Proteolytic activity of blowfly larvae secretions in experimental burns.

Secretions of larvae of the blowfly Calliphora erythrocephala digested experimental rat skin burn eschar in vivo and in vitro when applied topically in a vanishing cream base. Debridement was characterized by de-epithelialization and digestion of dermal collagen to a subfollicular level over a 3-day period. Analytic investigation of the secretions demonstrated the presence of enzymes with activities characteristic of trypsin, leucine aminopeptidase, and carboxypeptidases A and B. These were partially characterized. There was no evidence of chymotrypsin, elastase, or collagenase. Preparation of a suitable therapeutic form could result in a preparation useful for enzymatic debridement.