Fig. 8: Chicken enteroids as a model for host–bacterial interactions.

a–f Representative z-axis projections of chicken enteroids 2 days in culture whole-mount stained to detect cell nuclei (DAPI, blue) and F-actin-expressing brush border (red). Enteroids incubated with a–c wild type S. Typhimurium-GFP (green) and d–f mutant non-invasive S.Typimurium-GFP (green) at 4 h. Magnified images of a1 actin remodelling, b1 intracellular bacteria and d1, f1 lack of actin remodelling and intracellular bacteria. Images are representative of data from at least 3 independent cultures each containing 2–3 embryos. Scale bar: 20 µm. g Bacterial net replication assay confirmed Salmonella counts were significantly increased for enteroids infected with wild-type versus mutant Salmonella strains. Box and whisker plot represent bacterial count from ~800 infected enteroids post high-dose gentamicin treatment. Data derived from 5 independent experiments with 2–3 embryos per culture. ***p < 0.0002, W = 55, 95.5% CI for n1–n2 is (−419850, −189760) using a Mann–Whitney U-test (two-sided). The assay also showed wild-type Salmonella replicated in the enteroids over 0–8 h. ***p < 0.0001, R² = 0.73, df = 29 using a linear regression test.