title: New method for obtaining conjugated vaccines.
abstract: We describe a new method to obtain conjugates against Neisseria meningitidis serogroups A, B, C, Vibrio cholera, and Salmonella typhi and their immunogenicity in Balb/c mice. The saccharides were activated by basic hydrolysis with the generation of amine groups in the saccharidic chain, and these groups were linked to carboxyl groups of tetanus toxoid by via carbodiimida-mediated reaction. The resultant conjugates were administered to mice for the immunogenicity studies. The pirogenicity of LPS was measured by LAL assay. The anti-saccharide IgG, IgG1, and IgG2a antibodies were evaluated. A significant decrease in the pirogenicity of LPS after basic hydrolysis treatment was observed. The conjugates elicited higher titers of anti-polysaccharides or anti-LPS IgG, IgG1, and IgG2a in conjugates than in unconjugated saccharides. The results indicate that we have a new method for obtaining conjugated vaccines and we have demonstrated that after conjugation there was a change in the responses for all saccharides, from thymus-independent to thymus-dependent responses.
authors.affiliation: Immunology Department, Finlay Institute, Ave. 27 No. 19805, P.O. Box 16017, Havana, Cuba. ocabrera@finlay.edu.cu
authors.forename: Osmir
authors.initials: O
authors.lastname: Cabrera
authors.forename: Maribel
authors.initials: M
authors.lastname: Cuello
authors.forename: Carmen R
authors.initials: CR
authors.lastname: Soto
authors.forename: Miguel E
authors.initials: ME
authors.lastname: Martínez
authors.forename: Judith M
authors.initials: JM
authors.lastname: del Campo
authors.forename: Oliver a
authors.initials: Oa
authors.lastname: Pérez
authors.forename: Juan F
authors.initials: JF
authors.lastname: Infante
authors.forename: Gustavo
authors.initials: G
authors.lastname: Sierra
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D008070:Lipopolysaccharides / Q000737:chemistry* / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D009345:Neisseria meningitidis / Q000737:chemistry / Q000276:immunology; D012485:Salmonella typhi / Q000737:chemistry / Q000276:immunology; D013745:Tetanus Toxoid / Q000737:chemistry* / Q000276:immunology; D018074:Vaccines, Conjugate / Q000737:chemistry* / Q000302:isolation & purification; D014734:Vibrio cholerae / Q000737:chemistry / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D008070:Lipopolysaccharides; D013745:Tetanus Toxoid; D018074:Vaccines, Conjugate