Khalil PN et al. (2007) Nonmyeloablative stem cell therapy enhances microcirculation and tissue regeneration in murine inflammatory bowel disease. Gastroenterology 132: 944–954

IBD is managed by the use of immunomodulatory and anti-inflammatory drugs, but repair to the damaged digestive tract by other means is still required. Adult stem cell therapy seems to contribute to tissue regeneration in inflammatory-related diseases. Khalil et al., therefore, investigated the potential of treatment with nonmyeloablative stem cells (CD34− cells) to facilitate epithelial repair in a mouse model of IBD.

Moderate or severe colitis was induced in adult mice in two cycles, each comprising addition of dextran sulphate sodium (DSS) to drinking water at a concentration of either 3% (n = 30) or 5% (n = 36) for 7 days, followed by a 10-day recovery period. On day 8, 2.0 × 106 mouse CD34− cells (from an immortalized cell line) were injected into the tail vein of these mice and the mice from one of two control groups (each n = 9) that received no DSS. Mice were observed during treatment for a period of 35 days. Stem cell therapy significantly reduced the histological grade and morphological signs of mouse colitis, and, in the 5% DSS group, significantly increased survival of mice with severe colitis. The injected CD34− cells were seen to home to areas of damaged colon, but not undamaged regions, and promote neovascularization. Differentiation of the injected stem cells into endothelial cells to improve mucosal perfusion was noted.

Stem cell therapy seemed to accelerate tissue repair, which might be related to improved perfusion supporting pre-existing intestinal stem cell function.