Cytokine expression of human oral keratinocytes

The present study aimed to examine the cytokine expression pattern of human oral mucosa-derived keratinocytes at the protein and RNA level. The mRNA expression was measured by a RT-PCR method and the protein production was determined by an ELISA technique. In freshly isolated oral keratinocytes, IL-1alpha (interleukin 1alpha), IL-6, IL-8, transforming growth factor beta, tumor necrosis factor alpha and basic fibroblast growth factor were detectable at the protein and mRNA level, whereas platelet-derived growth factor, acidic fibroblast growth factor and transforming growth factor alpha were found only at the mRNA level. There were no detectable signals of IL-2 and IL-4. The cytokine production at the protein level was independent of prior stimulation with phorbol myristate acetate. Our results show that human oral keratinocytes - under nonpathological conditions - produce a cytokine pattern quite similar to that of epidermal keratinocytes, which may have implications for further functional studies.