This is in agreement with previous studies showing that IL‐6 per se promotes human keratinocyte proliferation in vitro and that ectopic IL‐6 expression in rat skin via naked DNA transfection induces keratinocyte proliferation, as well as lymphocytic infiltration and erythema (Grossman et al, 1989; Yoshizaki et al, 1990; Sawamura et al, 1998). This evidence concerns the gene IL6 and Erythema.