Recombinant adeno-associated virus 2-mediated miRNA-199 suppression vector alleviates dextran sulfate sodium-induced ulcerative colitis in mice.

Aim: Mouse colonic tissue was transfected with a recombinant adeno-associated virus (rAAV) 2 vector. We aimed to determine whether the rAAV vector could mediate gene expression in the colonic tissue and the role of microRNA (miRNA)-199a-5p in regulating the colonic inflammatory response in dextran sulfate sodium (DSS)-treated mice.

Methods: Different transfection methods and transfection times were found to be the most effective for mouse colonic tissue. The rAAV-miRNA-199a-5p vector (and control) was transfected into the colonic tissue of a mouse model of DSS-induced colitis. PCR was used to quantify miRNA and mRNA expression levels, and the TUNNEL assay was used to identify cellular regulation and histological alterations in colonic tissues.

Results: At three weeks following transfection, rAAV produced a higher transfection efficiency in colonic tissues via enucleation than via caudal vein injection and intraperitoneal injection. The colonic inflammatory response and apoptosis in mouse colonic tissues were reduced by miRNA-199a-5p inhibition.

Conclusion: rAAV can be used as a vector to inhibit gene expression in mouse colonic tissues. In mice with colitis, the rAAV-mediated suppression of miRNA-199a-5p reduces the inflammatory response.