Fluoview scanning confocal microscope

Gastric samples were embedded in paraffin and sliced into 5‐μm‐thick sections. Paraffin blocks were sectioned and stained with hematoxylin and eosin (H&E) for histopathological evaluation. The polymorphonuclear and mononuclear cells in the gastric antrum and in vivo were graded as follows (Ten Kate et al., 2009): 0 represents none; 1 represents some infiltration; 2 represents mild infiltration (indicating that there are very few aggregates in the submucosa and mucosa); 3 represents moderate infiltration (indicating that there are several aggregates in the submucosa and mucosa); 4 represents marked infiltration (indicating that there are many large aggregates in the submucosa and mucosa); 5 represents dense infiltration of almost the entire mucosa; and 6 represents dense infiltration of the entire mucosa. Paraffin‐embedded stomach tissue sections were immunostained with a cystathionine‐γ‐lyase (CSE) antibody (Proteintech Group, Inc.), followed by labeling with an Alexa Fluor‐conjugated secondary antibody (ZSGB‐BIO Ltd.). We used species‐matched immunoglobulins as controls for every antibody. Finally, an Olympus FluoView scanning confocal microscope (Olympus) was used to generate the immunofluorescence (IF) images.