A Novel Approach of Direct Ex Vivo Epitope Mapping Identifies Dominant and Subdominant CD4 and CD8 T Cell Epitopes from Listeria monocytogenes

• Published in: The Journal of immunology (1950) 2001-02, Vol.166 (3), p.1877-1884
• Main Authors: Geginat, Gernot, Schenk, Simone, Skoberne, Mojca, Goebel, Werner, Hof, Herbert
• Format: Article
• Language: English
• Subjects: Animals; Bacterial Proteins - analysis; Bacterial Proteins - immunology; Bacterial Toxins; CD4 antigen; CD4-Positive T-Lymphocytes - immunology; CD4-Positive T-Lymphocytes - metabolism; CD4-Positive T-Lymphocytes - microbiology; CD8 antigen; CD8-Positive T-Lymphocytes - immunology; CD8-Positive T-Lymphocytes - metabolism; CD8-Positive T-Lymphocytes - microbiology; Cell Line; Enzyme-Linked Immunosorbent Assay - methods; Epitope Mapping - methods; Epitopes, T-Lymphocyte - analysis; Epitopes, T-Lymphocyte - immunology; Female; Heat-Shock Proteins - analysis; Heat-Shock Proteins - immunology; Hemolysin Proteins; Histocompatibility Antigens Class I - analysis; Histocompatibility Antigens Class I - immunology; Histocompatibility Antigens Class II - analysis; Histocompatibility Antigens Class II - immunology; Immunodominant Epitopes - analysis; Immunodominant Epitopes - immunology; Immunologic Memory; Immunophenotyping; Listeria monocytogenes; Listeria monocytogenes - immunology; Lymphocyte Activation; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Peptide Library; T-Lymphocyte Subsets - immunology; T-Lymphocyte Subsets - metabolism; T-Lymphocyte Subsets - microbiology
• ISSN: 0022-1767; 1550-6606
• DOI: 10.4049/jimmunol.166.3.1877

We used a novel approach for the direct ex vivo identification and characterization of T cell epitopes based on the screening of peptide spot libraries with freshly isolated splenocytes in a sensitive enzyme-linked immunospot (ELISPOT) assay. This technique was applied for the analysis of splenocytes from Listeria monocytogenes-infected BALB/c and C57BL/6 mice. The screening of peptide spot libraries covering the whole listeriolysin O and p60 of L. monocytogenes confirmed all known CD4 and CD8 T cell epitopes of these proteins and additionally revealed six new H-2(d) and six new H-2(b)-restricted T cell epitopes. New epitopes were categorized into CD4 and CD8 T cell epitopes by ex vivo ELISPOT analysis with separated T cell populations. The quantitative analysis of cells reactive with these CD4 and CD8 T cell epitopes revealed the existence of dominant and subdominant CD4 and CD8 T cell populations during L. monocytogenes infection. As a consequence of these data we suggest that ELISPOT-based screening of peptide spot libraries could be a general approach for the rapid identification and characterization of pathogen-specific T cell populations during various infectious diseases.