Dysregulated immune profiles have been described in symptomatic patients infected with SARS-CoV-2. Whether the reported immune alterations are specific to SARS-CoV-2 infection or also triggered by other acute illnesses remains unclear. We performed flow cytometry analysis on fresh peripheral blood from a consecutive cohort of (a) patients hospitalized with acute SARS-CoV-2 infection, (b) patients of comparable age and sex hospitalized for another acute disease (SARS-CoV-2 negative), and (c) healthy controls. Using both data-driven and hypothesis-driven analyses, we found several dysregulations in immune cell subsets (e.g., decreased proportion of T cells) that were similarly associated with acute SARS-CoV-2 infection and non–COVID-19-related acute illnesses. In contrast, we identified specific differences in myeloid and lymphocyte subsets that were associated with SARS-CoV-2 status (e.g., elevated proportion of ICAM-1+ mature/activated neutrophils, ALCAM+ monocytes, and CD38+CD8+ T cells). A subset of SARS-CoV-2–specific immune alterations correlated with disease severity, disease outcome at 30 days, and mortality. Our data provide an understanding of the immune dysregulation specifically associated with SARS-CoV-2 infection among acute care hospitalized patients. Our study lays the foundation for the development of specific biomarkers to stratify SARS-CoV-2–positive patients at risk of unfavorable outcomes and to uncover candidate molecules to investigate from a therapeutic perspective.
Rose-Marie Rébillard, Marc Charabati, Camille Grasmuck, Abdelali Filali-Mouhim, Olivier Tastet, Nathalie Brassard, Audrey Daigneault, Lyne Bourbonnière, Sai Priya Anand, Renaud Balthazard, Guillaume Beaudoin-Bussières, Romain Gasser, Mehdi Benlarbi, Ana Carmena Moratalla, Yves Carpentier Solorio, Marianne Boutin, Negar Farzam-kia, Jade Descôteaux-Dinelle, Antoine Philippe Fournier, Elizabeth Gowing, Annemarie Laumaea, Hélène Jamann, Boaz Lahav, Guillaume Goyette, Florent Lemaître, Victoria Hannah Mamane, Jérémie Prévost, Jonathan Richard, Karine Thai, Jean-François Cailhier, Nicolas Chomont, Andrés Finzi, Michaël Chassé, Madeleine Durand, Nathalie Arbour, Daniel E. Kaufmann, Alexandre Prat, Catherine Larochelle