Human platelet lysates as an alternative to fetal bovine serum for the culture of mesenchymal stem cells

Abstract

Objective To investigate the impact of human platelet lysates (HPL) on the morphology,proliferation,cell surface markers,and differentiation capacity of umbilical cord-derived mesenchymal stem cells (UC-MSCs).Methods Cord blood was collected from umbilical cord after the delivery of placenta.Four buffy coat units and one serum unit were pooled and frozen at-20 ℃.After two freeze-thaw cycles,at least 10 units of freeze-thaw lysed human platelets were further pooled to yield HPL.UC-MSCs were isolated and cultured in medium containing either 10％ HPL or fetal bovine serum (FBS).To compare the effect of HPL on MSCs expansion,the 30 d cumulative population doublings were determined,UC-MSCs were maximally expanded,and the number of cells cultured in six-well plate for 6 d was counted.Cell surface antigen phenotyping was performed with UC-MSCs cultured in either 10％ HPL or 10％ FBS at passage 3.The effect of HPL on the differentiation capacity of UC-MSCs was also examined.Resuits HPL has no effect on the morphology of UC-MSCs ; as shown by spindle-like cells at passage 3.The 30 d cumulative population doublings were statistical comparable between HPL and FBS.However,the number of cells maximally expanded at passage ten in HPL [(7.5 ±0.4) × 106] cells was much greater than in FBS [(4.3 ±0.2) × 106] cells.After culturing for 6 d,cell number/well in the HPL group was greater than the FBS group (P ＜ 0.05).UC-MSCs were strongly positive against CD44,CD73,CD90,and CD105; whereas they were negative for CD11b,CD19,CD 31,CD34,CD45,or Human leukocyte antigen-DR (HLA-DR).No significant differences between HPL and FBS were detected.UC-MSCs derived from both HPL and FBS demonstrated differentiation toward the osteogenic,adipogenic,and chondrogenic lineages.Conclusion HPL may be considered as an alternative to FBS for the culture and expansion of UC-MSCs in vitro.HPL favors very rapid expansion while maintaining the morphology,cell surface markers,and differentiation capacity. Key words: Umbilical cord-derived mesenchymal stem cells;  Human platelet lysates;  Proliferation;  Surface markers ;  Differentiation