Effects of CEES on inflammatory mediators, heat shock protein 70A, histology and ultrastructure in two skin models

Chemical warfare threats require the development of diverse models for the assessment of countermeasures. Human skin products, Skin(2)(R) (differentia ting keratinocytes on a fibroblast-collagen matrix) and EpiDerm(R) (differe ntiating keratinocytes) were exposed (2 h) to the sulfur mustard 2-chloroet hyl ethyl sulfide (CEES, 1-2 mg 1(-1) min(-1)) in humidified air or to humi dified air alone. Tissues were evaluated histologically, ultrastructurally and for viability 22 h later; media and tissues were also analyzed for infl ammatory mediators. Histology showed that GEES induced the separation of de rmal and epidermal regions in Skin(2) with severe damage to basal keratinoc ytes, Histology and electron microscopy of both products revealed condensat ion of nuclear chromatin, retraction of spinous processes, collapse of the tonofibrillar network and cytoplasmic vacuolization and blebbing in those c ells with loss of pseudobasement membrane integrity. Exposure of Skin(2) to CEES increased extracellular interleukin-1 alpha (IL-1 alpha), prostagland in-E-2 (PGE(2)) and especially IL-1 receptor antagonist (IL-1Ra) release (5 6334 vs 84 614 pg ml(-1)), but decreased interleukin-6 (IL-6, 4755 vs 351 p g ml(-1)). Exposure of EpiDerm to CEES led to unaffected extracellular and reduced intracellular IL-1 alpha (371 vs 92 pg ml(-1)). Extracellular IL-1R a greatly increased (2375 vs 24875 pg ml(-1)), whereas cellular levels decr eased (165425 vs 96625 pg ml(-1)). Extracellular (224 vs 68 pg ml(-1)) and intracellular (485 vs 233 pg ml(-1)) soluble interleukin-1 receptor II (sIL -1RII) decreased. Prostanglandin E-2 increased (1835 vs 2582 pg ml(-1)), wh ereas heat shock protein 70A (Hsp70A) remained statistically unchanged (570 00 vs 96000 pg ml(-1)). Failure to obtain a heat shock response to CEES may contribute to the susceptibility of tissue to the alkylating agent. Consis tent and marked responses of cellular and extracellular IL-1Ra to GEES sugg est a potential for use as a tissue status marker and primary antiinflammat ory regulator in skin.