Impact of Lactic Acid Bacteria on Dendritic Cells from Allergic Patients in an Experimental Model of Intestinal Epithelium
C´ eline Ratajczak,1, 2, 3 Catherine Duez,1, 2, 3 Corinne Grangette,4 Pierre Pochard,1, 2, 3, 5 Andr ´e-Bernard Tonnel,1, 2, 3 and Jo¨ el Pestel1, 2, 3
1Institut National de la Sant´e et de la RechercheM´edicale (INSERM) U 416, Institut F´ed´eratif de Recherche 17 (IFR 17), Institut Pasteur de Lille, 59019 Lille, France
2Institut Pasteur de Lille, 59019 Lille, France
3Universit´e de Lille 2, 59800 Lille, France
4Bact´eries Lactiques et Immunit´e des Muqueuses, Institut Pasteur de Lille, 59019 Lille, France
5The Department of Immunology, Faculty of Medicine, University of Manitoba, Basic Medical Sciences Building, Winnipeg, MB, Canada R3E 0W3
Lactic acid bacteria (LAB) are Gram positive nonpathogenic commensal organisms present in human gastrointestinal tract. In vivo, LAB are separated from antigen-presenting cells such as dendritic cells (DC) by the intestinal epithelial barrier. In this study, the impact of one LAB strain (Lactobacillus casei ATCC393) on human monocyte-derived DC from allergic and healthy donors was assessed by using a polarized epithelium model. Confocal and flow cytometer analyses showed that immature DC efficiently captured FITC-labelled L. casei through the epithelial layer. After interaction with L. casei, DC acquired a partial maturation status (i.e., CD86 and CD54 increase) and increased their interleukin (IL)-10 and IL-12 production. Interestingly, after activation by L. casei in the presence of experimental epithelium, DC from allergic patients instructed autologous na¨ıve CD4+ T cells to produce more interferon-γ than without the epithelium. Thus by modulating human DC reactivity, LAB and intestinal epithelium might modify T cell immune response and regulate the development of allergic reaction.
Journal of Biomedicine and Biotechnology, Volume 2007, Article ID 71921, 9 pages. This is an open access article distributed under the Creative Commons Attribution License.