Selected Grantee Publications
- Clear All
- 7 results found
- Nonhuman Primate Models
- nhlbi
- 2023
Stable HIV Decoy Receptor Expression After In Vivo HSC Transduction in Mice and NHPs: Safety and Efficacy in Protection From SHIV
Li, Molecular Therapy. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10124088/
Autologous hematopoietic stem cell (HSC) gene therapy offers a promising HIV treatment strategy, but cost, complexity, and toxicity remain significant challenges. Using female mice and female nonhuman primates (NHPs) (i.e., rhesus macaques), researchers developed an approach based on the stable expression of eCD4-Ig, a secreted decoy protein for HIV and simian–human immunodeficiency virus (SHIV) receptors. Their goals were to (1) assess the kinetics and serum level of eCD4-Ig, (2) evaluate the safety of HSC transduction with helper-dependent adenovirus–eCD4-Ig, and (3) test whether eCD4-Ig expression has a protective effect against viral challenge. They found that stable expression of the decoy receptor was achieved at therapeutically relevant levels. These data will guide future in vivo studies. Supported by ORIP (P51OD010425) and NHLBI.
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
AZD5582 Plus SIV-Specific Antibodies Reduce Lymph Node Viral Reservoirs in Antiretroviral Therapy–Suppressed Macaques
Dashti et al., Nature Medicine. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10579098/
Researchers are interested in targeting the HIV reservoir via a latency reversal and clearance approach. Previously, investigators demonstrated that AZD5582 induces systemic latency reversal in rhesus macaques and humanized mice, but a consistent reduction in the viral reservoir was not observed. In the current study, they combined AZD5582 with four simian immunodeficiency virus (SIV)–specific rhesus monoclonal antibodies using rhesus macaques of both sexes. They reported a reduction in total and replication-competent SIV DNA in lymph node–derived CD4+ T cells in the treated macaques. These findings provide proof of concept for the potential of the latency reversal and clearance HIV cure strategy. Supported by ORIP (P51OD011132, R01OD011095), NIAID, NCI, and NHLBI.
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.
Prolonged Experimental CD4+ T-Cell Depletion Does Not Cause Disease Progression In SIV-Infected African Green Monkeys
Le Hingrat et al., Nature Communications. 2023.
https://www.nature.com/articles/s41467-023-36379-2
Chronically simian immunodeficiency virus (SIV)–infected African green monkeys (AGMs) partially recover mucosal CD4+ T cells, maintain gut integrity, and do not progress to AIDS. Investigators assessed the impact of prolonged, antibody-mediated CD4+ T cell depletion on gut integrity and natural history of SIV infection in AGMs. All circulating CD4+ T cells and more than 90% of mucosal CD4+ T cells were depleted. Plasma viral loads and cell-associated viral RNA in tissues were lower in CD4+-cell-depleted animals. CD4+-cell-depleted AGMs maintained gut integrity, controlled immune activation, and did not progress to AIDS. Therefore, CD4+ T cell depletion is not a determinant of SIV-related gut dysfunction when gastrointestinal tract epithelial damage and inflammation are absent, suggesting that disease progression and resistance to AIDS are independent of CD4+ T cell restoration in SIV-infected AGMs. Supported by ORIP (P40OD028116), NIAID, NIDDK, and NHLBI.
CD8+ Lymphocytes Do Not Impact SIV Reservoir Establishment under ART
Statzu et al., Nature Microbiology. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9894752/
The HIV-1 latent reservoir has been shown to persist following antiretroviral therapy (ART), but the mechanisms underlying the establishment and maintenance of the reservoir are not fully understood. Using rhesus macaques of both sexes, investigators examined the effects of CD8+ T cells on formation of the latent reservoir with simian immunodeficiency virus (SIV) infection. They found that CD8+ T cell depletion resulted in slower decline of viremia but did not change the frequency of infected CD4+ T cells in the blood or lymph nodes. Additionally, the size of the persistent reservoir was unchanged. These findings suggest that the viral reservoir is established largely independent of SIV-specific cytotoxic T lymphocyte control. Supported by ORIP (P51OD011132), NIAID, NCI, NIDDK, NIDA, NHLBI, and NINDS.