Effect of cytokines on IL-15 receptor expression in human oral keratinocytes cell line

ABSTRACT

Interleukin-15 [IL-15] is a cytokine produced by mononuclear phagocytes and probably many other cell types in response to viral infections, lipopoly-saccharides [LPS], and other signals that trigger innate immunity. IL -15 mRNA is expressed in non-lymphoid tissues such as heart, lungs, liver, kidneys, placenta, skeletal muscle and also in keratinocytes and dendritic cells in skin. The actions of IL-15 are mediated via its receptor [IL-15R]. IL-15 is known to be expressed in a variety of tissues, including epithelial cells, beta-1 cells, and natural killer cells. It is not known whether these are present in the oral buccal mucosa. The present study was carried out at The department of Oral Pathology, Queen Mary College of Medicine and Dentistry, Barts and The London, UK, to determine whether a human oral buccal mucosal [keratino-cytes] cell line, TR 146, expressed IL-15 receptor and whether the expression of IL-15R is varied when TR146 cells were exposed to different cytokines such as IL-15, IL-8, IL-1beta, or TNF-alpha Immunocytochemistry analysis revealed that TR146 cells expressed IL-15R when incubated with IL-15 and IL-8 and a modest increase was seen with IL-1beta /TNF-alpha. RT-PCR indicated that the TR-146 cells constitutively expressed IL-15R which did not appear to be up-regulated upon exposure to the cytokines use