CD4 and systemic lupus erythematosus: While CD3+CD4+ T cells proliferated in response to LL37 and cit-LL37 in both SLE and psoriasis, only in SLE a substantial humoral anti-LL37/cit-LL37 response developed9,17,34,35(Fig. 2), suggestive of a preferential expansion of TFH in SLE.