Figure 6. Primary response of gastric organoids to H. pylori infection.
(A) Scheme and brightfield image of microinjection of H. pylori into an organoid (left). Confocal image of infected organoid (Lumen infected, LI) and non-infected organoid (NI) (right). Bacteria were visualized with using GFP-expression, organoids were counterstained with E-Cadherin (red) and DAPI (blue). (B) Electron microscopy demonstrates close interaction of bacteria with epithelial cells. Arrows indicate the binding site (C) Differential gene expression upon infection of human gastric organoids. Genome-wide microarray was performed on 3 independent experiments using organoids derived from 3 patients. (D) Confocal images of infected (LI) and non-infected organoids (NI). Staining for NF-κB subunit p65 (red) indicates nuclear p65 in the infected organoid. (E) qPCR for IL-8 mRNA after injection of H. pylori or medium (mock). Bars represent average of duplicates with standard deviation. (F) Organoids were differentiated into gland-type organoids (with Wnt) or pit-type organoids (4 days Wnt withdrawal) and subsequently microinjected with H. pylori. After indicated time, mRNA was extracted and expression of IL-8 was measured with quantitative real time PCR. Bars represent average of duplicates with standard deviation. LI = Lumen infected organoid, NI = Noninfected organoid. Scale bar 200 nm (C) or 100 µm (B, E). * = Matrigel.