Selected Grantee Publications
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- 172 results found
- HIV/AIDS
- Microbiome
Antiretroviral Therapy Reveals Triphasic Decay of Intact SIV Genomes and Persistence of Ancestral Variants
Fray et al., Cell Host & Microbe. 2023.
https://doi.org/10.1016/j.chom.2023.01.016
Antiretroviral therapy (ART) halts HIV-1 replication but is not curative; a pool of latently infected CD4+ T cells persists, and viremia rapidly rebounds if ART is stopped. Using an intact proviral DNA assay, researchers characterized quantitative and qualitative changes in CD4+ T cells for 4 years following ART initiation in rhesus macaques of both sexes. They found that viruses replicating at ART initiation had mutations conferring antibody escape, and sequences with large numbers of antibody escape mutations became less abundant at later time points. Together, these findings reveal that the population of simian immunodeficiency virus (SIV)–infected CD4+ T cells is dynamic and provide a framework for evaluating and interpreting intervention trials. Supported by ORIP (R01OD011095), NIAID, and NIDCR.
IL-21-IgFc Immunotherapy Alters Transcriptional Landscape of Lymph Node Cells Leading to Enhanced Flu Vaccine Response in Aging and SIV Infection
Pallikkuth et al., Aging Cell. 2023.
https://pubmed.ncbi.nlm.nih.gov/37712598/
Aging is associated with increased risk of seasonal flu disease burden and serious flu-related complications, particularly for people with HIV. In this study, investigators aimed to elucidate the immunomodulation following flu vaccination in aging male and female rhesus macaques infected with simian immunodeficiency virus (SIV). Their results suggest that IL-21 treatment at the time of flu vaccination modulates the inductive lymph node germinal center activity to reverse SIV-associated immune dysfunction. The authors identified IL-21 as a potential candidate molecule for immunotherapy to enhance flu vaccine responses in affected populations. Further studies could examine the overall benefit of IL-21 immunotherapy on mucosal lung immunity and protection against infection. Supported by ORIP (R24OD010947), NIA, and NIAID.
Intradermal but Not Intramuscular Modified Vaccinia Ankara Immunizations Protect Against Intravaginal Tier2 Simian–Human Immunodeficiency Virus Challenges in Female 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.
Tenth Aquatic Models of Human Disease Conference 2022 Workshop Report: Aquatics Nutrition and Reference Diet Development
Sharpton et al., Zebrafish. 2023.
https://pubmed.ncbi.nlm.nih.gov/38117219/
Standard reference diets (SRDs) for aquatic model organisms, vital for supporting scientific rigor and reproducibility, are yet to be adopted. At this workshop, the authors presented findings from a 7-month diet test study conducted across three aquatic research facilities: Zebrafish International Resource Center (University of Oregon), Kent and Sharpton laboratories (Oregon State University), and Xiphophorus Genetic Stock Center (Texas State University). They compared the effects of two commercial diets and a suggested zebrafish SRD on general fish husbandry, microbiome composition, and health in three fish species (zebrafish, Xiphophorus, and medaka), and three zebrafish wild-type strains. They reported outcomes, gathered community feedback, and addressed the aquatic research community's need for SRD development. Discussions underscored the influence of diet on aquatic research variability, emphasizing the need for SRDs to control cross-experiment and cross-laboratory reproducibility. Supported by ORIP (P40OD011021, R24OD011120, and R24OD010998) and NICHD.
Host Immunity Associated With Spontaneous Suppression of Viremia in Therapy-Naïve Young Rhesus Macaques Following Neonatal SHIV Infection
Evangelous et al., Journal of Virology. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10688376/
Previously, investigators developed a pediatric rhesus macaque model for simian–human immunodeficiency virus infection that can be exploited to identify host immunity associated with viremia suppression. In the present study, they used the model (with male and female animals) to characterize humoral and cellular immunity and plasma biomarkers associated with spontaneous viremia suppression. They identified CD8-expressing cells and varied T-cell subsets that were associated with viremia suppression. Additionally, the authors observed intermediate monocytes with upregulation of inhibitory genes that previously had been reported only in cytotoxic cells. These findings suggest a complex immunologic milieu of viremia suppression in pediatric populations. Supported by ORIP (P51OD011092, U42OD010426) and NIAID.
Conjugation of HIV-1 Envelope to Hepatitis B Surface Antigen Alters Vaccine Responses in Rhesus Macaques
Nettere et al., NPJ Vaccines. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10673864/
Researchers are interested in developing an HIV-1 vaccine that improves upon the regimen used in the RV144 clinical trial. The authors tested the hypothesis that a conjugate vaccine based on the learned response to immunization with hepatitis B virus could be utilized to expand T-cell help and improve antibody production against HIV-1. Using juvenile rhesus macaques of both sexes, they evaluated the immunogenicity of their conjugate regimen. Their findings suggest that conjugate vaccination can engage both HIV-1 Env– and hepatitis B surface antigen–specific Tcell help and modify antibody responses at early time points. This work may help inform future efforts to improve the durability and efficacy of next-generation HIV vaccines. Supported by ORIP (P51OD011107, K01OD024877) and NIAID.
A Combined Adjuvant Approach Primes Robust Germinal Center Responses and Humoral Immunity in Non-Human Primates
Phung et al., Nature Communications. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10625619/
Protein antigens require adjuvants for high immunogenicity, and delivery kinetics are a critical component of rational HIV vaccine design. Investigators employed a combined adjuvant approach (i.e., short phosphoserine peptide linkers that promote tight binding to aluminum hydroxide, plus saponin/MPLA nanoparticles) with slow antigen delivery and potent immune-stimulating complexes in rhesus macaques of both sexes. They reported that pSer-modified antigen shifts immunodominance to allow subdominant epitope-targeting of rare B cells. These findings indicate that a combined adjuvant approach can augment humoral immunity by modulating immunodominance, and this work can be applied for the development of clinical therapeutics. Supported by ORIP (P51OD011104) and NIAID.
Intravenous Bacille Calmette–Guérin Vaccination Protects Simian Immunodeficiency Virus–Infected Macaques From Tuberculosis
Larson et al., Nature Microbiology. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10627825/
People with HIV are susceptible to developing tuberculosis and experiencing associated complications. Researchers assessed the safety, immunogenicity, and efficacy of intravenous Bacille Calmette–Guérin vaccination in male and female cynomolgus macaques coinfected with simian immunodeficiency virus (SIV) and Mycobacterium tuberculosis. The vaccine conferred protection in all vaccinated SIV-naive animals and in 9 of 12 vaccinated SIV-infected animals. These data suggest that the vaccine is immunogenic and efficacious in SIV-infected animals. Overall, this work establishes a model to identify correlates of protection, and these findings can be applied in future studies to develop effective vaccine regimens for people with HIV. Supported by ORIP (P51OD011106, R01OD01033539) and NIAID.
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.
High Throughput Analysis of B Cell Dynamics and Neutralizing Antibody Development During Immunization With a Novel Clade C HIV-1 Envelope
Mopuri et al., PLoS Pathogens. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10627474/
Broadly neutralizing antibodies from chronic infection are an area of interest for HIV-1 vaccine development. Using male and female rhesus macaques, a team of researchers conducted a high-throughput longitudinal study to determine how B cells respond to vaccines expressing different HIV-1 Env immunogens. In most animals, the B cells failed to achieve neutralizing activity. One animal, however, developed neutralizing antibodies against the vaccine strain. These data suggest that early elicitation might favor the induction of neutralizing antibodies against HIV-1 Env. This work offers new insights for autologous neutralizing antibody lineages. Supported by ORIP (P51OD011132, S10OD026799) and NIAID.