TGFB1 and COVID-19–associated multisystem inflammatory syndrome in children: Goetzke C.C. et al. demonstrated that T cell receptor repertoires of patients with MIS-C exhibit an expansion of T cells expressing TCRVβ21.3, resembling EBV-reactive T cell clones; hence, serum TGFβ in patients with MIS-C can trigger EBV reactivation, which is reversible with TGFβ blockade [72].