221例急性早幼粒细胞白血病免疫表型特点与微小残留病检测及基因标志的关系

本研究探讨急性早幼粒细胞白血病（APL）患者的免疫表型特点与微小残留病（MRD）检测及基因标志之间的关系。采用四色流式细胞术（FCM）分析了221例初诊APL患者的免疫表型，其中87例加做CD123抗体，196例同时运用PCR检测特异融合基因pml-rarer。结果发现：初诊APL患者中CD123、CD33和CD9的阳性表达率分别为100％、99．1％和96．0％，阳性患者中平均阳性细胞比例均在90％左右；虽然CD117、CD13、CD38及CD64的阳性表达率均高于96％，但阳性患者中阳性细胞比例分布不一致，平均阳性细胞比例在70％左右；部分患者表达CD15、CD56和CD11b，多数患者不表达CD34和HLA-DR，阳性患者中阳性细胞的平均比例均较低。196例初诊APL患者中，pml—rara基因的不同转录本bcr1、bcr2和bcr3所占比例分别为63．3％、4．6％和32．1％。bcr3型基因与CD34的阳性表达相关，以20％为界时bcr3和bcr1型中CD34^＋患者的比例分别为15．4％（10／65）和3．3％（4／121）（P〈0．05）；以10％为阳性界限，bcr3和bcr1型中CD34^＋患者的比例分别为47．7％（31／65）和5．8％（7／121）（P〈0．001）；其余抗原的表达无明显区别。APL细胞中CD34为阳性且表现为非高侧向角（NL-SSC）时高度提示基因为bcr3型。结论：APL患者的免疫表型具有独特特征，CD123、CD33和CD9更适用于APL的MRD检测，CD34的阳性表达、NL-SSC与bcr3基因亚型相关，CD34的阳性界限设为10％更能提示基因类型与抗原表达的关系。

Relationship of Immunophenotypic Features with Minimal Residual Disease Detection and Gene Types in 221 Cases of Acute Promyelocytic Leukemia

This study was aimed to investigate the relationship of immunophenotypic features with minimal residual disease （MRD） detection and gene types in APL patients. Inmmunophenotypes were analyzed in 221 newly diagnosed APL patients by using four-color flow cytometry. Among of them, CD123 antibody was examined in 87 patients and the fused gene pml-rarα were detected by PCR in 196 specimens simultaneously. The results of immunophenotyping demon- strated that the positive percentages of CD123, CD33 and CED in newly diagnosed APL patients were 100%, 99.1% and 96.0% respectively, and mean percentages of positive cells in positive patients were all around 90%. Although the positive rates of CD117, CD13, CD38 and CD64 were all above 96%, but the mean percentages of positive cells in different positive patients were diverse and average percentages of positive cells were about 70%. CD15, CD56 and CD1 lb were expressed in some patients, but CD34 and HLA-DR were rarely expressed in the majority of patients, and average positive percentages were all lower. Among 196 newly diagnosed APL patients, bcrl, bcr2 and bcr3 expressions were 63.3%, 4.6% and 32.1% respectively. The results showed a strong correlation of positive expression of CD34 with bcr3 isoform. When cut-off value was chosen as 20%, the proportions of CD34 positive patients in bcr3 and bcrl cases were 15.4 % （10/65 ） and 3.3 % （4/121 ） separately, which had a significant difference （p 〈 0.05 ）. When cut-off value was 10% , bcr3 cases had a significantly higher percentage of CD34 positive, compared with bcrl cases （p 〈0. 001 ）, which was 47.7 % （ 31/65 ） and 5.8 % （ 7/121 ） respectively. However, there was no statistically significant difference on the other antigens between the two groups. Bcr3 isoform was highly indicated when CD34 was positive and non large side scatter（NL-SSC） was shown in APL cells. It is concluded that there is a unique characteristics of immunophenotyping, and antigens such as CD123, CD33 and CD9 are more applicable to the detection of MRD in APL patients. The positive expression of CD34 and NL-SSC are associated with bcr3 isoform, and the relationship between gene type and antigen expression can be suggested more accurately when the cut-off value is chosen as 10%.