We next compared the TCRB complementarity-determining region 3 (CDR3β) length of PNS-myelin-reactive clonotypes from CD4+ T cells (n = 166) with the SARS-CoV-2-specific ones (n = 92) from post-COVID-19 patients with GBS or with those of microbe-reactive CFSElow fractions from healthy donors27,28. This evidence concerns the gene CD4 and COVID-19.