Project description:Despite the high prevalence of gastric diseases like gastric cancer and peptic ulcer disease, largely attributed to Helicobacter pylori infections, an understanding of the underlying mechanisms remains limited. Current in vitro models suffer from poor physiological relevance and limitations in live, long-term observations and experimental access. In this study, we introduce a homeostatic human gastric organoid-on-a-chip system with bilateral access, capable of modelling H. pylori niche establishment and persistent colonization of the gastric epithelium.We show that in physiological apical acidic conditions, the model is able to generate mature pit cells, which are absent in traditionally grown organoids. Upon infection with H. pylori for up to 6 days, these mature pit cells exhibit a distinctive response, contrary to existing paradigms. Beyond its immediate relevance for studying H. pylori infection, this model with structurally and functionally increased relevance holds broader significance by providing a versatile platform to advance our understanding of gastric epithelial cell interactions as well as gastric mucosal immunity and host-pathogen interactions.
Project description:Helicobacter pylori infection can induce gastric pathologies ranging from chronic gastritis to peptic ulcers and gastric cancer. Individuals´ response to H. pylori infection is complex and it depends on a combination of environmental factors, genetic background, host response and strain virulence. The pathway towards gastric cancer is a sequence of events known as the Correa's model of gastric carcinogenesis, a stepwise inflammatory process from normal mucosa to chronic active gastritis, atrophy, metaplasia and finally gastric adenocarcinoma. This study explores gastric clinical specimens representing different steps of the Correa pathway with the aim of identifying the expression profile of coding- and non-coding RNAs (microRNAs and small RNAs) which may have a role in the Correa's model of gastric carcinogenesis and potentially develop novel clinical biomarkers. We screened for differentially expressed genes in gastric biopsies (antrum/corpus) by employing RNAseq (for microRNAs and non-coding RNAs) and microarrays (for coding RNAs).
Project description:Helicobacter pylori infection can induce gastric pathologies ranging from chronic gastritis to peptic ulcers and gastric cancer. Individuals´ response to H. pylori infection is complex and it depends on a combination of environmental factors, genetic background, host response and strain virulence. The pathway towards gastric cancer is a sequence of events known as the Correa's model of gastric carcinogenesis, a stepwise inflammatory process from normal mucosa to chronic active gastritis, atrophy, metaplasia and finally gastric adenocarcinoma. This study explores gastric clinical specimens representing different steps of the Correa pathway with the aim of identifying the expression profile of coding- and non-coding RNAs (microRNAs and small RNAs) which may have a role in the Correa's model of gastric carcinogenesis and potentially develop novel clinical biomarkers. We screened for differentially expressed genes in gastric biopsies (antrum/corpus) by employing RNAseq (for microRNAs and non-coding RNAs) and microarrays (for coding RNAs).
Project description:Helicobacter pylori infection can induce gastric pathologies ranging from chronic gastritis to peptic ulcers and gastric cancer. Individuals´ response to H. pylori infection is complex and it depends on a combination of environmental factors, genetic background, host response and strain virulence. The pathway towards gastric cancer is a sequence of events known as the Correa's model of gastric carcinogenesis, a stepwise inflammatory process from normal mucosa to chronic active gastritis, atrophy, metaplasia and finally gastric adenocarcinoma. This study explores gastric clinical specimens representing different steps of the Correa pathway with the aim of identifying the expression profile of coding- and non-coding RNAs (microRNAs and small RNAs) which may have a role in the Correa's model of gastric carcinogenesis and potentially develop novel clinical biomarkers. We screened for differentially expressed genes in gastric biopsies (antrum/corpus) by employing RNAseq (for microRNAs and non-coding RNAs) and microarrays (for coding RNAs).
Project description:Helicobacter pylori is a highly successful and important human pathogen that causes chronic gastritis, peptic ulcer diseases and gastric cancer. Innate immunity plays an important role of the primary defense against pathogens and epidemiological studies have suggested a role of toll-like receptor 1 (TLR1) in the risk of H. pylori acquisition. We performed microarray analysis of gastric mucosal biopsy specimens from H. pylori-positive and uninfected subjects; infection was associated with an ~15-fold up-regulation of TLR10 (p <0.001). Quantitative RT-PCR confirmed TLR10 mRNA levels were increased 3-fold in H. pylori-infection (p <0.001) and immunohistochemistory using anti-TLR10 polyclonal antibodies showed increased TLR10 expression in gastric epithelial cells of infected individuals. In vitro experiments where H. pylori was co-cultured with NCI-N87 gastric cells showed significant H. pylori-specific up-regulation of TLR10 mRNA levels and a correlation with TLR2 mRNA levels (R = 0.87, P <0.001). We compared combinations of TLRs for their ability to mediate NF-_B activation. NF-_B activation was increased following exposure to heat killed H. pylori or H. pylori-LPS only with the TLR2/TLR10 heterodimer. These findings suggest TLR10 is a functional receptor involved in the innate immune response to H. pylori infection and that TLR2/TLR10 heterodimer possibly functions in the recognition of H. pylori-LPS.