The spontaneous CD8+ T-cell response to HLA-A2-restricted NY-ESO-1b peptide in hepatocellular carcinoma patients.
OBJECTIVE
Hepatocellular carcinoma (HCC) can express various cancer-testis antigens including NY-ESO-1, members of the SSX family, members of the MAGE family, SCP-1, and CTP11. Immunotherapy directed against these antigens is a potential alternative treatment for HCC. To date, it remains unclear whether HCC patients have spontaneous immune responses to these tumor antigens. The objectives of this study were to measure immune responses to NY-ESO-1, a promising cancer vaccine candidate, in HCC patients using the HLA-A2-restricted NY-ESO-1b peptide (p157-165) to measure cellular responses and whole protein to measure antibody responses.


METHODS
In HLA-A2(+) patients with NY-ESO-1(+) HCC, we analyzed T-cell antigen-dependent interferon (IFN)-gamma and/or Granzyme B release by enzyme-linked immunospot (ELISPOT) assay and IFN-gamma-producing intracellular cytokine flow cytometry (CytoSpot). As an assay independent of T-cell function, we performed tetramer staining. Antibodies to whole NY-ESO-1 were assayed by enzyme-linked immunosorbent assay.


RESULTS
The frequency of specific CD8(+) T-cell responses to NY-ESO-1b in 28 NY-ESO-1 mRNA(+)HLA-A2(+) HCC patients was 35.7% (10 of 28). The average magnitude of effector CD8(+) T cells was 0.3% (89 +/- 59 per 2.5 x 10(4) CD8(+) cells) and 1.2% as measured by IFN-gamma release ELISPOT and CytoSpot assays, respectively. These in vitro induced NY-ESO-1b-specific CD8(+) T cells can also recognize HepG2 cells transfected with pcDNA3.1-NY-ESO-1 in both IFN-gamma and Granzyme B ELISPOT assays. Frequencies of NY-ESO-1b-specific T cells in several patients were confirmed by tetramer staining. Nonfunctional tetramer(+)CD8(+) T cells were also present. The CD8(+) T-cell response was apparently increased in patients with late-stage HCC. A discordance between antibody and CD8(+) T-cell responses in HCC patients was observed.


CONCLUSIONS
The elevated frequency of specific CD8(+) T-cell responses to NY-ESO-1b in NY-ESO-1 mRNA(+)HLA-A2(+) HCC patients suggests that NY-ESO-1 is appropriate for use in the immunotherapy of HCC patients.
Shang
Xiao-Ying
XY
Department of Immunology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, People's Republic of China.
Chen
Hong-Song
HS
Zhang
Hua-Gang
HG
Pang
Xue-Wen
XW
Qiao
Huan
H
Peng
Ji-Run
JR
Qin
Li-Ling
LL
Fei
Ran
R
Mei
Ming-Hui
MH
Leng
Xi-Sheng
XS
Gnjatic
Sacha
S
Ritter
Gerd
G
Simpson
Andrew J G
AJ
Old
Lloyd J
LJ
Chen
Wei-Feng
WF
D000328:Adult; D000368:Aged; D000917:Antibody Formation; D000951:Antigens, Neoplasm / Q000494:pharmacology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D019496:Cancer Vaccines / Q000276:immunology*; D006528:Carcinoma, Hepatocellular / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D053804:Granzymes; D015789:HLA-A2 Antigen / Q000276:immunology; D006801:Humans; D007118:Immunoassay; D007167:Immunotherapy / Q000379:methods; D007371:Interferon-gamma / Q000494:pharmacology; D008113:Liver Neoplasms / Q000276:immunology*; D008297:Male; D008565:Membrane Proteins / Q000494:pharmacology*; D008875:Middle Aged; D010446:Peptide Fragments; D012697:Serine Endopeptidases / Q000494:pharmacology
D000951:Antigens, Neoplasm; C104948:CTAG1B protein, human; D019496:Cancer Vaccines; D015789:HLA-A2 Antigen; D008565:Membrane Proteins; D010446:Peptide Fragments; D007371:Interferon-gamma; C509213:GZMB protein, human; D053804:Granzymes; D012697:Serine Endopeptidases