A longitudinal study looking at the kinetics of antibodies directed against the spike protein in patients with COVID-19 found that IgA antibodies were produced in the first week of the infection and peaks after 20–22 days, whereas IgM antibodies titers reached a peak level after 10–12 days and subsequently started to disappear 18 days after the onset of symptoms (131). Here, CD40LG is linked to COVID-19.