title: Molecular forms of immunoreactive pancreatic cationic trypsin in pancreatitis patient sera.
abstract: The molecular forms of immunoreactive pancreatic cationic trypsin in sera of patients with acute pancreatic inflammation have been characterized using a radioimmunoassay technique that is capable of detecting trypsinogen as well as trypsin bound to alpha 1-antitrypsin. Trypsin bound to alpha 2-macroglobulin is not immunoreactive under normal assay conditions. However, alpha 2-macroglobulin-bound trypsin can be detected after gel filtration of serum on Bio-Gel A-0.5 m and acid treatment of column fractions. The average serum level of immunoreactive cationic trypsin from 20 patients with acute pancreatic inflammation was 1,590 ng/ml. An average normal value of 26 ng/ml has been obtained previously. Serum samples from 14 patients with pancreatic inflammation were chromatographed under conditions that resolve trypsinogen, alpha 1-antitrypsin-bound trypsin, and alpha 2-macroglobulin-bound trypsin. In each case, the major portion of the immunoreactive material eluted at a position corresponding to free trypsinogen, while a minor fraction of the immunoreactive material appeared to be trypsin bound to alpha 1-antitrypsin. The zymogen nature of the major peak was confirmed in one case by activation with human enteropeptidase. In 11 of 14 patients, acid treatment of the alpha 2-macroglobulin peak yielded immunoreactive trypsin.
mesh_terms: D002412:Cations; D004765:Enteropeptidase / Q000494:pharmacology; D004789:Enzyme Activation; D006801:Humans; D008970:Molecular Weight; D010195:Pancreatitis / Q000097:blood*; D011863:Radioimmunoassay; D014357:Trypsin / Q000097:blood*; D014362:Trypsinogen / Q000097:blood*; D000515:alpha 1-Antitrypsin / Q000378:metabolism; D000511:alpha-Macroglobulins / Q000378:metabolism
chemical_list: D002412:Cations; D000515:alpha 1-Antitrypsin; D000511:alpha-Macroglobulins; D014362:Trypsinogen; D014357:Trypsin; D004765:Enteropeptidase