JUXTACRINE STIMULATION OF CYTOKINE PRODUCTION IN COCULTURES OF HUMAN DERMAL FIBROBLASTS AND T-CELLS

Adhesion of T cells to fibroblasts activates cells to produce cytokine s, either by direct cell contact and/or soluble factors, A cell-associ ated form of IL-1 beta on fibroblasts might act through a cell contact mediated fashion, To test this hypothesis we analysed the activation of T cells and human dermal fibroblasts (HDF) in coculture experiments , Elevated levels of IL-1 beta, secreted by T cells as well as IL-6 an d IL-8, mainly produced by HDF, were found in supernatant fluids of co cultured cells, IL-1 beta mRNA expression was induced in T cells as we ll as in HDF. While in HDF IL-1 beta remained cell-associated, T cells were activated to produce and secrete soluble IL-1 beta and IL-6, IL- 1 beta and possibly other soluble factors increased IL-6 production by fibroblasts, These effects could be mainly attributed to CD8(+) T cel ls, Our results suggest, that IL-1 beta, produced as a cell-associated cytokine by human dermal fibroblasts, acts as a juxtacrine molecule t o stimulate T cells, Such a cellular cooperation, could be a powerful mediator in inflammatory response and possibly in wound healing. (C) 1 996 Academic Press Limited