ASSOCIATION OF PRIMARY BILIARY-CIRRHOSIS WITH HUMAN-LEUKOCYTE ANTIGEN-DPB1-ASTERISK-0501 IN JAPANESE PATIENTS

To investigate the relationship between distribution of human leukocyt e antigen alleles and susceptibility to primary biliary cirrhosis amon g Japanese, we performed serological typing and human leukocyte antige n DP genotyping in 47 Japanese patients with primary biliary cirrhosis . Serologically, the frequency of human leukocyte antigen DQ3 was sign ificantly higher in the patients than in healthy controls, whereas fre quency of DR52 was significantly lower in the patients. Human leukocyt e antigen DP genotyping using the polymerase chain reaction-restrictio n-fragment-length polymorphism method showed that the frequency of hum an leukocyte antigen DPB10501 (85.1%) was significantly higher in pat ients than in healthy controls but that the frequency of DPB10402 was significantly lower in patients. The positive association of human le ukocyte antigen DPB10501 with primary biliary cirrhosis was stronger than that of serological human leukocyte antigen DQ3, which can be exp lained by its linkage to DPB10501. In addition, three of seven DPB1*0 501-negative patients had DPB10202, suggesting that the human leukocy te antigen DPB1 amino-acid chain plays an important role in the immuno genesis of primary biliary cirrhosis among Japanese patients. Comparat ive analysis of amino acid sequences from DPB1 alleles indicated that a Leu at position 35 of the DPB1 chain likely contributes to the susce ptibility to primary biliary cirrhosis among the Japanese.