Furthermore, in addition to effector CD4+ T cell subsets, asthma severity should also be associated with functional impairment of regulatory lymphocyte compartment capable of producing IL‐10, such as T cells that express (Tregs), or not (Tr1), the FoxP3 marker, as well as type 1 regulatory B cells (Br1).19, 20, 21. The gene discussed is CD4; the disease is asthma.