title: Role of B-1 cells in the immune response against an antigen encapsulated into phosphatidylcholine-containing liposomes.
abstract: B-1 lymphocytes comprise a unique subset of B cells that differ phenotypically, ontogenetically and functionally from conventional B-2 cells. A frequent specificity of the antibody repertoire of peritoneal B-1 cells is phosphatidylcholine. Liposomes containing phosphatidylcholine have been studied as adjuvants and their interaction with dendritic cells and macrophages has been demonstrated. However, the role of B-1 cells in the adjuvanticity of liposomes composed of phosphatidylcholine has not been explored. In the present work, we studied the contribution of B-1 cells to the humoral response against ovalbumin (OVA) encapsulated into dipalmitoylphosphatidylcholine (DPPC) and cholesterol-containing liposomes. BALB/X-linked immunodeficient (xid) mice, which are deficient in B-1 cells, showed quantitative and qualitative differences in the anti-OVA antibody response compared with wild-type animals after immunization with these liposomes. The OVA-specific immune response was significantly increased in the BALB/xid mice when reconstituted with B-1 cells from naive BALB/c mice. Our results indicate the internalization of DPPC-containing liposomes by these cells and their migration from the peritoneal cavity to the spleen. Phosphatidylcholine significantly contributed to the immunogenicity of liposomes, as DPPC-containing liposomes more effectively stimulated the anti-OVA response compared with vesicles composed of dipalmitoylphosphatidylglycerol. In conclusion, we present evidence for a cognate interaction between B-1 cells and phosphatidylcholine liposomes, modulating the immune response to encapsulated antigens. This provides a novel targeting approach to assess the role of B-1 cells in humoral immunity.
authors.affiliation: Center for Protein Studies, Faculty of Biology, University of Havana, Havana 10400, Cuba.
authors.forename: Yoelys
authors.initials: Y
authors.lastname: Cruz-Leal
authors.affiliation: Research and Development Division, Center of Molecular Immunology (CIM), Havana 11600, Cuba.
authors.forename: Yoan
authors.initials: Y
authors.lastname: Machado
authors.affiliation: Research and Development Division, Center of Molecular Immunology (CIM), Havana 11600, Cuba.
authors.forename: Alejandro
authors.initials: A
authors.lastname: López-Requena
authors.affiliation: Center for Protein Studies, Faculty of Biology, University of Havana, Havana 10400, Cuba.
authors.forename: Liem
authors.initials: L
authors.lastname: Canet
authors.affiliation: Center for Protein Studies, Faculty of Biology, University of Havana, Havana 10400, Cuba.
authors.forename: Rady
authors.initials: R
authors.lastname: Laborde
authors.affiliation: Discipline of Immunology, Department of Microbiology, Immunology and Parasitology, Universidade Federal de São Paulo, 4023-900, SP, Brazil.
authors.forename: Anuska Marcelino
authors.initials: AM
authors.lastname: Álvares
authors.affiliation: Discipline of Immunology, Department of Microbiology, Immunology and Parasitology, Universidade Federal de São Paulo, 4023-900, SP, Brazil.
authors.forename: María F
authors.initials: MF
authors.lastname: Lucatelli Laurindo
authors.affiliation: Research and Development Division, Center of Molecular Immunology (CIM), Havana 11600, Cuba.
authors.forename: Julio F
authors.initials: JF
authors.lastname: Santo Tomas
authors.affiliation: Center for Protein Studies, Faculty of Biology, University of Havana, Havana 10400, Cuba.
authors.forename: María E
authors.initials: ME
authors.lastname: Alonso
authors.affiliation: Center for Protein Studies, Faculty of Biology, University of Havana, Havana 10400, Cuba.
authors.forename: Carlos
authors.initials: C
authors.lastname: Alvarez
authors.affiliation: Department of Microbiology, Immunology and Parasitology, Universidade Federal de São Paulo, 4023-900, SP, Brazil and.
authors.forename: Renato A
authors.initials: RA
authors.lastname: Mortara
authors.affiliation: Discipline of Immunology, Department of Microbiology, Immunology and Parasitology, Universidade Federal de São Paulo, 4023-900, SP, Brazil.
authors.forename: Ana F
authors.initials: AF
authors.lastname: Popi
authors.affiliation: Discipline of Immunology, Department of Microbiology, Immunology and Parasitology, Universidade Federal de São Paulo, 4023-900, SP, Brazil Universidade Paulista UNIP, São Paulo, Brazil.
authors.forename: Mario
authors.initials: M
authors.lastname: Mariano
authors.affiliation: Research and Development Division, Center of Molecular Immunology (CIM), Havana 11600, Cuba.
authors.forename: Rolando
authors.initials: R
authors.lastname: Pérez
authors.affiliation: Center for Protein Studies, Faculty of Biology, University of Havana, Havana 10400, Cuba mlanio@fbio.uh.cu.
authors.forename: María E
authors.initials: ME
authors.lastname: Lanio
mesh_terms: D000276:Adjuvants, Immunologic; D000818:Animals; D000906:Antibodies / Q000276:immunology; D000917:Antibody Formation / Q000276:immunology; D000918:Antibody Specificity; D000941:Antigens / Q000737:chemistry / Q000276:immunology*; D016175:B-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism; D002465:Cell Movement; D005260:Female; D007114:Immunization; D008081:Liposomes; D051379:Mice; D010047:Ovalbumin / Q000276:immunology; D010713:Phosphatidylcholines / Q000737:chemistry / Q000276:immunology; D013154:Spleen / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D000906:Antibodies; D000941:Antigens; D008081:Liposomes; D010713:Phosphatidylcholines; D010047:Ovalbumin
keywords: B-1 lymphocytes; adjuvants; humoral response