摘要
本研究旨在探讨Toll样受体2(Toll-like receptors 2,TLR2)和TLR4激动剂对人脐血CD34+细胞迁移功能的影响及其机制。采用流式细胞术检测脐血CD34+细胞表面TLR2和TLR4的表达情况;用趋化实验和黏附实验观察PAM3CSK4(TLR2激动剂)和LPS(TLR4激动剂)对人脐血CD34+细胞的迁移活性和黏附活性的影响。结果表明:人脐血CD34+细胞表面表达TLR2(14.2±3.8)%和TLR4(19.6±4.1)%。与对照组相比,LPS可明显抑制SDF-1诱导的CD34+细胞的趋化作用(p<0.01),但LPS对CD34+细胞的黏附能力,以及PAM3CSK4对CD34+细胞的趋化和黏附能力均无明显影响。进一步研究显示,LPS对CD34+细胞表面CXCR4的表达无明显影响,但可明显抑制CD34+细胞的自发迁移作用(p<0.05)。结论:TLR4的活化可显著降低SDF-1诱导CD34+细胞的趋化功能,这可能与其抑制CD34+细胞的自发迁移作用具有一定的关系。
This study was aimed to investigate the influence of TLR2 and TLR4 agonists on the migration and adhesion activity of umbilical cord blood（UCB） CD34＋ cells and to explore the underlying mechanism.The expression of TLR2 and TLR4 on UCB CD34＋ cells was detected with flow cytometry.The effect of TLR2 agonist（PAM3CSK4） and TLR2 agonist（LPS） on the migration and adhesion ability of UCB CD34＋ cells was evaluated with chemotaxis and adhesion assays.The results indicated that expression levels of TLR2 and TLR4 were（14.2±3.8）%,（19.6±4.1）% respectively.Compared with the control group,the migration activity of UCB CD34＋ cells toward SDF-1 decreased significantly in LPS group（p〈0.01）.The adhesion activity was not altered significantly in LPS group.However,both the migration activity towards SDF-1 and the adhesion activity of UCB CD34＋ cells were not changed significantly in PAM3CSK4 group.Further study found that LPS did not affect the expression level of CXCR4 on CD34＋ cells,but could inhibit the spontaneous migration ability of CD34＋ cells.It is concluded that TLR4 activation can decrease the chemota-xis function of CD34＋ cells towards SDF-1,which may associate with the decreased spontaneous migration ability of CD34＋ cells.
出处
《中国实验血液学杂志》
CAS
CSCD
2011年第2期469-472,共4页
Journal of Experimental Hematology
基金
国家自然科学基金(30700329)
安徽省优秀青年科技基金(08040106810)
