Selected Grantee Publications
- Clear All
- 127 results found
- Nonhuman Primate Models
- HIV/AIDS
Phagocytosis by an HIV Antibody Is Associated with Reduced Viremia Irrespective of Enhanced Complement Lysis
Spencer et al., Nature Communications. 2022.
https://doi.org/10.1038/s41467-022-28250-7
Researchers used the bNAb 10E8v4 targeting the HIV Env protein to examine the role of antibody-mediated effector and complement (C′) activity when 10E8v4 was administered prophylactically to rhesus monkeys challenged with simian-human immunodeficiency virus (SHIV). With sub-protective dosing, the researchers found a 78–88% reduction in post-acute viremia that was associated with 10E8v4–mediated phagocytosis. These results suggest that effector functions inherent to unmodified 10E8v4 contribute to therapeutic efficacy against SHIV, while C′ functions do not contribute to efficacy in this context. This research informs the design of bNAb modifications for improving the protective efficacy of this therapeutic approach against HIV. Supported by ORIP (P51OD011092, U42OD023038) and NIAID.
Vaccine-Induced, High-Magnitude HIV Env-Specific Antibodies with Fc-Mediated Effector Functions Are Insufficient to Protect Infant Rhesus Macaques against Oral SHIV Infection
Curtis et al., mSphere. 2022.
https://www.doi.org/10.1128/msphere.00839-21
A tailored, effective HIV vaccine is needed to prevent mother-to-child viral transmission. In nonhuman primate models, infection with simian–human immunodeficiency virus (SHIV) can be prevented by administering broadly neutralizing HIV envelope (Env)–specific antibodies. Investigators tested the efficacy of an intramuscular vaccine regimen against SHIV infection in male and female infant rhesus macaques. The vaccine induced Env-specific antibodies in plasma, with antibody-dependent cellular cytotoxicity and phagocytic function. These antibodies, however, were insufficient for protection against infection. Future studies could focus on improving the breadth of antibody response and improving cell-mediated immunity. Supported by ORIP (P51OD011107), NCI, NIAID, and NIDCR.
CAR/CXCR5–T Cell Immunotherapy Is Safe and Potentially Efficacious in Promoting Sustained Remission of SIV Infection
Pampusch et al., PLOS Pathogens. 2022.
https://www.doi.org/10.1371/journal.ppat.1009831
HIV and simian immunodeficiency virus (SIV) replication are concentrated within the B cell follicles of secondary lymphoid tissues. In this study, the researchers developed immunotherapeutic chimeric antigen receptor (CAR) T cells that home to follicles and clear SIV-infected cells in a rhesus macaque model. The CAR T cells localized to the follicle, replicated, and interacted directly with infected cells. Most of the treated animals maintained lower viral loads in the blood and follicles, compared to control animals. These findings demonstrate the safety and potential efficacy of this immunotherapy approach for long-term remission of HIV without requiring the lifelong use of antiretroviral therapy. Supported by ORIP (P51OD011106), NIAID, and NHLBI.
Simian Immunodeficiency Virus Infection Mediated Changes in Jejunum and Peripheral SARS-CoV-2 Receptor ACE2 and Associated Proteins or Genes in Rhesus Macaques
Boby et al., Frontiers in Immunology. 2022.
https://www.doi.org/10.3389/fimmu.2022.835686
Recent studies suggest that people with HIV—particularly those not receiving antiretroviral therapy or those with low CD4 cell counts—are at increased risk of severe illness from SARS‑CoV-2 coinfection. Angiotensin-converting enzyme 2 (ACE2), the cellular receptor for SARS-CoV-2, is likely to play an important role in modulating physiological and pathological events during HIV infection. In this study, the researchers used a rhesus macaque model to characterize the expression profiles of ACE2, other renin-angiotensin system (RAS)–associated genes (AGTR1/2, ADAM17, and TMPRSS2), and inflammatory cytokines (IL-1β, IL-6, and TNF‑α) in the jejunum and lung during simian immunodeficiency virus (SIV) infection. SIV infection was associated with multiple changes in gene expression, including downregulation of ACE2, which could lead to loss of gut homeostasis. Further studies could provide insight on the role of RAS-associated proteins during HIV and SARS-CoV-2 co-infection. Supported by ORIP (P51OD011104) and NIDDK.
Estimation of the In Vivo Neutralization Potency of eCD4Ig and Conditions for AAV-Mediated Production for SHIV Long-Term Remission
Goyal et al., Science Advances. 2022.
https://www.doi.org/10.1126/sciadv.abj5666
The engineered protein eCD4Ig, a synthetic antibody-like inhibitor designed to limit HIV entry into cells, shows promise as an approach to achieve HIV remission without antiretroviral therapy. Researchers used mathematical modeling to characterize in vivo antiviral neutralization of eCD4Ig, as well as possible antibody-dependent cell-mediated cytotoxicity effects, in rhesus macaques infected with simian–human immunodeficiency virus (SHIV) (sex not specified). The research team modeled SHIV and pharmacokinetics dynamics and projected the levels of eCD4Ig needed with a viral vector production approach to suppress SHIV viremia. The data suggest that endogenous, continuous expression of eCD4Ig could overcome the diminishing effects of antidrug antibodies and allow long-term remission of SHIV viremia in nonhuman primates. Supported by ORIP (P51OD011132) and NIAID.
Neuroinflammatory Profiling in SIV-Infected Chinese-Origin Rhesus Macaques on Antiretroviral Therapy
Solis-Leal et al., Viruses. 2022.
https://www.doi.org/10.3390/v14010139
The central nervous system (CNS) HIV reservoir contributes to residual neuroimmune activation, which can lead to HIV-associated neurocognitive disorder. Researchers characterized the expression of signaling molecules associated with inflammation in plasma, cerebrospinal fluid, and basal ganglia of Chinese-origin rhesus macaques (sex not specified) with simian immunodeficiency virus (SIV). They reported a correlation between levels of CCL2 in plasma and cerebrospinal fluid, suggesting that researchers could infer the degree of CNS inflammation by testing CCL2 levels in peripheral blood. Overall, these findings provide insight into neuroinflammation and signaling associated with HIV persistence in the CNS. Supported by ORIP (P51OD011104, P51OD011133), NIMH, and NINDS.
Cannabinoid Control of Gingival Immune Activation in Chronically SIV-Infected Rhesus Macaques Involves Modulation of the Indoleamine-2,3-Dioxygenase-1 Pathway and Salivary Microbiome
McDew-White et al., EBioMedicine. 2021.
https://pubmed.ncbi.nlm.nih.gov/34954656/
HIV-associated periodontal disease (PD) affects people living with HIV (PLWH) on combination anti-retroviral therapy (cART). Researchers used a systems biology approach to investigate the molecular, metabolome, and microbiome changes underlying PD and its modulation by phytocannabinoids (Δ9-THC) in rhesus macaques. Δ9-THC reduced IDO1 protein expression. The findings suggest that phytocannabinoids may help reduce gingival/systemic inflammation, salivary dysbiosis, and potentially metabolic disease in PLWH on cART. Supported by ORIP (P51OD011104, P51OD011133, U42OD010442), NIAID, NIDA, NIDDK, NIDCR, and NIMH.
Dynamics and Origin of Rebound Viremia in SHIV-Infected Infant Macaques Following Interruption of Long-Term ART
Obregon-Perko et al., JCI Insight. 2021.
https://pubmed.ncbi.nlm.nih.gov/34699383/
Animal models that recapitulate human COVID-19 disease are critical for understanding SARS-CoV-2 viral and immune dynamics, mechanisms of disease, and testing of vaccines and therapeutics. A group of male pigtail macaques (PTMs) were euthanized either 6- or 21-days after SARS-CoV-2 viral challenge and demonstrated mild-to-moderate COVID-19 disease. Pulmonary infiltrates were dominated by T cells, virus-targeting T cells were predominantly CD4+, increases in circulating inflammatory and coagulation markers, pulmonary pathologic lesions, and the development of neutralizing antibodies were observed. Collectively, the data suggests PTMs are a valuable model to study COVID-19 pathogenesis and may be useful for testing vaccines and therapeutics. Supported by ORIP (P51OD011104) and NIAID.
Antiretroviral Therapy Timing Impacts Latent Tuberculosis Infection Reactivation in a Tuberculosis/Simian Immunodeficiency Virus Coinfection Model
Sharan et al., Journal of Clinical Investigation. 2021.
https://pubmed.ncbi.nlm.nih.gov/34855621/
In the rhesus macaque model for Mycobacterium tuberculosis plus simian immunodeficiency virus (SIV) co-infection, chronic immune activation rather than depletion of CD4+ T cells correlates with reactivation of latent tuberculosis infection (LTBI). Researchers administered combined antiretroviral therapy (cART) at 2 weeks post-SIV co-infection to study whether restoration of CD4+ T cell immunity occurred more broadly, and whether this prevented LTBI compared to cART initiated at 4 weeks post-SIV. Earlier initiation of cART enhanced survival led to better control of viral replication and reduced immune activation in the periphery and lung vasculature, thereby reducing the rate of SIV-induced reactivation. Supported by ORIP (K01OD031898, P51OD011133, P51OD011132, S10OD028653) and NIAID.
CD4+ T Cells Are Dispensable for Induction of Broad Heterologous HIV Neutralizing Antibodies in Rhesus Macaques
Sarkar et al., Frontiers in Immunology. 2021.
https://www.frontiersin.org/articles/10.3389/fimmu.2021.757811/full
Researchers investigated the humoral response in vaccinated rhesus macaques with CD4+ T cell depletion, using the VC10014 DNA protein co-immunization vaccine platform (with gp160 plasmids and gp140 trimeric proteins derived from an HIV-1 infected subject). Both CD4+-depleted and non-depleted animals developed comparable Tier 1 and 2 heterologous HIV-1 neutralizing plasma antibody titers. Thus, primates generate HIV neutralizing antibodies in the absence of robust CD4+ T cell help, which has important implications for vaccine development. Supported by ORIP (P51OD011092, P40OD028116, U42OD023038, U42OD010426), NIAID, and NIDCR.