再生障碍性贫血患儿HLA-DRB1*15表达及其与免疫抑制治疗疗效的关系

Expression of HLA-DRB115 Genotype in Children with Acquired Aplastic Anemia and Its Relation to Effect of Immunosuppressive Therapy

本研究探讨再生障碍性贫血(AA)患儿HLA-DR基因表达情况及其与免疫抑制治疗疗效的关系,评价HLA-DRB1*15基因型检测的临床意义。采用SSP-PCR方法对40例(特发性33例,继发性7例)获得性AA儿童和107名正常对照人群进行HLA-DR位点基因检测,其中32例AA患儿接受了免疫抑制治疗(其中强化免疫抑制治疗24例,单纯CsA治疗8例),比较AA患儿和健康人群HLA-DR基因表达差异,观察AA儿童HLA-DRB1*15表达与免疫抑制治疗疗效、疾病复发的关系。结果显示,特发性AA患儿HLA-DRB1*15(+)率为51.5%(17/33),较正常对照人群(20.6%)显著增高(p<0.01),7例继发性AA患儿均为HLA-DRB1*15(-)。HLA-DRB1*15(+)组AA患儿经免疫抑制治疗后6个月有效率和完全缓解(CR)率分别为93.8%、87.5%,而在HLA-DRB1*15(-)组分别为56.3%和31.3%,两组比较差异均具有极显著意义(p<0.01)。5例复发患儿均为HLA-DRB1*15(+)。结论:AA患儿HLA-DRB1*15基因表达频率较正常人群显著增高,HLA-DRB1*15(+)AA患儿对免疫抑制治疗反应好,疾病完全缓解率高。

This study was purposed to investigate the frequency of HLA-DRB1 ＊ 15 expression in children with aplastic anemia （AA） and its relation to effect of immunosuppressive therapy. HLA-DR genotypes were detected by SSP-PCR in 40 patients with acquired aplastic anemia and 107 normal controls, and the expressions of HLA-DR gene in AA patients and normal controls were compared. 32 out of 40 patients were treated with immunosuppressive therapy, which included antilymphocyte globulin combining with cyclosporine or cyclosporine alone, the relation of HLA-DRB1 ＊ 15 expression to efficacy of immunosuppressive therapy and relapse of AA was explored. The results showed that the mean age of the patients was 9.0 years with a ratio of male to female 1.5 ： 1. The frequency of HLA-DRB1 ＊ 15 genotype expression in patients with idiopathic aplastic anemia was 51.5% （ 17/33 ）, which was markedly higher than that of healthy controls （20.6% , p 〈0.01 ）. All of 7 patients with second acquired aplasitic anemia showed negative expression of HLA -DRB1 ＊ 15. The rates of all responses, including complete remission and partial remission （ CR ＋ PR）, and CR to immunosuppressive therapy in 16 patients who beared HLA-DRB1 ＊ 15 were 93. 8% and 87. 5% respectively, which were higher significantly than those of patients without bearing HLA-DRB1 ＊ 15 （56. 3% and 31.3%, p 〈 0.01 ）. Relapse occurred in 5 patients who beared HLA-DRB1 ＊ 15 genotype. It is concluded that the frequency of HLA-DRB1 ＊ 15 genotype expression in children with AA is significantly higher than that in normal controls, and the immunosuppressive therapy for patients beared HLA-DRB1 ＊ 15 shows favourable effect with high incidence of complete remission.