Selected Grantee Publications
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.
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.
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.
Genome Structures Resolve the Early Diversification of Teleost Fishes
Parey et al., Science. 2023.
https://pubmed.ncbi.nlm.nih.gov/36758078/
The early evolution of teleost fishes remains an unanswered question among evolutionary biologists. The three earliest branching clades of crown teleosts are Elopomorpha (e.g., tarpons, eels), Osteoglossomorpha (e.g., arapaima, elephantnose fish), and Clupeocephala (e.g., zebrafish, medaka). Building on recently described genome assemblies in Elopomorpha, the authors explored teleost phylogeny using independent gene sequencing and chromosomal rearrangement phylogenomic approaches. They found that Elopomorpha and Osteoglossomorpha comprise a monophyletic sister group to all other teleosts. This report highlights the value of combining different levels of genome-wide information to solve complex phylogenies and will serve as a basis for new investigations into the genomic and functional evolution of teleosts. Supported by ORIP (R01OD011116).
Promoting Validation and Cross-Phylogenetic Integration in Model Organism Research
Cheng et al., Disease Models & Mechanisms. 2022.
https://www.doi.org/10.1242/dmm.049600
Model organisms are essential for biomedical research and therapeutic development, but translation of such research to the clinic is low. The authors summarized discussions from an NIH virtual workshop series, titled “Validation of Animal Models and Tools for Biomedical Research,” held from 2020 to 2021. They described challenges and opportunities for developing and integrating tools and resources and provided suggestions for improving the rigor, validation, reproducibility, and translatability of model organism research. Supported by ORIP (R01OD011116, R24OD031447, R03OD030597, R24OD018559, R24OD017870, R24OD026591, R24OD022005, U42OD026645, U42OD012210, U54OD030165, UM1OD023221, P51OD011107), NIAMS, NIDDK, NIGMS, NHGRI, and NINDS.
X Chromosome Agents of Sexual Differentiation
Arnold et al., Nature Reviews Endocrinology. 2022.
https://www.doi.org/10.1038/s41574-022-00697-0
Many diseases affect one sex disproportionately. A major goal of biomedical research is to understand which sex-biasing factors influence disease severity and to develop therapeutic strategies to target these factors. Two groups of such agents are sex chromosome genes and gonadal hormones. Researchers use the “four core genotypes” model to enable comparisons among animals with different sex chromosomes but the same type of sex hormones, which allows investigators to distinguish disease mechanisms influenced by the sex chromosomes. Supported by ORIP (R01OD030496, R21OD026560), NICHD, NIDDK, and NHLBI.
Metabolic Transitions Define Spermatogonial Stem Cell Maturation
Voigt et al., Human Reproduction. 2022.
https://www.doi.org/10.1093/humrep/deac157
The spermatogonial stem cell (SSC) is the basis of male fertility. One potential option to preserve fertility in patients treated with anti-cancer therapy is isolation and laboratory culture of the juvenile SSC pool with subsequent transplantation to restore spermatogenesis. However, efficient culture of undifferentiated spermatogonia, including SSCs, in mammals other than rodents remains challenging. Investigators reported that the metabolic phenotype of prepubertal human spermatogonia is distinct from that of adult spermatogonia and that SSC development is characterized by specific metabolic transitions from oxidative phosphorylation to anaerobic metabolism. Supported by ORIP (R01OD016575) and NICHD.
Evolution of the Nitric Oxide Synthase Family in Vertebrates and Novel Insights in Gill Development
Annona et al., Proceedings of the Royal Society B. 2022.
https://www.doi.org/10.1098/rspb.2022.0667
Nitric oxide (NO) plays essential roles in biological systems, including cardiovascular homeostasis, neurotransmission, and immunity. Knowledge of NO synthases (NOS) is substantial, but the origin of nos gene orthologues in fishes, with respect to tetrapods, remains largely unknown. The recent identification of nos3 in the spotted gar, considered lost in this lineage, prompted the authors to explore nos gene evolution. Here, they report that nos2 experienced several lineage-specific gene duplications and losses. Additionally, nos3 was found to be lost independently in two teleost lineages, Elopomorpha and Clupeocephala. Further, the expression of at least one nos paralogue in gills of developing shark, bichir, sturgeon, and gar, but not in gills of lamprey, suggests nos expression in the gill might have arisen in the last common ancestor of gnathostomes. These results provide a framework for further research on the role of nos genes. Supported by ORIP (P40OD019794, R01OD011116).
Safety and Antiviral Activity of Triple Combination Broadly Neutralizing Monoclonal Antibody Therapy Against HIV-1: A Phase 1 Clinical Trial
Julg et al., Nature Medicine. 2022.
https://www.doi.org/10.1038/s41591-022-01815-1
Previous evidence suggests that at least three broadly neutralizing antibodies (bNAbs) targeting different epitope regions are needed for robust treatment and control of HIV. The investigators evaluated the safety, tolerability, and pharmacokinetics of PGDM1400, an HIV-1 V2-glycan–specific antibody, in a first-in-human trial. The primary endpoints were safety, tolerability, pharmacokinetics, and antiviral activity. The trial met the prespecified endpoints in male and female adults. These data will help advance understanding of the capabilities, limitations, and future role of bNAb combinations in HIV prevention and care. Supported by ORIP (R01OD024917), NIAID, and NCATS.