Exocrine pancreatic proteins in serum during pancreatic allograft rejection.

The serum concentrations of immunoreactive pancreatic secretory trypsin inhibitor, cationic elastase, anionic trypsin, cationic trypsin, and total amylase activity, were studied after pancreatic allograft transplantation. Nine patients received whole organ pancreaticoduodenal allografts with exocrine drainage to the bladder. Eight of the patients received simultaneously a renal allograft. The serum concentration of immunoreactive cationic elastase increased gradually during the first postoperative days to a peak on the fifth day after surgery; all other proteins decreased in concentration after the first day. Eighteen episodes of pancreatic and/or kidney rejection, diagnosed by means of kidney biopsy, urinary cytology, kidney function, and urinary amylase levels, were analyzed. The pancreatic proteins displayed different patterns in serum concentration during the days immediately before diagnosis of rejection. The pancreatic secretory trypsin inhibitor showed the most pronounced peak in serum concentration during rejection and even reacted during some episodes without a decline in urinary amylase output. Cationic elastase on the other hand showed no reaction at all. From this homogeneous material it is possible to conclude that changes in serum concentrations during rejection are not the same for all pancreatic exocrine proteins.