Effect of Lactobacillus Rhamnosus GG on the Number and Differentiation of T Lymphocytes in the Intestine of Early Weaned Piglets

Background: Probiotics are defined as living microorganisms by the United Nations (FAO) and the World Health Organization (WHO). When appropriate quantities are used, probiotics will have beneficial effects on human and animal bodies. Probiotics can be used to prevent and treat intestinal infection, urogenital diseases, bacterial vaginosis and skin diseases. Methods: In this study, Lactobacillus rhamnosus GG (LGG) ATCC53103 was selected as the experimental strain. Sixty-five-day healthy piglets were randomly divided into two groups, the experimental group LGG group and the control group PBS group. The piglets in LGG group were given 1 ml LGG (6 × 109 cfu/ml) every day. The piglets in the PBS group were given 1 ml PBS every day. Piglets were slaughtered on the 15th day, and the mesenteric lymph nodes (MLN), ileum and Peyer’s patches (PPs), ileum and jejunal lamina propria (LP) were taken. The expression of CD3+ CD4+ T lymphocytes and CD4+ CD8+ double positive T lymphocytes were detected by flow cytometry and immunefluorescence. Resutlts: The results of flow cytometry showed that there was no significant difference in CD3+ CD4+ T lymphocytes in the MLN of the LGG group compared with the PBS group (P > 0.05). The CD3+ CD4+ T lymphocytes in the jejunum and ileum of the LGG group were significantly different from those in the PBS group (P < 0.05) (P < 0.05). The CD3+ CD4+ T lymphocytes in the jejunum LP of piglets in LGG group were significantly different from those in PBS group (P < 0.05). In the LGG group, CD3+ CD4+ T lymphocytes in the ileal LP of piglets were significantly different from those in the PBS group (P < 0.01). The CD4+ CD8+ T lymphocytes in the IEL of the LGG group were significantly higher than those in the PBS group (P < 0.001). Conclusion: In summary, LGG can stimulate the increase in the number of T lymphocytes in piglets and tend to differentiate into Th1.