Juxtacrine stimulation of cytokine production in cocultures of human dermal fibroblasts and T cells.
Adhesion of T cells to fibroblasts activates cells to produce cytokines, either by direct cell contact and/or soluble factors. A cell-associated 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 and IL-8, mainly produced by HDF, were found in supernatant fluids of cocultured cells. IL-1 beta mRNA expression was induced in T cells as well 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 cells. Our results suggest, that IL-1 beta, produced as a cell-associated cytokine by human dermal fibroblasts, acts as a juxtacrine molecule to stimulate T cells. Such a cellular cooperation, could be a powerful mediator in inflammatory response and possibly in wound healing.
Department of Pediatrics, University of Berne, Switzerland. spoerri@zmk.unibe.ch
B
B
Spörri
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M
Bickel
A
A
Limat
E R
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Waelti
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Hunziker
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Wiesmann
D018920:Coculture Techniques; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D006801:Humans; D007375:Interleukin-1 / Q000096:biosynthesis*; D015850:Interleukin-6 / Q000096:biosynthesis*; D016209:Interleukin-8 / Q000096:biosynthesis*; D008213:Lymphocyte Activation; D012867:Skin / Q000166:cytology; D013601:T-Lymphocytes / Q000166:cytology / Q000378:metabolism*
D007375:Interleukin-1; D015850:Interleukin-6; D016209:Interleukin-8