Commensal-Induced Regulatory T Cells Mediate Protection against Pathogen-Stimulated NF-κB Activation

• DOI: 10.1371/journal.ppat.1000112
• Publication Date: 2008-07-31T22:29:49Z
• Authors: Caitlin O'Mahony; Paul Scully; David O'Mahony; Sharon Murphy; Frances O'Brien; Anne Lyons; Graham Sherlock; John MacSharry; Barry Kiely; Fergus Shanahan; Liam O'Mahony
• Keywords: Adoptive Cell Transfer; Regulatory T cell; Regulatory B cells; Innate lymphoid cell

Host defence against infection requires a range of innate and adaptive immune responses that may lead to tissue damage. Such immune-mediated pathologies can be controlled with appropriate T regulatory (Treg) activity. The aim the present study was determine influence gut microbiota composition on Treg cellular activity NF-κB activation associated infection. Mice consumed commensal microbe Bifidobacterium infantis 35624 followed by Salmonella typhimurium or injection LPS. In vivo quantified using biophotonic imaging. CD4+CD25+Foxp3+ cell phenotypes cytokine levels were assessed flow cytometry while CD4+ cells isolated magnetic beads for adoptive transfer naïve animals. imaging revealed profound inhibition LPS induced preceded reduction in S. numbers murine sickness behaviour scores B. infantis–fed mice. addition, pro-inflammatory secretion, proliferation, dendritic co-stimulatory molecule expression significantly reduced. contrast, increased mucosa spleen mice fed infantis. Adoptive CD4+CD25+ transferred inhibitory Consumption single micro-organism drives generation function which control excessive vivo. These interactions provide basis more complete understanding commensal-host-pathogen trilogue contribute host homeostatic mechanisms underpinning protection aberrant system response translocating pathogen systemic