Variations in the glycoforms of serum alpha 1-antichymotrypsin in liver diseases and after liver transplantation.

Abstract

1. Using crossed immunoaffinity electrophoresis with free concanavalin A in the first dimension, we studied the microheterogeneity of alpha 1-antichymotrypsin due to various glycoforms in sera from patients with various liver diseases and after liver transplantation. 2. Studies by isoelectric focusing and immunoblotting and by crossed immunoelectrophoresis without concanavalin A in the first dimension allowed us to show that there is no dramatic variation in electrophoretic heterogeneity of alpha 1-antichymotrypsin in the serum of patients with liver diseases or after liver transplantation when compared with that of normal subjects. Therefore the heterogeneity observed in crossed immunoaffinity electrophoresis is due to various interactions with concanavalin A. 3. The results were expressed as the ratio of concanavalin A non-reactive glycoforms plus concanavalin A weakly reactive glycoforms to concanavalin A reactive glycoforms, called R alpha 1-ACT. R alpha 1-ACT was significantly higher in patients with cirrhosis (n = 53) when compared with normal subjects (n = 30). The median R alpha 1-ACT was 1 (range 0.72-1.25) in normal subjects. It was 1.6 (range 1.18-3.02), 1.45 (range 0.65-4.12) and 2.24 (range 1.03-19) in cirrhosis of Child's grade A, B and C, respectively. There was a dramatic decrease in glycoforms with mostly biantennary glycans in some patients with Child's grade C cirrhosis. Serum levels of alpha 1-antichymotrypsin were lower than normal only in some patients with Child's grade C cirrhosis. 4. Among the patients with acute viral hepatitis studied (n = 17), five were studied longitudinally.(ABSTRACT TRUNCATED AT 250 WORDS)