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

Figure 4

CD47 knockdown in UCB-MSCs reduces the autophagy and accelerates the senescence. (a) Flow cytometric analysis showed CD47-silenced UCB-MSCs downregulated CD47 cell surface markers at passage 6. (b) Human autophagy array was performed to reveal the significant autophagy-related protein level difference between control and CD47-silenced UCB-MSCs. Relative fold changes were normalized to control siRNA-transfected cells. Red box with arrow indicated LC3B proteins, showing significant difference. (c, d) Representative western blot analysis demonstrated relative changes of senescence-related proteins (pRB and pp38) and autophagy-related proteins (ATG5, ATG12. Beclin1, and LC3B) after CD47 siRNA transfection at passage 6. (e) Proliferation at day 5 after CD47 siRNA transfection was downregulated. (f) Immunostaining results with LC3B and CD47 antibodies on control siRNA and CD47 siRNA-transfected UCB-MSCs were determined. Scale bar 20 μm. Data is expressed as ; ; .

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