Paucity of functional T-cell memory to melanoma antigens in healthy donors and melanoma patients.
The functional characteristics of CD8+ T cells specific for melanoma antigens (MAs) have often been defined after in vitro culture using nonprofessional antigen-presenting cells. We have examined CD8+ T-cell immunity to MAs and a viral antigen (influenza) in uncultured T cells of healthy donors and melanoma patients using autologous, mature, monocyte-derived dendritic cells (DCs) pulsed with peptide antigens and viral vectors. Antigen-specific IFN-gamma-producing T cells reactive with HLA-A*0201-restricted peptides from four melanoma antigens (MelanA/MART-1, MAGE-3, tyrosinase, and gp100) were detected only at low frequencies (<30 per 2 x 10(5) peripheral blood mononuclear cells for each of the MAs) from HLA-A2.1-positive healthy donors (n = 12) and patients with stages III/IV melanoma (n = 8). Detection of MA-specific, but not influenza matrix peptide (Flu-MP)-specific, T cells required a high concentration (10 microg/ml) of the peptide in this assay. Furthermore, these T cells did not recognize endogenously processed antigen on tumor cell lines or cells infected with viral vectors capable of expressing MAs. The use of autologous, mature DCs led to a significant increase in the number of Flu-MP, but not MA-specific, T cells in 16-h ELISPOT assays for both melanoma patients and healthy donors. In 1-week cocultures with DCs pulsed with 10 microg/ml peptide, MelanA/MART-1-specific T cells did not readily proliferate or differentiate into lytic effectors, in contrast to strong influenza-specific lytic responses. Therefore, despite distinct memory responses to influenza antigens, melanoma patients and healthy controls have a paucity of MA-reactive memory T cells, failing to rapidly generate IFN-gamma-secreting lytic effectors in short-term assays, even when stimulated by DCs.
Dhodapkar
M V
MV
Laboratory of Cellular Physiology and Immunology, The Rockefeller University, New York, New York 10021, USA. dhodapm@rockvax.rockefeller.edu
Young
J W
JW
Chapman
P B
PB
Cox
W I
WI
Fonteneau
J F
JF
Amigorena
S
S
Houghton
A N
AN
Steinman
R M
RM
Bhardwaj
N
N
D000941:Antigens / Q000378:metabolism; D000951:Antigens, Neoplasm; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D018920:Coculture Techniques; D003713:Dendritic Cells / Q000276:immunology; D015234:HLA-A Antigens / Q000276:immunology; D006801:Humans; D007156:Immunologic Memory; D007371:Interferon-gamma / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000276:immunology; D058965:MART-1 Antigen; D008545:Melanoma / Q000276:immunology*; D008562:Membrane Glycoproteins / Q000276:immunology; D014442:Monophenol Monooxygenase / Q000276:immunology; D009363:Neoplasm Proteins / Q000276:immunology; D009369:Neoplasms / Q000276:immunology / Q000378:metabolism; D010455:Peptides / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology* / Q000502:physiology*; D013997:Time Factors; D014407:Tumor Cells, Cultured; D058951:gp100 Melanoma Antigen
D000941:Antigens; D000951:Antigens, Neoplasm; D015234:HLA-A Antigens; C072013:MAGEA3 protein, human; D058965:MART-1 Antigen; C548667:MLANA protein, human; D008562:Membrane Glycoproteins; D009363:Neoplasm Proteins; C548637:PMEL protein, human; D010455:Peptides; D058951:gp100 Melanoma Antigen; D007371:Interferon-gamma; D014442:Monophenol Monooxygenase