Induction of cytokine formation by human intestinal bacteria in gut epithelial cell lines

B. Bahrami, S. Macfarlane, G. T. Macfarlane

    Research output: Contribution to journalArticle

    63 Citations (Scopus)

    Abstract

    Aims:

    To investigate the effects of human gut micro-organisms on cytokine production by human intestinal cell lines.

    Methods and Results:

    Quantitative real-time PCR assays were developed to measure the production of pro-inflammatory (IL-1 alpha, IL-6, IL-18 and TNF alpha) and anti-inflammatory (TGF-beta 1, TGF-beta 2, TGF-beta 3, IL-4 and IL-10) cytokines in HT-29 and Caco-2 cell lines. They were co-cultured with a range of mucosal bacteria isolated from ulcerative colitis patients, together with lactobacilli and bifidobacteria obtained from healthy people. HT-29 cells were also co-cultured with Campylobacter jejuni, enterotoxigenic Escherichia coli (ETEC), enteropathogenic E. coli and Salmonella typhimurium. The majority of commensal bacteria tested suppressed the expression of anti-inflammatory cytokine mRNA, increased IL-18, reduced IL-1 alpha, and with the exception of nonpathogenic E. coli, reduced TNF-alpha. All overtly pathogenic species increased both pro-inflammatory and anti-inflammatory cytokine mRNA.

    Conclusion:

    Commensal and pathogenic species induced fundamentally different cytokine responses in human intestinal epithelial cell lines.

    Significance and Impact of the Study:

    Interactions between commensal bacteria tested in this study and the innate immune system were shown to be anti-inflammatory in nature, in contrast to the pathogenic organisms investigated. These data contribute towards our understanding of how potential probiotic species can be used to suppress the pro-inflammatory response in inflammatory bowel disease.

    Original languageEnglish
    Pages (from-to)353-363
    Number of pages11
    JournalJournal of General and Applied Microbiology
    Volume110
    Issue number1
    Early online date10 Nov 2010
    DOIs
    Publication statusPublished - Jan 2011

    Keywords

    • Bifidobacteria
    • Commensal bacteria
    • Cytokine expression
    • Lactobacilli
    • Pathogenic bacteria
    • Real-time quantitative PCR
    • Inflammatory bowel disease
    • Enteropathogenic escherichia coli
    • Real time PCR
    • NF-KAPPA-B
    • Ulcerative colitis
    • Glyceraldehyde-3-phosphate dehydrogenase (GAPDH)
    • Dendritic cells
    • Crohns disease
    • Beta defensin
    • Expression

    Cite this