title: Merozoite surface protein-1 of Plasmodium yoelii fused via an oligosaccharide moiety of cholera toxin B subunit glycoprotein expressed in yeast induced protective immunity against lethal malaria infection in mice.
abstract: Methylotrophic yeast (Pichia pastoris) secreted cholera toxin B subunit (CTB) predominantly as a biologically active pentamer (PpCTB) with identical ganglioside binding affinity profiles to that of choleragenoid. Unlike choleragenoid, however, the PpCTB did not induce a footpad edema response in mice. Of the two potential glycosylation sites (NIT(4-6) and NKT(90-92)) for this protein, a N-linked oligosaccharide was identified at Asn4. The oligosaccharide, presumed to extend from the lateral circumference of the CTB pentamer ring structure, was exploited as a site-specific anchoring scaffold for the C-terminal 19-kDa merozoite surface protein-1 (MSP1-19) of the rodent malaria parasite, Plasmodium yoelii. Conjugation of MSP1-19 to PpCTB via its oligosaccharide moiety induced higher protective efficacy against lethal parasite infection than conjugation directly to the PpCTB protein body in both intranasal and subcutaneous immunization regimes. Such increased protection was potentially due to the higher antigen loading capacity of CTB achieved when the antigen was linked to the extended branches of the oligosaccharide. This might have allowed the antigen to reside in more spacious molecular environment with less steric hindrance between the constituent molecules of the fusion complex.
authors: Molecular Microbiology Group, Department of Tropical Infectious Diseases, COMB, Tropical Biosphere Research Center, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan.
authors: Takeshi
authors: T
authors: Miyata
authors: Tetsuya
authors: T
authors: Harakuni
authors: Toki
authors: T
authors: Taira
authors: Goro
authors: G
authors: Matsuzaki
authors: Takeshi
authors: T
authors: Arakawa
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D002772:Cholera Toxin / Q000235:genetics / Q000276:immunology*; D004195:Disease Models, Animal; D005260:Female; D006023:Glycoproteins / Q000235:genetics / Q000276:immunology*; D007279:Injections, Subcutaneous; D008288:Malaria / Q000276:immunology / Q000517:prevention & control*; D017780:Malaria Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D020066:Merozoite Surface Protein 1 / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D010843:Pichia / Q000235:genetics / Q000378:metabolism; D010967:Plasmodium yoelii / Q000235:genetics / Q000276:immunology*; D016019:Survival Analysis; D018074:Vaccines, Conjugate / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology
chemical_list: D006023:Glycoproteins; D017780:Malaria Vaccines; D020066:Merozoite Surface Protein 1; D018074:Vaccines, Conjugate; D014614:Vaccines, Synthetic; D002772:Cholera Toxin