Production and characterization of murine monoclonal antibodies against Haemophilus parasuis and study of their protective role in mice

• Published in: Microbiology (Society for General Microbiology) Vol. 150; no. 12; pp. 3935 - 3945
• Main Authors: Tadjine, M, Mittal, K. R, Bourdon, S, Gottschalk, M
• Format: Journal Article
• Language: English
• Published: Reading Soc General Microbiol 01.12.2004; Society for General Microbiology
• Subjects: Amino Acid Sequence; Animals; Antibodies, Bacterial - biosynthesis; Antibodies, Bacterial - blood; Antibodies, Bacterial - immunology; Antibodies, Monoclonal - biosynthesis; Antibodies, Monoclonal - blood; Antibodies, Monoclonal - immunology; Antigens, Bacterial - immunology; Applied microbiology; Bacterial Outer Membrane Proteins - chemistry; Bacterial Outer Membrane Proteins - immunology; Bacteriology; Biological and medical sciences; Epitopes - immunology; Fundamental and applied biological sciences. Psychology; Haemophilus Infections - immunology; Haemophilus Infections - prevention & control; Haemophilus parasuis; Haemophilus parasuis - immunology; Hybridomas; Immunization; Immunodeficiencies. Immunoglobulinopathies; Immunoglobulinopathies; Immunopathology; Lipopolysaccharides - immunology; Medical sciences; Mice; Mice, Inbred BALB C; Microbiology; Miscellaneous; Molecular Sequence Data; Rabbits; Species Specificity; Vaccines, antisera, therapeutical immunoglobulins and monoclonal antibodies (general aspects); Spleen; Immunopathology; Immunization; Antigenic determinant; Haemophilus; Reference; Rodentia; Malignant hemopathy; Monoclonal antibody; Myeloma; Cell surface; Strain; Pasteurellaceae; Vertebrata; Mammalia; Treatment; Immunoglobulinopathy; Mouse; Lymphoproliferative syndrome; Immunoblotting assay; Bacteria; Isolate; Serotype; ELISA assay
• ISSN: 1350-0872; 1465-2080
• DOI: 10.1099/mic.0.27443-0

Groupe de Recherche sur les Maladies Infectieuses du Porc (GREMIP), Département de Pathologie et Microbiologie, Faculté de Médecine Vétérinaire, Université de Montréal, 3200, Sicotte, CP 5000, Sainte-Hyacinthe, Québec, Canada J2S 7C6 Correspondence K. R. Mittal mittalk{at}medvet.umontreal.ca Monoclonal antibodies (MAbs) against Haemophilus parasuis were obtained by the fusion of SP2/0-Ag14 murine myeloma cells and spleen cells from BALB/c mice immunized with a whole-bacterial-cell suspension (WC) of H. parasuis strain SW124 (serotype 4). Two MAbs showing strong reactivity in ELISA were further characterized using SDS-PAGE and Western-blot assays. Different treatments of the WC indicated that MAbs 4D5 and 4G9 identified epitopes of proteinic and polysaccharidic nature, respectively. Electron microscopic examination revealed that, unlike the proteinic epitopes, the lipopolysaccharidic epitopes were exposed on the surface of the cell. Using coagglutination, Western-blot and dot-blot assays it was found that both MAbs recognized common epitopes of all the reference strains and field isolates of H. parasuis . None of the other bacteria tested reacted with the MAbs. These results indicated that both the proteinic and polysaccharidic antigens carried species-specific epitopes. It is suggested that these MAbs may potentially be useful for identification of H. parasuis isolates as well as for developing serological diagnostic tools. MAbs 4D5 and 4G9 were unable to kill H. parasuis in vitro in the presence of complement. However, an enhanced bacterial clearance from blood was observed in mice inoculated with either of the MAbs. Highly significant protection was observed in mice using MAb 4G9. This is believed to be the first report of MAbs capable of identifying common species-specific antigens of H. parasuis and of their implication in protection against challenge infection in mice. Abbreviations: BC, boiled cell suspension; CoA, coagglutination; LPS, lipopolysaccharide; MAb, monoclonal antibody; MOMP, major outer-membrane protein; OMP, outer-membrane protein; WC, whole-cell suspension