抑制性受体LAIR-1对巨核谱系分化的调节作用

摘要

Objective To study the expression of inhibitory receptor LAIR-1 on the megakaryocytic lineage cells and the regulatory effect of LAIR-1 on the differentiation of megakaryocytes ( MKs). Methods Flow cytometry ( FCM) and laser confocal microscopy were used to detect the expression of LAIR-1' on the megakaryocytic lineage cells. Cord blood CD34+ cells were purified by a positive selection using an immunomagnetic separation system. The CD34+ cells were induced to differentiate to MKs by serum-free medium system in vitro. LAIR-1 was activated by cross-linking with antibody or ligand and then the effect of LAIR-1 on the differentiation of MKs was detected. Results LAIR-1 was expressed on the surface of CD34+ CD41a + and CD41a+ CD42b+ cells in the bone marrow of human. In human cord blood, the surface expression of LAIR-1 is detectable in CD34+ CD41a- and CD34 + CD41a+ cells. When cord blood CD34+ cells were induced to megakaryocytic differentiation, LAIR-1 presented in immature CD41a+ cells with cell ploidy of 2N and 4N. Cross-linking of LAIR-1 appeared to inhibit the differentiation of MKs from cord blood CD34+ cells. Conclusions LAIR-1 is a new potential negative regulatory molecule participating in the early-stage differentiation of MKs.%目的 研究抑制性受体LAIR-1在巨核谱系细胞的表达及其对巨核细胞分化的调节作用.方法 采用流式细胞术和激光共聚焦显微镜检测LAIR-1在巨核谱系细胞的表达；免疫磁珠法纯化脐血CD34+细胞,体外无血清培养系统诱导CD34+细胞向巨核细胞分化,观察LAIR-1被抗体或配体交联激活后对巨核细胞分化的影响.结果 LAIR-1表达于人骨髓CD34+ CD41a+和CD41a+ CD42b+细胞以及脐血CD34+ CD41a -和CD34+ CD41a+细胞；脐血CD34+细胞向巨核细胞分化过程中,LAIR-1表达在倍性为2N和4N的不成熟CD41a+细胞上；交联激活LAIR-1分子能够抑制脐血CD34+细胞向巨核细胞的分化.结论 LAIR-1可能是参与巨核细胞早期分化发育的一种新的负调控分子.