Einfluss proinflammatorischer Zytokine auf die Expression von humanem ß2-Defensin in Darmepithelien — In-vitro-Untersuchungen im Modell mit der epithelialen Zelllinie HT-29

In Crohn’s disease an altered intestine mucosal barrier and cellular cytokine-mediated immune responses against commensal flora was described before. Taking part in the barrier function, human β2-defensin (HBD-2) is transcriptionally regulated but its induction mechanisms are poorly understood. Effects of proinflammatory cytokines on HBD-2 expression were studied on transcriptional and protein level in the human epithelial cell line HT-29. The induction of HBD-2-specific mRNA by interleukin-1β supports the hypothesis, that defensin production might not only be regulated by exogenous triggers but by cell products. While sensitive for low amounts of recombinant native HBD- 2, Western blot analysis did not reveal HBD-2 protein in HT-29 cells and cell culture supernatants. Using a recombinant fusion protein of HBD-2 and a green fluorescent protein constitutively expressed and secreted by transfected HT-29-cells, methods to study HBD-2 in vitro in a cellular context can be improved.