CD40LG and COVID-19: Furthermore, using the developed ELISAs, we evaluated the production of SARS-CoV-2 specific IgG and IgM antibodies in a cohort of hospitalized COVID-19 patients (n = 52), including samples collected during the 1st week (n = 10), 2nd week (n = 23), 3rd week (n = 14) or 4th week (n = 5) of symptoms-onset.