Bifidobacterium infantis Induces Protective Colonic PD-L1 and Foxp3 Regulatory T Cells in an Acute Murine Experimental Model of Inflammatory Bowel Disease
- 2019-04-17
- Gut and Liver 13(4)
- Linyan Zhou
- Dongyan Liu
- Ying Xie
- Xinjie Yao
- Yan Li
- PubMed: 30600673
- DOI: 10.5009/gnl18316
Abstract
Background/aims: The current study aims to investigate the protective effects of Bifidobacterium infantis on the abnormal immune response to inflammatory bowel disease (IBD) in dextran sodium sulfate (DSS)-induced colitis.
Methods: Eight-week-old BALB/c mice were separated into five groups at random (control, DSS, DSS+B9 [B. infantis 1×109 CFU], DSS+B8 [B. infantis 1×108 CFU], and DSS+B7 [B. infantis 1×107 CFU]). Colitis was induced by 5% DSS ad libitum for 7 days, at which time we assessed weight, the disease activity index (DAI) score, and the histological damage score. The nuclear transcription factor Foxp3 (a marker of Treg cells), cytokines interleukin-10 (IL-10) and transforming growth factor β1 (TGF-β1), and related proteins (programmed cell death ligand 1 [PD-L1] and programmed cell death 1 [PD-1]) were detected by an immunohistochemical method and Western blot.
Results: B. infantis increased weight, decreased DAI scores and histological damage scores, increased the protein expression of Foxp3 (p<0.05) and cytokines IL-10 and TGF-β1 in mouse colon tissue (p<0.05), and increased the expression of PD-L1 in the treatment groups relative to that in the DSS group (p<0.05). The effect of B. infantis on Foxp3 and PD-L1 was dose dependent in the treatment groups (p<0.05). PD-L1 was positively correlated with Foxp3, IL-10, and TGF-β1.
Conclusions: In a mouse model of IBD, B. infantis can alleviate intestinal epithelial injury and maintain intestinal immune tolerance and thus may have potential therapeutic value for the treatment of immune damage in IBD.
Keywords: Bifidobacterium infantis; Inflammatory bowel disease; Programmed cell death ligand 1; T-Lymphocytes; regulatory.
Research Insights
| Supplement | Health Outcome | Effect Type | Effect Size |
|---|---|---|---|
| Bifidobacterium infantis | Enhanced Foxp3 Expression | Beneficial | Moderate |
| Bifidobacterium infantis | Increased PD-L1 Expression | Beneficial | Moderate |
| Bifidobacterium infantis | Maintained Intestinal Immune Tolerance | Beneficial | Large |
| Bifidobacterium infantis | Reduced Colitis Symptoms | Beneficial | Moderate |
| Bifidobacterium infantis BI02 | Improved Intestinal Epithelial Intercellular Integrity | Beneficial | Large |
| Bifidobacterium infantis BI02 | Increased Body Weight | Beneficial | Moderate |
| Bifidobacterium infantis BI02 | Increased Foxp3 Protein Levels | Beneficial | Moderate |
| Bifidobacterium infantis BI02 | Increased PD-L1 Expression | Beneficial | Moderate |
| Bifidobacterium infantis BI02 | Reduced Disease Activity Index Scores | Beneficial | Moderate |
| Bifidobacterium infantis BI02 | Reduced Histological Damage Scores | Beneficial | Moderate |
| Bifidobacterium infantis MAK22B04I | Improved Intestinal Epithelial Intercellular Integrity | Beneficial | Large |
| Bifidobacterium infantis MAK22B04I | Increased Foxp3 Protein Expression | Beneficial | Moderate |
| Bifidobacterium infantis MAK22B04I | Increased IL-10 Levels | Beneficial | Moderate |
| Bifidobacterium infantis MAK22B04I | Increased PD-L1 Expression | Beneficial | Moderate |