Morphologic Effects of Sulfur Mustard on a Human Skin Equivalent

Abstract Testskin, a commercially available human skin equivalent, was used as a model system to study the temporal morphologic effects of a single vesicating vapor dose of sulfur mustard (HD). Samples were exposed to 10 μl HD vapor for 8 min and harvested at 1, 3,6, 12, and 24 hr following exposure. Control samples not exposed to HD were harvested at 0 and 24 hr. Light and electron microscopic analysis revealed that the basal cell of the stratum germinativum was selectively affected beginning at 3-6 hr. These early basal cell changes included an apparent widening of intercellular spaces, a disabling of desmosomal attachments, rounding of cells, nuclear condensations and pyknosis, rearrangement of cytoplasmic tonofilaments to a perinuclear position, and perinuclear blebbing. At 12 and 24 hr, the cyto-pathologic changes progressed to cytoplasmic vacuolation, swollen endoplasmic reticulum, electron opacities, and necrosis, which now involved suprabasal cell layers as well. At the basement membrane zone, cellular debris and cellular fragments accumulated in the area of the lamina lucida, which appeared to widen this space resulting in the formation of a cleft. In the course of this morphologic study it was observed that skin structures normally present in vivo were absent or incomplete in the human skin equivalent specimens. These included hemidesmosomes, a basement membrane, anchoring filaments, and anchoring fibrils.