title: Characterization of a Monoclonal Antibody Directed against Mytilus spp Larvae Reveals an Antigen Involved in Shell Biomineralization.
abstract: The M22.8 monoclonal antibody (mAb) developed against an antigen expressed at the mussel larval and postlarval stages of Mytilus galloprovincialis was studied on adult samples. Antigenic characterization by Western blot showed that the antigen MSP22.8 has a restricted distribution that includes mantle edge tissue, extrapallial fluid, extrapallial fluid hemocytes, and the shell organic matrix of adult samples. Other tissues such as central mantle, gonadal tissue, digestive gland, labial palps, foot, and byssal retractor muscle did not express the antigen. Immunohistochemistry assays identified MSP22.8 in cells located in the outer fold epithelium of the mantle edge up to the pallial line. Flow cytometry analysis showed that hemocytes from the extrapallial fluid also contain the antigen intracellularly. Furthermore, hemocytes from hemolymph have the ability to internalize the antigen when exposed to a cell-free extrapallial fluid solution. Our findings indicate that hemocytes could play an important role in the biomineralization process and, as a consequence, they have been included in a model of shell formation. This is the first report concerning a protein secreted by the mantle edge into the extrapallial space and how it becomes part of the shell matrix framework in M. galloprovincialis mussels.
authors.affiliation: Immunology, Biomedical Research Center (CINBIO) and Institute of Biomedical Research of Vigo (IBIV), University of Vigo, Vigo, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Calvo-Iglesias
authors.affiliation: R&D deparment, NanoImmunoTech, Vigo, Spain.
authors.forename: Daniel
authors.initials: D
authors.lastname: Pérez-Estévez
authors.affiliation: Immunology, Biomedical Research Center (CINBIO) and Institute of Biomedical Research of Vigo (IBIV), University of Vigo, Vigo, Spain.
authors.forename: Silvia
authors.initials: S
authors.lastname: Lorenzo-Abalde
authors.affiliation: Immunology, Biomedical Research Center (CINBIO) and Institute of Biomedical Research of Vigo (IBIV), University of Vigo, Vigo, Spain.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Sánchez-Correa
authors.affiliation: Veterinary Clinical Sciences, Veterinary Faculty, University of Santiago de Compostela, Lugo, Spain.
authors.forename: María Isabel
authors.initials: MI
authors.lastname: Quiroga
authors.affiliation: Centro de Investigacións Mariñas (CIMA), Consellería do Medio Rural e do Mar, Vilanova de Arousa, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Fuentes
authors.affiliation: Immunology, Biomedical Research Center (CINBIO) and Institute of Biomedical Research of Vigo (IBIV), University of Vigo, Vigo, Spain.
authors.forename: África
authors.initials: Á
authors.lastname: González-Fernández
mesh_terms: D060105:Animal Shells / Q000254:growth & development / Q000276:immunology*; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000941:Antigens / Q000276:immunology* / Q000502:physiology; D015153:Blotting, Western; D002113:Calcification, Physiologic / Q000276:immunology* / Q000502:physiology; D005434:Flow Cytometry; D006434:Hemocytes / Q000276:immunology; D006458:Hemolymph / Q000276:immunology; D007814:Larva / Q000276:immunology; D049878:Mytilus / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000941:Antigens