Immunologic cytokine expression in human keratinocytes after exposure to sulfur mustard

Human keratinocytes (HK) participate in immunologic events influencing the behavior of resident cells and inflammatory cells in skin. It is clear that cytokines, immunologically active protein molecules that bind to specific receptors on target cells, are produced by keratinocytes. Specifically, keratinocytes have recently been recognized to exhibit the capacity to release interleukin (IL) 1β, IL-6, IL-8, and tumor necrosis factor-α (TNF-α), which influence the growth, function, and differentiation of dermal and epidermal cells. Since HK have been demonstrated to be a potent source of various ILs, we investigated the effect of bis-(2-chloroethyl)sulfide [sulfur mustard, HD] in saline upon the expression of these cytokines. Using enzyme-linked immunosorbent assay kits, we found that after a 3-h exposure to 1 mM HD, adult and neonatal normal HK cell cultures show a significant decrease in the expression of all cytokines listed previously, with the exception of TNF-α in adult HK, which is only slightly decreased. These results indicate that IL-1β, IL-6, and IL-8 levels in HK cell cultures 3 h after HD exposure may provide a means for measuring the immunologic response.