Knockdown of p38 and ERK1/2 leads to opposing effects on BMP9-indcued ectopic bone formation.

<p>(<b>A</b>) Co-infection efficiency of Ad-BMP9 and AdR-si-p38 (or AdR-si-ERK1/2). C3H10T1/2 cells were co-infected with Ad-BMP9 and AdR-si-p38 (or AdR-si-ERK1/2). At 24 hrs post co-infection, the co-infection efficiency was determined under a fluorescence microscope. (<b>B</b>) Macrographic images of ectopic bone mass. (<b>C</b>) Total volume of retrieved samples. “**”, p<0.01 (<i>vs.</i> control groups) (<b>D</b>) Histological stains of retrieved samples. Retrieved tissues were decalcified, fixed in 10% formalin overnight, and embedded in paraffin. Serial sections of the embedded specimens were stained with H&E, Masson’s Trichrome stain and Alcian Blue stain. BM, Bone Matrix; Ch, Chondrocyte; UMPCs, Undifferentiated mesenchymal progenitor cells; CM, Cartilage Matrix. Magnification, ×150.