FIG. 3.
Overexpression of ICAM-1 in MSCs by gene transfection inhibited their osteogenic differentiation in vitro. As shown in (A), the percentage of green fluorescent MSCs was observed by fluorescence microscopy. The polybrene-mediated virus infection efficiency was more than 95%. Real-time PCR data showed that the expression of ICAM-1 mRNA significantly increased after infection (B). Immuno-phenotyping showed that the positive rate of ICAM-1 protein expression significantly increased from 0.5% before infection to 94% after infection (C). In situ ALP and von Kossa staining showed that compared with control cells, osteogenic activity of ICAM-1high MSCs was remarkably suppressed (D). Moreover, real-time PCR results showed the Runx2 and OCN mRNA expression decreased sharply (E, F). After ICAM-1 targeted RNAi, both ALP activity and bone matrix mineralization were partially rescued (G). In addition, the mRNA expression of Runx2 and OCN recovered when ICAM-1 was knocked down (H, I). (*p<0.05, **p<0.01) Scale bars represent 100 μm (A, D, G). Color images available online at www.liebertpub.com/tea