Development of a radioimmunoassay for pig pancreatic kallikrein.

A radioimmunoassay for the determination of pig pancreatic kallikrein was developed. The chloramine-T method was employed for the labelling of the antigen with 125I. The assay allows the determination of kallikrein in concentrations as low as 0.4 microgram/l. Pig urinary and pig submandibular kallikreins are indistinguishable from pig pancreatic kallikrein by the assay. No cross reactivity was observed for bovine trypsin and chymotrypsin, porcine trypsin and kallikreins of guinea pig submandibular glands and guinea pig coagulation glands. Because of the high specificity of the assay, which is not attainable with conventional assays based on the enzymatic activity, the radioimmunoassay is highly suited for investigations into the physiological role and the pharmacological mechanism of action of pig glandular kallikreins.