细胞因子短期扩增对造血干／祖细胞黏附和迁移能力的影响

Effect of ex vivo short time expansion with SCF and IL-6 on the adhesion and transmigration activities of hematopoietic stem/progenitor cells

目的:探讨干细胞因子(SCF)+白细胞介素-6(IL-6)短期扩增对CD34+造血干/祖细胞黏附和迁移能力的影响。方法:用密度剃度离心的方法分离脐血CD34+细胞,经SCF和IL-6孵育48 h,用CCK-8方法检测CD34+细胞增殖能力;用流式细胞仪检测处理前后的CD49d(VLA-4)、CD11 a(LFA-1)、CD62L(L-selectin)及CD184(CXCR4)的表达。用纤连蛋白(FN)包被96孔板,检测经或未经因子扩增的CD34+细胞的黏附能力。扩增的CD34+细胞悬浮于transwell培养板的上层,下层添加基质细胞衍生因子(SDF-1),流式细胞仪检测迁移细胞数,计算迁移率。结果:经SCF+IL-6处理48h后CD34+细胞扩增近3倍;表达CD49d、CD11 a、CD62L及CD184的CD34+细胞的百分数分别由原来的26.34%±5.37%、17.63%±4.57%、46.38%±6.61%和9.58%±1.56%增加到65.67%±8.72%、56.67%±6.34%、84.76%±9.57%和19.32%±3.64%(P<0.01)。扩增后的CD34+细胞对FN的黏附能力及在SDF-1诱导下的迁移作用都显著增强(P<0.01)。结论:SCF+IL-6短期扩增CD34+造血干/祖细胞显著增加细胞的黏附能力,增加SDF-1诱导的迁移作用,可能是SCF+IL-6促进归巢的主要机制之一。

AIM： To investigate the expression and function of homing related molecules and transmigration a- bility of human cord blood CD34^＋ hematopoietic stem/progenitor cells after short time stimulation with cytokine SCF and IL - 6. METHODS： CD34^＋ cells were separated by Ficoll density gradient centrifugation and stimulated by SCF and IL - 6 cytokines for 48 h. The changes of CD49d （VLA -4） , CD11a （ LFA - 1 ） , CD62L （ L - selectin） and CD184 （CXCR4） were analyzed by flow cytometry. The adherent and migration activities of CD34^＋ cells were evaluated in human fibronectin （FN） coated microplates （96 wells） and transwell system. RESULTS： The numbers of CD34^＋ cell expanded to 3 folds and the percentages of CD34^＋ cells that were positive expressions for CD49d, CDlla, CD62L or CD184 increased 1 to 2 folds after the cytokine stimulation. The spontaneous adhesion between CD34^＋ , FN and SDF - 1 induced migration increased after SCF ＋ IL -6 stimulated. CONCLUSION： SCF ＋ IL -6 can improve the most of the homing related characteristics and activities in the short time expansion of CD34^＋ hematopoietic stem/progenitor cells, which may be partly related to the increased intrinsic homing potential.