We measured the serum levels of IgM, IgG, and IgA against the N protein (IgM(N), IgG(N), and IgA(N)), S1 protein (IgM(S1), IgG(S1), and IgA(S1)), and RBD (IgM(RBD), IgG(RBD), and IgA(RBD)) in the serum samples of the COVID-19 patients collected until 12 days after symptom onset. This evidence concerns the gene CD40LG and COVID-19.