The effect of immunoregulatory bacteria on the transcriptional activity of Foxp3 and RORyt genes in the gut-associated lymphoid tissue with -induced inflammation in the presence of vancomycin and .

BACKGROUND AND OBJECTIVES

Intestinal microbiota is involved in the development and maintenance of immune homeostasis. This study was conducted to investigate the levels of key immunoregulatory bacteria in the intestinal wall-associated microflora and its effect on the transcriptional activity of the Foxp3 and RORyt genes in the gut-associated lymphoid tissue (GALT) of rats with -induced inflammation, both untreated and treated with vancomycin and .

MATERIALS AND METHODS

To determine the levels of immunoregulatory bacteria in GALT of rats Q-PCR was used to identify them by species-specific 16S rDNA genes. Transcriptional activity of Foxp3 and RORyt genes was determined using Q-PCR with reverse transcription.

RESULTS

In animals treated with both vancomycin and , the levels of segmented filamentous bacteria (SFB) increased while and decreased. In rats that received pretreatment with vancomycin and then were infected with Enteritidis and Typhimurium, the levels of increased, and the number of group, spp. clusters XIV, IV, and significantly decreased, decreasing Foxp3 and increasing Rorγt mRNA expression. Administration of to animals treated with Enteritidis or Typhimurium and pre-treated with vancomycin caused a decrease in and Rorγt mRNA levels and conversely, increased the numbers of the group, spp. clusters XIV, IV, and Foxp3 gene expression in GALT.

CONCLUSION

Our results suggest that the commensal microorganism may provide a protective role against the development of experimental colitis, which has to be taken into consideration for further clarification of the effective therapeutic strategy of inflammatory bowel diseases, irritable bowel syndrome and necrotising colitis.