Selected Grantee Publications
Lymphoid Tissues Contribute to Plasma Viral Clonotypes Early After Antiretroviral Therapy Interruption in SIV-Infected Rhesus Macaques
Solis-Leal et al., Science Translational Medicine. 2023.
https://pubmed.ncbi.nlm.nih.gov/38091409/
Researchers are interested in better understanding the sources, timing, and mechanisms of HIV rebound that occurs after interruption of antiretroviral therapy (ART). Using rhesus macaques (sex not specified), investigators tracked barcoded simian immunodeficiency virus (SIV) clonotypes over time and among tissues. Among the tissues studied, mesenteric lymph nodes, inguinal lymph nodes, and spleen contained viral barcodes detected in plasma. Additionally, the authors reported that CD4+ T cells harbored the most viral RNA after ART interruption. These tissues are likely to contribute to viral reactivation and rebound after ART interruption, but further studies are needed to evaluate the relative potential contributions from other tissues and organs. Supported by ORIP (P51OD011104, P51OD011133, S10OD028732, S10OD028653), NCI, NIMH, and NINDS.
Broad Receptor Tropism and Immunogenicity of a Clade 3 Sarbecovirus
Lee et al., Cell Host and Microbe. 2023.
https://www.sciencedirect.com/science/article/pii/S1931312823004225
Investigators showed that the S glycoprotein of the clade 3 sarbecovirus PRD-0038 in the African Rhinolophus bat has a broad angiotensin-converting enzyme 2 (ACE2) usage and that receptor-binding domain (RBD) mutations further expand receptor promiscuity and enable human ACE2 utilization. They generated a cryogenic electron microscopy structure of the RBD bound to ACE2, explaining receptor tropism and highlighting differences between SARS-CoV-1 and SARS-CoV-2. PRD‑0038 S vaccination elicits greater titers of antibodies cross-reacting with vaccine-mismatched clade 2 and clade 1a sarbecoviruses, compared with SARS-CoV-2. These findings underline a potential molecular pathway for zoonotic spillover of a clade 3 sarbecovirus, as well as the need to develop pan-sarbecovirus vaccines and countermeasures. Supported by ORIP (S10OD032290, S10OD026959, S10OD021644), NIAID, NCI, and NIGMS.
DAZL Knockout Pigs as Recipients for Spermatogonial Stem Cell Transplantation
Lara et al., Cells. 2023.
https://pubmed.ncbi.nlm.nih.gov/37947660/
Spermatogonial stem cell (SSC) transplantation is a technique that holds potential for addressing male infertility, as well as generation of genetically modified animal models. DAZL (Deleted in Azoospermia–Like) is a conserved RNA-binding protein important for germ cell development, and DAZL knockout (KO) causes defects in germ cell commitment and differentiation. Investigators characterized DAZL-KO pigs as SSC transplantation recipients. DAZL-KO pigs support donor-derived spermatogenesis following SSC transplantation, but low spermatogenic efficiency currently limits their use for the production of offspring. Supported by ORIP (R01OD016575) and NIGMS.
The Power of the Heterogeneous Stock Rat Founder Strains in Modeling Metabolic Disease
Wagner et al., Endocrinology. 2023.
https://pubmed.ncbi.nlm.nih.gov/37882530/
Metabolic diseases are a host of complex conditions, including obesity, diabetes mellitus, and metabolic syndrome. Endocrine control systems (e.g., adrenals, thyroid, gonads) are causally linked to metabolic health outcomes. In this study, investigators determined novel metabolic and endocrine health characteristics in both sexes of six available substrains similar to the N/NIH Heterogeneous Stock (HS) rat founders. This deep-phenotyping protocol provides new insight into the exceptional potential of the HS rat population to model complex metabolic health states. The following hypothesis was tested: The genetic diversity in the HS rat founder strains represents a range of endocrine health conditions contributing to the diversity of cardiometabolic disease risks exhibited in the HS rat population. Supported by ORIP (R24OD024617), NHLBI, NIGMS and NIDDK.
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.
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
Increased Collective Migration Correlates With Germline Stem Cell Competition in a Basal Chordate
Fentress and De Tomaso et al., PLOS One. 2023.
https://pubmed.ncbi.nlm.nih.gov/37903140/
Cell competition is a process that compares the relative fitness of progenitor cells and results in healthier cells, contributing a higher proportion to the final tissue composition. Investigators are studying cell competition in a novel model organism, the colonial ascidian, Botryllus schlosseri. They demonstrated that winner germline stem cells show enhanced migratory ability to chemotactic cues ex vivo and that enhanced migration correlates with both expression of the Notch ligand, Jagged, and cluster size. The ability to study conserved aspects of cell migration makes Botryllus an excellent model for future studies on competition, chemotaxis, and collective cell migration. Supported by ORIP (R21OD030520) and NIGMS.
Enhanced IL-17 Producing and Maintained Cytolytic Effector Functions of Gut Mucosal CD161+ CD8+ T Cells in SIV-Infected Rhesus Macaques
Thirugnanam et al., Viruses. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10535321/
HIV infection is associated with the depletion of CD161-expressing CD4+ Th17 cells, but the effects on other IL-17–producing T cell subsets are not understood fully. Researchers characterized the functions of non-invariant CD161-expressing CD8+ T cell subpopulations in peripheral blood and mucosal tissues of rhesus macaques (sex not specified) during chronic simian immunodeficiency virus (SIV) infection. They demonstrated that cell frequencies and function were unaffected by infection, but enhanced IL-17 production capacity and sustained Th1-type and cytolytic functions were observed. This work suggests that CD161-expressing CD8+ T cells might have important functions in gut mucosal immunity during chronic HIV infection. Supported by ORIP (P51OD011104, S10OD026800), NIAID, NIDDK, and NIMH.
A Gut-Restricted Glutamate Carboxypeptidase II Inhibitor Reduces Monocytic Inflammation and Improves Preclinical Colitis
Peters et al., Science Translational Medicine. 2023.
https://www.science.org/doi/10.1126/scitranslmed.abn7491
Many patients with moderate-to-severe inflammatory bowel disease (IBD) do not have adequate disease control, and glutamate carboxypeptidase II (GCPII) offers a promising target for therapeutic development. Researchers generated a class of GCPII inhibitors. They demonstrated that the inhibitor reduced monocytic inflammation in mice and protected against the loss of barrier integrity in primary human colon epithelial air–liquid interface monolayers. Their findings suggest that local inhibition of GCPII could be applied for the development of IBD therapeutics. Supported by ORIP (K01OD030517, T32OD011089), NIGMS, and NCCIH.
Antiretroviral Therapy Ameliorates Simian Immunodeficiency Virus–Associated Myocardial Inflammation by Dampening Interferon Signaling and Pathogen Response in the Heart
Robinson et al., The Journal of Infectious Diseases. 2023.
https://doi.org/10.1093/infdis/jiad105
HIV is associated with increased risk of cardiovascular disease, but the underlying mechanisms are not fully understood. Using RNA sequencing, investigators characterized the effects of simian immunodeficiency virus (SIV) infection on the hearts of male rhesus macaques. They demonstrated that SIV infection drives a canonical antiviral response in the heart, as well as dysregulation of genes involved in fatty acid shuttling and metabolism. Their findings suggest that antiretroviral therapy helps mitigate immune activation during viremic conditions and plays a cardioprotective role. Future studies are needed to assess the long-term effects of these dynamics. Supported by ORIP (P51OD011104), NIAID, NIMH, and NINDS.