Specialized interferon ligand action in COVID19 (preprint)

The impacts of IFN signaling on COVID19 pathology are multiple, with protective and harmful effects being documented. We report here a multi-omics investigation of IFN signaling in hospitalized COVID19 patients, defining the biosignatures associated with varying levels of 12 different IFN ligands. Previously we showed that seroconversion associates with decreased production of select IFN ligands (Galbraith et al, 2021). We show now that the antiviral transcriptional response in circulating immune cells is strongly associated with a specific subset of ligands, most prominently IFNA2 and IFNG. In contrast, proteomics signatures indicative of endothelial damage associate with levels of IFNB and IFNA6. Differential IFN ligand production is linked to distinct constellations of circulating immune cells. Lastly, IFN ligands associate differentially with activation of the kynurenine pathway, dysregulated fatty acid metabolism, and altered central carbon metabolism. Altogether, these results reveal specialized IFN ligand action in COVID19, with potential diagnostic and therapeutic implications.

Seroconversion stages COVID19 into distinct pathophysiological states (preprint)

COVID19 is a heterogeneous medical condition involving a suite of underlying pathophysiological processes including hyperinflammation, endothelial damage, thrombotic microangiopathy, and end-organ damage. Limited knowledge about the molecular mechanisms driving these processes and lack of staging biomarkers hamper the ability to stratify patients for targeted therapeutics. We report here the results of a cross-sectional multi-omics analysis of hospitalized COVID19 patients revealing that seroconversion status associates with distinct underlying pathophysiological states. Seronegative COVID19 patients harbor hyperactive T cells and NK cells, high levels of IFN alpha, gamma and lambda ligands, markers of systemic complement activation, neutropenia, lymphopenia and thrombocytopenia. In seropositive patients, all of these processes are attenuated, observing instead increases in B cell subsets, emergency hematopoiesis, increased markers of platelet activation, and hypoalbuminemia. We propose that seroconversion status could potentially be used as a biosignature to stratify patients for therapeutic intervention and to inform analysis of clinical trial results in heterogenous patient populations.