title: Combination of a TLR4 ligand and anaphylatoxin C5a for the induction of antigen-specific cytotoxic T cell responses.
abstract: The complement system and Toll-like receptors (TLR) are key innate defense systems which might interact synergistically on dendritic cells (DC) to reinforce adaptive immunity. In a previous work, we found that the extra domain A from fibronectin EDA (an endogenous ligand for TLR4) can favour antigen delivery to DC and induce their maturation. Given the potential of anaphylatoxins to cause inflammation and activation of myeloid cells, we hypothesized that a fusion protein between EDA, and anaphylatoxins C3a, C4a or C5a together with an antigen might improve the immunogenicity of the antigen. Naked DNA immunization with a construct expressing the fusion protein between C5a, EDA and the cytotoxic T cell epitope SIINFEKL from ovalbumin, induced strong antigen specific T cell responses. The purified recombinant fusion protein EDA-SIINFEKL-C5a induced activation of dendritic cells, the production of proinflammatory cytokines/chemokines and stimulated antigen presenting cell migration and NK cell activation. As compared to EDA-SIINFEKL, the fusion protein EDA-SIINFEKL-C5a did not induce the production of the immunosuppressive molecules IL-10, CCL17, CCL1, CXCL12 or XCL1 by DC. Moreover, EDA-SIINFEKL-C5a induced strong specific T cell responses in vivo and protected mice against E.G7-OVA tumor growth more efficiently than EDA-SIINFEKL or SIINFEKL-C5a recombinant proteins. Our results suggest that fusion proteins containing EDA, the anaphylatoxin C5a and the antigen may serve as a suitable strategy for the development of anti-tumor or anti-viral vaccines.
authors.affiliation: Gene Therapy and Hepatology Area and Oncology Area, Center for Applied Medical Research, University of Navarra, 31008 Pamplona, Spain.
authors.forename: Francesc
authors.initials: F
authors.lastname: Rudilla
authors.forename: Catherine
authors.initials: C
authors.lastname: Fayolle
authors.forename: Noelia
authors.initials: N
authors.lastname: Casares
authors.forename: Maika
authors.initials: M
authors.lastname: Durantez
authors.forename: Laura
authors.initials: L
authors.lastname: Arribillaga
authors.forename: Teresa
authors.initials: T
authors.lastname: Lozano
authors.forename: Lorea
authors.initials: L
authors.lastname: Villanueva
authors.forename: Ruben
authors.initials: R
authors.lastname: Pio
authors.forename: Pablo
authors.initials: P
authors.lastname: Sarobe
authors.forename: Claude
authors.initials: C
authors.lastname: Leclerc
authors.forename: Jesús
authors.initials: J
authors.lastname: Prieto
authors.forename: Juan José
authors.initials: JJ
authors.lastname: Lasarte
mesh_terms: D000706:Anaphylatoxins / Q000235:genetics / Q000276:immunology*; D000818:Animals; D019496:Cancer Vaccines / Q000008:administration & dosage / Q000276:immunology; D015936:Complement C5a / Q000235:genetics / Q000276:immunology*; D016207:Cytokines / Q000378:metabolism; D053331:Ectodysplasins / Q000235:genetics / Q000276:immunology*; D018984:Epitopes, T-Lymphocyte / Q000235:genetics / Q000276:immunology; D005260:Female; D051379:Mice; D008810:Mice, Inbred C57BL; D009369:Neoplasms / Q000276:immunology / Q000517:prevention & control; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D051197:Toll-Like Receptor 4 / Q000819:agonists*; D019444:Vaccines, DNA / Q000008:administration & dosage / Q000276:immunology
chemical_list: D000706:Anaphylatoxins; D019496:Cancer Vaccines; D016207:Cytokines; D053331:Ectodysplasins; C506019:Eda protein, mouse; D018984:Epitopes, T-Lymphocyte; D011993:Recombinant Fusion Proteins; C493487:Tlr4 protein, mouse; D051197:Toll-Like Receptor 4; D019444:Vaccines, DNA; D015936:Complement C5a