【摘要】 目的　研究人类白细胞抗原 (human leukocyte antigen,HL A) DRB1等位基因与儿童特发性血小板减少性紫癜 (idiopathic thrombocytopenic purpura,ITP)的关系。方法　用聚合酶链反应 -序列特异的寡核苷酸探针杂交技术对 4 2例 ITP患儿进行了 HL A- DRB1等位基因分型 ,同时用改良的血小板抗原单抗特异性固相化法检测了其中 36例 ITP患儿血清中的抗 GP b/ a和抗 GPIb/ x自身抗体。结果　与健康对照相比 ,ITP患儿 HL A- DRB1* 17基因频率显著升高 (P<0 .0 5 ,RR=2 .76 ,EF=0 .10 6 4 ) ,而HL A- DRB1* 12 0 2基因频率显著降低 (P<0 .0 2 5 ,RR=0 .2 0 ,PF=0 .76 16 ) ;慢性难治性 ITP患儿与非难治性患儿相比 ,HL A- DRB1* 11基因频率显著升高 (χ2 =6 .0 91,P<0 .0 2 5 ) ,且具有 DRB1* 11的患儿主要(5 / 6 )为女性年长患儿 ;抗 GP b/ a及抗 GPIb/ x自身抗体的阳性率都与 HL A- DRB1* 0 2 (15 / 16 )基因显著相关 (P分别为 0 .0 2和 0 .0 1) ,但难治性和非难治性 ITP患儿间抗体阳性率差异无显著性 (P>0 .1)。结论　 DRB1* 17可能与儿童 ITP的易感性有关 ,而 DRB1* 12 0 2则可能对儿童 ITP的发病具有保护作用 ;具有 DRB1* 11基因的患儿易发展为慢性难治性 ITP;血小板自身抗体与抗原表位的反应可能受DRB1*更多还原

【Abstract】 Objective To gain an insight into the relations between human leukocyte antigen DRB1 (HLA DRB1) alleles and idiopathic thrombocytopenic purpura (ITP) in children. Methods Polymerase chain reaction sequence specific oligonucleotide (PCR SSO) was used to identify DRB1 alleles of 42 children with ITP. Among them, 36 were identified for anti GPⅡb/Ⅲa and anti GPIb/Ⅰx autoantibody by modified monoclonal antibody specific immobilization of platelet antigens. Results Compared with health controls, the frequency of HLA DRB1*17 significantly increased ( P <0.05, relative risk=2.76, etiologic factor=0 1064) and the frequency of HLA DRB1*1202 significantly decreased ( P <0.025, relative risk=0.20, prophylactic factor=0.7616) in children with ITP. In comparison with patients of good response to steroids and IVIgG therapy, the frequency of HLA DRB1*11 significantly increased (χ 2=6.091, P <0.025) in patients with a poor response, furthermore, the most of HLA DRB1*11 positive patients were female teen agers. Twenty seven patients (75%) had anti GPⅡb/Ⅲa and seventeen (47.22%) had anti GPⅠb/Ⅰx autoantibodies. The positivities of both anti GPⅡb/Ⅲa ( P =0.02) and anti GPIb/Ⅰx ( P =0.01) were associated with HLA DRB1*02. However, the positivity of autoantibodies between refractory and non refractory patients showed no significant difference. Conclusion The allele of HLA DRB1*17 seems to predict susceptibility of ITP in children, while HLA DRB1*1202 appears to be protective to ITP. The allele of HLA DRB1*11 plays an important role in resistance to steroid and IgG therapy in children with ITP. It seems that the response to the antigenic epitope of GPⅡb/Ⅲa and GPⅠb/Ⅰx is restricted by HLA DRB1*02, while the presence of the antibodies could not predict prognosis. In conclusion, the above preliminary findings indicate that genetic factors influence the clinical course of ITP, but the exact mechanism needs to be investigated further.更多还原