Multiphoton microscopy: an optical approach to understanding and resolving sulfur mustard lesions

Sulfur mustard (SM; 2,2(')-dichloroethyl sulfide) is a percutaneous alkylating agent first used as a chemical weapon at Ypres, Belgium, in World War I. Despite its well-documented history, the primary lesions effecting dermal-epidermal separation and latent onset of incapacitating blisters remain poorly understood. By immunofluorescent imaging of human epidermal keratinocytes (HEK) and epidermal tissues exposed to SM (400 microM for 5 min), we have amassed unequivocal evidence that SM disrupts adhesion complex molecules, which are also disrupted by epidermolysis bullosa-type blistering diseases of the skin. Images of keratin 14 (K14) in control cells showed tentlike filament networks linking the HEK's basolateral anchoring sites to the dorsal surface of its nuclei. Images from 6-h postexposure profiles revealed early disruption (