Selected Grantee Publications
- Clear All
- 3 results found
- COVID-19/Coronavirus
- HIV/AIDS
- 2020
Responses to Acute Infection with SARS-CoV-2 in the Lungs of Rhesus Macaques, Baboons and Marmosets
Singh et al., Nature Microbiology. 2020.
https://www.nature.com/articles/s41564-020-00841-4
Investigators compared acute SARS-CoV-2 infection in young and old rhesus macaques and baboons. Macaques had clinical signs of viral infection, mild to moderate pneumonitis and extra-pulmonary pathologies; both age groups recovered within 2 weeks. Baboons had prolonged viral RNA shedding and more lung inflammation compared with macaques; inflammation in bronchoalveolar lavage was increased in old versus young baboons. Macaques developed T-cell memory responses and bystander cytokine production. Old macaques had lower titers of SARS-CoV-2-specific IgG antibody levels compared with young macaques. The results indicate macaques and baboons experience acute respiratory distress that recapitulates the progression of COVID-19 in humans. Supported by ORIP (P51OD111033 and U42OD010442) and NIAID.
Imbalance of Regulatory and Cytotoxic SARS-CoV-2-Reactive CD4+ T Cells in COVID-19
Meckiff et al., Cell. 2020.
https://pubmed.ncbi.nlm.nih.gov/33096020/
It is not clear why COVID-19 is deadly in some people and mild in others. To understand the underlying mechanism, investigators studied the contribution of CD4+ T cells in immune responses to SARS-CoV-2 infection. They analyzed single-cell transcriptomic data of >100,000 viral antigen-reactive CD4+ T cells from 40 COVID-19 patients. In hospitalized patients compared to non-hospitalized patients, they found increased proportions of cytotoxic follicular helper cells (TFH) and cytotoxic T helper (TH) cells responding to SARS-CoV-2 and reduced proportion of SARS-CoV-2-reactive regulatory T cells (TREG). Importantly, in hospitalized COVID-19 patients, a strong cytotoxic TFH response was observed early in the illness, which correlated negatively with antibody levels to SARS-CoV-2 spike protein. Polyfunctional TH1 and TH17 cell subsets were underrepresented in the repertoire of SARS-CoV-2-reactive CD4+ T cells compared to influenza-reactive CD4+ T cells. Together, these analyses provided insights into the gene expression patterns of SARS-CoV-2-reactive CD4+ T cells in distinct disease severities. Supported by ORIP (S10RR027366, S10OD025052), NIAID, NHLBI, and NIGMS.
Antiretroviral Therapy Does Not Reduce Tuberculosis Reactivation in a Tuberculosis-HIV Coinfection Model
Ganatra et al., Journal of Clinical Investigation. 2020.
https://www.jci.org/articles/view/136502
Despite treatment of HIV with antiretroviral therapy (ART), the risk of tuberculosis (TB) reactivation is higher in HIV-infected than HIV-uninfected persons. Researchers used Mycobacterium tuberculosis/SIV-coinfected rhesus macaques to model the impact of ART on TB reactivation due to HIV-induced immunosuppression. ART significantly reduced viral loads and increased CD4+ T-cell counts in blood, spleen, and bronchoalveolar lavage samples, but it did not reduce the risk of SIV-induced TB reactivation during the early phase of treatment. This study offers a translational model for the investigation of TB/SIV coinfection and the evaluation of treatment regimens to prevent TB reactivation in HIV-infected individuals. Supported by ORIP (P51OD011133, P51OD011132) and NIAID.