Evaluation of Inhibitory Effect of Abatacept (CTLA4-ig) and Conditioned Medium of Mesenchymal Stem Cell in an Acetic Acid-induced Mouse Model of Acute Colitis.

An individual with a genetic predisposition to inflammatory bowel disease (IBD) can experience inflammatory responses leading to conditions such as Crohn's disease (CD) or Ulcerative colitis (UC). Currently, stem cell therapies, particularly those utilizing mesenchymal stem cells (MSCs), are gaining attention due to their immunomodulatory properties, as demonstrated in clinical trials. Consequently, we decided to investigate the effects of mesenchymal stem cells-conditioned medium (MSC-CM) and Abatacept in an experimental model of acute colitis. MSC-CM was extracted from female BALB/C mice and stored for future use. Acute colitis was induced in BALB/C mice through the intrarectal administration of 100 µL of 4% acetic acid. Following this procedure, CM and Abatacept were administered intraperitoneally. Throughout the study, various parameters were monitored, including changes in body weight, bleeding, stool consistency, disease activity index (DAI), mortality rate, as well as the weight and length of the colon. Histopathological analyses were also conducted, along with monitoring changes in the levels of IL-10 and IFN-γ. The data collected are presented as mean ± SD and were analyzed using One-Way ANOVA. According to the results of the study, CM with and without Abatacept significantly reduced weight loss and bleeding as well as improved fecal consistency and DAI. Macroscopic examination of the colon showed that after infusion, colon length was reduced and histopathological analysis showed a decrease in mucosal changes. The secretion of IL-10 was increased while the IFN-γ level was reduced. Research indicates that the immunomodulatory properties of MSC secretion can have positive effects. We propose a combination therapy with MSC, which we believe could lead to improved outcomes in the treatment of acute colitis.