Acid hydrolases in blister fluid. I. Characterization and quantification of acid phosphatase.

Acid phosphatase has been characterized and quantified in human suction blister fluid, interstitial fluid and serum. The acid phosphatases of suction blister fluid and serum showed differences in their pH activity curves, Michaelis-Menton constants, heat stabilities and sensitivities to inhibition by tartrate and fluoride. The behaviour of the interstitial fluid enzyme was intermediate between these two. The levels of activity in blister fluid and serum were very similar, both being more than twice that of interstitial fluid. These results suggest that the acid phosphatase activity in suction blister fluid is derived largely from the overlying epidermis rather than from serum.