For this study, 79 individuals who had SARS-CoV-2 infection confirmed by positive RT-qPCR in nasopharyngeal smear or positive serology for IgM were recruited and divided into different cohorts depending on the severity of the infection and according to WHO classification (1): Mild (n=20), Severe (n=20), and Critical (n=20) COVID-19, and PCC (n=19). Here, CD40LG is linked to COVID-19.