title: Modulation of Th1/Th2 immune responses by killed Propionibacterium acnes and its soluble polysaccharide fraction in a type I hypersensitivity murine model: induction of different activation status of antigen-presenting cells.
abstract: Propionibacterium acnes (P. acnes) is a gram-positive anaerobic bacillus present in normal human skin microbiota, which exerts important immunomodulatory effects, when used as heat- or phenol-killed suspensions. We previously demonstrated that heat-killed P. acnes or its soluble polysaccharide (PS), extracted from the bacterium cell wall, suppressed or potentiated the Th2 response to ovalbumin (OVA) in an immediate hypersensitivity model, depending on the treatment protocol. Herein, we investigated the mechanisms responsible for these effects, using the same model and focusing on the activation status of antigen-presenting cells (APCs). We verified that higher numbers of APCs expressing costimulatory molecules and higher expression levels of these molecules are probably related to potentiation of the Th2 response to OVA induced by P. acnes or PS, while higher expression of toll-like receptors (TLRs) seems to be related to Th2 suppression. In vitro cytokines production in cocultures of dendritic cells and T lymphocytes indicated that P. acnes and PS seem to perform their effects by acting directly on APCs. Our data suggest that P. acnes and PS directly act on APCs, modulating the expression of costimulatory molecules and TLRs, and these differently activated APCs drive distinct T helper patterns to OVA in our model.
authors.affiliation: Laboratório de Imunoquímica, Instituto Butantan, Avenida Vital Brazil 1500, Prédio Novo, 2° Andar, Butantã, 05503-900 São Paulo, SP, Brazil.
authors.forename: Carla Cristina
authors.identifier: 0000-0002-4187-798X
authors.initials: CC
authors.lastname: Squaiella-Baptistão
authors.affiliation: Disciplina de Imunologia, Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, Rua Botucatu 862, Edifício de Ciências Biomédicas, 4° Andar, Vila Clementino, 04023-062 São Paulo, SP, Brazil.
authors.forename: Daniela
authors.identifier: 0000-0001-7092-2009
authors.initials: D
authors.lastname: Teixeira
authors.affiliation: Disciplina de Imunologia, Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, Rua Botucatu 862, Edifício de Ciências Biomédicas, 4° Andar, Vila Clementino, 04023-062 São Paulo, SP, Brazil.
authors.forename: Juliana Sekeres
authors.initials: JS
authors.lastname: Mussalem
authors.affiliation: Disciplina de Imunologia, Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, Rua Botucatu 862, Edifício de Ciências Biomédicas, 4° Andar, Vila Clementino, 04023-062 São Paulo, SP, Brazil.
authors.forename: Mayari Eika
authors.initials: ME
authors.lastname: Ishimura
authors.affiliation: Disciplina de Imunologia, Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, Rua Botucatu 862, Edifício de Ciências Biomédicas, 4° Andar, Vila Clementino, 04023-062 São Paulo, SP, Brazil.
authors.forename: Ieda Maria
authors.initials: IM
authors.lastname: Longo-Maugéri
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology; D018122:B7-1 Antigen / Q000096:biosynthesis; D051940:B7-2 Antigen / Q000096:biosynthesis; D019013:CD40 Antigens / Q000096:biosynthesis; D016207:Cytokines / Q000276:immunology; D004195:Disease Models, Animal; D005260:Female; D006969:Hypersensitivity, Immediate / Q000276:immunology*; D008213:Lymphocyte Activation / Q000276:immunology; D051218:Lymphocyte Antigen 96 / Q000276:immunology; D008264:Macrophages / Q000276:immunology; D008297:Male; D051379:Mice; D008805:Mice, Inbred A; D008807:Mice, Inbred BALB C; D053594:Myeloid Differentiation Factor 88 / Q000276:immunology; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D011425:Propionibacterium acnes / Q000276:immunology*; D018417:Th1 Cells / Q000276:immunology*; D018418:Th2 Cells / Q000276:immunology*; D051195:Toll-Like Receptor 2 / Q000096:biosynthesis / Q000276:immunology; D051197:Toll-Like Receptor 4 / Q000096:biosynthesis / Q000276:immunology
chemical_list: D018122:B7-1 Antigen; D051940:B7-2 Antigen; D019013:CD40 Antigens; D016207:Cytokines; C411728:Ly96 protein, mouse; D051218:Lymphocyte Antigen 96; C507780:Myd88 protein, mouse; D053594:Myeloid Differentiation Factor 88; D011135:Polysaccharides, Bacterial; C493486:Tlr2 protein, mouse; C493487:Tlr4 protein, mouse; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4