Study the effects of mesenchymal stem cell conditioned medium injection in mouse model of acute colitis.

Background And Aim: Inflammatory bowel disease (IBD) is an autoimmune-inflammatory disorder that results in inflammatory responses in individuals who are genetically susceptible. Uncontrolled inflammation in Crohn's disease (CD) or Ulcerative colitis (UC) affects the patient quality of life. Current therapies are not completely effective while cell therapy, especially the treatment with mesenchymal stem cells (MSCs) absorb lots of attention due to its immunomodulatory properties. So, we examined the effects of mesenchymal stem cells-conditioned medium (MSC-CM) in the experimental model of acute colitis.

Material And Method: MSC-CM was isolated from C57Bl/6 male mice and stored. The acute colitis induction in C57BL/6 mice was performed by dissolving dextran sulfate sodium (DSS) in drinking water and then CM injected intraperitoneally. During the study body weight changes, bleeding, stool consistency, disease activity index (DAI), mortality rate, weight and length of the colon and histopathological analysis were recorded as well as changes in the percentage of Treg cells. The level of IL-17, IL-10, and TGF-β were measured, too. Data were reported as mean±SD and analyzed by One-Way ANOVA test.

Results: Based on the results it is recognized CM inhibited the weight loss and bleeding and improved fecal consistency and DAI. Macroscopic examination of the colon showed that after infusion, colon inflammation was reduced and histopathological analysis showed a decrease in mucosal degeneration. The percentage of Treg cells, secretion of IL-10 and TGF-β was increased while the IL-17 level was reduced.

Conclusion: This study showed that mesenchymal stem cell secretion with immunomodulatory properties has the potential to reduce inflammatory responses.