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 kitmRNA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 0 4 %± 1 4 9% ,MDS患者为 8 58%± 5 2 8% ,两者差异有显著性 (P <0 0 5) ;RA患者为 5 12 %± 2 13% ) ,RAEB RAEB t患者为 10 0 1%± 5 0 7% ,两者差异有显著性 (P <0 0 5) ;MDS继发白血病患者为 32 4 3%± 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 0 5) ,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 0 1)。MDS患者在上述相同条件下CFU GM数量无明显变化 (P >0 0 5) ,与正常对照比较 ,CFU GM和BFU E数量均显著减少 (P <0 0 5)。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 kitmRNA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