Arginine esterase in cystic fibrosis of the pancreas.

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 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. 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. 