Arginine esterase in cystic fibrosis of the pancreas.

Abstract

Extract: Arginine esterase activity in chloroform-ellagic acid-treated plasma from 11 patients with cystic fibrosis (CF) and 12 age-matched control subjects has been resolved into its component fractions by ion exchange chromatography on DEAE-Sephadex and electrofocusing on polyacrylamide gels. The activity can be resolved into two fractions by chromatography, one of which is inhibited by soybean trypsin inhibitor (STI) and the other of which is not inhibited by STI. In plasma of CF patients, the fraction of activity inhibited by STI is reduced to approximately 30% of the corresponding fraction in control plasma. In contrast, the fraction of activity resistant to inhibition by STI did not show any significant quantitative differences between control and CF plasma samples. Analysis of the plasma samples by electrofocusing on 5% polyacrylamide gels in the range of pH 5.0–8.0 and subsequent staining for arginine esterase activity showed qualitative differences between control and CF plasma samples. Six activity bands could be detected in control samples, whereas five bands were detected in CF samples. Eight samples had one type of band missing, two had another type of band missing, and one had yet another type of band missing. All of these bands were restricted to a narrow pH zone in the center of the gel. These data are consistent with and extend our earlier reports of differences in arginine esterase activity between plasma samples of CF patients and control subjects. The demonstration of the absence of a single band of arginine esterase activity is consistent with the absence of a specific arginine esterase isoenzyme in patients with CF. Speculation: The deficiency of arginine esterase in patients with cystic fibrosis may account for the presence of “factors” in saliva, plasma, and fibroblasts of these patients and consequently for the clinical manifestations of the disease.