急性淋巴细胞白血病免疫分型的特点及其临床意义

目的为了探讨急性淋巴细胞白血病(ALL)各亚型免疫分型的特点及其临床意义。方法采用CD45/SSC双参数散点图设门,应用三色流式细胞术,对81例ALL的初诊患者骨髓标本进行免疫分型,并对其中45例进行核型分析。结果(1)B-ALL中CD19表达最常见(阳性率为100%),而T-ALL中CD5和CD7表达阳性率最高,均为90%;B-ALL和T-ALL都存在抗原交叉表达的现象;两组患者的完全缓解率(CR率)并无显著差异(P>0.05)。(2)伴髓系抗原表达的急性淋巴细胞白血病(My ALL)比较常见,本组达到39.5%,常累及B淋巴系统(占My ALL的84.4%);各髓系抗原中以CD13表达阳性率最高;此类患者的CR率较高,儿童CR率为72.2%,成人为78.6%。(3)急性杂合性白血病(HAL)的发病率为19.8%,以髓系、B系共同表达者居多;并且CD34表达阳性率较高(81.3%),该类患者CR率较低(儿童和成人分别为50%和40%)。(4)CD34在B-ALL,My ALL和HAL中表达阳性率较高,而T-ALL中少见(P<0.025)。结论免疫分型在诊断特殊类型的ALL(如HAL,My ALL)中具有显著优势;CD19和CD5诊断B-ALL和T-ALL的灵敏度较好,但特异性不高,存在抗原交叉表达;CD34和髓系抗原的表达与CR率无相关性,但在HAL,CD34的表达与CR率成负相关。

The Characteristics of Immunophenotype in Acute LymphoblasticLeukemia and Its Clinical Significance

Objective: To study the characteristics of immunophenotype in acute lymphoblastic leukemia (ALL) and its clinical significance. Methods: Immunophenotyping was performed on 81 ALL patients by three-color flow cytometry analysis using CD45/SSC gating, meanwhile the cytogenetic analysis was performed on 45 cases out of 81 ALL patients. Results: (1) CD 19 was the most commonly expressed of all B-lineage antigens detected with the positive rate being 100%. In T-ALL, the positive expression rate of CD5 and CD7 was the highest, being 90%. Both B-ALL and T-ALL overlapped in expression of lineage antigens. There was no significant difference in the complete remission rate (CR rate) between T-ALL and B-ALL. (2) The incidence of ALL with myeloid antigens expression (My ALL) was 39.5%. CD13 was most often seen among the myeloid markers. My ALL always involved in B-lineage antigens and the CR rate in children and adults was 72.2% and 78.6% respectively. (3) The incidence of HAL was 19.8%. Coexpression of B-lineage and myeloid-associated antigens was the commonest subtype in HAL. The expression of CD34 was commonly seen in HAL patients (81.3%). The CR rate was low in HAL, 50% for children and 40% for adults. (4) Compared to T-ALL, B-ALL, My ALL, and HAL had a higher positive rate of CD34 expression with the difference being significant (P<0.025). Conclusion: Immunophenotyping had remarkable predominance in diagnosing special category of ALL (such as HAL and My ALL); CD19 and CD5 were highly sensitive in diagnosing B-ALL and T-ALL, but less special, and overlapping was found in expression. No significant association was found between the expression of CD34 or myeloid antigens and CR rate, while low CR rate was found in HAL patients, especially for those coexpressing CD34 antigen.