The expression of innate immunity genes in Italian Crohn disease patients

Abstract

Crohn’ disease (CD) is a chronic idiopathic inflammatory bowel disease characterized by the interaction of both hereditary and environmental factors. Intestinal flora and pathogens such as bacteria, viruses and fungi, are thought to be the first step leading to an inflammatory status, which is subsequently amplified in genetically susceptible patients thus triggering the disease. Since the innate immune system is believed to be very important in regulating the flora of the gastrointestinal tract, we decided to study the influence of two important molecules of the innate immune system in CD. Frozen intestinal biopsies from 49 Crohn patients and 10 healthy individuals were collected at the gastroenterology unit of Children’s Hospital Burlo Garofolo in Trieste and innate immunity gene expression was evaluated by using both in situ RT-PCR and quantitative PCR. We have analyzed the expression and localization of both MBL2 and DEFB1 genes in intestinal biopsies of Italian Crohn patients by in situ RT-PCR and quantitative PCR. DEFB1 is expressed equally in all subjects. Importantly, MBL2 transcripts were upregulated in CD patients compared to healthy controls. MBL2 expression in controls is normally extremely low, detectable only by quantitative PCR with a Taqman probe. We demonstrated the MBL2 and DEFB1 expression in intestinal biopsies of patients suffering from CD. Our results showed that the MBL2 gene is expressed by cells in the basal lamina, whilst DEFB1 is expressed by epithelial cells.