title: Mgn-3/biobran enhances generation of cytotoxic CD8+ T cells via upregulation of dec-205 expression on dendritic cells.
abstract: Arabinoxylan rice bran (MGN-3/Biobran) has been shown to be a potent biological response modifier (BRM) that activates different arms of the immune system, including dendritic cells (DCs), which prime CD4+ helper T-cell responses. The present study explores the ability of MGN-3-activated DCs to prime CD8+ T cells and examines the mechanisms underlying its effect. Human monocyte-derived DCs were treated with MGN-3 (20 and 40 &#956;g/ml). Results indicate that treatment with MGN-3 caused DCs to prime higher granzyme B-expressing CD8+ T cells. Tumor lysate-pulsed MGN-3 DC also increased tumor cell killing compared to DC-stimulated CD8+ T cells. This was associated with: i) increased expression of DEC-205 in MGN-3-activated DCs in a dose-dependent manner; and ii) MGN-3 induced significant production of Type III interferon, IL29, but not Type I IFNs &#945; and &#946;. These results suggest that MGN-3 is a potent natural adjuvant that efficiently activates DCs and may therefore be useful for mounting an efficient immune response against infections and cancer.
authors.affiliation: Charles Drew University of Medicine and Science, Los Angeles, CA, U.S.A.
authors.forename: M
authors.initials: M
authors.lastname: Ghoneum
authors.affiliation: Division of Basic and Clinical Immunology, University of California, Irvine, CA, U.S.A.
authors.forename: S
authors.initials: S
authors.lastname: Agrawal
mesh_terms: D015703:Antigens, CD / Q000502:physiology*; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000276:immunology*; D006801:Humans; D007372:Interferons / Q000378:metabolism; D037181:Lectins, C-Type / Q000502:physiology*; D015778:Minor Histocompatibility Antigens; D011956:Receptors, Cell Surface / Q000502:physiology*; D015854:Up-Regulation; D014990:Xylans / Q000494:pharmacology*
chemical_list: D015703:Antigens, CD; C093569:DEC-205 receptor; D037181:Lectins, C-Type; D015778:Minor Histocompatibility Antigens; D011956:Receptors, Cell Surface; D014990:Xylans; C419427:polysaccharide MGN3; D007372:Interferons