Selected Grantee Publications
- Clear All
- 244 results found
- Microbiome
- Vaccines/Therapeutics
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.
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.
Spontaneous HIV Expression During Suppressive ART Is Associated With the Magnitude and Function of HIV-Specific CD4+ and CD8+ T Cells
Dubé et al., Cell Host Microbe. 2023.
https://linkinghub.elsevier.com/retrieve/pii/S1931-3128(23)00331-1
CD4+ and CD8+ T cells are essential in the control of simian immunodeficiency virus and HIV infections, but the mechanisms are not understood fully. Using multiplexed single-cell RNAflow-fluorescence in situ hybridization, researchers quantified and phenotyped viral reservoirs spontaneously expressing viral RNA and the p24 protein in primary clinical samples from men. They reported associations between active reservoirs and HIV-specific CD4+ and CD8+ T cells, and the active reservoirs were largely dominated by defective proviruses. Their findings suggest that viral reservoirs maintain HIV-specific responses during suppressive antiretroviral therapy (ART), and low-level viral gene expression by spontaneous reservoirs is sufficient to maintain anti-HIV adaptive immunity. Supported by ORIP (P51OD011092) 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.
The Latent Reservoir of Inducible, Infectious HIV-1 Does Not Decrease Despite Decades of Antiretroviral Therapy
McMyn et al., The Journal of Clinical Investigation. 2023.
https://www.doi.org/10.1172/JCI171554
Antiretroviral therapy (ART) does not eliminate the latent HIV reservoir, but it is unknown whether sustained reservoir decay occurs with long-term ART. Researchers used a quantitative viral outgrowth assay, an intact proviral DNA assay, and proviral sequencing to characterize the latent reservoir in men and women with HIV who had maintained suppression of viral replication on ART for 14 to 27 years. They found that the reservoir decay did not continue with long-term ART. Further studies could provide insight into the mechanism underlying these findings. These results reinforce the need for lifelong ART and indicate that the reservoir remains a major barrier to an HIV-1 cure. Supported by ORIP (R01OD011095), NIAID, and NIDCR.
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.
Baseline Tumor Gene Expression Signatures Correlate With Chemoimmunotherapy Treatment Responsiveness in Canine B Cell Lymphoma
Dittrich et al., PLOS ONE. 2023.
https://pubmed.ncbi.nlm.nih.gov/37624862/
Pet dogs develop spontaneous diffuse large B cell lymphoma (DLBCL), and veterinary clinical trials have been employed to treat canine DLBCL and to inform clinical trials for their human companions. Investigators evaluated gene expression in lymph node aspirates from 18 trial dogs and defined good responders as those who relapsed after 90 days, and poor responders as those who relapsed prior to 90 days. They found increased CCND3 correlated with poor prognosis and increased CD36 correlated with good prognosis, as is observed in humans. These findings identify biomarkers that may help guide the choice of chemoimmunotherapy treatment in dogs. Supported by ORIP (K01OD028268) and NCI.
Intestinal Microbiota Controls Graft-Versus-Host Disease Independent of Donor–Host Genetic Disparity
Koyama et al., Immunity. 2023.
https://pubmed.ncbi.nlm.nih.gov/37480848/
Allogeneic hematopoietic stem cell transplantation is a curative therapy for hematopoietic malignancies and non-malignant diseases, but acute graft-versus-host disease (GVHD) remains a serious complication. Specifically, severe gut GVHD is the major cause of transplant-related mortality. Here, the authors show that genetically identical mice, sourced from different vendors, had distinct commensal bacterial compositions, which resulted in significantly discordant severity in GVHD. These studies highlight the importance of pre-transplant microbiota composition for the initiation and suppression of immune-mediated pathology in the gastrointestinal tract, demonstrating the impact of non-genetic environmental determinants to transplant outcome. Supported by ORIP (S10OD028685), NIA, NCI, and NHLBI.
Assessment of Various Standard Fish Diets on Gut Microbiome of Platyfish Xiphophorus maculatus
Soria et al., Journal of Experimental Zoology Part B. 2023.
https://onlinelibrary.wiley.com/doi/10.1002/jez.b.23218
Diet is an important factor affecting experimental reproducibility and data integration across studies. Reference diets for nontraditional animal models are needed to control diet-induced variation. In a study of the dietary impacts on the gut microbiome, researchers found that switching from a custom diet to a zebrafish diet altered the Xiphophorus gut microbiome. Their findings suggest that diets developed specifically for zebrafish can affect gut microbiome composition and might not be optimal for Xiphophorus. Supported by ORIP (R24OD011120, R24OD031467, P40OD011021) and NCI.