Proteolytic enzymes in blister fluids from patients with dermatitis herpetiformis.

Proteolytic enzymes may be involved in blister formation in dermatitis herpetiformis (DH). We have examined collagenase, gelatinase and elastase-like enzyme activities in fluids collected from spontaneous blisters and from suction blisters raised on developing DH-lesions induced by application of potassium iodide. Control suction blisters were raised on unaffected DH-skin and on healthy volunteers. High enzyme activities were found in spontaneous blisters, and suction blister fluids obtained from developing lesions showed increased levels of gelatinase and elastase-like enzymes. Inhibitor studies revealed that a part of the elastase-like enzyme activity might be derived from inflammatory cells. Gel filtration chromatography disclosed two separate elastase-like enzymes which, as they had high molecular weights, could be either enzyme-inhibitor complexes or aggregates.