Increased CD95 (Fas) and PD‐1 expression in peripheral blood T lymphocytes in COVID‐19 patients
Silvia Bellesi, Elisabetta Metafuni, Stefan Hohaus, Elena Maiolo, Federica Marchionni, Simone D’Innocenzo, Marilena La Sorda, Manuela Ferraironi, Francesco Ramundo, Massimo Fantoni, Rita Murri, Antonella Cingolani, Simona Sica, Antonio Gasbarrini, Maurizio Sanguinetti, Patrizia Chiusolo, Valerio De Stefano
Abstract
Summary A low count of CD4 + and CD8 + lymphocytes is a hallmark laboratory finding in the coronavirus disease 2019 (COVID‐19). Using flow cytometry, we observed significantly higher CD95 (Fas) and PD‐1 expression on both CD4 + T and CD8 + T cells in 42 COVID‐19 patients when compared to controls. Higher CD95 expression in CD4 + cells correlated with lower CD4 + counts. A higher expression of CD95 in CD4 + and CD8 + lymphocytes correlated with a lower percentage of naive events. Our results might suggest a shift to antigen‐activated T cells, expressing molecules increasing their propensity to apoptosis and exhaustion during COVID‐19 infection.