Evidence for an immune response to HLA class I antigens in the vanishing-bileduct syndrome after liver transplantation.

The relation between donor and recipient status for HLA class I and II antigens in 62 patients undergoing liver transplantation was examined with particular reference to a well-defined variant of chronic rejection, the vanishing-bileduct (VBD) syndrome. A complete mismatch for class I antigens was more common in those with the VBD syndrome than in those with normal graft function or chronic graft malfunction unrelated to the syndrome (p less than 0.025). In contrast, a complete mismatch for class II antigens was considerably less common in those with the VBD syndrome than in those without (p less than 0.02). The association of a complete mismatch for class I and a partial or complete match for class II antigens with the VBD syndrome was highly significant (p less than 0.0005). These findings support the hypothesis that in the VBD syndrome both class I antigen expression on bileduct epithelium and immunological interaction at the level of class II antigens are required for the rejection process to occur. In addition, high-titre donor-specific antibodies to class I antigen, which were present in 6 of 14 of those with the VBD syndrome but in none of those without (p less than 0.0005), may be involved in the pathogenesis of bileduct damage.