IL-1alpha and IL-6 production by oral and skin keratinocytes: similarities and differences in response to cytokine treatment in vitro

Abstract

IL-1α and IL-6 are important pro-inflammatory and immunomodulatory cytokines and their production by oral (OK) and skin keratinocytes (SK) was compared. OK and SK produced IL-la, but not IL-6, constitutively. TNFα stimulation increased IL-la production by both cell types and exhibited synergy with interferon y (IFNγ). although the latter had no effect by itself. In contrast, both cell types produced IL-6 in response to TNFα, IFNγ or IL-4. and IFNγ and IL-4 exhibited synergy with TNFα. For all cytokines the levels of IL-6 production were greater for OK than SK and OK, but not SK, produced IL-6 in response to IL-1α stimulation. In addition, the IL-6 response to IL-4 stimulation was more rapid for OK than SK. These observations may explain the similarities and differences in wound healing and immuno-inflammatory diseases affecting the skin and oral mucosa.