Identification of HLA-A2 restricted T-cell epitopes within the conserved region of the immunoglobulin G heavy-chain in patients with multiple myeloma.
OBJECTIVE
The aim of this study is the identification of HLA-A2 restricted T-cell epitopes in the conserved region of the immunoglobulin-G-heavy-chain (IgGH) that can be used for immunotherapy in multiple myeloma (MM) patients.


METHODS
After the IgGH gene sequence was scanned for HLA-A2 restricted T-cell epitopes with a high binding affinity to the MHC-I-complex, promising nona-peptides were synthesized. Peptide specific CD8+ T-cells were generated from peripheral blood mononuclear cells (PBMC) of healthy donors (HD) and patients with MM using peptide pulsed dendritic cells (DC) in vitro. The activation and cytotoxicity of CD8+ T-cells was analyzed by IFN-alpha ELISpot-assay and 51Chromium release-assay. HLA-A2 restriction was proven by blocking T-cell activation with anti-HLA-A2 antibodies.


RESULTS
Two HLA-A2 restricted T-cell epitopes-TLVTVSSAS derived from the IgGH-framework-region 4 (FR4) and LMISRTPEV from the constant region (CR)-induced expansion of specific CD8+ T-cells from PBMC in two of three (TLVTVSSAS) and one of three (LMISRTPEV) HD respectively. Specific T-cells were induced from PBMC in two of six (TLVTVSSAS) and eight of 19 (LMISRTPEV) patients with MM. Specific CD8+ T-cells also lysed peptide-pulsed target cells in 51Chromium release-assay. LMISRTPEV specific CD8+ T-cells from MM patients lysed specifically the HLA-A2+ IgG myeloma cell line XG-6.


CONCLUSIONS
We identified two HLA-A2 restricted T-cell epitopes-TLVTVSSAS and LMISRTPEV--which can yield an expansion of CD8+ T-cells with the ability to kill peptide-loaded target cells and HLA-A2+ IgG+ myeloma cells. We conclude that TLVTVSSAS and LMISRTPEV could be T-cell epitopes for immunotherapy in MM patients.
Belle
Sebastian
S
Department of internal medicine V University of HeidelbergHeidelberg,DE.
Han
Fang
F
Department of internal medicine V University of HeidelbergHeidelberg,DE.
Condomines
Maud
M
Immunopathologie des maladies tumorales et autoimmunes INSERM : U475IFR76Institut de recherche en biothérapieUniversité Montpellier ICentre de Recherche Inserm 99, Rue Puech Villa 34197 MONTPELLIER CEDEX 5,FR.|IRB, Institut de recherche en biothérapie CHRU MontpellierUniversité Montpellier IHopital Saint-Eloi 34000 Montpellier,FR.
Christensen
Olaf
O
Department of internal medicine V University of HeidelbergHeidelberg,DE.
Witzens-Harig
Mathias
M
Department of internal medicine V University of HeidelbergHeidelberg,DE.
Kasper
Bernd
B
Department of internal medicine V University of HeidelbergHeidelberg,DE.
Kleist
Christian
C
Department of transplantation immunology University of HeidelbergFR.
Terness
Peter
P
Department of transplantation immunology University of HeidelbergFR.
Moos
Marion
M
Department of internal medicine V University of HeidelbergHeidelberg,DE.
Cremer
Friedrich
F
Department of internal medicine V University of HeidelbergHeidelberg,DE.
Hose
Dirk
D
Department of internal medicine V University of HeidelbergHeidelberg,DE.
Ho
Anthony D
AD
Department of internal medicine V University of HeidelbergHeidelberg,DE.
Goldschmidt
Hartmut
H
Department of internal medicine V University of HeidelbergHeidelberg,DE.
Klein
Bernard
B
Immunopathologie des maladies tumorales et autoimmunes INSERM : U475IFR76Institut de recherche en biothérapieUniversité Montpellier ICentre de Recherche Inserm 99, Rue Puech Villa 34197 MONTPELLIER CEDEX 5,FR.|IRB, Institut de recherche en biothérapie CHRU MontpellierUniversité Montpellier IHopital Saint-Eloi 34000 Montpellier,FR.
Hundemer
Michael
M
Department of internal medicine V University of HeidelbergHeidelberg,DE.
D000595:Amino Acid Sequence; D017951:Antigen Presentation; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D003602:Cytotoxicity, Immunologic; D003713:Dendritic Cells / Q000276:immunology; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D015789:HLA-A2 Antigen / Q000276:immunology*; D006801:Humans; D007127:Immunoglobulin Constant Regions; D007074:Immunoglobulin G; D007143:Immunoglobulin Heavy Chains / Q000276:immunology*; D007167:Immunotherapy; D009101:Multiple Myeloma / Q000276:immunology* / Q000628:therapy
D018984:Epitopes, T-Lymphocyte; D015789:HLA-A2 Antigen; D007127:Immunoglobulin Constant Regions; D007074:Immunoglobulin G; D007143:Immunoglobulin Heavy Chains