骨髓增生异常综合征患者CD34+细胞凋亡特征

目的　调查骨髓增生异常综合征 (MDS)造血细胞CD34 抗原表达及CD34 阳性细胞凋亡状况。方法　用免疫酶标记 (碱性磷酸酶 抗碱性磷酸酶系统 ,APAAP)检测 36例MDS患者骨髓冷包埋切片中CD34 阳性细胞数量及分布特征 ,结合DNA原位末端标记技术 (ISEL)研究此类细胞的凋亡状况。14例缺铁性贫血 (IDA)患者作对照。结果　①MDS组CD34 阳性细胞较对照组明显增多 分别为 (4 9.2± 38.5 ) mm2 和 (10 .2± 9.7) mm2 ,P <0 .0 1]。MDS组凋亡细胞数与对照组比较也增多 分别为 (6 9.1±2 8.2 ) mm2 和 (17.8± 11.2 ) mm2 ,P <0 .0 1]。②CD34+ 细胞在MDS RAEB组最高 ,与MDS RA RAS和MDS RAEB t组比较 ,差异有显著性 (P值均 <0 .0 5 ) ,而在后两组间无明显差异 ;MDS RA RAS、RAEB组的细胞凋亡数均明显高于RAEB t组 (P值分别 <0 .0 2和 0 .0 5 )。③ 36例MDS患者中未见CD34 阳性细胞发生凋亡。④CD34 阳性细胞及凋亡细胞均多见于骨小梁间区 ,均有成簇成片状分布的趋势 ,但两类细胞很少分布于同一区域。结论　MDS造血细胞过度表达CD34 抗原 ,MDS转化过程中同时存在CD34阳性细胞和凋亡细胞增加。CD34 阳性细胞的凋亡抵抗现象提示其来自恶性造血克隆。

Apoptotic characteristics of CD34 positive cells in myelodysplastic syndromes

OBJECTIVE: To investigate the apoptotic situation of CD(34) positive cells in myelodysplastic syndromes (MDS). METHOD: In 36 MDS patients, immunocytochemical technique was used for the detection of the expression of CD(34) antigen and DNA in situ end labelling (ISEL) (fluorescein) for the apoptotic signals. Fourteen cases of iron deficiency anemias (IDA) were used as controls. RESULTS: (1) CD(34) expression in MDS group was much higher than that in controls (49.2 +/- 38.5 vs 10.2 +/- 9.7, P < 0.01), and MDS cases had an obviously higher apoptotic rate than control did (69.1 +/- 28.2 vs 17.8 +/- 11.2, P < 0.01). (2) Expression of CD(34) was higher in transforming group (P < 0.05) than in non-transforming and post-transforming groups. Apoptotic rates in both non-transforming/transforming group were higher than in post-transforming group (P < 0.02 and < 0.05 respectively). (3) No apoptosis was found in CD(34) positive cells in MDS; (4) Both CD(34) positive cells and apoptotic cells formed into small or large clusters but did not co-distributed in a given area. CONCLUSION: There is overexpression of CD(34) antigen on hematopoietic cells in MDS. High CD(34) expression accompanied high apoptosis coexisted in the process of transformation from MDS to AML. Apoptosis-resistance of these CD(34) positive cells suggested that they came from malignant hematopoietic cell clones.