Incidence of antibodies against rabbit liver specific lipoprotein (RLSP) in chronic active hepatitis

Abstract

In chronic active hepatitis (CAH) evidence exists that circulating autoantibodies against liver specific lipoprotein (LSP) could play a role in the development of hepatocellular injury. We evaluated the presence of autoantibodies in CAH against LSP using rabbit LSP, as antigen in a radioimmunoprecipitation test. Fifty-one patients with histologically diagnosed CAH were investigated. Among these 16 were HBsAg+, 15 were HBsAg-/anti-HBc+, 10 were non-A, non-B, 10 were autoimmune CAH. Anti-LSP were detected in six of 16 (37%) HBsAg+ (mean titre of 1:198); four of 15 (33%) HBsAg-/anti-HBc+ (mean titre of 1:246); two of 10 (20%) non-A, non-B (mean titre of 1:185); seven of 10 (70%) autoimmune CAH (mean titre of 1:307). No correlation was evident between the titre of anti-LSP and the values of AST, bilirubin or IgG. The findings seem to be consistent with the following conclusions: (a) CAH patients develop an humoral immune response to determinants in LSP which are not species specific. This is further evidence that rabbit LSP could be considered a suitable alternative to the human preparation in evaluation of autoimmunity in CAH and (b) the different behaviour of anti-LSP in patients with viral CAH (B, non-A, non-B) in respect of patients with autoimmune CAH suggests a variable importance of these antibodies in the mechanism of ongoing liver cell injury according to the various types of CAH.