MicroRNA-221 controls expression of intercellular adhesion molecule-1 in epithelial cells in response to XXXX infection.

@entity1 @entity11447 @entity66 @entity2036 @entity1373 @entity4316 @entity2432 @entity2071
@entity2432 is a protozoan parasite that infects gastrointestinal epithelial cells and causes @entity66 in @entity1 and animals globally. Pathological changes following @entity2432 infection include crypt @entity1373 and a modest inflammatory reaction with increased infiltration of lymphocytes into intestinal mucosa. Expression of adhesion molecules, such as intercellular adhesion molecule-1 ( @entity2071 ), on infected epithelial cell surfaces may facilitate adhesion and recognition of lymphocytes at infection sites. MicroRNAs (miRNAs) are small RNA molecules of 23 @entity2036 that negatively regulate protein-coding gene expression via translational suppression or mRNA degradation. We recently reported that microRNA-221 (miR-221) regulates @entity2071 translation through targeting the @entity2071 3'-untranslated region (UTR). In this study, we tested the role of miR-221 in regulating @entity2071 expression in epithelial cells in response to @entity2432 infection using an in vitro model of @entity1 @entity11447 . Up-regulation of @entity2071 at both message and protein levels was detected in epithelial cells following @entity2432 infection. Inhibition of @entity2071 transcription with @entity4316 could only partially block @entity2432 -induced @entity2071 expression at the protein level. @entity2432 infection decreased miR-221 expression in infected epithelial cells. When cells were transfected with a luciferase reporter construct covering the miR-221 binding site in the @entity2071 3'-UTR and then exposed to @entity2432 , an enhanced luciferase activity was detected. Transfection of miR-221 precursor abolished @entity2432 -stimulated @entity2071 protein expression. In addition, expression of @entity2071 on infected epithelial cells facilitated epithelial adherence of co-cultured Jurkat cells. These results indicate that miR-221-mediated translational suppression controls @entity2071 expression in epithelial cells in response to @entity2432 infection.
