14 results on '"Le Dréan E"'
Search Results
2. Heterogeneity of biologic responses of melanoma-specific CTL
- Author
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Jf, Fonteneau, Le Dréan E, Le Guiner S, Nadine Gervois, Diez E, Jotereau F, Interactions récepteurs ligands en immunocancérologie et immunopathologie, IFR26-Institut National de la Santé et de la Recherche Médicale (INSERM), and GERVOIS, Nadine
- Subjects
Cytotoxicity, Immunologic ,[SDV]Life Sciences [q-bio] ,Immunology ,Flow Cytometry ,[SDV] Life Sciences [q-bio] ,Antigens, Neoplasm ,T-Lymphocyte Subsets ,COS Cells ,Tumor Cells, Cultured ,Animals ,Cytokines ,Humans ,Immunology and Allergy ,Melanoma ,T-Lymphocytes, Cytotoxic - Abstract
To better understand how Ag density influences the various biologic responses of CTL, we analyzed lysis and, at the single cell level, cytokine production by a panel of melanoma-specific CTL clones. Titration experiments done with peptide-pulsed TAP-deficient T2 cells indicated that: 1) Ag density affects both the fraction of responding cells and the amount of cytokine secreted by each cell. 2) Different responses have a relative Ag requirement that may vary between clones. Lysis and secretion of IFN-gamma, and for most clones' secretion of TNF-alpha, required lower Ag densities, by one or two logs, than IL-2 and granulocyte-macrophage CSF secretion. 3) In a significant fraction of IFN-gamma-secreting cells, IL-2 production is not induced. 4) A large fraction of cloned cells is refractory to lymphokine gene activation for about 2 wk after previous stimulation. Together these data indicate that CTL biologic responses are controlled by variable Ag thresholds and by additional parameters affecting activation requirements of each cell. A similar heterogeneity of cytokine responses was observed to Ag endogenously presented by melanoma cells. As a consequence, most melanoma lines, including those with the highest Ag expression, could trigger only low CTL fractions to secrete IL-2 and, also for most clones, granulocyte-macrophage CSF. This may be an important component of the inefficiency of specific CTL in cancer patients.
- Published
- 1997
3. Detection by real‐time RT‐PCR of a bovine respiratory syncytial virus vaccine in calves vaccinated intranasally
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Belloc, C., primary, Guattéo, R, additional, Bareille, N., additional, Seegers, H., additional, Assié, S., additional, Douart, A., additional, Le Dréan, E., additional, Maingourd, C., additional, and Sellal, E., additional
- Published
- 2009
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4. Heterogeneity of biologic responses of melanoma-specific CTL.
- Author
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Fonteneau, J F, primary, Le Dréan, E, additional, Le Guiner, S, additional, Gervois, N, additional, Diez, E, additional, and Jotereau, F, additional
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- 1997
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5. Detection by real-time RT-PCR of a bovine respiratory syncytial virus vaccine in calves vaccinated intranasally.
- Author
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Timsit, E., Le Dréan, E., Maingourd, C., Belloc, C., Guattéo, R., Bareille, N., Seegers, H., Douart, A., Sellal, E., and Assié, S.
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CALVES , *RESPIRATORY syncytial virus , *POLYMERASE chain reaction , *VACCINATION , *VIRAL vaccines , *SURGICAL swabs , *ANIMAL health - Abstract
Seventeen four- to five-week-old calves that were not shedding bovine respiratory syncytial virus (BRSV) were vaccinated intranasally against the disease and sampled by nasal swabbing on 16 different days for up to 20 days after vaccination. BRSV vaccine virus was detected in 15 of the 17 calves. Five of the calves were PCR positive on only one swab, eight were PCR positive on two to five swabs and two were PCR positive on more than five swabs. Twelve of the calves were positive only before day 14 and three were positive after day 14. The nasal shedding of BRSV vaccine virus was very variable. [ABSTRACT FROM AUTHOR]
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- 2009
6. Tracking potential Leptospira sources following human cases of leptospirosis: A One Health approach applied to an ecosystem in Brittany, France.
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Harran E, Kuntz G, Decors A, Bourhy P, Auffret A, Bigeard C, Cherel D, Kodjo A, Le Dréan E, Lejas C, Lequeux G, Pilard MA, Pivette M, Guillois Y, and Ayral F
- Abstract
Pathogenic Leptospira can cause leptospirosis: a widespread, potentially fatal bacterial zoonosis whose risk is mediated by the soil and water features, animal host distributions, meaning the local ecosystem. When human cases of leptospirosis occur, it is challenging to track down their source because ecosystem-level epidemiological knowledge on Leptospira is needed. Between 2016 and 2019 in a focal riparian ecosystem, the human population experienced an outbreak and successive cases of leptospirosis attributable to L. kirschneri and L. interrogans . The epidemiological investigation was carried out using the One Health approach, as described in international health guidelines. As a first step in this process, we investigated leptospiral carriage in the main animal hosts found in the region. We sampled 143 nutrias, 17 muskrats, and 10 Norway rats using convenient trapping. DNA was extracted from their kidneys, lungs, and urine and subjected to real-time PCR (RT-PCR) targeting the Leptospira 16S rDNA and lfb1 genes. In the farms along the river's stretch of interest, we sampled serum from 439 cattle and used a microscopic agglutination test to detect the presence of antibodies against Leptospira . Urine samples were concomitantly obtained from 145 cattle and were used in two analyses: RT-PCR targeting the Leptospira 16S rDNA gene and Leptospira culturing. We found th, wt rodents were the most likely source of the L. interrogans behind the human cases. The cattle tested negative for Leptospira DNA but positive for antibodies against the serogroups implicated in the human cases. We failed to identify the potential source of the L. kirschneri responsible for several human cases of leptospirosis. Our results call for further clarification of the Leptospira maintenance community, which may comprise known maintenance hosts, such as rodents, as well as taxa not commonly considered to be maintenance hosts but that can still spread Leptospira . The resulting research network will collaboratively conduct future eco-epidemiological surveys to illuminate the leptospirosis risks faced by humans and animals within ecosystems., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier B.V.)
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- 2024
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7. Anatomy of bluetongue virus serotype 8 epizootic wave, France, 2007-2008.
- Author
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Durand B, Zanella G, Biteau-Coroller F, Locatelli C, Baurier F, Simon C, Le Dréan E, Delaval J, Prengère E, Beauté V, and Guis H
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- Animals, Antibodies, Viral blood, Bluetongue blood, Bluetongue virus isolation & purification, Cattle, Cattle Diseases blood, Cross-Sectional Studies, Ecosystem, France epidemiology, Seasons, Seroepidemiologic Studies, Serotyping, Sheep virology, Bluetongue epidemiology, Bluetongue virus classification, Cattle Diseases epidemiology, Cattle Diseases virology, Disease Outbreaks veterinary
- Abstract
The introduction of bluetongue virus serotype 8 into northern Europe at the end of summer 2006 initiated one of the most widespread epizootics of bluetongue infection ever to occur. In winter 2007-2008, a cross-sectional serologic study was conducted in France along a transect perpendicular to the epizootic wave. Cattle herd-level seroprevalence varied from 4% to 100%, and animal-level seroprevalence from <1% to 40%. Only a low proportion of seropositive herds reported clinical cases in 2007. Sheep flocks were less frequently affected than cattle herds. The local occurrence of clinical cases and environmental indicators linked to forests were seropositivity risk factors, whereas the local density of cows had a protective effect. Overall results suggest that amplification of virus circulation in affected herds played a limited role in the epizootic wave diffusion and that bluetongue virus serotype 8 circulation in natural ecosystems could have played a substantial role in this progression.
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- 2010
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8. Evaluation of a commercial real-time reverse transcription polymerase chain reaction kit for the diagnosis of Bovine respiratory syncytial virus infection.
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Timsit E, Maingourd C, Le Dréan E, Belloc C, Seegers H, Douart A, and Assié S
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- Animals, Cattle, Cattle Diseases virology, Cattle Diseases diagnosis, Respiratory Syncytial Virus Infections veterinary, Respiratory Syncytial Virus, Bovine, Reverse Transcriptase Polymerase Chain Reaction veterinary
- Abstract
Recently a commercial real-time reverse transcription polymerase chain reaction (RT-PCR) kit has been marketed for the detection of Bovine respiratory syncytial virus (BRSV). However, diagnostic interpretation of the results of this kit requires its comparison to commonly used methods. Therefore, the objective of this study was to evaluate the performance of this kit in comparison with the conventional direct fluorescent antibody test (FAT). Twenty BRSV strains and 14 heterologous bovine viruses were used to check the kit's sensitivity and specificity. The efficiency and detection limit of the kit were determined by testing dilution series of a BRSV strain. The comparison between real-time RT-PCR kit and FAT was performed with 94 clinical samples from calves with clinical signs of respiratory disease including lung tissues (n = 55), transtracheal aspiration samples (n = 20), and nasal swab samples (n = 19). All of the BRSV strains tested were detected by real-time RT-PCR. No cross-reaction was shown with the 14 heterologous bovine viruses. The real-time RT-PCR was 99.3% efficient with a detection limit of 0.1 TCID(50) (50% tissue culture infective dose). The results of real-time RT-PCR and FAT were concordant for 65 of the 94 clinical samples tested. The remaining 29 clinical samples were positive by real-time RT-PCR and negative by FAT, demonstrating the higher sensitivity of real-time RT-PCR. In conclusion, the kit evaluated in this study was sensitive, specific, and had a low threshold of detection. Furthermore, the use of this kit instead of FAT allows an improvement of the sensitivity for the detection of BRSV in clinical samples.
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- 2010
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9. Frequency and relative fraction of tumor antigen-specific T cells among lymphocytes from melanoma-invaded lymph nodes.
- Author
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Labarriere N, Pandolfino MC, Raingeard D, Le Guiner S, Diez E, Le Dréan E, Dreno B, and Jotereau F
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- HLA-A2 Antigen immunology, Humans, Interferon-gamma analysis, Interferon-gamma metabolism, Interleukin-2 metabolism, MART-1 Antigen, Melanoma pathology, Monophenol Monooxygenase immunology, Neoplasm Invasiveness, Neoplasm Proteins immunology, Sensitivity and Specificity, T-Lymphocytes metabolism, T-Lymphocytes, Cytotoxic immunology, T-Lymphocytes, Cytotoxic metabolism, Tumor Necrosis Factor-alpha metabolism, Antigens, Neoplasm immunology, Epitopes immunology, Lymph Nodes immunology, Lymph Nodes pathology, Melanoma immunology, T-Lymphocytes immunology
- Abstract
Several tumor antigens have been described as candidates for immunotherapy. Our study compared HLA-A2-restricted epitopes from 5 antigens commonly expressed by melanomas, i.e., Melan-A/MART-1 peptides (26-35 and 27-35), tyrosinase (368-376), gp-100 (280-288), MAGE-3 (271-279) and NA17-A (1-10), for their relative capacity to promote the development of cytotoxic and cytokine-producing specific CD8+ lymphocytes within melanoma-invaded lymph nodes. We used short-term cultured melanoma-invaded lymph node lymphocytes (MILLs) and tested responses developed by these cells to peptide-pulsed TAP-deficient T2 cells. We measured both the lytic response developed by MILLs and the fraction of these cells that secreted interferon-gamma (IFN-gamma), as deduced from intracellular cytokine labeling. Reverse transcription-polymerase chain reaction (RT-PCR) was used to analyze the expression of the 5 antigens within melanoma-invaded lymph nodes. Melan-A/MART-1, tyrosinase and gp-100 peptides were recognized by MILLs derived, respectively, from 8 of 20, 5 of 19 and 4 of 20 melanoma-invaded lymph nodes expressing these antigens. Most MILLs specific for Melan-A/MART-1 and tyrosinase exhibited both lysis and IFN-gamma responses, whereas most of those specific for gp-100 developed only lysis. Weak lysis without IFN-gamma secretion was developed against NA17-A and MAGE-3 peptides by MILLs from, respectively, 3 of 9 and 2 of 14 lymph nodes expressing these antigens. Our data show a prevalence of both cytotoxic and IFN-gamma-secreting effector T cells specific for differentiation antigens within HLA-A2 melanoma-invaded lymph nodes, which makes these antigens attractive targets for specific immunotherapy.
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- 1998
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10. LFA-3 co-stimulates cytokine secretion by cytotoxic T lymphocytes by providing a TCR-independent activation signal.
- Author
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Le Guiner S, Le Dréan E, Labarrière N, Fonteneau JF, Viret C, Diez E, and Jotereau F
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- Animals, Cytokines biosynthesis, Cytokines immunology, Humans, Rats, Signal Transduction immunology, Tumor Cells, Cultured, CD58 Antigens immunology, Lymphocyte Activation immunology, Lymphocytes, Tumor-Infiltrating immunology, Melanoma immunology, Receptors, Antigen, T-Cell immunology, T-Lymphocytes, Cytotoxic immunology
- Abstract
T cell activation is known to depend not only on efficient antigen recognition and subsequent signaling through TCR, but also on interactions involving multiple adhesion and accessory molecules such as CD28/B7, LFA-1/ICAM-1 and LFA-3/CD2. The present study dissects the role of LFA-3/CD2 interactions in the activation of melanoma-specific CD8+ T cell clones. To this end we analyzed the influence of LFA-3 density on melanoma cells on lysis and cytokine production (TNF, IL-2, IFN-gamma) by T cells following activation by various amounts of antigenic peptides. Our results indicate that increasing LFA-3 density on melanoma cells variably affects their lysis susceptibility, but systematically and considerably enhances cytokine production by melanoma-specific cytotoxic T lymphocyte (CTL) clones. At any stimulatory antigen density, LFA-3 increased the fraction of responding cells and/or cytokine amounts produced by individual cells, without affecting TCR down-regulation. These results show that CD2 engagement increases cytokine gene activation essentially by providing to T cells a TCR-independent co-activation signal. From a practical point of view, our data demonstrate that the level of LFA-3 expressed on tumors critically affects cytokine production by specific CTL and thus the efficiency of specific immune reactions mediated by these cells.
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- 1998
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11. Inhibition of antigen-induced T cell response and antibody-induced NK cell cytotoxicity by NKG2A: association of NKG2A with SHP-1 and SHP-2 protein-tyrosine phosphatases.
- Author
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Le Dréan E, Vély F, Olcese L, Cambiaggi A, Guia S, Krystal G, Gervois N, Moretta A, Jotereau F, and Vivier E
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- Amino Acid Sequence, Animals, Antigens, CD chemistry, Dimerization, Humans, Immunosuppressive Agents pharmacology, Intracellular Signaling Peptides and Proteins, Killer Cells, Natural immunology, Kinetics, Lymphocytes, Tumor-Infiltrating, Macromolecular Substances, Melanoma immunology, Membrane Glycoproteins chemistry, Molecular Sequence Data, NK Cell Lectin-Like Receptor Subfamily D, Protein Binding, Protein Tyrosine Phosphatase, Non-Receptor Type 11, Protein Tyrosine Phosphatase, Non-Receptor Type 6, Protein Tyrosine Phosphatases chemistry, Rats, Receptors, IgG physiology, Recombinant Fusion Proteins immunology, T-Lymphocytes, Cytotoxic immunology, Tumor Cells, Cultured, Tumor Necrosis Factor-alpha metabolism, Antibody-Dependent Cell Cytotoxicity drug effects, Antigens, CD pharmacology, Antigens, CD physiology, Killer Cells, Natural drug effects, Lectins, C-Type, Lymphocyte Activation drug effects, Membrane Glycoproteins pharmacology, Membrane Glycoproteins physiology, Protein Tyrosine Phosphatases physiology, T-Lymphocytes, Cytotoxic drug effects
- Abstract
Subsets of T and natural killer (NK) lymphocytes express the CD94-NKG2A heterodimer, a receptor for major histocompatibility complex class I molecules. We show here that engagement of the CD94-NKG2A heterodimer inhibits both antigen-driven tumor necrosis factor (TNF) release and cytotoxicity on melanoma-specific human T cell clones. Similarly, CD16-mediated NK cell cytotoxicity is extinguished by cross-linking of the CD94-NKG2A heterodimer. Combining in vivo and in vitro analysis, we report that both I/VxYxxL immunoreceptor tyrosine-based inhibition motifs (ITIM) present in the NKG2A intracytoplasmic domain associate upon tyrosine phosphorylation with the protein tyrosine phosphatases SHP-1 and SHP-2, but not with the polyinositol phosphatase SHIP Determination of the dissociation constant, using surface plasmon resonance analysis, indicates that NKG2A phospho-ITIM interact directly with the SH2 domains of SHP-1 and SHP-2 with a high affinity. Engagement of the CD94-NKG2A heterodimer therefore appears as a protein-tyrosine phosphatase-based strategy that negatively regulates both antigen-induced T cell response and antibody-induced NK cell cytotoxicity. Our results suggest that this inhibitory pathway sets the threshold of T and NK cell activation.
- Published
- 1998
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12. T cell activation by antigens on human melanoma cells--co-stimulation by B7-1 is neither sufficient nor necessary to stimulate IL-2 secretion by melanoma-specific T cell clones in vitro.
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Viret C, Gervois N, Guilloux Y, Le Dréan E, Diez E, and Jotereau F
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- Animals, Antibodies, Monoclonal immunology, B7-1 Antigen genetics, CD28 Antigens immunology, CD58 Antigens genetics, CD58 Antigens physiology, Cell Line, Clone Cells, Fibrosarcoma, Humans, Melanoma pathology, Mice, Neoplasm Proteins immunology, Recombinant Fusion Proteins biosynthesis, Recombinant Fusion Proteins immunology, T-Lymphocyte Subsets metabolism, Transfection, B7-1 Antigen physiology, Interleukin-2 metabolism, Lymphocyte Activation, Lymphocytes, Tumor-Infiltrating immunology, Melanoma immunology, T-Lymphocyte Subsets immunology
- Abstract
B7-1 expression, induced by transfection in poorly immunogenic murine tumours, was shown to elicit a T cell-mediated rejection of these tumours and further active immunity against the non-transfected tumour. We therefore asked to what level similarly induced expression of B7 on human melanoma cells would affect the antigen-dependent responses of tumour-specific T cell clones in vitro. Data presented show that B7-1 expression by melanoma lines: (i) significantly induced, or improved, an IL-2-dependent proliferative response of such clones to the antigen; (ii) increased the amount of IL-2 produced by two clones in response to the parental non-transfected tumour cells; and (iii) increased the TNF responses of all the CD4+ clones. However, despite these clear co-stimulatory effects on antigen-induced responses of all T cell clones, which demonstrated an effective interaction of the B7-1 transfected molecule with one or the other of its counter-receptors expressed on T cell clones, B7 co-stimulation did not correct the defect of IL-2 secretion exhibited by many of these clones in response to in vitro antigen presentation by melanoma cells. We further show that defective IL-2 secretion in response to melanoma antigens was not due to a T cell clone refractoriness induced by the culture, since one of these clones could be induced to secrete IL-2 by an antigen-expressing melanoma line, upon increased lymphocyte function associated antigen-3 expression induced by gene transfection. Together these data suggest that defective IL-2 secretion by many tumour-infiltrating lymphocytes clones in response to antigen presentation by melanoma cells in vitro is not exclusively due to the inability of these cells to provide an appropriate co-stimulation through the B7-1 molecule.
- Published
- 1995
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13. HLA class II-restricted recognition of common tumor epitopes on human melanoma cells by CD4+ melanoma-infiltrating lymphocytes.
- Author
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Le Dréan E, Gervois N, Diez E, Semana G, Dreno B, and Jotereau F
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- Alleles, Animals, Antibodies, Monoclonal immunology, Antibodies, Monoclonal pharmacology, CD4-Positive T-Lymphocytes metabolism, Cattle, Clone Cells immunology, Clone Cells metabolism, Genes, MHC Class II, HLA-D Antigens genetics, Humans, Lymphocytes immunology, Lymphocytes, Tumor-Infiltrating metabolism, Lymphotoxin-alpha metabolism, Antigens, Neoplasm immunology, CD4-Positive T-Lymphocytes immunology, HLA-D Antigens immunology, Lymphocytes, Tumor-Infiltrating immunology, Melanoma immunology
- Abstract
CD4+ T cell clones derived from lymphocytes infiltrating four human melanomas specifically recognized melanoma-derived tumor epitopes as shown by secretion of tumor necrosis factor (TNF) in vitro upon interaction with autologous melanoma cells, whereas they did not recognize HLA class II-expressing autologous lymphoblasts or HLA class II mismatched allogeneic melanoma cells. Specificity was further established by demonstrating that TNF responses to tumor cells were inhibited by HLA-DR or HLA-DQ monoclonal antibodies. Most of these clones cross-reacted with allogeneic melanoma cells expressing a potentially restricting HLA allele or a structurally similar one. These data show that shared epitopes of human melanoma cells presented on HLA class II molecules are frequently recognized by autologous CD4+ T lymphocytes.
- Published
- 1995
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14. Defective lymphokine production by most CD8+ and CD4+ tumor-specific T cell clones derived from human melanoma-infiltrating lymphocytes in response to autologous tumor cells in vitro.
- Author
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Guilloux Y, Viret C, Gervois N, Le Dréan E, Pandolfino MC, Diez E, and Jotereau F
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- Antibodies, Monoclonal, Antigens, CD physiology, CD3 Complex immunology, CD4-Positive T-Lymphocytes immunology, CD58 Antigens, CD8 Antigens immunology, Humans, Interleukin-2 biosynthesis, Ionophores pharmacology, Lymphocytes, Tumor-Infiltrating immunology, Membrane Glycoproteins physiology, T-Lymphocytes, Cytotoxic immunology, Tetradecanoylphorbol Acetate pharmacology, Transfection, Tumor Cells, Cultured, Cytokines biosynthesis, Melanoma immunology, T-Lymphocyte Subsets immunology
- Abstract
Human melanomas are infiltrated by tumor-reactive T lymphocytes. However, the ability of these cells to elicit a specific anti-tumor response in vivo remains to be established. Because lymphokine production is critical for T cell functions, we have analyzed the capacity of melanoma-specific tumor-infiltrating lymphocyte (TIL) clones to produce major lymphokines: interleukin-2 (IL-2), interferon-gamma (IFN-gamma) and interleukin-4 (IL-4), as well as tumor necrosis factor (TNF), in response to direct antigen presentation by autologous and allogeneic tumor cells. We report here that, upon stimulation by autologous melanoma cells, all TIL clones secreted TNF but only a few of them produced significant amounts of IL-2, IL-4 or IFN-gamma. Nonetheless, all these clones consistently produced two or three of these last lymphokines upon stimulation with phorbol myristate acetate and calcium ionophore, as well as IL-2 upon CD3 stimulation, showing the existence of three lymphokine profiles among them: Th1, Th0 and a profile characterized by IL-2 and IL-4, but not IFN-gamma secretion. Stimulation of TIL clones by allogeneic melanoma lines sharing the appropriate HLA-peptide complexes revealed that defective IL-2 production seemed to be a constant feature for some clones, while it was, for other clones, dependent on the antigen-presenting tumor cells. For this last type of clone, we further showed that defective IL-2 induction resulted from an LFA-3 defect of some melanoma cells or from distinct yet undefined defects of other melanoma lines. Our data suggest that defective lymphokine secretion may be an essential component of the in vivo failure of melanoma-reactive TIL to control tumor development. Interestingly both CD4+ and CD8+ TIL clones from one patient were fully activated by the autologous melanoma cells in vitro, supporting a potential role of such TIL in spontaneous or induced tumor rejection.
- Published
- 1994
- Full Text
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