Elevation of Cytosolic Aminopeptidase in Patients with Viral Infection

Abstract

Cytosolic aminopeptidase (c-AP: EC 3. 4. 11. 1) is contained in the cytosolic fraction of hepatic cells, lymphocytes, leukemia and lymphoma cells, and other kinds of cells. Elevations of the level of this enzyme in sera have been observed in patients with hepatic diseases or lymphoproliferative disorders. Moreover, increases in c-AP activity have been observed in patients with several viral infections. In this study, the c-AP activity of patients with viral infections was found gradually to begin to increase during the prodromal phase along with increase in lactate dehydrogenase (LD: EC 1. 1. 1. 27) activity, rapidly increased with the appearance of rash, and returned to the normal reference interval more quickly than did LD. Since there were no associated increases in liver-derived enzymes, this increase in c-AP probably originated from lymphocytes and not hepatic cells. We conclude that the measurement of c-AP activity of importance for the diagnosis and follow-up of patients with certain viral infections.