| This study has determined the location of the intestinal stem cells by labeling DNA with 5-bromo, 2'deoxyuridine (BrdU). Based on the assumption that stem cells divide at a slower rate than their proliferating progeny, following a labeling period, cells are permitted to divide. With each cell division, DNA is replicated and the concentration of the pre-existing incorporated BrdU is halved. All rapidly dividing cells dilute the label at a greater rate than the slower dividing stem cells. These stem cells, highly concentrated with BrdU, are then identified. Each crypt was observed to contain one stem.;In order to bulk purify, a non-enzymatic manipulation of the gut was performed. This purification resulted in the release of viable epithelial cells in a sequential manner so as to reflect the gradient of cells from the villus tip to the crypt base.;Fourteen days post-transplant, the tissue was retrieved and the regeneration of intestinal morphology was assessed by the phenotypic characteristics of the newly transplanted cells. (Abstract shortened by UMI.)... |
