title: Characterization of a novel maitake (Grifola frondosa) protein that activates natural killer and dendritic cells and enhances antitumor immunity in mice.
abstract: Grifola frondosa, also known as maitake, is a culinary mushroom with immune-enhancing and antitumor effects. Numerous studies have investigated the activity of maitake polysaccharide extracts, but studies of maitake proteins are scarce. In this study, we purified and characterized a new G. frondosa protein, GFP, from maitake fruiting bodies. GFP is a nonglucan heterodimeric 83 kDa protein that consists of two 41 kDa subunits. GFP induced interferon-γ secretion by murine splenocytes and natural killer cells and activated the maturation of bone marrow-derived dendritic cells (BMDCs) via a TLR4-dependent mechanism. GFP-treated BMDCs promoted a Th1 response and exhibited significant antitumor activity when transferred into tumor-bearing mice. In conclusion, we are the first to reveal the critical role of GFP in modulating the immune response and to link the immune-enhancing effects of maitake to its antitumor activities.
authors.affiliation: Department of Horticulture, National Taiwan University , Taipei 10673, Taiwan.
authors.forename: Yao-Wei
authors.initials: YW
authors.lastname: Tsao
authors.forename: Yen-Chou
authors.initials: YC
authors.lastname: Kuan
authors.forename: Jia-Lin
authors.initials: JL
authors.lastname: Wang
authors.forename: Fuu
authors.initials: F
authors.lastname: Sheu
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D003713:Dendritic Cells / Q000187:drug effects / Q000276:immunology*; D048690:Fruiting Bodies, Fungal / Q000737:chemistry; D005656:Fungal Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D048691:Grifola / Q000737:chemistry*; D006801:Humans; D007109:Immunity / Q000187:drug effects; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology*; D008213:Lymphocyte Activation / Q000187:drug effects; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D009369:Neoplasms / Q000188:drug therapy* / Q000276:immunology*
chemical_list: D005656:Fungal Proteins