Establishing an Infection Model Through Microinjection of Gastric Organoids with Pathogenic Bacteria

Under a stereomicroscope, observe gastric organoids, three-dimensional cellular structures composed of differentiated gastric cells, and stem cells.

Introduce a microinjector loaded with Helicobacter pylori, a gastric pathogen.

Insert the needle into the target organoid and inject the bacterial suspension. 

Observe a cloudy solution develop within the lumen.

H.pylori employs a specific adhesin protein on its surface to bind to the gastric cell receptor, establishing a stable interaction between the bacteria and host cells.

This interaction triggers the elongation of the bacterial secretion pilus, a large tunnel-shaped structure that extends toward the host cell membrane.

H.pylori uses the secretion pilus to inject virulence factors, including cytotoxic associated gene A or CagA into the host cell.

Once inside the cell, CagA undergoes phosphorylation by the host cell kinase.

Phosphorylated CagA deregulates multiple intracellular signaling cascades that alter host cell functions, promoting cancerous transformation. 

Collect the infected organoids for further analysis.