骨髓增生异常综合征骨髓单个核细胞c-kit受体表达及功能的研究

摘要

Objective To determine the expression and function of the c-kit receptor in bone marrow mononuclear cells (BMMNC) of patients with myelodysplastic syndromes (MDS). Methods Direct immunofluorescence assay and reverse transcriptase-polymerase chain reaction (RTPCR) were used to detect c-kit protein and c-kit mRNA expressions in the BMMNC of 29 MDS patients and 10 normal controls. Cell culture was used to detect the function of the c-kit receptor. Results c-kit protein expression in the MDS group was significantly higher than that in the control group (8.58％ +5.28％ vs 3.04％ + 1.49％, P＜0.05). c-kit protien expression in the refractory anemia (RA)group was significantly lower than that in the RA with an excess of blasts (RAEB)/RAEB in transformation (RAEB-t) group (5.12％ +2.13％ vs 10.01％ +5.07％, P＜0.05). The rate of c-kit protein expression was 32.43％ in aoute myeloblastic leukemia (AML) cases transformed from MDS (t-AML). c-kit mRNA expression in the MDS group was correlated with c-kit protein expression. Interieukin-3 (IL-3) and erythropoietin (Epo), with or without stem cell factor (SCF), upregulated c-kit protein and its mRNA expression. In the presence of IL-3 and Epo, SCF showed significant stimulating effects on the formation of CFU-GM and BFU-E in semi-solid cultures of normal BMMNC, but had no effects on those of the MDS patients.Conclusion The protein and mRNA expression of the c-kit receptor in the BMMNC of MDS patients were higher than those of normal controls, and the function of this receptor in MDS BMMNC was abnormal. Chin Med J 2001; 114(5) :481-485%目的了解骨髓增生异常综合征(MDS)骨髓单个核细胞c-kit受体的表达与功能。方法采用免疫荧光方法测定c-kit受体蛋白(CD117)的表达；逆转录-聚合酶链反应方法测定c-kit Mrna的表达；细胞培养检测c-kit受体的功能。结果 CD117表达率正常人为3.04％±1.49％，MDS患者为8.58％±5.28％，两者差异有显著性(P＜0.05)；RA患者为5.12％±2.13％)，RAEB/RAEB-t患者为10.01％±5.07％，两者差异有显著性(P＜0.05)；MDS继发白血病患者为32.43％±18.16％。MDS患者c-kit基因Mrna表达与CD117表达相一致。正常骨髓单个核细胞体外半固体培养，在加入造血干细胞因子、白细胞介素-3、红细胞生成素(SCF+IL-3+Epo)后形成的粒-巨噬细胞集落(CFU-GM)较仅加入IL-3+Epo显著增多(P＜0.05)，红系爆式集落(BFU-E)数量极显著增多，且BFU-E体积显著增大(P＜0.01)。MDS患者在上述相同条件下CFU-GM数量无明显变化(P＞0.05)，与正常对照比较，CFU-GM和BFU-E数量均显著减少(P＜0.05)。结论 MDS患者骨髓单个核细胞CD117表达明显高于正常对照，且与病情进展相关；c-kit Mrna表达与CD117表达相一致；MDS患者骨髓单个核细胞体外培养时，SCF协同IL-3、Epo促进造血干/祖细胞增殖分化能力较正常对照明显减弱。该结果提示，MDS患者骨髓造血干/祖细胞c-kit受体表达及功能均异常。