Selected Grantee Publications
- Clear All
- 51 results found
- Immunology
- U42
Mosaic RBD Nanoparticles Protect Against Challenge by Diverse Sarbecoviruses in Animal Models
Cohen et al., Science. 2022.
https://www.doi.org/10.1126/science.abq0839
Two animal coronaviruses from the SARS-like betacoronavirus (sarbecovirus) lineage—SARS-CoV and SARS-CoV-2—have caused epidemics or pandemics in humans during the past 20 years. New SARS-CoV-2 variants have prolonged the COVID-19 pandemic, and the discovery of diverse sarbecoviruses in bats raises the possibility of another coronavirus pandemic. Vaccines and therapeutics are needed to protect against both SARS-CoV-2 variants and zoonotic sarbecoviruses with the potential to infect humans. The authors designed mosaic-8 nanoparticles (SARS-CoV-2 and seven animal sarbecoviruses) that present randomly arranged sarbecovirus spike receptor-binding domains (RBDs) to elicit antibodies against epitopes that are conserved and relatively occluded rather than variable, immunodominant, and exposed. Their results of immune responses elicited by mosaic-8 RBD nanoparticles in mice and macaques suggest that mosaic nanoparticles could protect against both SARS-CoV-2 variants and zoonotic sarbecoviruses with the potential to infect humans. Supported by ORIP (P40OD012217, U42OD021458, S10OD028685) and NIAID.
Antimicrobial Prophylaxis Does Not Improve Post-Surgical Outcomes in SIV/SHIV–Uninfected or SIV/SHIV–Infected Macaques (Macaca mulatta and Macaca fascicularis) Based on a Retrospective Analysis
Moats et al., PLOS One. 2022.
https://www.doi.org/10.1371/journal.pone.0266616
Some institutions routinely administer antimicrobial prophylaxis to nonhuman primates prior to surgery to prevent surgical site infections. In this study, the investigators assessed the influence of antimicrobial prophylaxis on complication rates in macaques of both sexes receiving peripheral lymph node (PLN) and laparoscopic biopsies. After PLN biopsies, no significant differences were observed between animals that received antimicrobial prophylaxis and those that did not. After laparoscopic biopsies, complication rates were greater in animals that received antimicrobial prophylaxis. Because of these findings, the authors recommend eliminating the use of unnecessary antibiotics in research animals. Supported by ORIP (U42OD023038, P51OD011092).
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.
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.
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.
Limited Expansion of Human Hepatocytes in FAH/RAG2-Deficient Swine
Nelson et al., Tissue Engineering – Part A. 2021.
https://pubmed.ncbi.nlm.nih.gov/34309416/
The mammalian liver's regenerative ability has led researchers to engineer animals as incubators for expansion of human hepatocytes. Nelson et al. engineered immunodeficient swine to support expansion of human hepatocytes and identify barriers to their clinical application. Immunodeficient swine were engineered by knockout of the recombinase-activating gene 2 (RAG2) and fumarylacetoacetate hydrolase (FAH). Immature human hepatocytes (ihHCs) were injected into fetal swine by intrauterine cell transplantation (IUCT) at day 40 of gestation. They identified the mechanism of the eventual graft rejection by the intact NK cell population. They confirmed the presence of residual adaptive immunity in this model of immunodeficiency. Supported by ORIP (U42OD011140).
A Large Repertoire of B Cell Lineages Targeting One Cluster of Epitopes in a Vaccinated Rhesus Macaque
Li et al., Vaccine. 2021.
https://www.sciencedirect.com/science/article/pii/S0264410X21010355?via%3Dihub=
A rhesus macaque that was serially immunized six times with the 8-mer epitope for human monoclonal antibody (mAb) 447-52D—specific to the V3 region of gp120 HIV-1—provided a rare opportunity to study the repertoire of antibodies produced upon vaccination against a particular antigenic site. From a blood sample taken 3 weeks after the last immunization, researchers produced 41 V3-specific recombinant mAbs by single B cell isolation and cloning. Sequence analysis revealed 21 B cell lineages (single and clonally related). The broad repertoire of Abs directed to a small antigenic site shows the targeting potency of a vaccine-elicited immune response in rhesus macaques. Supported by ORIP (P51OD011092, U42OD010246) and NIAID.
Blocking α4β7 Integrin Delays Viral Rebound in SHIVSF162P3-Infected Macaques Treated with Anti-HIV Broadly Neutralizing Antibodies
Frank et al., Science Translational Medicine. 2021.
https://doi.org/10.1126/scitranslmed.abf7201
To explore therapeutic potentials of combining anti-HIV broadly neutralizing antibodies (bNAbs) with α4β7 integrin blockade using the monoclonal antibody Rh-α4β7, investigators treated SHIVSF162P3-infected, viremic macaques with bNAbs only or bNAbs and Rh-α4β7. Treatment with bNAbs alone decreased viremia below 200 copies/ml in eight out of eight macaques, but seven of the monkeys rebounded within 3 weeks. In contrast, three of six macaques treated with both Rh-α4β7 and bNAbs maintained viremia below 200 copies/ml for 21 weeks, whereas three of those monkeys rebounded after 6 weeks. These findings suggest that α4β7 integrin blockade may prolong virologic control by bNAbs in SHIVSF162P3-infected macaques. Supported by ORIP (P51OD011104, U42OD010568, U42OD024282, P40OD028116), NIAID, and NCI.
Protection of Newborn Macaques by Plant-Derived HIV Broadly Neutralizing Antibodies: A Model for Passive Immunotherapy During Breastfeeding
Rosenberg et al., Journal of Virology. 2021.
https://doi.org/10.1128/JVI.00268-21
Preventing vertical transmission of HIV to newborns is an unmet medical need in resource poor countries. Using a breastfeeding macaque model with multiple simian-human immunodeficiency virus challenge, researchers assessed the protective efficacy of two human broadly neutralizing antibodies (bnAbs) against HIV, PGT121 and VRC07-523, which are produced by a plant expression system. Despite the transient presence of plasma viral RNA, the bnAbs prevented productive infection in all newborns with no sustained plasma viremia, compared to viral loads ranging from 103 to 5x108 in four untreated controls. Thus, plant-expressed antibodies show promise as passive immunoprophylaxis in a breastfeeding model in newborns. Supported by ORIP (U42OD023038, P51OD011092) and NIAID.