title: Cellular Dynamics of Memory B Cell Populations: IgM+ and IgG+ Memory B Cells Persist Indefinitely as Quiescent Cells.
abstract: Despite their critical role in long-term immunity, the life span of individual memory B cells remains poorly defined. Using a tetracycline-regulated pulse-chase system, we measured population turnover rates and individual t1/2 of pre-established Ag-induced Ig class-switched and IgM-positive memory B cells over 402 d. Our results indicate that, once established, both IgG-positive and less frequent IgM-positive memory populations are exceptionally stable, with little evidence of attrition or cellular turnover. Indeed, the vast majority of cells in both pools exhibited t1/2 that appear to exceed the life span of the mouse, contrasting dramatically with mature naive B cells. These results indicate that recall Ab responses are mediated by stable pools of extremely long-lived cells, and suggest that Ag-experienced B cells employ remarkably efficient survival mechanisms.
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA 19104.
authors.forename: Derek D
authors.initials: DD
authors.lastname: Jones
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA 19104.
authors.forename: Joel R
authors.initials: JR
authors.lastname: Wilmore
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA 19104 dallman@mail.med.upenn.edu.
authors.forename: David
authors.initials: D
authors.lastname: Allman
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D002470:Cell Survival; D007074:Immunoglobulin G / Q000235:genetics / Q000276:immunology*; D007075:Immunoglobulin M / Q000235:genetics / Q000276:immunology*; D007156:Immunologic Memory / Q000502:physiology*; D051379:Mice; D008822:Mice, Transgenic; D013997:Time Factors
chemical_list: D007074:Immunoglobulin G; D007075:Immunoglobulin M