ABSTRACT
Objective Comparing biological characteristics and the roles in repairing of intestinal irradiation injury of bone marrow derived Flk-1+ MSCs and small intestinal derived SP cells.Methods Phenotypes of the two cell population were determined by flow cytometery.Flk-1+ MSCs and intestinal SP cells were infused into irradiated mice,distribution and differentiation of these cells were determined.Histopathological change and fibrosis were evaluated.Results The phenotypes of Flk-1+ MSCs and intestinal SP cells were quite different.Both Flk-1+ MSCs and intestinal SP cells could home to injury tissue rapidly,participate intestinal epithelial repair,and alleviate fibrosis and collagen deposition after irradiation.SP cells mostly engrafted into intestinal epithelium,while Flk-1+ MSCs partly engrafted into interstitial region as well as epithelium.Conclusion Flk-1+ MSCs and intestinal SP cells may alleviate symptoms effectively,though their mechanisms are disparite.
ABSTRACT
Objective: To investigate the nutritious effects of IGF, HGF and Gln on intestinal mucosal precursor cells in vitro.Methods: Different combinations of IGF,HGF and Gln were used to observe their effects on the expansion and development of the cultured intestinal mucosal precursor cells.Results: The combination of IGF,HGF and Gln could markedly promote the expansion of cultured intestinal mucosal precursor cells.Although IGF or HGF alone could promote the expansion of intestinal mucosal precursor cells, they had little effects on the development.On the contrary,Gln alone can promote the development of intestinal mucosal precursor cells,but it had little effects on their expansion.Conclusion: IGF,HGF or Gln alone has little effects on the expansion and development of the intestinal mucosal precursor cells.When they are used together,they can efficiently provide the essential stimuli for the expansion of the cultured intestinal mucosal precursor cells in vitro and enable the recombination of the different cells and formation of intestinal mucosa-like structure in vitro.
ABSTRACT
Objective: To investigate the mechanism underlying the repairing effect of Flk-1+ MSC on injury.Methods: We established the mouse model of acute renal ischemia-reperfusion,perfused murine Flk-1+ MSC within 1 hour or after 10 days in the acute and chronic groups,respectively,determined the homing of GFP positive Flk-1+ MSCs and the percentage of proliferating cells in the injured renal tissues by immunohistochemistry,and identified chronic fibrosis after injury by Masson trichrome staining. Results: Tissue injury and inflammation were significantly alleviated in the acute group,exhibiting a good long-term recovery,but no significant improvement was observed in the chronic group.The number of PCNA positive cells reached the peak at 3 days in the acute group,as compared with 10 days in the control,indicating that MSC engraftment effected an earlier endogenous repair.GFP staining showed that most of the MSCs homed to the interstitial region and the rest to the renal tubule.Conclusion: Flk-1+ MSC has a repairing effect on renal injury via alleviating acute inflammation and launching endogenous repair,while direct differentiation from Flk-1+ MSC is not the primary mechanism of its therapeutic efficacy.