Purification of human pancreatic kallikrein and organ-specificites of human glandular kallikreins

Abstract

Human pancreatic kallikrein (H. Panc. K.) was purified from human pancrea by serial liquid chromatographies. The final preparation had a specific activity of 9.2AU/A₂₈₀ (AU: amidase unit for H-Pro-Phe-Arg-MCA) and its N-terminal sequence coincided with the reported sequence determined from cloned cDNA analysis. In HPLC (gel filtration), one symmetrical peak corresponding to a molecular weight of 48, 000 was obtained. In SDS-PAGE without 2-mercaptoethanol, one band corresponding to a molecular weight of 52, 000 was obtained. Protease inhibitor specificites of H. Panc. K. were the same as those of human urinary kallikrein (HUK) and hog pancreatic kallikrein (hog Panc. K.), while anti-HUK rabbit antibody inhibited the activities of H. Panc. K. and HUK, but not that of hog Panc. K.. From the analyis of affinity for concanavalin A and erythroaggulutinating phytohemagglutinin, the carbohydrate parts of H. Panc. K. are relatively rich in bi-(or multi-) antennary complex type sugar chains with bisecting G1cNAc compared with those of human salivary kallikrein and HUK. These findings will be a help to clarify the physiological and pathophysiological roles of H. Panc. K. in the pancreas and pancreatic diseases, especially in acute pancreatitis.