HLA class II alleles in Japanese patients with immune thrombocytopenic purpura. Associations with anti-platelet glycoprotein autoantibodies and responses to splenectomy.
HLA class II alleles and immunoglobulin allotypes were determined in 83 Japanese patients with immune thrombocytopenic purpura (ITP) and 114 race-matched healthy controls. Distribution of DRB and DQB1 alleles as well as G1M(f, z), G2M(n+, n-), and KM(1, (1,2), 3) were not different between ITP patients and healthy controls, while DPB1*0201 was marginally increased in ITP patients vs. healthy controls (51% vs. 28%, Pc= 0.04, OR=2.6 [1.4-4.8]). In contrast, strong associations between anti-glycoprotein autoantibodies and HLA class II genes were found as follows: antiGPIIb-IIIa antibody with DRB1*0405 and DQB1*0401; and anti-GPIb-IX antibody with DRB1*0803 and DQB1*0601. When factors influencing therapeutic responses to splenectomy were examined, a poor response was correlated with the presence of DRB1*0405, DQB1*0401 and anti-GPIIb-IIIa antibody (P=0.01, 0.002, and 0.03, respectively). Our results indicate that HLA class II genes influence the production of anti-glycoprotein antibody specificities rather than the development of ITP. In addition, HLA class II genotyping could be useful in predicting therapeutic responses to splenectomy in Japanese patients with ITP.
Kuwana
M
M
Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan. kuwanam@med.keio.ac.jp
Kaburaki
J
J
Pandey
J P
JP
Murata
M
M
Kawakami
Y
Y
Inoko
H
H
Ikeda
Y
Y
D000328:Adult; D000483:Alleles; D001323:Autoantibodies / Q000276:immunology; D005260:Female; D000949:Histocompatibility Antigens Class II / Q000235:genetics* / Q000276:immunology; D006801:Humans; D008297:Male; D010980:Platelet Membrane Glycoproteins / Q000276:immunology; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000235:genetics* / Q000276:immunology / Q000601:surgery; D013156:Splenectomy
D001323:Autoantibodies; D000949:Histocompatibility Antigens Class II; D010980:Platelet Membrane Glycoproteins