title: Oral probiotic control skin inflammation by acting on both effector and regulatory T cells.
abstract: Probiotics are believed to alleviate allergic and inflammatory skin disorders, but their impact on pathogenic effector T cells remains poorly documented. Here we show that oral treatment with the probiotic bacteria L. casei (DN-114 001) alone alleviates antigen-specific skin inflammation mediated by either protein-specific CD4(+) T cells or hapten-specific CD8(+) T cells. In the model of CD8(+) T cell-mediated skin inflammation, which reproduces allergic contact dermatitis in human, inhibition of skin inflammation by L. casei is not due to impaired priming of hapten-specific IFNgamma-producing cytolytic CD8(+) effector T cells. Alternatively, L. casei treatment reduces the recruitment of CD8(+) effector T cells into the skin during the elicitation (i.e. symptomatic) phase of CHS. Inhibition of skin inflammation by L. casei requires MHC class II-restricted CD4(+) T cells but not CD1d-restricted NK-T cells. L casei treatment enhanced the frequency of FoxP3(+) Treg in the skin and increased the production of IL-10 by CD4(+)CD25(+) regulatory T cells in skin draining lymph nodes of hapten-sensitized mice. These data demonstrate that orally administered L. casei (DN-114 001) efficiently alleviate T cell-mediated skin inflammation without causing immune suppression, via mechanisms that include control of CD8(+) effector T cells and involve regulatory CD4(+) T cells. L. casei (DN-114 001) may thus represent a probiotic of potential interest for immunomodulation of T cell-mediated allergic skin diseases in human.
authors.affiliation: Université de Lyon, Lyon, France.
authors.forename: Feriel
authors.initials: F
authors.lastname: Hacini-Rachinel
authors.forename: Hanane
authors.initials: H
authors.lastname: Gheit
authors.forename: Jean-Benoit
authors.initials: JB
authors.lastname: Le Luduec
authors.forename: Fariel
authors.initials: F
authors.lastname: Dif
authors.forename: Stéphane
authors.initials: S
authors.lastname: Nancey
authors.forename: Dominique
authors.initials: D
authors.lastname: Kaiserlian
mesh_terms: D000284:Administration, Oral; D000818:Animals; D017690:Cell Transplantation; D002478:Cells, Cultured; D017449:Dermatitis, Allergic Contact / Q000188:drug therapy / Q000276:immunology; D005260:Female; D006801:Humans; D007249:Inflammation / Q000188:drug therapy / Q000276:immunology; D016753:Interleukin-10 / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D008826:Microbial Sensitivity Tests; D019936:Probiotics / Q000494:pharmacology / Q000627:therapeutic use; D012867:Skin / Q000166:cytology / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: D016753:Interleukin-10