CD105- biotin- avidin promoting synovium- derived mesenchymal stem cells adhesion and selection

Abstract

Objective To observe the CD105- biotin- avidin promoting synovium- derived mesenchymal stem cells(SMSCs)adhesion and selecting CD105- positive cells in the cartilage tissue engineering, and evaluate its effects on cartilage formation. Methods SMSCs were obtained by enzyme digestion.Flow cytometry was used to detect markers on cell surface, including CD29, CD34, CD44, CD45, CD90 and CD105.With divided 3 groups(A:untreated+ cells; B:avidin+ biotin- cells; C:avidin+ CD105- biotin - cells), adhesion cell number was counted by absorbance and random field count at different time point.CD105- positive cells were tested through immunofluorescence. After 3 weeks chondrogenic induction, hematoxylin- eosin(HE), alcian blue staining and immunofluorescence were used to assess chondrogenesis. Results SMSCs showed star or spindle shape with adherent growth. The expression of CD29, CD44 and CD90 was positive, while CD34 and CD45 negative.The positive rate of CD105 was about 42%.Compared with Group A, Group B and C significantly increased cells adhesion at 1 and 2 h(P< 0.05). Although Group B had more cells than C, there was no statistical difference.Immunofluorescence showed CD105- positive cells in Group C were significantly higher than that in Group B and A.After chondrogenic induction, while proteoglycan and typeⅡcollagen were observed in all groups, there was most cartilage specific extracellular matrix in Group C. Con-clusion CD105- biotin- avidin system could not only enhance cells adhesion, but also select CD105 - positive cells, which may promote chondrogenesis better. Key words: CD105; Biotin-avidin; Synovium-derived mesenchymal stem cells; Cartilage tissue engineering