Studies on immunoreactive pancreatic elastase 2 in human serum.

A radioimmunoassay for human pancreatic elastase 2 is described. DFP-Inactivated pancreatic elastase 2 is used both as standard and tracer. The concentration in normal human plasma is approximately 60 micrograms immunoreactive pancreatic elastase 2, which rises in acute pancreatitis. Pancreatic elastase 2 appears in plasma in a form with a molecular size exceeding that of the proenzyme. In vitro studies demonstrate that a complex between pancreatic elastase 2 and alpha 1-antitrypsin arises after incubation of a mixture of pancreatic juice and plasma. The results presented support the conclusion that proelastase is bound by alpha 1-antitrypsin after the discharge from the pancreatic gland to the extracellular tissue fluids around the gland.