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

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.