Open AccessSurvival ofSalmonella entericaSerovar Typhimurium within Late Endosomal-Lysosomal Compartments of B Lymphocytes Is Associated with the Inability To Use the Vacuolar Alternative Major Histocompatibility Complex Class I Antigen-Processing Pathway
Author(s) -
Roberto Rosales-Reyes,
Celia Alpuche-Aranda,
María de la Luz Ramírez-Aguilar,
Denisse Castro-Eguiluz,
Vianney Ortiz-Navarrete
Publication year - 2005
Publication title -
infection and immunity
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.508
H-Index - 220
eISSN - 1070-6313
pISSN - 0019-9567
DOI - 10.1128/iai.73.7.3937-3944.2005
Subject(s) - biology , salmonella enterica , endosome , antigen , major histocompatibility complex , microbiology and biotechnology , salmonella , macrophage , cd8 , antigen processing , mhc class ii , lysosome , mhc class i , immunology , in vitro , bacteria , biochemistry , intracellular , genetics , enzyme
Gamma interferon (IFN-gamma)-activated macrophages use an alternative processing mechanism to present Salmonella antigens to CD8(+) T lymphocytes. This pathway involves processing of antigen in a vacuolar compartment followed by secretion and loading of antigenic peptides to major histocompatibility complex class I (MHC-I) molecules on macrophage cell surface and bystander cells. In this study, we have shown that B lymphocytes are not able to process Salmonella antigens using this alternative pathway. This is due to differences in Salmonella enterica serovar Typhimurium-containing vacuoles (SCV) when comparing late endosomal-lysosomal processing compartments in B lymphocytes to those in macrophages. The IFN-gamma-activated IC21 macrophage cell line and A-20 B-cell line were infected with live or dead Salmonella enterica serovar Typhimurium. The SCV in B cells were in a late endosomal-lysosomal compartment, whereas SCV in macrophages were remodeled to a non-characteristic late endosomal-lysosomal compartment over time. Despite the difference in SCV within macrophages and B lymphocytes, S. enterica serovar Typhimurium survives more efficiently within the IFN-gamma-activated B cells than in activated macrophage cell lines. Similar results were found during in vivo acute infection. We determined that a lack of remodeling of late endosomal-lysosomal compartments by live Salmonella infection in B lymphocytes is associated with the inability to use the alternative MHC-I antigen-processing pathway, providing a survival advantage to the bacterium. Our data also suggest that the B lymphocyte late endosome-lysosome environment allows the expression of Salmonella virulence mechanisms favoring B lymphocytes in addition to macrophages and dendritic cells as a reservoir during in vivo infection.