Carcinoembryonic antigen, alpha 1-antitrypsin, and alpha-fetoprotein in the pancreas of patients with cystic fibrosis

The ductular accumulation of "abnormal mucus" is the key histologic feature in cystic fibrosis. This material is periodic acid-Schiff positive and diastase resistant, suggesting that it is glycoprotein in nature. We used the avidin-biotin-peroxidase method to identify this material using antibodies to the serum glycoproteins carcinoembryonic antigen, alpha 1-antitrypsin, and alpha-fetoprotein on paraffin sections of pancreas obtained from a total of 21 patients: 9 with cystic fibrosis, 5 with chronic pancreatitis, and 7 controls. The control patients had normal pancreatic histologic findings, no alpha 1-antitrypsin or alpha-fetoprotein was demonstrated, and only the ductular epithelium reacted weakly for carcinoembryonic antigen. The pancreas in pancreatitis showed fibrosis, acinar atrophy, and ectasia of the ducts that contained only a small amount of periodic acid-Schiff-positive material. This material reacted weakly for carcinoembryonic antigen and alpha 1-antitrypsin. The appearance of the pancreas in cystic fibrosis was similar to that in chronic pancreatitis. However, the ducts contained a greater amount of periodic acid-Schiff-positive material, mostly in the form of globules that reacted strongly for carcinoembryonic antigen and alpha 1-antitrypsin and weakly for alpha-fetoprotein, as did the ductular epithelium. This study shows that the periodic acid-Schiff-positive material in cystic fibrosis contains at least the three serum glycoproteins and that the accumulation may represent a possible defect in cellular synthesis, assembly, or transport of glycoproteins in the ducts.