Natural Antibody Contributes to Host Defense against an Attenuated Brucella abortus virB Mutant
- 1 July 2009
- journal article
- Published by American Society for Microbiology in Infection and Immunity
- Vol. 77 (7), 3004-3013
- https://doi.org/10.1128/iai.01114-08
Abstract
Brucella abortus is an intracellular pathogen that persists within phagocytic cells of the reticuloendothelial system. To identify in vivo interactions between B. abortus and the host that lead to persistent infection, we studied the persistence of B. abortus and an isogenic virB mutant deficient in the VirB type IV secretion system (T4SS) in knockout mice. In contrast to control mice, mice lacking B cells ( Igh6 −/− ) were permissive for infection with the attenuated virB mutant. To determine the basis for this phenotype, we characterized immune functions of Igh6 −/− mice in the context of B. abortus infection. Igh6 −/− mice had greater numbers of extracellular bacteria in the spleen and increased early expression of proinflammatory cytokines during B. abortus infection. Further, a virB mutant, despite its wild-type level of survival, failed to elicit microgranuloma formation in the spleens of Igh6 −/− mice, suggesting a requirement for the T4SS to elicit this pathological change. Passive transfer of immunoglobulin G from naïve mice restored the ability of Igh6 −/− mice to control the persistence of the virB mutant by a complement-independent mechanism. Further, adoptive transfer of CD11b + cells from C57BL/6 mice to Igh6 −/− mice restored the ability of the knockout mice to limit the replication of the virB mutant in the spleen, suggesting that the Igh6 − / − mutation affects phagocyte function and that phagocyte function can be restored by natural antibody.Keywords
This publication has 45 references indexed in Scilit:
- Identification of VceA and VceC, two members of the VjbR regulon that are translocated into macrophages by the Brucella type IV secretion systemMolecular Microbiology, 2008
- Inactivation of the Type IV Secretion System Reduces the Th1 Polarization of the Immune Response toBrucella abortusInfectionInfection and Immunity, 2008
- Brucella Control of Dendritic Cell Maturation Is Dependent on the TIR-Containing Protein Btp1PLoS Pathogens, 2008
- Brucella Intracellular Replication Requires Trafficking Through the Late Endosomal/Lysosomal CompartmentTraffic, 2008
- Mice Lacking Components of Adaptive Immunity Show Increased Brucella abortus virB Mutant ColonizationInfection and Immunity, 2007
- The antiinflammatory activity of IgG: the intravenous IgG paradoxThe Journal of Experimental Medicine, 2007
- IgG Fc ReceptorsAnnual Review of Immunology, 2001
- DEVELOPMENT AND MATURATION OF SECONDARY LYMPHOID TISSUESAnnual Review of Immunology, 1999
- FcR γ chain deletion results in pleiotrophic effector cell defectsCell, 1994
- Comparative histopathology in BALB/c mice infected with virulent and attenuated strains of Brucella abortusVeterinary Immunology and Immunopathology, 1990