title: Memory B cells express a phenotype consistent with migratory competence after secondary but not short-term primary immunization.
abstract: The cell surface phenotype of dinitrophenol (DNP)-specific memory B cells, defined by their capacity to transfer IgG responses into syngeneic irradiated recipients, was assessed using two markers of relevance to lymphocyte migratory properties: (i) peanut agglutinin, which binds to terminal galactosyl residues expressed at high levels by several nonmigrating lymphocyte subsets and, among lymph node B cells, is highly specific for germinal center cells; and (ii) MEL-14, a monoclonal antibody specific for lymphocyte surface receptors required for migration from the blood into peripheral lymph nodes. At various times after primary or secondary immunization with DNP-keyhole limpet hemocyananin (KLH), lymph node B cells were separated by fluorescence-activated cell sorting on the basis of staining with PNA and/or MEL-14, and the presence of B-memory cells in each fraction was assessed by adoptive transfer with antigen (DNP-KLH) and helper T cells. One week after immunization, most of the memory sorted in the PNAhi population, confirming a previous report by R. F. Coico, B. S. Bhogal, and G. J. Thorbecke (J. Immunol. 131, 2254, 1983) that early memory B cells or their precursors are contained within the germinal center cell population, a population which is known to be MEL-14- and migratory-incompetent. Six weeks after primary stimulation, however, the bulk of memory cells, unlike germinal center cells, were MEL-14hi. After secondary immunization, memory was still predominantly MEL-14+ and PNAlo, although in some experiments adoptive responses were transferred by all sorted fractions. The results are consistent with the hypothesis that antigen-specific B cells initially undergo local (sessile) differentiation and proliferation in germinal centers, where they develop the capacity for adoptive transfer of antigen-specific secondary responses, but that with continued development their long-lived memory-containing progeny express a phenotype permitting their reentry into the recirculating lymphocyte pool.
authors.affiliation: Department of Histology, Medical Faculty, Free University, Amsterdam, The Netherlands.
authors.forename: G
authors.initials: G
authors.lastname: Kraal
authors.forename: I L
authors.initials: IL
authors.lastname: Weissman
authors.forename: E C
authors.initials: EC
authors.lastname: Butcher
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D001402:B-Lymphocytes / Q000145:classification* / Q000276:immunology / Q000637:transplantation; D002465:Cell Movement; D004136:Dinitrobenzenes / Q000276:immunology; D005260:Female; D007116:Immunization, Passive; D007117:Immunization, Secondary; D007074:Immunoglobulin G / Q000096:biosynthesis; D007156:Immunologic Memory; D037102:Lectins; D008198:Lymph Nodes / Q000166:cytology / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D019887:Peanut Agglutinin; D013997:Time Factors
chemical_list: D000911:Antibodies, Monoclonal; D004136:Dinitrobenzenes; D007074:Immunoglobulin G; D037102:Lectins; D019887:Peanut Agglutinin