Positively Correlated CD47 Activation and Autophagy in Umbilical Cord Blood-Derived Mesenchymal Stem Cells during Senescence

Figure 2

CD47 expressions and cellular senescence on late passages of UCB-MSCs were downregulated. (a) Flow cytometric analysis of CD47 expressions on UCB-MSCs during passaging was performed. (b) Representative immunofluorescence images of CD47-positive cells under passaging from passage 4 to 13. Scale bar 20 μm. (c) Cell proliferation was determined by measuring fold changes, with results normalized to the growth observed at passage 4. (d) SA β-gal staining was performed on UCB-MSCs at passages 4, 7, and 13. SA β-gal positive cells were quantified by determining the percentages of stained cells. Scale bar 50 μm. (e) Representative western blots of CD47, pRB, and pp38, cellular senescence-related markers, in UCB-MSCs subjected to passaging the cells. Semiquantification of protein expression levels of CD47, pRB, and pp38 was analyzed at passage 4 (P4), passage 7 (P7), and passage 13 (P13). Data is expressed as the ; ; , .

(a)

(b)

(c)

(d)

(e)