colonic vs bone marrow MSC. Mus musculus

We found that mesenchymal stem cells isolated from colonic tissue express significantly increased expression of Ptgs2 or cox-2 compared to that of mesenchymal stem cells isolated from the bone marrow, one of the most common tissues from which this cell type is derived. We hypothesized that the localization of these cells in the colon exposes them to specific environmental factors that induce and/or maintain increased constitutive levels of cox-2 uniquely in this cell type. In order to identify possible candidate molecules regulating cox-2 in these cells, we decided to compare the transcriptomes of colonic mesenchymal stem cells and bone marrow-derived mesenchymal stem cells. Overall design: Mesenchymal stem cells were isolated by fast plastic adherence after collagenase type I-mediated dissociation of the tissue of origin. Cells were maintained in culture in low glucose DMEM with 10mM HEPES and 10% FBS. Cells were passaged at 90-100% confluency. Approximately 4 million cells from four MSC lines, two from colon and two from bone marrow, were lysed between passages 5 and 10. Total RNA was isolated, amplified, and hybridized to Affymetrix MOE230.2 chips.