CD_(34)^+干/祖细胞与纤维连接蛋白的粘附在慢性粒细胞白血病发病中的意义

The significance of the adhesion of CD_(34)^+ stem/progenitor cells to fibronectin in the pathognesis of chronic myelogenous leukemia

目的探讨CD34+干／祖细胞与纤维连接蛋白（FN）的粘附在慢性粒细胞白血病（CML）发病中的作用。方法①采用流式细胞术双标记法检测初治CML慢性期30例和正常骨髓10份CD34+细胞上整合素β1链（CD29）和α4链（CD49d）的表达；②结晶紫染色法观察免疫磁珠分选的CML慢性期5例和5名正常人骨髓CD34+细胞与FN的粘附功能；③极限稀释液体微培养观察FN对正常和CML慢性期骨髓粒细胞-巨噬细胞祖细胞集落（CFU－GM）形成能力的影响。结果①CML慢性期骨髓CD34+细胞CD29和CD49d的表达与正常骨髓比较，差异无显著性；②CML骨髓CD34+细胞与FN的粘附明显低于正常（P＜0．01）；③FN显著抑制正常骨髓CFU-GM的形成（P＜0．01），而对CML骨髓CFU-GM的形成无显著影响。结论CML骨髓CD34+干／祖细胞与FN的粘附功能减弱，因而缺乏FN对祖细胞增殖的调节作用是CML髓系扩增的原因之一。

Objective To investigate the significance of the adhesion of CD34+ stem/progenitor cells to fi-bronectin in the pathogenesis of chromc myelogenous leukemia(CML). Methods ①Integrin β1 chain(CD29) andα4 chain(CD49d) expressions on CD34+ cells were measured by flow cytometry in 30 untreated CML patients inchronic phase (CML-CP) and 10 healthy donors. ②The adhesion function of immunomagnetic beads selected CD34+cells to fibronectin was detected by crystal violet staining in 5 untreated CML-CP patients and 5 healthy donors.③The effect of fibronectin on CFU-GM colony formation of bone marrow cells in 3 CML patients and 3 healthy donorswas observed by limited dilution liquid microculture. Results ①There was no significant difference in CD29 andCD49d expressions on CD34+ bone marrow cells between CML patients and healthy donors. ②The adhesion of CD34+bone marrow cells to fibronectin decreased significantly in CML patients as compared with that in healthy donors(P<0.01). ③The CFU-GM colony formation was significantly inhibited by fibronectin in healthy donors(P<0.01),but not in CML patients. Conclusion The adhesion function abnormality of CML CD34+ bone marrow cells to fi-bronectin may underlie the abnormal proliferation of CML progenitors.