ABSTRACT
1. The role of probiotics in modulating intestinal mucosal immunity in chicks was investigated by measuring migration of intraepithelial lymphocytes (IEL) and cytokine signals in chicks fed on a diet supplemented with the Lactobacillus casei compared with those of chicks fed on an unsupplemented diet.
2. Increased numbers of intraepithelial lymphocytes (IEL) were detected in the ileal epithelium at d 3 and d 7 after feeding a diet containing 108 CFU/g L. casei.
3. Greater expression of chemokine genes for C-C motif chemokine ligand 3, C-X-C motif chemokine ligand 12, C-C motif chemokine receptor 5, and C-C motif chemokine receptor 9 were detected in the ileum on d 3, suggesting a greater number of IEL was associated with lymphocyte migration through the chemokine signalling pathway.
4. After IEL migration, cell proliferation was evident in mucosal epithelial cells on d 14. Evidence of immune responses induced in the ileum from d 3–21 after feeding the diet containing L. casei was shown by the significant (P < 0.05) differences in transforming growth factor-β, secretory immunoglobulin A, interferon-γ, tumour necrosis factor-α, interleukin-4, and interleukin-10.
5. These results indicated that feeding L. casei helps guide IEL migration and modulates intestinal mucosal immunity.
Disclosure statement
No potential conflict of interest was reported by the authors.