The JI
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
 QUICK SEARCH:   [advanced]


     
 


This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Anichini, A.
Right arrow Articles by Mortarini, R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Anichini, A.
Right arrow Articles by Mortarini, R.
Right arrowPubmed/NCBI databases
*Substance via MeSH
Medline Plus Health Information
*Melanoma
The Journal of Immunology, 2003, 171: 2134-2141.
Copyright © 2003 by The American Association of Immunologists

Differentiation of CD8+ T Cells from Tumor-Invaded and Tumor-Free Lymph Nodes of Melanoma Patients: Role of Common {gamma}-Chain Cytokines1

Andrea Anichini2,*, Alessia Scarito*, Alessandra Molla*, Giorgio Parmiani{dagger} and Roberta Mortarini*

* Human Tumor Immunobiology and {dagger} Tumor Immunotherapy Units, Department of Experimental Oncology, Istituto Nazionale per lo Studio e la Cura dei Tumori, Milan, Italy


    Abstract
 Top
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
 References
 
Differentiation of CD8+ T cells at the tumor site toward effector and memory stages may represent a key step for the efficacy of antitumor response developing naturally or induced through immunotherapy. To address this issue, CD8+ T lymphocytes from tumor-invaded (n = 142) and tumor-free (n = 42) lymph nodes removed from the same nodal basin of melanoma patients were analyzed for the expression of CCR7, CD45RA, perforin, and granzyme B. By hierarchical cluster analysis, CD8+ T cells from all tumor-free lymph nodes and from 56% of the tumor-invaded lymph node samples fell in the same cluster, characterized mainly by CCR7+ CD45RA+/- cytotoxic factor- cells. The remaining three clusters contained only samples from tumor-invaded lymph nodes and showed a progressive shift of the CD8+ T cell population toward CCR7- CD45RA-/+ perforin+ granzyme B+ differentiation stages. Distinct CD8+ T cell maturation stages, as defined by CCR7 vs CD45RA and by functional assays, were identified even in melanoma- or viral Ag-specific T cells from invaded lymph nodes by HLA tetramer analysis. Culture for 7 days of CCR7+ perforin- CD8+ T cells from tumor-invaded lymph nodes with IL-2 or IL-15, but not IL-7, promoted, mainly in CCR7+CD45RA- cells, proliferation coupled to differentiation to the CCR7- perforin+ stage and acquisition of melanoma Ag-specific effector functions. Taken together, these results indicate that CD8+ T cells differentiated toward CCR7- cytotoxic factor+ stages are present in tumor-invaded, but not in tumor-free, lymph nodes of a relevant fraction of melanoma patients and suggest that cytokines such as IL-2 and IL-15 may be exploited to promote Ag-independent maturation of anti-tumor CD8+ T cells.


    Introduction
 Top
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
 References
 
The definitions of functional status and of Ag-induced differentiation stage of T cells at tumor site are among the main goals for understanding how T cell-mediated antitumor immunity is regulated in cancer patients during tumor progression or after immunotherapy (1, 2, 3). For many years these challenges have relied on assessing the frequency and Ag-specific functions of T cells isolated from neoplastic lesions (4). More recently, new markers of T cell differentiation have been identified (5, 6, 7, 8, 9) and a few models of Ag-induced post-thymic development of human CD4+ and CD8+ T cells have been proposed by analysis of peripheral blood T cell response to viral Ags (6, 7, 8, 9). Within the CD8+ T cell fraction, the models of human T cell differentiation rely on the identification of distinct T cell subsets depending on the expression of leukocyte common Ag isoforms (CD45RA and RO), chemokine receptors (such as CCR4, CCR5, CCR6, and CCR7), costimulatory molecules (such as CD27 and CD28), L-selectins (CD62L), and cytotoxic factors (such as perforin and granzymes) and on functional evaluation of Ag-specific responses (6, 7, 8, 9, 10, 11).

The available models are not fully concordant on the phenotypic and functional signatures that identify each T cell differentiation stage (7, 8, 9). Nevertheless, in all models Ag-induced CD8+ T cell maturation is seen as a linear sequence from the CCR7+ CD45RA+ naive (TN)3 stage to the Ag-experienced CCR7+ CD45RA- central memory (TCM), and CCR7- CD45RA- effector memory (TEM) cells and to the CCR7- CD45RA+ stage, defined either as terminally differentiated cells (7) or, more recently (11), as TEMRA (CD45RA+ effector memory cells). Furthermore, emerging evidence, obtained in both the human system and murine models, indicates that each step along the differentiation pathway is part of a continuum, rather than representing distinct cell subsets, and some of the stages may be reversible and affected differently by Ag or cytokines sharing the common cytokine receptor {gamma}-chain ({gamma}c) (7, 10, 11, 12).

A few studies have addressed the issue of antitumor CD8+ T cell differentiation in melanoma patients by adopting the existing models of post-thymic CD8+ T cell development. In some patients, not subjected to immunotherapy, tumor-specific T cells with a CCR7- CD45RA- TEM phenotype (13) or a CCR7- CD45RA+ effector phenotype (14) have been described in the periphery or in a few cases of invaded lymph nodes, and these cells expressed Ag-specific effector functions such as IFN-{gamma} release and direct ex vivo lytic activity without activation. In vaccinated patients, differentiation to the CCR7- and/or CD27- stages on CD8+ tumor-specific T cells in peripheral blood has been described after therapy (15, 16, 17), although these cells in some instances did not express cytotoxic factors and required Ag exposure for functional reactivation.

However, despite this evidence, it remains to be elucidated, at the population level, whether T cell differentiation is promoted at the tumor site as a result of the natural evolution of immunity to the disease compared with a tumor-free tissue. The surgical treatment of American Joint Committee on Cancer (AJCC) (18) stage III melanoma patients can provide ideal test and control tissue samples to address the question of T cell differentiation at the tumor site. In fact, in several patients both tumor-invaded (TILN) and tumor-free (TFLN) lymph nodes are isolated from the same nodal basin. Moreover, the issue of T cell differentiation at the tumor site is relevant not only for a better understanding of the natural evolution of tumor immunity, but to designing improved protocols of immunotherapy. This goal is being pursued through Ag-specific vaccination, an approach that may promote activation of T cells directed to a few different melanoma Ags (1). Nevertheless, the identification of efficient means to promote Ag-independent differentiation of CD8+ T cells would further expand the repertoire of tumor-specific T lymphocytes that could be turned into effector cells.

These issues were addressed by investigating the differentiation profile and the response to cytokines of CD8+ T cells in a large panel of TILN and TFLN from stage III melanoma patients. Here we show that a considerable fraction of TILN display a CD8+ T cell phenotypic profile characterized by increasing content of lymphocytes at the CCR7- cytotoxic factor+ stage, a phenotype not found in CD8+ T cells from most TFLN. Furthermore, in patients whose invaded lymph nodes contained a predominant fraction of CD8+ T cells in early maturation stages (i.e., CCR7+ CD45RA+/- cytotoxic factor-), we show that cytokines such as IL-2 and IL-15 can promote Ag-independent differentiation of a fraction of CD8+ T cells associated with the acquisition of tumor Ag-specific effector functions.


    Materials and Methods
 Top
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
 References
 
Patients and donors

Informed consent was obtained from the patients. Lymphocytes were isolated from TILN of 142 melanoma patients in AJCC stage III as previously described (19). In 42 of these patients lymphocytes were also isolated from TFLN removed from the same nodal basin as TILN. The presence or the absence of metastatic melanoma cells in the lymph node samples was assessed by conventional histochemistry on serial tissue sections and was confirmed by flow cytometry with mAbs to high m.w. melanoma Ags (20). All metastases found in TILN were of the massive type. HLA-A*0201 subtyping was performed by PCR-sequence-specific oligonucleotide probe typing as previously described (19). None of the patients enrolled in this study had been subjected to chemotherapy, immunotherapy, or any other therapy with immunosuppressive activity before isolation of lymphocytes.

Flow cytometric analysis

Different combinations of the following mouse anti-human mAbs were used: anti-CD8 coupled to PerCP or allophycocyanin, FITC- or PE-anti-CD45RA, and PerCP- or PE-anti-CD3 (BD PharMingen, San Diego, CA). To detect CCR7, cells were stained with IgM anti-CCR7 (BD PharMingen), followed by biotin-conjugated rat anti-mouse IgM and then by CyChrome-conjugated streptavidin (BD PharMingen). To detect intracellular perforin or granzyme B, cells were permeabilized with Cytofix/Cytoperm (BD PharMingen) and then stained with FITC anti-perforin (BD PharMingen) or PE-anti-granzyme B (CLB, Amsterdam, The Netherlands) in the presence of Perm/Wash solution (BD PharMingen). In some experiments CCR7+ lymphocytes from TILN and PBL were purified by cell sorting after staining with anti-CCR7 mAb. Sorting, acquisition, and analysis by four-color flow cytometry were conducted by a dual-laser FACSCalibur cytofluorometer (BD Biosciences, Mountain View, CA) using CellQuest software. PE-labeled tetramers of HLA-A*0201-containing peptides from Melan-A/Mart-126–35 (21, 22), gp100209–217 (23), MAGE-3271–279 (24), NY-ESO-1157–165 (25), and influenza matrix58–66 peptides (26) were purchased from ProImmune (Oxford, U.K.). Tetramers were titrated against peptide-specific T cell lines to minimize background staining while preserving the mean fluorescence intensity of positive cells and then were used at a final dilution of 1/200 of the stock solution. Cells (2 x 106) were stained for 15 min with PE-labeled tetramers at 37°C and then stained for 30 min on ice with other cell surface Abs. Negative controls for tetramer staining included PBL from HLA-A*0201- healthy controls.

Intracellular IFN-{gamma} detection

Lymphocytes from peripheral blood, TILN, or short term T cell cultures were stained with PE-tetramers for 15 min at 37°C and then stimulated in the presence of autologous PBMC loaded with 2 µM Melan-A/Mart-127–35 or gp100209–217 peptides for 4–6 h. After the first hour, GolgiStop (BD PharMingen) was added. Cell surface staining was then conducted with PerCP-anti-CD8 and/or CyChrome-anti-CCR7, followed by cell permeabilization with Cytofix/Cytoperm and staining with allophycocyanin-anti-IFN-{gamma} mAb in the presence of Perm/Wash solution. The expression of IFN-{gamma} was then analyzed by flow cytometry after imposing a double gating for CD8+ and tetramer+ T cells (7).

CD69 up-regulation

Lymphocytes from peripheral blood or TILN were cultured with 20 ng/ml PMA (Sigma-Aldrich, St. Louis, MO) and 500 ng/ml ionomycin (Sigma-Aldrich) for 5 h. Cells were then stained with allophycocyanin-anti-CD8, PE-anti-CD45RA, CyChrome-anti-CCR7, and FITC-anti-CD69 Abs (BD PharMingen) and analyzed by flow cytometry. Alternatively, PMA- plus ionomycin-stimulated lymphocytes were analyzed for intracellular IFN-{gamma} production by staining with PE-anti-CD8, CyChrome-anti-CCR7, FITC-anti-CD45RA, and allophycocyanin-anti-IFN-{gamma} Abs after permeabilization.

Cytokines and CFSE proliferation assay

Lymphocytes from TILN were cultured at 1 x 106/ml in RPMI 1640 containing 10% pooled human serum in the presence of 50 ng/ml of IL-2 (Chiron, Emeryville, CA), IL-7 (PeproTech EC, London, U.K.), or IL-15 (PeproTech EC) for up to 7 days. To detect proliferating lymphocytes, cells were stained with 2 µM CFSE (Molecular Probes, Eugene, OR) for 10 min at 37°C, followed by three washes with cold RPMI 1640. CFSE-stained lymphocytes were then cultured in the presence of cytokines, or on plates precoated with anti-CD3 mAb (10 ng/ml) through cross-linking mediated by 10 µg/ml goat anti-mouse IgG (Sigma-Aldrich).

Cytotoxic assay

Lymphocytes from TILN were cultured at 1 x 106/ml in RPMI 1640 containing 10% pooled human serum with or without 50 ng/ml IL-2 (Chiron), IL-7 (PeproTech EC), or IL-15 (PeproTech EC). After 7 days the cytotoxic activity of these cultures was tested on Melan-A/Mart-1+, gp100+ HLA-A*0201+ melanomas, preincubated or not with anti-HLA-A2 mAb CR11.351 (27), and on T2 cells loaded with Melan-A/Mart-127–35 or gp100209–217 peptides. Lysis of targets was evaluated by a 4-h 51Cr release assay at E:T cell ratios from 20:1 to 2.5:1, as described previously (19).

Statistical analysis

Comparison of TILN and TFLN phenotypes for the proportion of CD3+ CD8+ T cells expressing each of the eight phenotypes defined by CCR7 vs CD45RA and by CCR7 vs perforin was evaluated by ANOVA, followed by Student-Newman-Keuls multiple comparison test. Hierarchical cluster analysis (28) of the CD3+ CD8+ T cell differentiation phenotype was conducted using J-Express Pro software (www.Molmine.com). Data were hierarchically clustered by tissue (TILN or TFLN) and phenotype using a complete linkage as clustering method and the Pearson correlation as the similarity measure.


    Results
 Top
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
 References
 
CD8+ T cell differentiation profile in TILN and TFLN from melanoma patients

CD3+ CD8+ T cells from TILN of 142 AJCC stage III melanoma patients were assessed for the expression of markers of differentiation. In addition, from 42 of such patients, a tissue sample of a TFLN, removed from the same nodal basin as the TILN, was obtained and analyzed. Hierarchical cluster analysis was performed to obtain a comprehensive classification of the CD8+ T cell phenotypic profiles of TILN and TFLN on the basis of the eight subsets defined by CCR7 vs CD45RA, and by CCR7 vs perforin. Four major CD8+ T cell phenotypic clusters were identified (Fig. 1). CD8+ T cells from all TFLN and 56% of the TILN samples fell into cluster 1, characterized by frequent CCR7+ CD45RA+ (TN) and CCR7+ CD45RA- (TCM) phenotypes or even CCR7- CD45RA- (TEM) cells, but lacking perforin in most instances or expressing it at very low levels and only in TILN samples, not in TFLN (Fig. 1). Increasing expression of perforin in the CCR7- subset characterized CD8+ T cells in clusters 2, 3, and 4, although not all CCR7- cells were perforin+, at either the TEM or TEMRA stage (see CCR7-/perforin- column in Fig. 1). These three clusters contained only T cells from TILN and showed a progressive increase in the proportion of CD8+ T cells at the CCR7- CD45RA- (TEM) and CCR7- CD45RA+ (TEMRA, or terminally differentiated) (7, 11) stages (Fig. 1). Significant differences in the differentiation profile between TILN and TFLN were confirmed by the Student-Newman-Keuls multiple comparison test for seven of eight phenotypic subsets defined by CCR7 vs CD45RA and CCR7 vs perforin (see Fig. 1). In agreement with these results, analysis of matched TILN and TFLN samples from the same patient indicated, in several instances, a shift of CD8+ T cells from TILN toward the CCR7- CD45RA- TEM stage, with expression of perforin in the CCR7- fraction, compared with the matched TFLN (representative results from seven patients shown in Fig. 2). Such differences between matched TILN and TFLN pairs were less pronounced when the TILN were isolated from patients in cluster 1, as in this instance both TILN and TFLN showed the early stages of differentiation (data not shown). Further evidence for differentiation of CD3+ CD8+ T cells, from a fraction of TILN, to cytotoxic factor+ stage was obtained by comparing CCR7 vs perforin and CCR7 vs granzyme B phenotypes. This analysis indicated that both cytotoxic factors were expressed in the CD8+ CCR7- T cells of TILN from the clusters 3 and 4 (Fig. 3), although, as seen for perforin, even granzyme B was not always expressed in all CCR7- cells (see CCR7-/granzyme B- column in Fig. 3).



View larger version (88K):
[in this window]
[in a new window]
 
FIGURE 1. Hierarchical cluster analysis of the differentiation phenotype of CD3+ CD8+ T cells in TILN and TFLN from AJCC stage III melanoma patients. Rows represent individual lymphocyte samples from TILN or TFLN; columns represent each of the eight possible phenotypes obtained by analysis of CCR7 vs CD45RA and of CCR7 vs perforin in CD3+ CD8+ lymphocytes by four-color flow cytometry. *, Tissue coding: black, TILN; white, TFLN. The four major clusters were ranked from 1–4 according to a progressive shift of the CD8+ T cell maturation profiles toward the CCR7- CD45RA+ perforin+ stage. The number of cases (percentage) from TILN or TFLN belonging to each phenotype cluster is shown on the right side. The percentage of positive cells for each phenotype subset was coded by 10 levels of gray shading, as indicated at the bottom of the figure. TILN and TFLN differed in the proportion of CD3+ CD8+ cells expressing the TN (p < 0.001), TCM (p < 0.001), TEM (p < 0.001), and TEMRA (p < 0.05) phenotypes as well as in the proportion expressing the CCR7+/perforin-, CCR7-/perforin-, and CCR7-/perforin+ phenotypes (p < 0.001 in all instances), while the CCR7+/perforin+ phenotype was not significantly different.

 


View larger version (22K):
[in this window]
[in a new window]
 
FIGURE 2. CD8+ T cells differentiation profile of matched TILN and TFLN samples from seven patients. TILN (•) and TFLN ({circ}) samples were evaluated for the expression of CCR7 vs CD45RA and CCR7 vs perforin in CD3+ CD8+ T cells by four-color flow cytometry. Results are expressed as the percentage of positive cells for each of the eight possible phenotypes. Statistical analysis was indicated as follows: *, p < 0.05; **, p < 0.01.

 


View larger version (54K):
[in this window]
[in a new window]
 
FIGURE 3. Analysis of perforin and granzyme B expression in CD3+CD8+ lymphocytes from TILN. Rows represent individual lymphocyte samples from TILN. Columns represent each of the eight possible phenotypes obtained by analysis of CCR7 vs perforin and of CCR7 vs granzyme B in gated CD3+ CD8+ lymphocytes. TILN belong to patients of differentiation clusters 1 and 3–4 as defined in Fig. 1. The percentage of positive cells for each of the indicated phenotypes was coded by 10 levels of gray shading, as indicated in Fig. 1.

 
In addition, comparison of PBL and TILN for the CD8+ T cell differentiation phenotype was performed in several patients belonging to the maturation clusters 1–4, but no relationship was found between PBL and TILN phenotypes (data not shown). Taken together these results indicate accumulation of CD8+ T cells at CCR7- cytotoxic factor+ stages in a large fraction of TILN, but not in TFLN, from metastatic melanoma patients.

Functional analysis of CD8+ T cell differentiation subsets from TILN

Lymphocytes from TILN in the panel of stage III patients were evaluated for CD69 up-regulation and cytokine secretion in response to PMA and ionomycin. All four CCR7/CD45RA subsets of CD8+ T lymphocytes from TILN (Fig. 4A) responded similarly in terms of CD69 up-regulation (Fig. 4B). In contrast, the CCR7+CD45RA+ TN subset did not produce IFN-{gamma} in response to PMA plus ionomycin (Fig. 4C), while this cytokine was mainly produced by CD8+ cells at the TCM and TEM stages (CCR7+CD45RA- and CCR7- CD45RA-) and to a lesser extent by TEMRA cells (CCR7- CD45RA+ subset; Fig. 4C). Furthermore, the proliferative response of CD8+ T cells from TILN to immobilized anti-CD3 mAb, as evaluated by CFSE staining, was found mainly in the CCR7+ CD45RA+ subset and to a lesser extent in the CCR7+ CD45RA- subset (Fig. 4D). These data indicate that the TILN CD8+ T cell differentiation subsets defined by CCR7 vs CD45RA expression are associated with distinct functional stages.



View larger version (24K):
[in this window]
[in a new window]
 
FIGURE 4. Functional analysis of CD8+ T cell subsets from TILN defined by their CCR7 vs CD45RA phenotype. CD8+ T cells from TILN, after staining for CD45RA and CCR7 (A), were evaluated for up-regulation of CD69 (B) and IFN-{gamma} production (C) in response to PMA plus ionomycin ({square}) compared with unstimulated cultures ({blacksquare}). The histograms show the response induced by PMA plus ionomycin in each of the four CD8+ subsets (identified as 1–4 in A–C) gated by the CCR7 vs the CD45RA phenotype. D, CFSE-stained lymphocytes from TILN were cultured on immobilized anti-CD3 mAb for 3 days. Gated CD8+ lymphocytes were analyzed for CFSE profiles according to their CCR7/CD45RA phenotype.

 
Differentiation profile of melanoma- and viral Ag-specific CD8+ T cells in TILN

The CCR7 vs CD45RA profile of melanoma-Ag-specific T cells recognized by HLA-A*0201 tetramers was investigated in HLA-A*0201 patients found in the panel of 142 TILN from stage III patients. The differentiation phenotype of tetramer+ T cells directed to melanocyte lineage Ags (Melan-A/Mart-126–35 and gp100209–217), tumor-restricted epitopes (Mage-3271–279 and NY-ESO-1157–165), or influenza matrix58–66 peptide, from TILN in cluster 1 (data from two representative patients in cluster 1 are shown in the upper two rows of panels in Fig. 5) indicated a predominant CCR7+ CD45RA+, TN phenotype, in agreement with the frequent profile of the bulk CD8+ T cell population. Evidence for progressive differentiation of tetramer+ T cells was obtained in TILN samples from patients in cluster 2, 3, and 4 (lower three rows of panels in Fig. 5). This was indicated by the increasing proportion of tetramer+ T cells expressing a TCM phenotype (as in the representative patient from cluster 2, Fig. 5) or expressing the TEM or TEMRA phenotype (see representative patients from clusters 3 and 4, respectively; Fig. 5). Interestingly, the pattern of differentiation of tetramer+ T cells directed to influenza matrix peptide was similar in each phenotype cluster to the phenotype of T cells directed to the four tumor Ags (Fig. 5). Analysis of TFLN samples from HLA-A*0201+ patients for the CCR7 vs CD45RA phenotype of CD8+ T cells directed to melanoma and influenza epitopes indicated a predominant TN or TCM phenotype, without expression of perforin (data not shown). Taken together, these data suggest that melanoma-specific and viral Ag-specific T cells from the same TILN or TFLN tissue sample may share a similar differentiation profile, in agreement with analysis at the bulk CD8+ T cell level.



View larger version (70K):
[in this window]
[in a new window]
 
FIGURE 5. Phenotype of Ag-specific CD8+ T cells from TILN of HLA-A*0201+ patients. Four-color flow cytometric analysis of the expression of CCR7 and CD45RA in the bulk CD8+ T cell population and in T cells identified by tetramers of HLA-A*0201-containing peptides from melanocyte lineage Ags (Melan-A/Mart-1 and gp100), tumor-restricted epitopes (MAGE-3 and NY-ESO-1), or influenza matrix. Patients belong to phenotype clusters 1–4 as defined in Fig. 1. Each row of six panels shows the phenotype of bulk CD8+ cells and tetramer+ T lymphocytes from TILN of one representative patient belonging to the indicated phenotype cluster. Numbers represent the percentage of positive cells in each quadrant.

 
IL-2 and IL-15 may promote differentiation of CD8+ CCR7+ T cells from TILN

The CD8+ T cell maturation profile of a large fraction of TILN samples in cluster 1 indicated a prevalence of CCR7+ CD45RA+, TN, or CCR7+ CD45RA-, TCM cells, lacking cytotoxic factors. To evaluate whether CD8+ T cells from cluster 1 could be induced through the differentiation process, CCR7+ T lymphocytes were sorted from TILN, labeled with CFSE, and then cultured with {gamma}c cytokines that may play a role in T cell differentiation (10, 11, 29). IL-2 and IL-15 induced a proliferative response in the sorted CCR7+ CD8+ T cells, while the response to IL-7 was minimal (Fig. 6A). Furthermore, while nonproliferating cells remained CCR7+, this marker was down-modulated in most CD8+ T lymphocytes that could proliferate to IL-2 and IL-15 (Fig. 6A). Sorted CCR7+ CD8+ T cells from PBL of healthy donors showed a similar response (Fig. 6B). In contrast to IL-2 and IL-15, the sorted CCR7+ CD8+ T cells from TILN did not down-modulate CCR7 when proliferating to immobilized anti-CD3 mAb (Fig. 6A). Analysis of CD45RA expression of the sorted CCR7+ CD8+ T cells from TILN confirmed the presence of two subsets, CD45RA+ (TN) and CD45RA- (TCM; Fig. 6C). In the CD8+ subset, proliferation to IL-2 or IL-15 was observed mainly in the CD45RA- fraction and to a lesser extent in the CD45RA+ fraction (Fig. 6C). By contrast, in the CD4+ subset the response to {gamma}c cytokines was mainly found in the CD45RA- subset (Fig. 6C). By gating for CCR7 and CD45RA on CFSE-labeled lymphocytes, the CD8+ T cells that proliferated to {gamma}c cytokines expressed, at the end of culture (day 7), either a CCR7- CD45RA- (TEM) or a CCR7-CD45RA+ (TEMRA) phenotype (data not shown). Further evidence for cytokine-induced CD8+ T cell differentiation was obtained in TILN from cluster 1 by looking at the expression of cytotoxic factors. Freshly isolated CD8+ T cells were mostly CCR7+ perforin- (Fig. 7). In contrast, after culture with IL-2, IL-15, or IL-2 plus IL-15, the CD3+ CD8+ lymphocytes expressed a predominant CCR7- perforin+ phenotype (Fig. 7). Culture with IL-7 led to up-regulation of perforin in a fraction of cells, but most of them remained CCR7+ (Fig. 7). Taken together these data indicate that differentiation of CCR7+ CD8+ T cells from TILN can be promoted in vitro by {gamma}c cytokines such as IL-2 and IL-15. This process involves mainly the proliferation of CCR7+ CD45RA- TCM cells and, to a lesser extent, of CCR7+ CD45RA+ TN cells, and leads to differentiation to CCR7- perforin+ stage.



View larger version (35K):
[in this window]
[in a new window]
 
FIGURE 6. Role of IL-2 and IL-15 in the differentiation of CD8+ T cells from TILN. Sorted CCR7+ lymphocytes from TILN of patients in cluster 1 (A and C) or from peripheral blood of a healthy donor (B) were stained with CFSE and then cultured for 7 days in medium alone or in the presence of IL-2, IL-7, IL-15, or immobilized anti-CD3 mAb and then analyzed for differentiation markers vs CFSE fluorescence. In each dot plot, right and left quadrants identify nonproliferating and proliferating cells, respectively.

 


View larger version (24K):
[in this window]
[in a new window]
 
FIGURE 7. Expression of CCR7 and perforin in freshly isolated TILN from a patient in cluster 1 and after culture for 7 days with {gamma}c cytokines. Dot plots were gated on CD3+ CD8+ cells. The numbers in the dot plots represent the percentage of positive cells in each quadrant.

 
Ag-independent differentiation of melanoma-specific T cells from TILN by {gamma}c cytokines

The impact of {gamma}c cytokines on T cell phenotype and function was evaluated in Melan-A/Mart-1- or gp100-specific T cells in TILN from HLA-A*0201+ patients in cluster 1. In these patients, freshly isolated tetramer+ T cells expressed mostly a CCR7+ CD45RA+ phenotype (Fig. 8), a phenotype that did not change by culture in medium without cytokines (data not shown). In contrast, after culture with IL-2, IL-15, or IL-2 plus IL-15, but not IL-7, tetramer+ T cells showed a CCR7- CD45RA+ phenotype in up to 50% of the cells (Fig. 8) or even a predominant CCR7- CD45RA- phenotype in some patients (data not shown).



View larger version (40K):
[in this window]
[in a new window]
 
FIGURE 8. Effect of {gamma}c cytokines on CCR7 vs CD45RA phenotype of melanoma-specific CD8+ T cells from TILN in cluster 1. Lymphocytes from TILN of an HLA-A*0201+ patient from cluster 1 were characterized for CCR7 vs CD45RA phenotype before (fresh TILN) and after culture for 7 days with IL-2, IL-7, IL-15, or IL-2 plus IL-15. The maturation phenotype was assessed in Ag-specific T cells recognized by HLA-A*0201/Melan-A/Mart-126–35 (1 ) and HLA-A*0201/gp100209–216 (2 ) tetramers. All dot plots were gated on CD8+ tetramer+ T cells. The numbers in the dot plots represent the percentage of positive cells in each quadrant.

 
At the functional level, intracellular expression of IFN-{gamma} in response to peptide-loaded APCs was observed by Melan-A/Mart-1-specific T cells after culture of lymphocytes from TILN with IL-2 and IL-15, but not with IL-7 or in freshly isolated cells (Fig. 9A). Similar results were obtained with gp100-specific T cells from TILN (see Fig. 9B for results on IL-2-cultured lymphocytes). However, while most of the tetramer+ T cells produced IFN-{gamma} when stimulated with PMA plus ionomycin (Fig. 9B), only a fraction of the cytokine-cultured tetramer+ T cells became positive for intracellular IFN-{gamma} in response to peptide-loaded APCs (Fig. 9, A and B). This was observed even in instances where most of the Ag-specific T lymphocytes were at the CCR7- stage after cytokine culture (Fig. 9B), suggesting heterogeneity for Ag-specific IFN-{gamma} production. Similar results, indicating production of IFN-{gamma} in response to peptide-loaded APCs after cytokine culture, were obtained even with flu matrix-specific T cells from TILN (data not shown).



View larger version (28K):
[in this window]
[in a new window]
 
FIGURE 9. Peptide-specific intracellular IFN-{gamma} production by CD8+ T cells from TILN after culture with {gamma}c cytokines. Lymphocytes from TILN of an HLA-A*0201+ patient in cluster 1 were cultured for 7 days with the indicated cytokines (A) or with IL-2 (B) and after staining with tetramers to Melan-A/Mart-1 (A) or gp100 (B) were evaluated for intracellular IFN-{gamma} production induced by autologous PBMC loaded (+peptide) or not (-peptide) with Melan-A/Mart-127–35 (A) or gp100209–217 (B). T cells in B were stimulated with peptide-loaded PBMCs or with PMA plus ionomycin and stained for CCR7.

 
Lymphocytes from TILN in cluster 1, after culture for 7 days with {gamma}c cytokines, were assessed for Ag-specific cytotoxicity. After culture with IL-2, IL-15, or IL-2 plus IL-15, the T cell cultures from TILN exhibited HLA-A2-restricted lysis of HLA-A*0201+, Melan-A/Mart-1+, gp100+ autologous melanoma (Fig. 10A) and lysed APCs loaded with Melan-A/Mart-1 peptide and, to a lesser extent, APCs loaded with gp100209–217 peptide (Fig. 10, C–E). By contrast, no lytic activity on melanoma cells (Fig. 10A), or on peptide-loaded APCs (Fig. 10B) was exerted by freshly isolated T cells from TILN. Taken together these results suggest that {gamma}c cytokines, such as IL-2 and IL-15, can promote in-vitro Ag-independent differentiation of melanoma-specific T cells from TILN.



View larger version (21K):
[in this window]
[in a new window]
 
FIGURE 10. Ag-specific cytotoxic activity by CD8+ T cells from TILN after culture with {gamma}c cytokines. TILN, either fresh or cultured for 7 days with the indicated cytokines, were assessed for: A, lysis of HLA-A*0201+ Melan-A/Mart-1+ gp100+ autologous melanoma pre-incubated (empty histograms) or not (black histograms) with anti-HLA-A2 mAb; B, lysis of T2 cells loaded with the indicated peptides; C–E, lysis of T2 cells either empty ({square}) or loaded with gp100209–217 ({blacktriangleup}) or Melan-A/Mart-127–35 (•) peptides.

 

    Discussion
 Top
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
 References
 
Comparison of TILN and TFLN from melanoma patients by hierarchical cluster analysis provided evidence for a marked shift of CD8+ T cell differentiation toward CCR7- cytotoxic factor+ stages at the tumor site in a relevant fraction of tissue samples. In fact, in three of four T cell phenotype clusters, representing ~44% of the TILN samples, we found that the differentiation profile of the CD8+ T cell fraction was gradually shifted toward an increasing content of CCR7- CD45RA-/+ cells containing the cytotoxic factors perforin and granzyme B. Thus, in these clusters, the CD8+ T cell differentiation was consistent with a progressive shift toward the TEM and TEMRA/terminally differentiated stages. The remaining TILN samples and all TFLN defined a single cluster in which CD8+ T cell differentiation was mainly characterized by CCR7+ CD45RA+, TN and CCR7+ CD45RA-, TCM stages. Moreover, most TILN and TFLN in this cluster lacked perforin or expressed it at very low levels and only in some TILN samples. The distinct CD8+ T cell subsets found in TILN and defined by intracellular and extracellular markers reflected distinct functional stages, as indicated by CFSE analysis for proliferative response to immobilized anti-CD3 mAb and by IFN-{gamma} release in response to PMA plus ionomycin. Taken together these results suggest that tumor-invaded, but not tumor-free, lymph nodes of a relevant fraction of stage III melanoma patients are involved in a process of CD8+ T cell differentiation beyond TN, TCM, and cytotoxic factor- stages.

Analysis of T cell maturation stages in melanoma-specific T cells from TILN indicated that the process of T cell differentiation could involve even tumor-specific T lymphocytes directed to melanocyte-lineage Ags or to tumor-restricted epitopes, as indicated by the phenotype of tetramer+ T cells from TILN of clusters 2–4. This may indicate a role of anti-tumor immunity in shaping the CD8+ T cell differentiation profile at the tumor site. However, interestingly, maturation along the TCM->TEM->TEMRA pathway was documented in the same TILN even for T cells directed to a viral epitope (influenza matrix). Such an effect may be promoted through Ag-independent bystander mechanisms (30, 31), and tumor-derived factors have a possible role in such process. In fact, some of the cytokines that can play a role in T cell differentiation, such as IL-15, can be produced by tumor cells, including melanoma (32). Moreover, other factors, such as IL-6 and IL-10, are frequently expressed by melanoma cells (33, 34). These factors could exert an indirect effect on T cell differentiation through their activity on the expression of IL-2/IL-15R{beta} and {gamma}-chains on T cells (10, 11), thus promoting the response of CD8+ T lymphocytes to soluble regulators of differentiation.

Culture of CCR7+ CD8+ lymphocytes from TILN of phenotypic cluster 1 in the presence of {gamma}c cytokines IL-2 and/or IL-15 promoted differentiation of a fraction of lymphocytes to the CCR7- perforin+ stage. This was associated with acquisition of Ag-specific effector functions, such as cytokine release and cytotoxicity. This cytokine-induced differentiation was restricted to a fraction of CD8+ lymphocytes that could proliferate in response to IL-2 and IL-15, suggesting differential expression of functional cytokine receptors in CCR7+ CD8+ T cells. Indeed, recent evidence indicates that IL-15R{alpha} and IL-2/IL-15R{beta}-chain expression is low, although detectable, in CCR7+ CD45RA+ TN cells and increases progressively along the TN->TCM->TEM differentiation pathway (10, 11), while {gamma}c is similarly expressed in the three stages (11). In agreement, analysis of the expression of differentiation markers indicated that the response of CCR7+ CD8+ T cells to {gamma}c cytokines was due mainly to proliferation of CD45RA- cells (i.e., TCM), with some response even in the CD45RA+ fraction (i.e., TN), and led to down-modulation of CCR7. Down-modulation of CCR7 after culture with {gamma}c cytokines is in agreement with the findings in the CD4+ subset (10), where the proliferative response has been shown to lead TCM (i.e., CCR7+ CD45RA-) cells to down-modulate CCR7 and acquire effector functions, such as cytokine release, associated with the CCR7- CD45RA- TEM stage. In the CD8+ subset, Geginat et al. (11) found that upon culture of PBL with IL-7 plus IL-15, TN cells maintained their phenotype, while the TCM fraction gave rise to cells expressing CCR7 and CD45RA in all possible combinations, including TEM and TEMRA. These latter phenotypes were the two profiles that we found expressed at the end of culture by CD8+ T cells that proliferated to IL-2 or IL-15, used as single cytokines. In addition, a direct comparison of IL-15 alone vs IL-7 plus IL-15 has not been performed, but it remains possible that CD8+ T cell maturation may be affected differently by culture with single {gamma}c cytokines, performed in our study, vs the combination of {gamma}c cytokines. Furthermore, we observed down-modulation of CCR7 in the proliferative response of CD8+ T cells to {gamma}c cytokines, but not in the response to immobilized anti-CD3 mAb. Interestingly, down-modulation of CCR7 has been described in TN (naive) cells upon stimulation with immobilized anti-CD3 plus anti-CD28 (10), suggesting that T cell proliferation can be coupled, or not, to differentiation depending on the specificity of signals (i.e., TCR triggering vs TCR triggering plus costimulation).

The Ag-independent maturation of a fraction of CD8+ T cells from TILN suggests that {gamma}c cytokines, such as IL-2 and IL-15, may be exploited for promoting the development of antitumor effectors in cancer patients for immunotherapy purposes (35). This goal appears relevant in the light of the frequent identification of anti-tumor CD8+ T cells at early stages of differentiation at the tumor site. Thus, the available evidence suggests that a large fraction of melanoma patients may benefit from strategies aimed at promoting functional maturation of their antitumor T cells. In principle, Ag-independent T cell differentiation to the effector stage could reduce the need for targeting specific tumor Ags, thus avoiding the risk of tumor resistance due to Ag loss variants. In addition, T cells from TILN may respond to {gamma}c cytokines mainly on the basis of their differentiation stage, which controls the expression of functional cytokine receptors, and independently from their Ag specificity. If antitumor T cells can be found at the tumor site, although in early stages of maturation, then cytokine-mediated differentiation would provide a way of activating T cells directed against a wide spectrum of tumor Ags. Thus, cytokine-induced differentiation of TILN populations, enriched for antitumor T cells, may represent a potential application for improving protocols of immunotherapy for cancer.


    Acknowledgments
 
We are grateful to the melanoma patients for their generous participation in this study.


    Footnotes
 
1 This work was supported in part by grants from Associazione Italiana per la Ricerca sul Cancro (Milan, Italy), Istituto Superiore di Sanita’ (Rome, Italy), Ministry of Health (Rome, Italy), Consiglio Nazionale delle Ricerche (Rome, Italy), and Compagnia di S. Paolo (Torino, Italy). Back

2 Address correspondence and reprint requests to Dr. Andrea Anichini, Human Tumor Immunobiology Unit, Department of Experimental Oncology, Istituto Nazionale per lo Studio e la Cura dei Tumori, Via Venezian 1, 20133 Milan, Italy. E-mail address: andrea.anichini{at}istitutotumori.mi.it Back

3 Abbreviations used in this paper: TN, T naive; {gamma}c, common {gamma} chain; TCM, T central memory; TEM, T effector memory; TEMRA, T CD45RA+ effector memory; TFLN, tumor-free lymph node; TILN, tumor-invaded lymph node. Back

Received for publication March 24, 2003. Accepted for publication June 3, 2003.


    References
 Top
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
 References
 

  1. Rosenberg, S. A.. 2001. Progress in human tumour immunology and immunotherapy. Nature 411:380.[Medline]
  2. Houghton, A. N., J. S. Gold, N. E. Blachere. 2001. Immunity against cancer: lessons learned from melanoma. Curr. Opin. Immunol. 13:134.[Medline]
  3. Kaech, S. M., E. J. Wherry, R. Ahmed. 2002. Effector and memory T-cell differentiation: implications for vaccine development. Nat. Rev. Immunol. 2:251.[Medline]
  4. Yee, C., S. R. Riddell, P. D. Greenberg. 2001. In vivo tracking of tumor-specific T cells. Curr. Opin. Immunol. 13:141.[Medline]
  5. Hamann, D., P. A. Baars, M. H. Rep, B. Hooibrink, S. R. Kerkhof-Garde, M. R. Klein, R. A. van Lier. 1997. Phenotypic and functional separation of memory and effector human CD8+ T cells. J. Exp. Med. 186:1407.[Abstract/Free Full Text]
  6. Sallusto, F., D. Lenig, R. Forster, M. Lipp, A. Lanzavecchia. 1999. Two subsets of memory T lymphocytes with distinct homing potentials and effector functions. Nature 401:708.[Medline]
  7. Champagne, P., G. S. Ogg, A. S. King, C. Knabenhans, K. Ellefsen, M. Nobile, V. Appay, G. P. Rizzardi, S. Fleury, M. Lipp, et al 2001. Skewed maturation of memory HIV-specific CD8 T lymphocytes. Nature 410:106.[Medline]
  8. Appay, V., P. R. Dunbar, M. Callan, P. Klenerman, G. M. Gillespie, L. Papagno, G. S. Ogg, A. King, F. Lechner, C. A. Spina, et al 2002. Memory CD8+ T cells vary in differentiation phenotype in different persistent virus infections. Nat. Med. 8:379.[Medline]
  9. Willis, M. R., G. Okecha, M. P. Weekes, M. K. Gandhi, P. J. G. Sissons, A. J. Carmichael. 2002. Identification of naïve or antigen-experienced human CD8+ T cells by expression of costimulation and chemokine receptors: analysis of the human cytomegalovirus-specific CD8+ T cell response. J. Immunol. 168:5455.[Abstract/Free Full Text]
  10. Geginat, J., F. Sallusto, A. Lanzavecchia. 2001. Cytokine-driven proliferation and differentiation of human naïve, central memory and effector memory CD4+ T cells. J. Exp. Med. 194:1711.[Abstract/Free Full Text]
  11. Geginat, J., A. Lanzavecchia, F. Sallusto. 2003. Proliferation and differentiation potential of human CD8+ memory T-cell subsets in response to antigen or homeostatic cytokines. Blood 10:1182.
  12. Wherry, E. J., V. Teichgraber, T. C. Becker, D. Masopust, S. M. Kaech, R. Antia, U. H. Von Andrian, R. Ahmed. 2003. Lineage relationship and protective immunity of memory CD8 T cell subsets. Nat. Immunol. 4:225.[Medline]
  13. Dunbar, P. R., C. L. Smith, D. Chao, M. Salio, D. Shepherd, F. Mirza, M. Lipp, A. Lanzavecchia, F. Sallusto, A. Evans, et al 2000. A shift in the phenotype of melan-A-specific CTL identifies melanoma patients with an active tumor-specific immune response. J. Immunol. 165:6644.[Abstract/Free Full Text]
  14. Valmori, D., C. Scheibenbogen, V. Dutoit, D. Nagorsen, A. M. Asemissen, V. Rubio-Godoy, D. Rimoldi, P. Guillaume, P. Romero, D. Schadendorf, et al 2002. Circulating tumor-reactive CD8+ T cells in melanoma patients contain a CD45RA+ CCR7- effector subset exerting ex vivo tumor-specific cytolytic activity. Cancer Res. 62:1743.[Abstract/Free Full Text]
  15. Jager, E., H. Hohn, A. Necker, R. Forster, J. Karbach, K. Freitag, C. Neukirch, C. Castelli, R. D. Salter, A. Knuth, et al 2002. Peptide-specific CD8+ T cell evolution in-vivo: response to peptide vaccination with melan-A/Mart-1. Int. J. Cancer 98:376.[Medline]
  16. Speiser, D. E., D. Lienard, M. Pittet, P. Batard, D. Rimoldi, P. Guillaume, J. C. Cerottini, P. Romero. 2002. In vivo activation of melanoma-specific CD8+ T cells by endogenous tumor antigen and peptide vaccines: a comparison to virus-specific T cells. Eur. J. Immunol. 32:731.[Medline]
  17. Monsurrò, V., D. Nagorsen, E. Wang, M. Provenzano, M. E. Dudley, S. A. Rosenberg, F. M. Marincola. 2002. Functional heterogeneity of vaccine-induced CD8+ T cells. J. Immunol. 168:5933.[Abstract/Free Full Text]
  18. Balch, C. M., A. C. Buzaid, S. J. Soong, M. B. Atkins, N. Cascinelli, D. G. Coit, I. D. Fleming, J. E. Gershenwald, A. Houghton, Jr., J. M. Kirkwood, et al 2001. Final version of the American Joint Committee on Cancer staging system for cutaneous melanoma. J. Clin. Oncol. 19:3635.[Abstract/Free Full Text]
  19. Anichini, A., A. Molla, R. Mortarini, G. Tragni, I. Bersani, M. Di Nicola, A. M. Gianni, S. Pilotti, R. Dunbar, V. Cerundolo, et al 1999. An expanded peripheral T cell population to a cytotoxic T lymphocyte (CTL)-defined, melanocyte-specific antigen in metastatic melanoma patients impacts on generation of peptide-specific CTLs but does not overcome tumor escape from immune surveillance in metastatic lesions. J. Exp. Med. 190:651.[Abstract/Free Full Text]
  20. Giacomini, P., P. Natali, S. Ferrone. 1985. Analysis of the interaction between a human high molecular weight melanoma-associated antigen and the monoclonal antibodies to three distinct antigenic determinants. J. Immunol. 135:696.[Abstract]
  21. Kawakami, Y., S. Eliyahu, K. Sakaguchi, P. F. Robbins, L. Rivoltini, J. R. Yannelli, E. Appella, S. A. Rosenberg. 1994. Identification of the immunodominant peptides of the MART-1 human melanoma antigen recognized by the majority of HLA-A2-restricted tumor infiltrating lymphocytes. J. Exp. Med. 180:347.[Abstract/Free Full Text]
  22. Valmori, D., J. F. Fonteneau, C. M. Lizana, N. Gervois, D. Lienard, D. Rimoldi, V. Jongeneel, F. Jotereau, J. C. Cerottini, P. Romero. 1998. Enhanced generation of specific tumor-reactive CTL in vitro by selected Melan-A/Mart-1 immunodominant peptide analogues. J. Immunol. 160:1750.[Abstract/Free Full Text]
  23. Kawakami, Y., S. Eliyahu, C. Jennings, K. Sakaguchi, X. Kang, S. Southwood, P. F. Robbins, A. Sette, E. Appella, S. A. Rosenberg. 1995. Recognition of multiple epitopes in the human melanoma antigen gp100 by tumor-infiltrating T lymphocytes associated with in vivo tumor regression. J. Immunol. 154:3961.[Abstract]
  24. Van der Bruggen, P., J. Bastin, T. Gajewski, P. G. Coulie, P. Boel, C. De Smet, C. Traversari, A. Townsend, T. Boon. 1994. A peptide encoded by human gene MAGE-3 and presented by HLA-A2 induces cytolytic T lymphocytes that recognize tumor cells expressing MAGE-3. Eur. J. Immunol. 24:3038.[Medline]
  25. Jager, E., Y. T. Chen, J. W. Drijfhout, J. Karbach, M. Ringhoffer, D. Jager, M. Arand, H. Wada, Y. Noguchi, E. Stockert, et al 1998. Simultaneous humoral and cellular immune response against cancer-testis antigen NY-ESO-1: definition of human histocompatibility leukocyte antigen (HLA)-A2-binding peptide epitopes. J. Exp. Med. 187:265.[Abstract/Free Full Text]
  26. Morrison, J., J. Elvin, F. Latron, F. Gotch, R. Moots, J. L. Strominger, A. McMichael. 1992. Identification of the nonamer peptide from influenza A matrix protein and the role of pockets of HLA-A2 in its recognition by cytotoxic T lymphocytes. Eur. J. Immunol. 22:903.[Medline]
  27. Russo, C., A. K. Ng, M. A. Pellegrino, S. Ferrone. 1983. The monoclonal antibody CR11–351 discriminates HLA-A2 variants identified by T cells. Immunogenetics 18:23.[Medline]
  28. Eisen, M. B., P. T. Spellman, P. O. Brown, D. Botstein. 1998. Cluster analysis and display of genome-wide expression patterns. Proc. Natl. Acad. Sci. USA 95:14863.[Abstract/Free Full Text]
  29. Manjunath, N., P. Shankar, J. Wan, W. Weninger, M. A. Crowley, K. Hieshima, T. A. Springer, X. Fan, H. Shen, J. Lieberman, et al 2001. Effector differentiation is not a prerequisite for generation of memory cytotoxic T lymphocytes. J. Clin. Invest. 108:871.[Medline]
  30. Tough, D. F., P. Borrow, J. Sprent. 1996. Induction of bystander T cell proliferation by viruses and type I interferon in vivo. Science 272:1947.[Abstract]
  31. Zhang, X., S. Sun, I. Hwang, D. F. Tough, J. Sprent. 1998. Potent and selective stimulation of memory-phenotype CD8+ T cells in vivo by IL-15. Immunity 8:591.[Medline]
  32. Pereno, R., J. Giron-Michel, A. Gaggero, E. Cazes, R. Meazza, M. Monetti, E. Monaco, Z. Mishal, C. Jasmin, F. Indiveri, et al 2000. IL-15/IL-15R{alpha} intracellular trafficking in human melanoma cells and signal transduction through the IL-15R{alpha}. Oncogene 19:5153.[Medline]
  33. Lu, C., C. Sheehan, J. W. Rak, C. A. Chambers, N. Hozumi, R. S. Kerbel. 1996. Endogenous interleukin 6 can function as an in vivo growth-stimulatory factor for advanced-stage human melanoma cells. Clin. Cancer Res. 2:1417.[Abstract]
  34. Yue, F. Y., R. Dummer, R. Geertsen, G. Hofbauer, E. Laine, S. Manolio, G. Burg. 1997. Interleukin-10 is a growth factor for human melanoma cells and down-regulates HLA class-I, HLA class-II and ICAM-1 molecules. Int. J. Cancer 71:630.[Medline]
  35. Fehniger, T. A., M. A. Cooper, M. A. Caligiuri. 2002. Interleukin-2 and interleukin-15: immunotherapy for cancer. Cytokine Growth Factor Rev. 13:169.[Medline]



This article has been cited by other articles:


Home page
Int ImmunolHome page
J. G. Casado, O. DelaRosa, G. Pawelec, E. Peralbo, E. Duran, F. Barahona, R. Solana, and R. Tarazona
Correlation of effector function with phenotype and cell division after in vitro differentiation of naive MART-1-specific CD8+ T cells
Int. Immunol., January 1, 2009; 21(1): 53 - 62.
[Abstract] [Full Text] [PDF]


Home page
Cancer Res.Home page
C. Badoual, G. Bouchaud, N. E. H. Agueznay, E. Mortier, S. Hans, A. Gey, F. Fernani, S. Peyrard, P. L. -Puig, P. Bruneval, et al.
The Soluble {alpha} Chain of Interleukin-15 Receptor: A Proinflammatory Molecule Associated with Tumor Progression in Head and Neck Cancer
Cancer Res., May 15, 2008; 68(10): 3907 - 3914.
[Abstract] [Full Text] [PDF]


Home page
J. Immunol.Home page
R. B. Smeltz
Profound Enhancement of the IL-12/IL-18 Pathway of IFN-{gamma} Secretion in Human CD8+ Memory T Cell Subsets via IL-15
J. Immunol., April 15, 2007; 178(8): 4786 - 4792.
[Abstract] [Full Text] [PDF]


Home page
BloodHome page
J. Carrasco, D. Godelaine, A. Van Pel, T. Boon, and P. van der Bruggen
CD45RA on human CD8 T cells is sensitive to the time elapsed since the last antigenic stimulation
Blood, November 1, 2006; 108(9): 2897 - 2905.
[Abstract] [Full Text] [PDF]


Home page
Cancer Res.Home page
A. Anichini, R. Mortarini, D. Nonaka, A. Molla, C. Vegetti, E. Montaldi, X. Wang, and S. Ferrone
Association of Antigen-Processing Machinery and HLA Antigen Phenotype of Melanoma Cells with Survival in American Joint Committee on Cancer Stage III and IV Melanoma Patients.
Cancer Res., June 15, 2006; 66(12): 6405 - 6411.
[Abstract] [Full Text] [PDF]


Home page
BloodHome page
A. Anichini, R. Mortarini, L. Romagnoli, P. Baldassari, A. Cabras, C. Carlo-Stella, A. M. Gianni, and M. Di Nicola
Skewed T-cell differentiation in patients with indolent non-Hodgkin lymphoma reversed by ex vivo T-cell culture with {gamma}c cytokines
Blood, January 15, 2006; 107(2): 602 - 609.
[Abstract] [Full Text] [PDF]


Home page
Clin. Cancer Res.Home page
M. Di Nicola, C. Carlo-Stella, R. Mortarini, P. Baldassari, A. Guidetti, G. F. Gallino, M. Del Vecchio, F. Ravagnani, M. Magni, P. Chaplin, et al.
Boosting T Cell-Mediated Immunity to Tyrosinase by Vaccinia Virus-Transduced, CD34+-Derived Dendritic Cell Vaccination: A Phase I Trial in Metastatic Melanoma
Clin. Cancer Res., August 15, 2004; 10(16): 5381 - 5390.
[Abstract] [Full Text] [PDF]


Home page
J. Immunol.Home page
E. Mallard, F. Vernel-Pauillac, T. Velu, F. Lehmann, J.-P. Abastado, M. Salcedo, and N. Bercovici
IL-2 Production by Virus- and Tumor-Specific Human CD8 T Cells Is Determined by Their Fine Specificity
J. Immunol., March 15, 2004; 172(6): 3963 - 3970.
[Abstract] [Full Text] [PDF]


This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Anichini, A.
Right arrow Articles by Mortarini, R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Anichini, A.
Right arrow Articles by Mortarini, R.
Right arrowPubmed/NCBI databases
*Substance via MeSH
Medline Plus Health Information
*Melanoma


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS