COVID-19-induced ARDS is associated with decreased frequency of activated memory/effector T cells expressing tissue migration molecule CD11a++

Anft, Moritz; Paniskaki, Krystallenia; Blazquez-Navarro, Arturo; Doevelaar, Adrian; Seibert, Felix S.; Hölzer, Bodo; Skrzypczyk, Sarah; Kohut, Eva; Kurek, Julia; Zapka, Jan; Wehler, Patrizia; Kaliszczyk, Sviatlana; Bajda, Sharon; Thieme, Constantin J.; Roch, Toralf; Konik, Margarethe Justine; Berger, Marc Moritz; Brenner, Thorsten; Kölsch, Uwe; Meister, Toni L.; Pfaender, Stephanie; Steinmann, Eike; Tempfer, Clemens; Watzl, Carsten; Dolff, Sebastian; Dittmer, Ulf; Abou-El-Enein, Mohamed; Westhoff, Timm H.; Witzke, Oliver; Stervbo, Ulrik; Babel, Nina

Preventing the progression to acute respiratory distress syndrome (ARDS) in COVID-19 is an unsolved challenge. The involvement of T cell immunity in this exacerbation remains unclear. To identify predictive markers of COVID-19 progress and outcome, we analyzed peripheral blood of 10 COVID-19-associated ARDS patients and 35 mild/moderate COVID-19 patients, not requiring intensive care. Using multi-parametric flow cytometry, we compared quantitative, phenotypic and functional characteristics of circulating bulk immune cells, and SARS-CoV-2 S-protein reactive T cell between the two groups. ARDS patients demonstrated significantly higher S-protein reactive CD4+ and CD8+ T cells compared to non-ARDS patients. Of interest, comparison of circulating bulk T cells in ARDS patients to non-ARDS patients demonstrated decreased frequencies of CD4+ and CD8+ T cell subsets with activated memory/effector T cells expressing tissue migration molecule CD11a++. Importantly, survival from ARDS (4/10) was accompanied by a recovery of the CD11a++ T cell subsets in peripheral blood. Conclusively, data on S-protein reactive polyfunctional T cells indicate the ability of ARDS patients to generate antiviral protection. Furthermore, decreased frequencies of activated memory/effector T cells expressing tissue migratory molecule CD11a++ observed in circulation of ARDS patients might suggest their involvement in ARDS development and propose CD11a-based immune signature as a possible prognostic marker.