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*
Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, United Kingdom;
II Medizinische Klinik, Hãmatologie-Onkologie, Krankenhaus Nordwest, Frankfurt, Germany;
Ludwig Institute for Cancer Research, New York Branch at Memorial Sloan-Kettering Cancer Center, New York, NY 10021;
§
Therion Biologics Corporation, Cambridge, MA 02142; and
¶
Department of Pathology, Cornell University Medical College, New York, NY 10021
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Abstract |
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 Top Abstract IntroductionMaterials and MethodsResultsDiscussionReferences |
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Introduction |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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One of the most promising of these new SEREX Ags is NY-ESO-1, which is found in 30% of breast, prostate, and ovarian cancer, as well as melanoma, but not in normal tissues, with the exception of testis (3). Expression of NY-ESO-1 by tumor cells in melanoma patients stimulates a combined humoral and cellular response in a significant percentage of patients (4). The high immunogenicity of NY-ESO-1 and its broad tumor expression make this protein a very promising target for tumor-specific vaccination strategies. If NY-ESO-1 epitopes were presented by different tumor cells and recognized by CTL, then vaccines designed to boost CTL responses against NY-ESO-1 epitopes may be useful in the treatment of these tumors.
HLA-A2-binding NY-ESO-1 peptides, capable of being recognized by CTL, have recently been described (5). However, very little is known about the processing requirements for the generation of these epitopes, and whether tumor cells are efficiently lysed by NY-ESO-1-specific CTL. As some tumor epitopes may be generated so poorly by tumor cells that CTL fail to kill them efficiently (6), we sought to analyze the processing and presentation of a defined NY-ESO-1 epitope. Attention was focused on the role of the proteasome subunits low molecular protein (LMP) 2 and LMP7, as a recent report raised the possibility that processing of certain tumor target proteins by LMP-positive cells may result in a poor presentation of tumor CTL epitopes (7). Since this work requires the development of highly specific CTL lines, we used MHC class I tetramers to define and clone a population of NY-ESO-1-specific CTL, using previously described protocols (8). These clones allowed confirmation of the identity of an HLA-A2-restricted NY-ESO-1 epitope presented by NY-ESO-1-positive tumors and analysis of its processing requirements. This epitope, NY-ESO-1 157–165, contains a cysteine at carboxyl terminus of the peptide. Since it is known that cysteinylation and dimerization of cysteine residues may reduce antigenicity of synthetic peptides binding to MHC class I molecules (9), we sought to study whether modification of cysteine 165 in the NY-ESO-1 157–165 epitope would increase its immunogenicity.
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Materials and Methods |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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Peptides were synthesized by standard solid-phase chemistry on a multiple peptide synthesizer (Genosys, The Woodlands, TX) by using F-moc for transient NH2-terminal protection. All peptides were >90% pure, as indicated by analytical HPLC. Lyophilized peptides were diluted in DMSO and stored at -20°C.
Cells
The NY-ESO-1-positive tumor line NW 37 was cultured in Dulbecco medium (Life Technologies, Grand Island, NY) supplemented with 10% FCS. NY-ESO-1-specific CTL clones were stimulated with a mixture of allogeneic irradiated PBL- and EBV-transformed B cells, and PHA (5 µg/ml), and cultured in 5% human serum with IL-2 (200 U/ml; Chiron, Emeryville, CA), as described (8).
PBL from melanoma patients were stimulated with either 100 or 10 nM peptide in the presence or absence of 200 µM TCEP (Pierce, Rockford, IL). Peptides were added to total PBL, and cells were cultured in Iscove’s medium supplemented with 5% human serum and IL-2 (200 U/ml). After 1 wk in culture, cells were stimulated with irradiated T2 cells pulsed with either 100 or 10 nM’m peptide in the presence or absence of 200 µM tris(2-carboxyethyl)phosphine hydrochloride (TCEP). T2 cells and PBL were mixed at a ratio of 1:1. Cells were stained with HLA-A2 tetramers containing the peptide NY-ESO-1 157–165.
MHC class I tetramers
Tetrameric MHC class I/peptide complexes were synthesized as described (10, 11). Briefly, purified HLA heavy chain and ß2-microglobulin (ß2m) were synthesized by means of a prokaryotic expression system (pET; R&D Systems, Minneapolis, MN). The heavy chain was modified by deletion of the trans-membrane and cytosolic tail and COOH-terminal addition of a sequence containing the Bir-A enzymatic biotinylation site. Heavy chain, ß2m, and peptide were refolded by dilution. The 45-kDa refolded product was isolated by FPLC and then biotinylated by Bir-A (Avidity) in the presence of biotin, adenosine 5'-triphosphate, and Mg2+ (all from Sigma, St. Louis, MO). Streptavidin-PE conjugate (Sigma) was added in 1:4 molar ratio.
mAbs and flow cytometry immunofluorescence analysis
Cells were stained with tetramers for 15 min at 37°C, then washed in PBS/1% FCS at 37°, before incubating with TriColor anti-CD8 (Caltag, Burlingame, CA) for 30 min on ice. Cells were washed three times in ice-cold PBS/1% FCS and analyzed by flow cytometry using CellQuest software. Cloning of tetramer-positive CD8+ cells was conducted, as described (8), from a patient with an NY-ESO-1 positive melanoma (NW 14), after pulsing the PBL with NY-ESO-1 157–165 peptide 10 µM, and culturing in IL-2 200 U/ml for 5 days. HLA-A2 surface expression in T2 cells was measured by staining T2 cells with the HLA-A2-specific Ab BB7.2. T2 cells were incubated with peptides overnight at 37°C in RPMI without FCS. Cells were then washed and stained with 10 µg/ml of BB7.2, and washed and stained with FITC-labeled goat anti-mouse Ig.
Chromium release assay
Ag recognition was assessed using target cells (T2 or melanoma) labeled with 51Cr for 90 min at 37°C and washed twice. Labeled target cells (5000 cells in 100 µl) were then added to varying numbers of effector cells (100 µl) in U-bottom microwells in presence or absence of peptides at different concentrations. Target cells were incubated with peptides for 30 min at 37°C before the addition of effector cells. Reducing agents DTT and TCEP were added together with target cells and peptides before adding effector cells. Chromium release was measured after incubation for 4 h at 37°C. The percent specific lysis was calculated as: 100 x [(experimental - spontaneous release)/(total - spontaneous release)].
Immunoprecipitation of metabolically labeled HLA-A2
T2 cells were resuspended at 2 x 107/ml in methionine and cysteine-free R10 (RPMI 1640 with added glutamine (2 mM), penicillin (100 IU/ml), streptomycin (100 µg/ml), and FCS (10% v/v)), for 1 h at 37°C. Promix (143 µCi; 70% [35S]methionine and 30% [35S]cysteine; Amersham, Arlington Heights, IL) was then added, and the mixture was incubated for 60 min. Cells were lysed in 0.5 ml ice-cold lysis buffer (150 mM NaCl, 50 mM Tris-HCl (pH 7.5), 5 mM EDTA, 0.5% Nonidet P-40, 2 mM PMSF, and 5 mM iodoacetamide), followed by centrifugation of pellet nuclei. Lysates were precleared overnight with Pansorbin at 4°C and immunoprecipitated with 15 µg/ml of BB7.2 and protein A-coated Sepharose beads. Following extensive washing, proteins were eluted from the beads using standard SDS-PAGE loading sample buffer and heated at 95°C for 5 min.
Vaccinia infection
Target cells were infected with vaccinia at a multiplicity of infection of 5 for 90 min and, after washing, suspended in R10. Infected cells were grown either overnight or for 4 h. The vaccinia expressing the full-length NY-ESO-1 was made by cloning NY-ESO-1 cDNA into the thymidine kinase gene using the vector pSC11, as previously described (12). An influenza matrix vaccinia (Matrix-Vac) was used as a specificity control. This vaccinia has been described previously (12).
Lactacystin treatment of target cells
A total of 106 cells was suspended in 50 µl of R10 media containing 100 µM lactacystin for 1 h before addition of vaccinia in 50 µl at multiplicity of infection of 5. After 90-min infection, cells were washed and suspended in 5 ml of R10 containing 1 µM lactacystin and grown overnight to allow expression of the NY-ESO-1 and influenza matrix genes.
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Results |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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HLA-A2 tetramers containing the peptide NY-ESO-1 157–165 were
used to sort and clone tetramer+
CD8+ cells from melanoma patients’ PBL (4, 8). Four NY-ESO-1-specific clones were expanded from a melanoma
patient (Fig. 1
A) and tested
for killing specificity. NY-ESO-1-positive melanoma cells were
efficiently killed, demonstrating that intracellular processing of the
NY-ESO-1 protein results in the generation of a peptide recognized by
NY-ESO-1 157–165-specific CTL (Fig. 1B). Similar results
were obtained with NY-ESO-1-specific CTL lines expanded from another
melanoma patient (data not shown). Three overlapping HLA-A2-binding
NY-ESO-1 peptides (NY-ESO-1 157–165; NY-ESO-1 157–167; and NY-ESO-1
155–163; see Table I) were previously
shown to be seen by polyclonal CTL lines derived from melanoma patients
(5). It remained to be established whether lysis of target
cells pulsed with these overlapping peptides was due to different CTL
clones, each with different TCR specificity, or whether all three
peptides were recognized by a single CTL clone. The use of
tetramer-sorted NY-ESO-1-specific CTL clones allowed confirmation of
the identity of the CTL determinant recognized by a single
NY-ESO-1-specific TCR. We demonstrated that the 9-mer peptide NY-ESO-1
157–165, 10-mer peptide NY-ESO-1 157- 166, and the 11-mer peptide
157–167 were all recognized by NY-ESO-1-specific CTL clones, while the
overlapping peptide NY-ESO-1 155–163 and the 8-mer peptide NY-ESO-1
157–164 were not seen (Figs. 1C and 4A). These
results demonstrate that TCR recognition of the peptide NY-ESO-1
157–165 by a defined CTL clone requires the presence of either or both
glutamine 164 and cysteine 165, hence suggesting that modification of
these two residues may alter the efficiency of CTL recognition.
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A). As a control for these
results, we showed that the LMP-negative cells .174/TAP failed to
present the LMP7-dependent influenza matrix epitope 58–66, while
transfection of LMP7 relieved its block in presentation
(12). Consistent with these findings, we showed that
presentation of the NY-ESO-1 157–165 epitope was not altered by the
addition of the proteasome inhibitor lactacystin (Fig. 2B),
while proteasome inhibition by lactacystin in .174/TAP cells relieved
the presentation of the LMP7-dependent influenza matrix epitope 58–66
(Fig. 2B) (12). These results, while confirming
that generation of the influenza matrix epitope 58–66 is impaired in
LMP7-negative cells (12), demonstrate that generation of
the NY-ESO-1 157–165 epitope is resistant to the effect of proteasome
inhibitors and is not dependent on the presence or absence of LMP
proteasome subunits.
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It is known that modification of cysteine residues contained
within antigenic peptides may affect the immunogenicity of MHC class
I-restricted epitopes (9, 15). As the peptide NY-ESO-1
157–165 contains a cysteine at position 165, we sought to address
whether modification of cysteine 165 would reduce the immunogenicity of
the peptide NY-ESO-1 157–165. CTL recognition of different doses of
the peptide NY-ESO-1 157–165 was analyzed in the presence or absence
of 200 µM of the reducing agents DTT and TCEP (Fig. 3 and data not shown). The results of
these experiments demonstrated that the presence of reducing agents
increased by 10-fold the antigenicity of the peptide NY-ESO-1 157–165,
while no effect was observed for the recognition of different peptides
lacking cysteine residues (Fig. 3 and data not shown). These results
are consistent with previous published data (9), and
suggest that a modification of the cysteine 165 in the NY-ESO-1 peptide
157–165 may result in a reduced recognition by specific CTL.
Stabilization of HLA-A2 molecules expressed on the surface of T2 cells
by different concentrations of the NY-ESO-1 157–165 peptide
(13) revealed that this peptide has a low binding
affinity, as compared with the binding affinity of the influenza matrix
peptide 58–66 (Fig. 4, B and
C). Binding of the NY-ESO-1 157–165 peptide to HLA-A2
molecules did not significantly change in the presence and absence of
200 µM TCEP (data not shown). It is worth noting that, despite the
low binding affinity of peptide NY-ESO-1 157–165, HLA-A2 tetramers
containing this peptide were stable and capable of staining
NY-ESO-1-specific CTL (4) (Figs. 1
A and
5).
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). Two distinct approaches were followed. First,
9-mer peptide NY-ESO-1 157–165 was synthesized with cysteine 165
replaced by the stronger HLA-A2 anchor residue amino acids
(16) valine, isoleucine, and leucine. Second, 10-mer
peptides were synthesized containing at the carboxyl terminus anchor
residue amino acids, more often observed at the carboxyl terminus of
HLA-A2-binding peptides (16). Cysteine 165, at position 9
of these peptides, was either conserved (NY-ESO-1 157–166 (CV),
NY-ESO-1 157–166 (CI)), or substituted for an alanine (NY-ESO-1
157–166 (AL), NY-ESO-1 157–166 (AI), NY-ESO-1 157–166 (AF)). In
addition, peptide NY-ESO-1 157–165 was synthesized containing the SH
group of cysteine 165 blocked by a -NH-CO-CH2
side chain. While recognition of the latter peptide was not
significantly better than the wild-type peptide 157–165 (data not
shown), substitution of cysteine 165 with either valine (NY-ESO-1
157–165 (V)), isoleucine (NY-ESO-1 157–165 (I)), or leucine (NY-ESO-1
157–165 (L)) increased by at least 100-fold recognition by NY-ESO-1
157–165-specific CTL, as compared with the recognition of NY-ESO-1
157–165 (Fig. 4A). In contrast, 10-mer peptide analogues,
with the exception of peptide NY-ESO-1 157–166 (CV), were not
recognized more efficiently than the wild-type peptide NY-ESO-1
157–165 (Fig. 4A). Addition of TCEP to peptide NY-ESO-1
157–165 (V) did not increase the percentage of specific lysis, while
TCEP increased by 10-fold recognition of wild-type peptide NY-ESO-1
157–165 (Fig. 3).
The increased recognition of peptides NY-ESO-1 157–165 (V), NY-ESO-1
157–165 (I), and NY-ESO-1 157–165 (L) can be accounted for by a
combination of higher peptide-binding affinity to HLA-A2 molecules and
TCR. Binding of peptide analogues to HLA-A2 molecules was compared with
the binding of the wild-type peptide NY-ESO-1 157–165. Peptides
NY-ESO-1 157–165 (V) and NY-ESO-1 157–165 (I) were capable of
stabilizing HLA-A2 molecules more efficiently than the wild-type
peptide NY-ESO-1 157–165 (Fig. 4B). These results were
further confirmed by measuring peptide binding to metabolically labeled
HLA-A2 molecules in T2 cells (as first described in Ref.
13) (Fig. 4C). Addition of TCEP during the
assay did not increase surface expression of HLA-A2 molecules, while
there was a small shift for peptide NY-ESO-1 157–166 (CI) (data not
shown).
Stimulation of NY-ESO-1-specific CTL from melanoma patients’ PBL
To study the ability of different peptide analogues to stimulate
proliferation of NY-ESO-1-specific CTL, PBL from two melanoma patients
with a high titer of NY-ESO-1 specific Abs were stimulated with
different doses of wild-type peptide NY-ESO-1 157–165 and peptide
NY-ESO-1 157–165 (V). To minimize the effect of modification of the
cysteine 165 contained in the peptide NY-ESO-1 157–165, PBL were
maintained either in the presence or absence of 200 µM TCEP.
Stimulation of PBL samples with peptide NY-ESO-1 157–165 (V) in the
presence of reducing agents resulted in a 14-fold greater expansion of
NY-ESO-1-specific CTL over 2 wk, and 54-fold expansion over 3 wk (Fig. 5), as compared with CTL expansion driven by the wild-type peptide
NY-ESO-1 157–165. Similar results were obtained after stimulating PBL
in the absence of reducing agents (data not shown). Specific CTL were
stained with HLA-A2 tetramers containing the NY-ESO-1 157–165 peptide,
hence demonstrating the ability of these cells to recognize the
wild-type peptide NY-ESO-1 157–165. A dose of 10 nM of peptide
NY-ESO-1 157–165 (V) was capable of stimulating expansion of
NY-ESO-1-specific CTL, while identical doses of the wild-type peptide
NY-ESO-1 157–165 failed to expand NY-ESO-1-specific CTL. These results
confirmed the enhanced immunogenicity of the peptide analogue NY-ESO-1
157–165 (V).
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Discussion |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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40–50% of melanoma patients with advanced tumors expressing
NY-ESO-1 make a simultaneous Ab and CTL response against NY-ESO-1
(4), hence demonstrating that NY-ESO-1 is to date the only
cancer-testis Ag capable of eliciting both a humoral and cellular
response in a large proportion of patients. However, it remained to be
established how efficiently tumor cells are capable of presenting
NY-ESO-1-derived peptides to NY-ESO-1-specific CTL, and whether
antigenicity of NY-ESO-1 synthetic peptides can be increased by
substituting amino acid residues that do not impair TCR recognition. To
address these questions, we generated NY-ESO-1-specific CTL clones
using HLA-A2 tetramers containing the peptide NY-ESO-1 157–165.
In the first part of this work, we showed that NY-ESO-1 can be
efficiently processed by melanoma cells and recognized by NY-ESO-1
157–165-specific CTL clones (Fig. 1B). These results
confirm previously published data (5) and extend them by
further defining the processing pathway responsible for the
presentation of the NY-ESO-1/HLA-A2 epitope. Although the nature of the
naturally processed NY-ESO-1/HLA-A2 peptide remains to be determined,
we demonstrated in this study that peptides NY ESO-1 157–165, NY-ESO-1
157–166, and NY-ESO-1 157–167 are recognized by clonal CTL, while
peptide NY-ESO-1 157–164 was not seen (Fig. 1C). These
results provide insights into the definition of the minimal-length
NY-ESO-1 HLA-A2 peptide presented by tumor cells. Since peptide
NY-ESO-1 155–163 was not recognized (Fig. 4A), while
peptide NY-ESO-1 157–165 was efficiently seen, our results are
consistent with the possibility that glutamine 164 and cysteine 165 of
the peptide NY-ESO-1 157–165 contribute to the antigenicity of the
peptide NY-ESO-1 157–165. This conclusion is supported by the findings
that some NY-ESO-1 peptide analogues, in which cysteine 165 was
substituted for certain amino acids, were more antigenic than the
peptide NY-ESO-1 157–165.
The observation that certain viral epitopes are not generated in cells
lacking the IFN-
-inducible proteasome subunits LMP2 and LMP7 raises
the question of whether the generation of certain melanoma epitopes can
be impaired by a down-regulation of LMP2 and LMP7 (12, 13, 14, 17, 18). As these proteasome subunits are not required for cell
viability, it is to be expected that a strong CTL response will select
for melanoma cells with mutations or deletion of LMPs, resulting in a
functional deficiency of the Ag-processing pathway. Indeed, human
spontaneous lung carcinoma cell lines with down-regulation of LMPs have
been described (19). A recent report has suggested that
dendritic cells may fail to generate defined tumor CTL epitopes, as a
result of their destruction by LMP-positive proteasomes
(7). This reasoning led us to study the role of LMP gene
products and proteasome proteolytic activity for the generation of the
NY-ESO-1 epitope 157–165. Our results demonstrate that presentation of
NY-ESO-1/HLA-A2 epitope is not dependent on the presence of LMP2 and
LMP7, as we showed efficient lysis of LMP-positive and LMP-negative
cells by NY-ESO-1 157–165-specific CTL after infection with NY-ESO-1
vaccinia virus. These results were controlled for by analyzing
simultaneously presentation of the LMP7-dependent influenza matrix
HLA-A2 epitope (Fig. 2, A and B).
In the second part of these studies, we analyzed whether antigenicity
of the peptide NY-ESO-1 157–165 was enhanced by modifying the
peptide’s carboxyl-terminal amino acid. As peptide 157–165 has a
cysteine at position 9, we reasoned that its sulfhydryl modification
could reduce its binding affinity and antigenicity. Our results were
consistent with this possibility, as we showed that target cells pulsed
with peptide NY-ESO-1 157–165 in the presence of reducing agents were
recognized 10 times more efficiently (Fig. 3). These findings are in
line with previously published data, demonstrating that modification of
cysteine residues affects the immunogenicity of MHC class I viral
determinants (9).
We then identified a series of NY-ESO-1 peptide analogues with greater
antigenicity than the wild-type peptide. In particular, we showed that
peptide analogues with cysteine 165 substituted by either a valine,
isoleucine, or leucine were recognized at least 100 times more
efficiently than the wild-type peptides (Fig. 4A). Binding
of peptide NY-ESO-1 157–165 (V), NY-ESO-1 157–165 (I), and NY-ESO-1
157–165 (L) to HLA-A2 molecules was more efficient than the wild-type
peptide NY-ESO-1 157–165. However, it is worth noting that HLA-A2
tetramers containing either the wild-type peptide NY-ESO-1 157–165 or
peptide NY-ESO-1 157–165 (I) gave similar intensity of staining of the
NY-ESO-1-specific CTL clone (data not shown).
Finally, we studied the immunogenicity of NY-ESO-1 peptide analogues using PBL from melanoma patients. The peptide NY-ESO-1 157–165 (V) was capable of inducing a significantly more efficient expansion of NY-ESO-1-specific CTL from patients’ PBL, as compared with wild-type peptide NY-ESO-1 157–165 in the presence or absence of reducing agents. The specificity of peptide NY-ESO-1 157–165 (V)-expanded CTL was confirmed by their ability to be stained with HLA-A2 tetramers containing the wild-type peptide NY-ESO-1 157–165. Over a 2-wk restimulation, the frequency of NY-ESO-1-specific CTL was more than 50 times greater in cultures expanded in the presence of the peptide analogue NY-ESO-1 157–165 (V). Increased antigenicity and immunogenicity of NY-ESO-1 peptide analogues may result from a combination of their higher binding affinity to HLA-A2 molecules and better interaction with TCRs of specific CTL clones and lines. The relationship between Ag presentation, peptide-binding affinity, and expansion of CTL in vitro and in vivo is still unclear. Results obtained with different Listeria monocytogenes mutants showed that the extent of T cell priming and expansion is not related in a linear fashion to the amount of presented epitope (20). It has been shown, however, that recombinant vaccinia virus encoding HLA-A2/Melan-A epitope 27–35 analogues can prime more efficiently HLA-A2 transgenic mice than vaccinia encoding wild-type Melan-A peptide (21, 22).
In conclusion, we have demonstrated that processing of NY-ESO-1 protein by tumor cells results in the generation of an A2-restricted CTL epitope. Since specific killing of NY-ESO-1-positive tumor cells was shown using tetramer-sorted NY-ESO-1-specific CTL clones, our results definitively prove that the NY-ESO-1 epitope 157–165 is generated by tumor cells, hence emphasizing the importance of this epitope in cancer vaccines. We have defined the minimal overlapping peptide region required for the recognition of this epitope and demonstrated that its presentation is not dependent on the presence of immunoproteasome. Finally, we extended these results by identifying peptide analogues capable of an enhanced stimulation of NY-ESO-1-specific CTL from melanoma patients’ PBL. Since NY-ESO-1 is expressed in 20–40% of several common tumor types and HLA-A2 is expressed in 40% of Caucasian population, our findings confirm the importance of vaccines capable of expanding NY-ESO-1-specific CTL in cancer patients. Phase 1 clinical trials using NY-ESO-1 synthetic peptides are already in progress aimed at eliciting a tumor-specific CTL response. The use of peptide analogues could result in a more efficient induction of NY-ESO-1-specific CTL in cancer patients.
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Acknowledgments |
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Footnotes |
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2 Address correspondence and reprint requests to Dr. Vincenzo Cerundolo, Institute of Molecular Medicine, John Radcliffe Hospital, OX3 9DS, Oxford, U.K.
3 Abbreviations used in this paper: SEREX, serological analysis of recombinant cDNA expression libraries; ß2m, ß2-microglobulin; LMP, low molecular protein; TCEP, tris(2-carboxyethyl)phosphine hydrochloride.
Received for publication February 16, 2000. Accepted for publication May 8, 2000.
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References |
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exposes a cryptic cytotoxic T lymphocyte epitope in HIV-1 reverse transcriptase. J. Immunol. 162:7075.This article has been cited by other articles:
|
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|
  D. E. Speiser, P. Baumgaertner, V. Voelter, E. Devevre, C. Barbey, N. Rufer, and P. Romero Unmodified self antigen triggers human CD8 T cells with stronger tumor reactivity than altered antigen PNAS, March 11, 2008; 105(10): 3849 - 3854. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Qian, J. Xie, S. Hong, J. Yang, L. Zhang, X. Han, M. Wang, F. Zhan, J. D. Shaughnessy Jr, J. Epstein, et al. Dickkopf-1 (DKK1) is a widely expressed and potent tumor-associated antigen in multiple myeloma Blood, September 1, 2007; 110(5): 1587 - 1594. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. Sabbatini and K. Odunsi Immunologic Approaches to Ovarian Cancer Treatment J. Clin. Oncol., July 10, 2007; 25(20): 2884 - 2893. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. A. Purbhoo, Y. Li, D. H. Sutton, J. E. Brewer, E. Gostick, G. Bossi, B. Laugel, R. Moysey, E. Baston, N. Liddy, et al. The HLA A*0201-restricted hTERT540-548 peptide is not detected on tumor cells by a CTL clone or a high-affinity T-cell receptor Mol. Cancer Ther., July 1, 2007; 6(7): 2081 - 2091. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K.-L. Ling, N. Dulphy, P. Bahl, M. Salio, K. Maskell, J. Piris, B. F. Warren, B. D. George, N. J. Mortensen, and V. Cerundolo Modulation of CD103 Expression on Human Colon Carcinoma-Specific CTL J. Immunol., March 1, 2007; 178(5): 2908 - 2915. [Abstract] [Full Text] [PDF]
|
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|
K. M. Zirlik, D. Zahrieh, D. Neuberg, and J. G. Gribben Cytotoxic T cells generated against heteroclitic peptides kill primary tumor cells independent of the binding affinity of the native tumor antigen peptide Blood, December 1, 2006; 108(12): 3865 - 3870. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. A. Purbhoo, D. H. Sutton, J. E. Brewer, R. E. Mullings, M. E. Hill, T. M. Mahon, J. Karbach, E. Jager, B. J. Cameron, N. Lissin, et al. Quantifying and Imaging NY-ESO-1/LAGE-1-Derived Epitopes on Tumor Cells Using High Affinity T Cell Receptors. J. Immunol., June 15, 2006; 176(12): 7308 - 7316. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Eguchi, M. Hatano, F. Nishimura, X. Zhu, J. E. Dusak, H. Sato, I. F. Pollack, W. J. Storkus, and H. Okada Identification of Interleukin-13 Receptor {alpha}2 Peptide Analogues Capable of Inducing Improved Antiglioma CTL Responses Cancer Res., June 1, 2006; 66(11): 5883 - 5891. [Abstract] [Full Text] [PDF]
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F. van Rhee, S. M. Szmania, F. Zhan, S. K. Gupta, M. Pomtree, P. Lin, R. B. Batchu, A. Moreno, G. Spagnoli, J. Shaughnessy, et al. NY-ESO-1 is highly expressed in poor-prognosis multiple myeloma and induces spontaneous humoral and cellular immune responses Blood, May 15, 2005; 105(10): 3939 - 3944. [Abstract] [Full Text] [PDF]
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 |
|
 J.-L. Chen, G. Stewart-Jones, G. Bossi, N. M. Lissin, L. Wooldridge, E. M. L. Choi, G. Held, P. R. Dunbar, R. M. Esnouf, M. Sami, et al. Structural and kinetic basis for heightened immunogenicity of T cell vaccines J. Exp. Med., April 18, 2005; 201(8): 1243 - 1255. [Abstract] [Full Text] [PDF]
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K. Ida, S. Kawaguchi, Y. Sato, T. Tsukahara, Y. Nabeta, H. Sahara, H. Ikeda, T. Torigoe, S. Ichimiya, K. Kamiguchi, et al. Crisscross CTL Induction by SYT-SSX Junction Peptide and Its HLA-A*2402 Anchor Substitute J. Immunol., July 15, 2004; 173(2): 1436 - 1443. [Abstract] [Full Text] [PDF]
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 |
|
 A. I. Webb, M. A. Dunstone, W. Chen, M.-I. Aguilar, Q. Chen, H. Jackson, L. Chang, L. Kjer-Nielsen, T. Beddoe, J. McCluskey, et al. Functional and Structural Characteristics of NY-ESO-1-related HLA A2-restricted Epitopes and the Design of a Novel Immunogenic Analogue J. Biol. Chem., May 28, 2004; 279(22): 23438 - 23446. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Sugita, H. Wada, S. Fujita, T. Nakata, S. Sato, Y. Noguchi, A. A. Jungbluth, M. Yamaguchi, Y.-T. Chen, E. Stockert, et al. NY-ESO-1 Expression and Immunogenicity in Malignant and Benign Breast Tumors Cancer Res., March 15, 2004; 64(6): 2199 - 2204. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. J. Palmowski, L. Lopes, Y. Ikeda, M. Salio, V. Cerundolo, and M. K. Collins Intravenous Injection of a Lentiviral Vector Encoding NY-ESO-1 Induces an Effective CTL Response J. Immunol., February 1, 2004; 172(3): 1582 - 1587. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. M.-L. Choi, J.-L. Chen, L. Wooldridge, M. Salio, A. Lissina, N. Lissin, I. F. Hermans, J. D. Silk, F. Mirza, M. J. Palmowski, et al. High Avidity Antigen-Specific CTL Identified by CD8-Independent Tetramer Staining J. Immunol., November 15, 2003; 171(10): 5116 - 5123. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. M. Boulter, M. Glick, P. T. Todorov, E. Baston, M. Sami, P. Rizkallah, and B. K. Jakobsen Stable, soluble T-cell receptor molecules for crystallization and therapeutics Protein Eng. Des. Sel., September 1, 2003; 16(9): 707 - 711. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 I. D. Davis, M. Jefford, P. Parente, and J. Cebon Rational approaches to human cancer immunotherapy J. Leukoc. Biol., January 1, 2003; 73(1): 3 - 29. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. Huarte, P. Sarobe, J. Lu, N. Casares, J. J. Lasarte, J. Dotor, M. Ruiz, J. Prieto, E. Celis, and F. Borras-Cuesta Enhancing Immunogenicity of a CTL Epitope from Carcinoembryonic Antigen by Selective Amino Acid Replacements Clin. Cancer Res., July 1, 2002; 8(7): 2336 - 2344. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Parmiani, C. Castelli, P. Dalerba, R. Mortarini, L. Rivoltini, F. M. Marincola, and A. Anichini Cancer Immunotherapy With Peptide-Based Vaccines: What Have We Achieved? Where Are We Going? J Natl Cancer Inst, June 5, 2002; 94(11): 805 - 818. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. S. Schultz, J. Chapiro, C. Lurquin, S. Claverol, O. Burlet-Schiltz, G. Warnier, V. Russo, S. Morel, F. Levy, T. Boon, et al. The Production of a New MAGE-3 Peptide Presented to Cytolytic T Lymphocytes by HLA-B40 Requires the Immunoproteasome J. Exp. Med., February 11, 2002; 195(4): 391 - 399. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Terasawa, K.-Y. Tsang, J. Gulley, P. Arlen, and J. Schlom Identification and Characterization of a Human Agonist Cytotoxic T-Lymphocyte Epitope of Human Prostate-specific Antigen Clin. Cancer Res., January 1, 2002; 8(1): 41 - 53. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J.-n. Cao, T.-w. Gao, E. J. Stanbridge, and R. Irie RBP1L1, a Retinoblastoma-Binding Protein-Related Gene Encoding an Antigenic Epitope Abundantly Expressed in Human Carcinomas and Normal Testis J Natl Cancer Inst, August 1, 2001; 93(15): 1159 - 1165. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Gnjatic, Y. Nagata, E. Jager, E. Stockert, S. Shankara, B. L. Roberts, G. P. Mazzara, S. Y. Lee, P. R. Dunbar, B. Dupont, et al. Strategy for monitoring T cell responses to NY-ESO-1 in patients with any HLA class I allele PNAS, September 26, 2000; 97(20): 10917 - 10922. [Abstract] [Full Text] [PDF]
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), NY-ESO-1 157–166 (
), NY-ESO-1 157–167
(•), NY-ESO-1 157–164 (
), and Flu matrix 58–66 (
). SD values
at each peptide concentration were added in the figure. These results
were confirmed in three separate experiments.
). The results of these
experiments were confirmed in three separate experiments.
B, CTL clone specific for either the NY-ESO-1 157–165
epitope (top panel) or influenza matrix epitope 58–66
(bottom panel) was used against .174 transfected with
TAP1 and TAP2 (.174/TAPs) and the parental line .45. The target cells
.174/TAPs were treated (triangles) or mock treated (squares) with
lactacystin. The results of these experiments were confirmed in two
separate experiments.
), 1 nM (
), and no
peptide (
). y-axis shows density of HLA-A2 heavy
chain bands.