TLR2和TLR4活化的骨髓间充质干细胞对人脐血CD34^+细胞迁移能力的影响  

Influence of TLR2-and TLR4-activated Mesenchymal Stem Cells on Migration of Cord Blood CD34^+ Cells

作　　者：朱云霞[1] 王兴兵[1] 汪健[1] 颜宗海 

机构地区：[1]安徽医科大学附属省立医院血液科,安徽合肥230001

出　　处：《中国实验血液学杂志》2015年第2期512-516,共5页Journal of Experimental Hematology

基　　金：国家自然科学基金(81270573);安徽省级高校自然科学基金(KJ2012Z188)

摘　　要：目的:本研究旨在探讨Toll样受体2(Toll-like receptors 2,TLR2)和TLR4活化对人骨髓源性间充质干细胞(BM-MSC)诱导人脐血CD34+造血干/祖细胞迁移功能的影响及其机制。方法:流式细胞术检测健康供体BMMSC表面TLR2和TLR4的表达情况;TLR2激动剂(PAM3CSK4)和TLR4激动剂(LPS)活化人BM-MSC,收集培养上清,趋化实验测定BM-MSC培养上清对人脐血CD34+细胞的趋化作用;了解TLR2或(和)TLR4的活化对BMMSC诱导CD34+细胞迁移活性的影响。ELISA法定量检测培养上清中趋化因子SDF-1的分泌水平。结果:人BMMSC表面表达TLR2水平分别为(31.5±4.6)%和TLR4(85.6±6.7)%。与未加培养上清的空白组相比,对照组、LPS和/或PAM3CSK4活化的MSC的培养上清对CD34+均有明显趋化作用(P<0.01)。进一步研究显示,与未加激动剂的对照组(MSC上清组)相比,LPS组、PAM3CSK4组、LPS和PAM3CSK4联合刺激组的MSC培养上清诱导CD34+细胞的迁移均有显著促进作用(P<0.05),但LPS组、PAM3CSK4组、LPS和PAM3CSK4联合刺激组的培养上清中,SDF-1浓度与对照组相比未见明显变化(P>0.05)。结论:TLR2和/或TLR4的活化可显著增强骨髓BMMSC诱导人脐血CD34+细胞的迁移作用,但与趋化因子SDF-1无明显关系。Objective： This study was aimed to investigate the possible effect of Toll-like receptors 2 （ TLR2 ） and Toll-like receptors 4 （TLR4） on the migration function of umbilical cord blood （UCB） CD34 ＋ hematopoietic stem/ progenitor cells induced by bone marrow-derived mesenchymal stem cells （MSCs） and to explore the underlying mechanism. Methods： The expression of TLR2 and TLR4 on MSC was detected with flow cytometry. After the MSC were pretreated with TLR2 agonist （PAM3CSK4） and/or TLR4 agonist （LPS）,the supematants were collected. The effect of the supematants on the migration of CD34 ＋ cells was evaluated with chemotaxis assays. Alterations of chemokine （SDF-1） secreted by MSC in the supernatants were assayed by ELISA. Results： The expression levels of TLR2 and TLR4 were （ 31. 5± 4.6 ） % and （ 85.6 ± 6.7 ） % respectively. Compared with the blank group, the migration ability of CD34 cells increased significantly in control, LPS and/or PAM3CSK4 groups （ P 〈 0.01 ）. Further study found that LPS and/or PAM3CSK4 enhanced the chemotactic ability of CD34 ＋ cells （P 〈0.05）, but the concentration of SDF-1 was not changed significantly in all of LPS and/or PAM3CSK4 groups （ P 〉 0.05 ） in comparison with the control group. Conclusion： TLR2 and TLR4 signalings may indirectly increase the migration of CD34＋ hematopoietic stem/progenitor cells by modulating BM-MSC functions, which may not significantly correlate with the production of chemokine SDF-1 by MSCs.

关 键 词：TLR2 TLR4 CD34+细胞 迁移 MSC 

分 类 号：R329.28[医药卫生—人体解剖和组织胚胎学]