Correction: BMP-Non-Responsive Sca1⁺CD73⁺CD44⁺ Mouse Bone Marrow Derived Osteoprogenitor Cells Respond to Combination of VEGF and BMP-6 to Display Enhanced Osteoblastic Differentiation and Ectopic Bone Formation

Correction: BMP-Non-Responsive Sca1+CD73+CD44+ Mouse Bone Marrow Derived Osteoprogenitor Cells Respond to Combination of VEGF and BMP-6 to Display Enhanced Osteoblastic Differentiation and Ectopic Bone Formatio

The D1 cells do not express CD105, Alk1 and Alk6 receptors.

<p>Using labeled monoclonal antibodies expression of stem cell markers (A) was determined by flow cytometry. Expression of VEGF and BMP receptors was determined by PCR followed by agarose gel electrophoresis (B).</p

BMPs do not enhance mineralization.

<p>The mineralization of D1 cells was measured quantitatively using alizarin red staining. The cells were stained at day 7, 14 and 21 using alizarin red (left panel). The dye was extracted and intensity of color was quantified at 405 nm using a spectrophotometer (right panel).</p

The D1 cells are multipotent.

<p>The D1 cells were stained with DAPI and phalloidin to visualize cell morphology (A). Osteogenesis was assayed by staining with Alizarin Red (B) and adipogenesis was assayed by staining with Sudan IV (C).</p

List of antibodies used for fluorescence activated cell sorting.

<p>List of antibodies used for fluorescence activated cell sorting.</p

List of primers used in real time PCR.

<p>List of primers used in real time PCR.</p

Combination of VEGF and BMP-6 enhances expression of osteogenic genes.

<p>Expression of ALP (A), COL1A1 (B), runx2 (C) and osterix (D) genes were determined by real time PCR at day 7. * denotes p<0.05.</p

Preconditioning of BMP-non-responsive D1 cells with VEGF and BMP-6 enhances their ability to induce ectopic bone formation.

<p>The bone density of harvested implants was measured by radiography and Image J software (A-C). Representative images are shown in the figure. H and E staining revealed typical histology of bone (E). Real time PCR showed modulation of RANKL/OPG ratio (D). * denotes p<0.05 compared with OM group at weeks 2.</p

Expression of ALP and COL1 genes and genes for transcription factors osterix and Dlx5 in the implants of D1 cells.

<p>mRNA expression was quantified using gene specific primers and real time PCR. cDNA prepared from RNA isolated from the harvested implants was used as the template. * denotes p<0.05 compared with OM group of the respective time point, unless indicated otherwise by the horizontal lines.</p

List of primers used in PCR.

<p>List of primers used in PCR.</p