title: An hour after immunization peritoneal B-1 cells are activated to migrate to lymphoid organs where within 1 day they produce IgM antibodies that initiate elicitation of contact sensitivity.
abstract: Elicitation of contact sensitivity (CS), a classic example of T cell-mediated immunity, requires Ag-specific IgM Abs to trigger an initiation process. This early process leads to local recruitment of CS-effector T cells after secondary Ag challenge. These Abs are produced by the B-1 subset of B cells within 1 day after primary skin immunization. In this study we report the surprising observation that B-1 cells in the peritoneal cavity are activated as early as 1 h after naive mice are painted with a contact-sensitizing Ag on the skin of the trunk and feet to begin the initiation of CS. B-1 cells in the spleen and draining lymph nodes produce the initiating Abs by 1 day after immunization, when we found increased numbers of Ag-specific IgM Ab-producing cells in these tissues by ELISPOT assay. Importantly, we show that contact-activated peritoneal B-1 cells migrate to these lymphoid tissues and then differentiate into Ag-specific IgM Ab-producing cells, resulting in specific CS-initiating IgM Abs in the serum by 1 day. Furthermore, pertussis toxin, which is known to inhibit signaling via G protein-coupled chemokines, inhibited the migration of contact-activated peritoneal B-1 cells to the lymphoid tissues, probably due to BLR-1 (Burkitt lymphoma receptor-1). These findings indicate that within 1 h after contact skin immunization, B-1 cells in the peritoneal cavity are activated to migrate to the lymphoid tissues by chemokine-dependent mechanisms to produce serum Ag-specific IgM Abs within 1 day after immunization, leading to local recruitment of CS-effector T cells.
authors.affiliation: Section of Allergy and Clinical Immunology, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06520-8013, USA.
authors.forename: Atsuko
authors.initials: A
authors.lastname: Itakura
authors.forename: Marian
authors.initials: M
authors.lastname: Szczepanik
authors.forename: Regis A
authors.initials: RA
authors.lastname: Campos
authors.forename: Vipin
authors.initials: V
authors.lastname: Paliwal
authors.forename: Monika
authors.initials: M
authors.lastname: Majewska
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Matsuda
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Takatsu
authors.forename: Philip W
authors.initials: PW
authors.lastname: Askenase
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology*; D002454:Cell Differentiation / Q000276:immunology; D002465:Cell Movement / Q000187:drug effects / Q000276:immunology; D003877:Dermatitis, Contact / Q000276:immunology*; D007075:Immunoglobulin M / Q000096:biosynthesis / Q000097:blood*; D008213:Lymphocyte Activation / Q000276:immunology*; D008221:Lymphoid Tissue / Q000276:immunology; D008297:Male; D051379:Mice; D018448:Models, Immunological; D010529:Peritoneal Cavity / Q000166:cytology*; D037342:Pertussis Toxin / Q000494:pharmacology; D013997:Time Factors
chemical_list: D007075:Immunoglobulin M; D037342:Pertussis Toxin