title: Hydrophobic moeties in recombinant proteins are crucial to generate efficient saponin-based vaccine against Apicomplexan Babesia divergens.
abstract: Throughout Europe, bovine babesiosis is mainly caused by Babesia divergens, an Apicomplexan parasite transmitted by tick bites. The intra-erythrocytic development of B. divergens merozoites leads to haemolytic anaemia, and bovine babesiosis is responsible for economic losses in the agro-business industry. A totally efficient recombinant vaccine based on the merozoite surface protein Bd37 and saponin QuilA was recently described. In the present study we determined that protective immunity elicited by the Bd37 recombinant protein was related to the presence of hydrophobic residues in the protein. Using polymeric fusion of Bd37 as well as cell-free in vitro protein expression, we successfully expressed recombinant proteins containing hydrophobic sequences without the need of GST fusion. We used different hydrophobic sequences and different recombinant Bd37 proteins to demonstrate that antigen hydrophobicity affects the immune system, turning an inefficient protein into a 100% protective vaccine. Some hypotheses about the hydrophobic effect and its potential application to other parasitic protozoa vaccine are also discussed.
authors.affiliation: Laboratoire de Biologie Cellulaire et Moleculaire, ERT 1038 Vaccination anti-parasitaire, Faculté de Pharmacie, 15 Avenue Charles Flahault, BP 14 491, 34093 Montpellier cedex 05, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Delbecq
authors.forename: Kamel
authors.initials: K
authors.lastname: Hadj-Kaddour
authors.forename: Sylvie
authors.initials: S
authors.lastname: Randazzo
authors.forename: Jos
authors.initials: J
authors.lastname: Kleuskens
authors.forename: Theo
authors.initials: T
authors.lastname: Schetters
authors.forename: André
authors.initials: A
authors.lastname: Gorenflot
authors.forename: Eric
authors.initials: E
authors.lastname: Précigout
mesh_terms: D000818:Animals; D001403:Babesia / Q000276:immunology*; D001404:Babesiosis / Q000276:immunology* / Q000662:veterinary*; D001428:Bacterial Vaccines / Q000276:immunology*; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D018604:Epitope Mapping; D004926:Escherichia coli / Q000378:metabolism; D005260:Female; D005849:Gerbillinae; D016052:Protozoan Vaccines / Q000096:biosynthesis / Q000737:chemistry / Q000276:immunology*; D012503:Saponins / Q000276:immunology*; D014614:Vaccines, Synthetic / Q000096:biosynthesis / Q000737:chemistry / Q000276:immunology
chemical_list: D001428:Bacterial Vaccines; D016052:Protozoan Vaccines; D012503:Saponins; D014614:Vaccines, Synthetic