Response of normal human keratinocytes to sulfur mustard: cytokine release†‡

Cytokines play a major role in both acute and chronic inflammatory processes, including those produced by sulfur mustard (2,2′-dichlorodiethyl sulfide, HD). This study describes responses of normal human epidermal keratinocytes (NHEK) to HD, defined by interleukin-1β (IL-1β), IL-6, IL-8 and tumor necrosis factor alpha (TNF-α) release. Commercially available enzyme-linked immunosorbent assay (ELISA) kits were used to measure the cytokine release in NHEK during exposure to 100 and 300 μM of HD. Exposure to 100 μM HD increased the release of cytokines. The amounts of IL-8 and TNF-α present in cell suspensions increased up to 59-fold and 4-fold, respectively, above control levels when NHEK were exposed to 300 μM HD. Exposure of NHEK to 300 μM HD had a highly variable effect on the release of IL-1β, where sometimes the secretion of IL-1β increased above baseline level and at other times it decreased in cell suspensions. Supernatants were collected from cell culture flasks 24 h after exposure of 100 and 300 μM HD and significantly increased levels of IL-6 were observed. Interleukin-6 was released in a concentration-dependent manner, 3.6-fold up to 8.4-fold, respectively, in supernatant. These pro-inflammatory mediators IL-1 β, IL-8, TNF-α and IL-6 may play an important role in HD injury. The present findings suggest that the cytokine changes detected could be used as potential biomarkers of cutaneous vesicant injury. Published in 2000 by John Wiley & Sons, Ltd.