Figure 3. Effect of IL-6 knockdown on the osteoblastic markers induced by BMP9 in MEFs. (A) Effect of BMP9 and/or IL-6 knockdown on RUNX2 protein level were measured using western blot assay. (B) Western blot assay quantification shows the effect of BMP9 and/or IL-6 knockdown on RUNX2 protein level. (C) Effect of BMP9 and/or IL-6 knockdown on ALP activity was measure using histochemical stain. (D) Quantification of histochemical stain shows the effect of BMP9 and/or IL-6 knockdown on ALP activity. (E) Effect of BMP9 and/or IL-6 knockdown on OPN mRNA expression was measured using real-time PCR assay. (F) Western blot assay shows the effect of BMP9 and/or IL-6 knockdown on OPN protein level. (G) Quantification results of western blot assay show the effect of BMP9 and/or IL-6 knockdown on OPN protein level. (H) Effect of BMP9 and/or IL-6 knockdown on mineralization was measured using Alizarin Red S stain. (I) Quantification of Alizarin Red S stain show the effect of BMP9 and/or IL-6 knockdown on mineralization. (** P < 0.01).