GZMB and COVID-19: At a first sight, the radar plots depicted in Figure 2A, showed that, during the first and second wave of SARS-CoV-2 infection, cells expressing molecules associated with cytotoxicity such as Granzyme B (GZMB) and CD107a were more frequent in both Tconv and Treg populations from COVID-19 patients, as also were molecules linked to exhaustion such as CD39 and PD-1 (35), than in those from HD (Figure 2A).