Immunogenetic analysis of patients with post-schistosomal liver cirrhosis in man.

Immune responsiveness of 121 patients with post-schistosomal liver cirrhosis to schistosomal antigens was investigated. Out of 78 patients, only five (6.4%) showed low responsiveness to schistosomal adult worm antigen whereas 73 (93.6%) were high responders. Out of 57 healthy individuals with previous schistosomal infection, low responders were found in 17.5%. The frequency of low responders to schistosomal adult worm antigen was significantly decreased in the patients with post-schistosomal liver cirrhosis (P less than 0.05). Out of 121 patients, a significant increase in frequency of HLA-Bw44-DEn haplotype was observed (corrected P less than 0.02). On the other hand, HLA-Bw52-Dw12 haplotype which was reported to be in strong linkage disequilibrium with an immune suppression gene for schistosomal adult worm antigen was significantly decreased (corrected P less than 0.005). These observations suggested that an HLA-linked immune suppression gene controlled susceptibility or resistance to post-schistosomal liver cirrhosis through regulation of immune responsiveness of the hosts to schistosomal antigen in man.