiad105
HIV is associated with increased risk of cardiovascular disease, but the underlying mechanisms are not fully understood. Using RNA sequencing, investigators characterized the effects of simian immunodeficiency virus (SIV) infection on the hearts of male rhesus macaques. They demonstrated that SIV infection drives a canonical antiviral response in the heart, as well as dysregulation of genes involved in fatty acid shuttling and metabolism. Their findings suggest that antiretroviral therapy helps mitigate immune activation during viremic conditions and plays a cardioprotective role. Future studies are needed to assess the long-term effects of these dynamics. Supported by ORIP (P51OD011104), NIAID, NIMH, and NINDS.
Allogeneic Immunity Clears Latent Virus Following Allogeneic Stem Cell Transplantation in SIV-Infected ART-Suppressed Macaques
Wu et al., Immunity. 2023.
https://doi.org/10.1016/j.immuni.2023.04.019
Allogeneic hematopoietic stem cell transplantation (alloHSCT) has been documented as curative for HIV, but the mechanisms are not yet known. Using Mauritian cynomolgus macaques of both sexes, researchers performed reduced-intensity alloHSCT experiments to define the individual contributions of allogeneic immunity and CCR5 deficiency to an alloHSCT-mediated HIV cure. They reported that allogeneic immunity was the major driver of reservoir clearance, mediating graft-versus-reservoir effects in HIV infection. Their results also point to a protective mechanism for CCR5 deficiency early during engraftment. Future efforts could focus on harnessing the beneficial effects of allogeneic immunity while avoiding graft-versus-host disease. Supported by ORIP (P51OD011092) and NIAID.
Brain Microglia Serve as a Persistent HIV Reservoir Despite Durable Antiretroviral Therapy
Tang et al., The Journal of Clinical Investigation. 2023.
https://www.doi.org/10.1172/JCI167417
Brain microglia are likely to play a role in rebound viremia following the cessation of antiretroviral therapy, but more work is needed to fully understand HIV persistence in the central nervous system (CNS). The investigators developed a protocol to isolate highly pure populations of brain myeloid cells and microglia from the tissues of male rhesus macaques, as well as from rapid autopsies of men and women with HIV. Their observations support the concept that brain microglia are a stable reservoir of quiescent infection. Thus, this work provides a physiologically relevant platform for studies of the biology of CNS reservoirs. Supported by ORIP (P51OD011132), NIAID, and NIMH.
Lymph-Node-Based CD3+ CD20+ Cells Emerge From Membrane Exchange Between T Follicular Helper Cells and B Cells and Increase Their Frequency Following Simian Immunodeficiency Virus Infection
Samer et al., Journal of Virology. 2023.
https://www.doi.org/10.1128/jvi.01760-22
CD4+ T follicular helper cells are known to persist during antiretroviral therapy (ART) and have been identified as key targets for viral replication and persistence. Researchers identified a lymphocyte population that expresses CD3 (i.e., T cell lineage marker) and CD20 (i.e., B cell lineage marker) on the cellular surface in lymphoid tissues from rhesus macaques of both sexes and humans of male and female sexes. In macaques, the cells increased following simian immunodeficiency virus infection, were reduced with ART, and increased in frequency after ART interruption. These cells represent a potential area for future therapeutic strategies. Supported by ORIP (P51OD011132, U42OD011023), NIAID, NCI, NIDDK, NIDA, NHLBI, and NINDS.
Efficient Ex Vivo Expansion of Conserved Element Vaccine-Specific CD8+ T Cells from SHIV-Infected, ART-Suppressed Nonhuman Primates
Dross et al., Frontiers in Immunology. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10189133/
HIV-specific T cells are necessary for control of HIV-1 replication but are largely insufficient for viral clearance. Using male rhesus macaques, investigators sought to increase the frequency of specific T cell responses in vivo using an ex vivo cell manufacturing approach. The resulting products contained high frequencies of specific, polyfunctional T cells, but no significant differences in T cell persistence were observed, nor was acquisition of simian–human immunodeficiency virus (SHIV). This work underscores this animal model as an important approach to optimize the manufacturing of antigen-specific immune effectors that can prevent virus acquisition and control viral rebound after discontinuing antiretroviral therapy (ART). Supported by ORIP (P51OD010425, U42OD011123), NIAID, and NCI.
Probiotic Therapy During Vaccination Alters Antibody Response to Simian-Human Immunodeficiency Virus Infection But Not to Commensals
Wilson et al., AIDS Research and Human Retroviruses. 2023.
https://www.doi.org/10.1089/AID.2022.0123
Strategies to boost vaccine-induced mucosal humoral responses are critical to developing an HIV-1 vaccine, and probiotic supplementation could help boost antibody responses. Researchers analyzed antibody titers to explore this topic in rhesus macaques (sex not specified) infected with simian–human immunodeficiency virus (SHIV). They reported that probiotic treatment during vaccination led to delayed kinetics in the circulating HIV-specific IgA response after breakthrough SHIV infection. These findings highlight the potential of probiotic supplementation for reducing IgA-specific HIV antibodies in the plasma, which could help reduce HIV acquisition in vaccinated individuals. Supported by ORIP (P51OD011104, R21OD031435) and NIAID.