The importance of protease histochemistry in pathology.

The histochemical demonstration of the activities of proteases, based in the majority of cases on the use of discriminating synthetic substrates (aminoacyl or peptidyl derivatives of 4-methoxy-2-naphthylamine [MNA]), has proved very valuable in pathology. Its importance is illustrated by three topics investigated in our laboratory, namely lymphocytes, malabsorption syndrome and atherosclerosis.