1.Effects of mesenchymal stem cells on expansion potential and adhesion molecules expression of cord blood CD34+ cells.
Er-lie JANG ; Zheng ZHOU ; Yong HUANG ; He-hua WANG ; Mei WANG ; Qing-guo LIU ; Shi-yong ZHOU ; Zhang-song YAN ; Wen-jing ZHAI ; Ming-zhe HAN
Chinese Journal of Hematology 2005;26(7):397-400
OBJECTIVETo explore the effects of bone marrow mesenchymal stem cells (MSCs) on in vitro expansion potential, the adherent molecules expression of cord blood (CB) CD34(+) cells.
METHODSMSCs were obtained from human bone marrow and their differentiation function and phenotype were identified. CB CD34(+) cells were expanded in culture systems with or without MSC layer. Hematopoietic progenitor cells and adhesion molecules expression were assessed by semisolid culture assay and flow cytometry.
RESULTSThy-1, SH2, SB10, CD44, CD13, CD49e and CD29 were highly expressed on MSCs with no expressions of CD34, CD45, HLA-DR, CD14 and CD31. The MSCs could differentiate into adipocytes and osteoblasts under specific induction conditions. After culturing on MSCs layer with supplement of cytokines for 8 days, the absolute numbers of nuclear cells, CD34(+), CD34(+)CD38(-), CD34(+)CD62L(+) cells and CFU-Cs were increased by 145.57 +/- 17.89, 37.47 +/- 13.78, 69.78 +/- 50.07, 10.74 +/- 5.89 and 20.73 +/- 5.54-folds, respectively, being significantly higher than that cultured with cytokines alone. The expression of ALCAM, VLA-alpha4, VLA-alpha5, VLA-beta1, HCAM, PECAM and LFA-1 on CD34(+) cells remained unaffected. The expressions of ICAM-1 and L-selectin were downregulated during expansion, while the absolute numbers of CD34(+)CD62L(+) and CD34(+)CD54(+) cells were increased.
CONCLUSIONSMSCs layer improves expansion of CB CD34(+) cells while inhibiting their differentiation and retaining their homing ability.
Antigens, CD34 ; Cell Adhesion Molecules ; metabolism ; Cell Differentiation ; Cell Proliferation ; Cells, Cultured ; Fetal Blood ; cytology ; Hematopoietic Stem Cells ; cytology ; metabolism ; Humans ; Mesenchymal Stromal Cells