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Vanderford, T. H.

Publications and source records attributed to Vanderford, T. H..

3 recordsLinked to original sources

TREM2+ and interstitial macrophages orchestrate airway inflammation in SARS-CoV-2 infection in rhesus macaques

The COVID-19 pandemic remains a global health crisis, yet, the immunopathological mechanisms driving the development of severe disease remain poorly defined. Here, we utilize a rhesus macaque (RM) model of SARS-CoV-2 infection to delineate perturbations in the innate immune system during acute infection using an integrated systems analysis. We found that SARS-CoV-2 initiated a rapid infiltration (two days post infection) of plasmacytoid dendritic cells into the lower airway, commensurate with IFNA production, natural killer cell activation, and induction of interferon-stimulated genes. At this early interval, we also observed a significant increase of blood CD14-CD16+ monocytes. To dissect the contribution of lung myeloid subsets to airway inflammation, we generated a novel compendium of RM-specific lung macrophage gene expression using a combination of sc-RNA-Seq data and bulk RNA-Seq of purified populations under steady state conditions. Using these tools, we generated a longitudinal sc-RNA-seq dataset of airway cells in SARS-CoV-2-infected RMs. We identified that SARS-CoV-2 infection elicited a rapid recruitment of two subsets of macrophages into the airway: a C206+MRC1-population resembling murine interstitial macrophages, and a TREM2+ population consistent with CCR2+ infiltrating monocytes, into the alveolar space. These subsets were the predominant source of inflammatory cytokines, accounting for ~75% of IL6 and TNF production, and >90% of IL10 production, whereas the contribution of CD206+MRC+ alveolar macrophages was significantly lower. Treatment of SARS-CoV-2 infected RMs with baricitinib (Olumiant(R)), a novel JAK1/2 inhibitor that recently received Emergency Use Authorization for the treatment of hospitalized COVID-19 patients, was remarkably effective in eliminating the influx of infiltrating, non-alveolar macrophages in the alveolar space, with a concomitant reduction of inflammatory cytokines. This study has delineated the major subsets of lung macrophages driving inflammatory and anti-inflammatory cytokine production within the alveolar space during SARS-CoV-2 infection. One sentence summaryMulti-omic analyses of hyperacute SARS-CoV-2 infection in rhesus macaques identified two population of infiltrating macrophages, as the primary orchestrators of inflammation in the lower airway that can be successfully treated with baricitinib

microbiology

Baricitinib treatment resolves lower airway inflammation and neutrophil recruitment in SARS-CoV-2-infected rhesus macaques

Effective therapeutics aimed at mitigating COVID-19 symptoms are urgently needed. SARS-CoV-2 induced hypercytokinemia and systemic inflammation are associated with disease severity. Baricitinib, a clinically approved JAK1/2 inhibitor with potent anti-inflammatory properties is currently being investigated in COVID-19 human clinical trials. Recent reports suggest that baricitinib may also have antiviral activity in limiting viral endocytosis. Here, we investigated the immunologic and virologic efficacy of baricitinib in a rhesus macaque model of SARS-CoV-2 infection. Viral shedding measured from nasal and throat swabs, bronchoalveolar lavages and tissues was not reduced with baricitinib. Type I IFN antiviral responses and SARS-CoV-2 specific T cell responses remained similar between the two groups. Importantly, however, animals treated with baricitinib showed reduced immune activation, decreased infiltration of neutrophils into the lung, reduced NETosis activity, and more limited lung pathology. Moreover, baricitinib treated animals had a rapid and remarkably potent suppression of alveolar macrophage derived production of cytokines and chemokines responsible for inflammation and neutrophil recruitment. These data support a beneficial role for, and elucidate the immunological mechanisms underlying, the use of baricitinib as a frontline treatment for severe inflammation induced by SARS-CoV-2 infection.

immunology

Microbiome Stability with Chronic SIV Infection in AIDS-resistant Sooty Mangabeys

Sooty mangabeys (SMs) are a natural host species of simian immunodeficiency virus (SIV) and avoid acquired immune deficiency syndrome (AIDS) despite persistently high viral loads, making them a pivotal research model for HIV pathogenesis. Unlike pathogenic SIV infection of macaque species, or HIV infection of humans, SIV-infected SMs maintain gastrointestinal barrier integrity. Here, we characterize the gastrointestinal bacterial microbiota of SIV-infected and uninfected SMs and perform a comparative analysis of diet-matched, rhesus macaques (RM). We assessed the fecal microbiome in fifty SM and thirty RM in total, and conducted analyses of the effect of SIV-status, species, and housing. When examining indoor-outdoor and indoor-only housing in our SM cohorts, biodiversity reduction and mild phylogenetic taxonomic perturbances were present. No statistically relevant differences were seen for biodiversity richness and evenness, or phylogenetic taxonomic communities between SIV negative and positive SM cohorts. In contrast, with pathogenic early chronic SIV infections in RM a trend of alpha diversity loss and increase of beta diversity and few phyla taxonomic communities differed. Lastly, we observed lower levels of pathobiont bacterial communities in SIV-uninfected SMs relative to RMs. These data suggest that the pre-existing bacterial community structure may contribute to the divergent phenotype between SIV natural hosts and pathogenic macaque species.\n\nImportanceHuman immunodeficiency virus remains a global concern. The sooty mangabey (SM) monkey is an important biomedical research model for understanding HIV pathogenesis due to its ability to avoid AIDS disease progression despite high viremia. In people living with HIV, gastrointestinal dysbiosis towards enrichment of pathobiont communities has been frequently reported. In this study we characterized the fecal microbiota of a primate non-pathogenic SIV host, the SM, and made direct comparisons to a pathogenic SIV host species, the rhesus macaque. We observed that SMs exhibit stability of the microbiota community into chronic SIV infection, which contrasts with SIV-infected rhesus macaques, in which we observed bacterial community divergence relative to uninfected animals. Collectively, our observation of stabilization of beneficent taxa in the mucosa of AIDS-resistant primates suggests that therapeutic strategies to enrich these communities may have potential for ameliorating the gastrointestinal inflammation in people living with HIV.

immunology