BCR/ABL融合基因及细胞免疫表型检测在慢性粒细胞白血病病期演变中的意义

Significance of detection of BCR/ABL gene and celluar immuno-phenotype in development of CML

关键词:  BCR/ABL  慢性粒细胞白血病  CD33  CD34  CD117  HLA-DR

Key words:  fusion gene  bcr/abl  chronic myeloid leukemia (CML)  CD33  CD34  CD117  HLA-DR

摘要:

［目的］通过检测BCR/ABL融合基因及表面抗原在31例CML患者外周血单个核细胞中的表达，以寻找其与CML病程进展的相关性。［方法］收集31例CML患者外周血：①逆转录聚合酶链反应：检测BCR/ABL融合基因；②应用流式细胞仪检测外周血单个核细胞CD33、CD34、CD117及HLA-DR的表达。［结果］①CML患者31例，BCR/ABL融合基因检出总阳性率为83.9%；其转录本有两种：b3a2(165 bp)和b2a2(90 bp)。BCR/ABL融合基因的检出率在慢性期、加速期与急变期患者间差异无显著性意义，但缓解期检出阳性率与其他各期比较明显降低（P<0.05）。②CD33阳性检出率在各期之间比较无统计学意义（P>0.05）；CD34、CD117及HLA-DR阳性检出率在加速期及急变期明显高于慢性期（P<0.05）。［结论］①CML患者外周血单个核细胞BCR/ABL融合基因转录本有两种，即b3a2(165 bp)和b2a2(90 bp)。②b2a2转录本单独出现及b3a2和b2a2两种转录本同时出现的病例多发生在加速期和急变期，提示出现b2a2型转录本或两种转录本同时存在可能成为CML患者预后较差的标志。③CD34、CD117及HLA-DR的过度表达可提示CML患者病情不稳定及可能出现恶化。

Abstract:

［Objective］According to detect the expression of BCR/ABL fused gene and immuno-phenotypes in 31 CML patients, we expect to find the relationship between these two indexes and different phases of CML.［Methods］①Use reserve transcription nested polymerase chain reaction (RT-nested-PCR) method to detect BCR/ABL mRNA. ② Fluorescence flow cytometry was used to measure the expressions of CD33,CD34,CD117 and HLA-DR on the surface of mononuclear cells (MNC) in peripheral blood in 31 CML patients.［Results］①In 31 cases of CML, the positive expression of bcr/abl gene accounted for 83.9%. Two types of bcr/abl fused gene were found in 31 patients: b3a2(165 bp) and b2a2(60 bp). ②Out of 18 CP, 17 showed positive expression and all were b3a2 type. Out of 4 CR, 1 showed positive expression and was b3a2 type. Out of 5 AP, 4 showed positive expression and among which 2 cases were b3a2 type ,1 case was b2a2,1 case was both b3a2 and b2a2 types. Out of 4 BP, all showed positive expression and 3 cases were b3a2, 1 case was b2a2. ③The expression rates of CD33 and CD34 in 31 cases were 77.8% and 16.7% in CP,75% and 0% in CR,60% and 80% in AP, 75%and 100% in BP. CD34 was significantly higher in AP and BP than CP (P<0.05). The expression rates of CD117 and HLA-DR in 31 cases were both 0% in CP and CR, both 100% in AP and BP. Both CD117 and HLA-DR expression rates were significantly higher in AP and BP than CP (P<0.05).［Conclusions］①Two kinds of bcr/abl fused gene types as b3a2 and b2a2 were found in 26 out of 31. ②The cases showing both b3a2 and b2a2 types or single b2a2 type have a bad prognosis. ③The high expression of CD34, CD117 and HLA-DR can predict the bad prognosis of CML.