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.

摘要

1. 通过测量饲喂干酪乳杆菌日粮的雏鸡与饲喂未添加干酪乳杆菌的雏鸡的上皮内淋巴细胞 (IEL) 迁移和细胞因子信号，研究了益生菌在调节雏鸡肠粘膜免疫中的作用。

2. 在喂食含有 10 ⁸ CFU/g L. casei的饮食后，在第 3 天和第 7 天回肠上皮中检测到上皮内淋巴细胞 (IEL) 数量增加。

3. 在第 3 天在回肠中检测到 CC 基序趋化因子配体 3、CXC 基序趋化因子配体 12、CC 基序趋化因子受体 5 和 CC 基序趋化因子受体 9 的趋化因子基因的更多表达，表明更多的 IEL 与淋巴细胞通过趋化因子信号通路迁移。

4. IEL 迁移后，第 14 天粘膜上皮细胞中细胞增殖明显。在喂食含有干酪乳杆菌的饮食后，第 3-21 天回肠中诱导的免疫反应的证据显示为显着（P < 0.05）差异在转化生长因子-β、分泌性免疫球蛋白 A、干扰素-γ、肿瘤坏死因子-α、白细胞介素-4 和白细胞介素-10 中。

5. 这些结果表明，饲喂干酪乳杆菌有助于引导 IEL 迁移并调节肠粘膜免疫。