Abstract: An in vitro study was performed to elucidate the possible role of interleukin-1α(IL-1α) and IL-6 in the interaction between keratinocytes and dermal fibroblasts and the regulatory effects of prostaglandin E₁(PGE₁). The results showed that IL-1α was mainly produced by keratinocytes and IL-6 mainly by dermal fibroblasts. Conditioned media from dermal fibroblasts stimulated the proliferation of keratinocytes, and to a less extent vice versa. PGE₁ and recombinant IL-1α enhanced IL-6 production in dermal fibroblasts. However, recombinant IL-6 had little effects on IL-1α production in keratinocytes. Anti IL-6 antibody inhibited the proliferation of keratinocytes grown in fibroblast derived conditioned media, suggesting that IL-6 is a major factor responsible for the growth-promoting effect of the conditioned media. These results suggest that IL-1α and IL-6 are important mediators in the interaction between epidermis and dermis.

Key words: IL-1α, IL-6, Keratinocyte, Fibroblast