Granulocyte colony stimulating activity derived from human keratinocytes.

Human keratinocytes are known to produce a variety of soluble mediators including epidermal cell-derived thymocyte activating factor (ETAF), which is closely related, if not identical, to interleukin (IL)-1. In the present studies, crude supernatants derived from normal keratinocytes or from the skin squamous cell carcinoma line, COLO-16, were harvested after 5 days of culture or were purified sequentially by ultrafiltration, Sephadex G-100 …