PDGF-AA promotes MSC migration via BMP-Smad1/5/8 signaling.

<p>A. Transwell experiments and quantitation data. Migration of MSCs was evaluated using a transwell chamber equipped with an 8-µm-pore filter membrane. Cells were plated at 5×10⁴ cells/well in serum-free media onto the upper compartment of the chamber and cultured in the absence or presence of PDGF-AA for 24 h. The filter membrane was removed, fixed with methanol, and stained with 0.1% crystal violet. Lower panel: the number of cells that had migrated to the lower surface of the filter membrane was counted in 5 random fields under a light scope (×200). B. PDGF-AA promotes expression of BMP-Smad1/5/8-controlled genes that regulate cell migration. Primary mouse MSC cells were cultured with or without PDGF-AA for 7 days. To test the effect of BMPRI activation, LDN-193189 was included in the culture medium. Total RNA was isolated from the cells and realtime-PCR was carried out to determine the mRNA levels of genes that are involved in regulating cell migration. Data are means±s.e.m. (n = 3). * p<0.05, **, P<0.01 when compared to empty vectors or untreated cells.