Efficient in vivo presentation of Listeria monocytogenes- derived CD4 and CD8 T cell epitopes in the absence of IFN-gamma.
IFN-gamma is an essential component of the early Listeria monocytogenes-specific immune response, and is also an important regulator of Ag processing and presentation. Ag presentation is required for the induction and also the effector function of antimicrobial T cells. To evaluate the effect of IFN-gamma on bacterial Ag presentation in vivo, macrophages and dendritic cells were separated from L. monocytogenes-infected tissues and analyzed with peptide-specific CD4 and CD8 T cell lines in a sensitive ELISPOT-based ex vivo Ag presentation assay. The comparison of professional APCs isolated from infected IFN-gamma-deficient and wild-type mice revealed different peptide presentation patterns of L. monocytogenes-derived CD8 T cell epitopes, while the presentation pattern of CD4 T cell epitopes remained unchanged. The further in vitro analysis of the generation of CD8 T cell epitopes revealed a peptide-specific effect of IFN-gamma on MHC class I-restricted Ag presentation. These results show that despite this modulation of the Ag presentation pattern of CD8 T cell epitopes, IFN-gamma is not generally required for the MHC class I- and MHC class II-restricted presentation of L. monocytogenes-derived antigenic peptides by professional APCs in vivo.
Skoberne
Mojca
M
Institut für Medizinische Mikrobiologie und Hygiene, Fakultät für Klinische Medizin Mannheim der Universität Heidelberg, Mannheim, Germany.
Geginat
Gernot
G
D000818:Animals; D017951:Antigen Presentation; D000942:Antigens, Bacterial / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002460:Cell Line; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000276:immunology; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D005260:Female; D015395:Histocompatibility Antigens Class I / Q000502:physiology; D000949:Histocompatibility Antigens Class II / Q000502:physiology; D007371:Interferon-gamma / Q000235:genetics / Q000502:physiology*; D008089:Listeria monocytogenes / Q000276:immunology*; D008088:Listeriosis / Q000276:immunology; D008264:Macrophages / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D010455:Peptides / Q000276:immunology; D015854:Up-Regulation
D000942:Antigens, Bacterial; D018984:Epitopes, T-Lymphocyte; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II; D010455:Peptides; D007371:Interferon-gamma