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1.
Cancers (Basel) ; 12(5)2020 Apr 28.
Article in English | MEDLINE | ID: mdl-32353988

ABSTRACT

Background: The regulation of melanoma by noradrenergic signaling has gain attention since pre-clinical and clinical studies suggested a benefit of using beta-blockers to control disease progression. We need to confirm that human melanoma recapitulates the mechanisms described from pre-clinical models. Methods: The sources and targets of norepinephrine in the microenvironment of 20 human melanoma samples was investigated using immunostaining. The effect of an exposure to beta-blockers on immune cell type distribution and expression of immune response markers was assessed with immunostaining on 212 human primary melanoma. A statistical analysis explored the effect of an exposure to beta-blockers on progression free survival, melanoma related survival, and overall survival on the 286 eligible patients. Results: Tumor cells and macrophages may be a source of norepinephrine in melanoma microenvironment. Tumors from patients exposed to wide spectrum beta-blockers recapitulate the increased infiltration of T-lymphocytes and the increased production of granzyme B observed in pre-clinical models. An exposure to beta-blockers is associated with a better outcome in our cohort of melanoma patients. Conclusion: This study shows the association between an exposure to wide spectrum beta-blockers and markers of an effective anti-tumor immune response as well as the protective effect of beta-blockers in human melanoma patients.

2.
Rev Med Suisse ; 14(600): 670-675, 2018 Mar 28.
Article in French | MEDLINE | ID: mdl-29589653

ABSTRACT

Betablockers are used for decades in the treatment of cardiovascular diseases. Recently, the repurposing of the wide spectrum betablocker propranolol revolutionized the infantile hemangioma management. Besides, betablockers have been shown to significantly improve the prognosis of melanoma patients. Blocking the adrenergic receptors blocks the stress-induced tumorigenic pathways. Propranolol inhibits melanoma by downregulating the tumor angiogenesis but also tumor cell proliferation, invasiveness and local immune suppression. These antitumor effects have been observed in other cancers. The repurposing of propranolol has already changed the practice of pediatricians and dermatologists and may soon help oncologists treat various cancers.


Les bêtabloquants sont utilisés depuis des décennies pour les maladies cardiovasculaires. Le propranolol, bêtabloquant à large spectre, a récemment révolutionné la prise en charge de l'hémangiome infantile. Par ailleurs, ces molécules semblent améliorer le pronostic des patients atteints de mélanome. Le blocage des récepteurs adrénergiques inhibe les différentes voies protumorales induites par le stress. Les bêtabloquants freinent le développement du mélanome en inhibant la néoangiogenèse et la prolifération des cellules tumorales, l'invasion et l'immunosuppression locale. Ces effets antitumoraux sont aussi observés dans d'autres cancers. La réorientation des bêtabloquants a déjà changé la pratique quotidienne des pédiatres et dermatologues et pourrait bientôt concerner les oncologues.


Subject(s)
Adrenergic beta-Antagonists , Hemangioma , Adrenergic beta-Antagonists/therapeutic use , Cell Proliferation/drug effects , Dermatology/trends , Hemangioma/drug therapy , Humans , Infant , Propranolol
3.
Oncotarget ; 7(47): 77825-77837, 2016 Nov 22.
Article in English | MEDLINE | ID: mdl-27788481

ABSTRACT

In a previous study on a xenograft model of melanoma, we showed that the beta-adrenergic receptor antagonist propranolol inhibits melanoma development by modulating angiogenesis, proliferation and cell survival. Stress hormones can influence tumor development in different ways and norepinephrine was shown to downregulate antitumor immune responses by favoring the accumulation of immunosuppressive cells, impairing the function of lymphocytes. We assessed the effect of propranolol on antitumor immune response in the MT/Ret mouse model of melanoma. Propranolol treatment delayed primary tumor growth and metastases development in MT/Ret mice. Consistent with our previous observations in human melanoma xenografts, propranolol induces a decrease in cell proliferation and vessel density in the primary tumors and in metastases. In this immunocompetent model, propranolol significantly reduced the infiltration of myeloid cells, particularly neutrophils, in the primary tumor. Inversely, cytotoxic tumor infiltrating lymphocytes were more frequent in the tumor stroma of treated mice. In a consistent manner, we observed the same shift in the proportions of infiltrating leukocytes in the metastases of treated mice. Our results suggest that propranolol, by decreasing the infiltration of immunosuppressive myeloid cells in the tumor microenvironment, restores a better control of the tumor by cytotoxic cells.


Subject(s)
Antineoplastic Agents/administration & dosage , Melanoma, Experimental/drug therapy , Propranolol/administration & dosage , Skin Neoplasms/drug therapy , Animals , Antineoplastic Agents/pharmacology , Cell Proliferation/drug effects , Lymphocytes, Tumor-Infiltrating/drug effects , Melanoma, Experimental/immunology , Mice , Mice, Inbred C57BL , Neoplasm Metastasis , Propranolol/pharmacology , Proto-Oncogene Proteins c-ret/genetics , Skin Neoplasms/immunology , Treatment Outcome
5.
J Invest Dermatol ; 135(2): 525-531, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25178102

ABSTRACT

Recently, retrospective studies provided conflicting results on the benefit of ß-adrenoceptor-blockers (ß-blockers) on melanoma progression. Most of these studies did not define the ß-blocker used, making it difficult to understand the source of discrepancies between results. Therefore, we investigated the effect of non-cardioselective and cardioselective ß-blockers on melanoma progression at the cellular, molecular, and tumor levels. Here we show that the non-cardioselective ß-blocker propranolol hydrochloride (propranolol) inhibits proliferation and induces apoptosis in primary cell cultures derived from a primary and a metastasis of human melanoma and in melanoma cell lines. In contrast, the cardioselective ß-blocker metoprolol tartrate hardly affects melanoma cell survival or proliferation. We further highlight that a daily treatment with propranolol slows down tumor development in immunodeficient mice transplanted with human melanoma cells. RNA microarrays, quantitative PCR, and histochemistry analyses showed that propranolol regulates the expression of different genes involved in tumor angiogenesis, cell death, or proliferation. Thus, our results suggest that non-cardioselective ß-blockers affect melanoma progression, and bring first clues about the pathways involved in this antitumor effect.


Subject(s)
Adrenergic beta-Antagonists/pharmacology , Melanoma/drug therapy , Adult , Apoptosis/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Female , Humans , Melanoma/pathology , Metoprolol/pharmacology , Middle Aged , Neovascularization, Pathologic/prevention & control , Propranolol/pharmacology , Transcriptome , Xenograft Model Antitumor Assays
6.
Comput Biol Med ; 47: 36-43, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24530537

ABSTRACT

This paper theoretically evaluates lock-in thermal imaging for the early-stage detection of cutaneous melanoma. Lock-in thermal imaging is based on the periodic thermal excitation of the specimen under test. Resulting surface temperature oscillations are recorded with an infrared camera and allow the detection of variations of the sample's thermophysical properties under the surface. In this paper, the steady-state and transient skin surface temperatures are numerically derived for a different stage of development of the melanoma lesion using a two-dimensional axisymmetric multilayer heat-transfer model. The transient skin surface temperature signals are demodulated according to the digital lock-in principle to compute both a phase and an amplitude image of the lesions. The phase image can be advantageously used to accurately detect cutaneous melanoma at an early stage of development while the maximal phase shift can give precious information about the lesion invasion depth. The ability of lock-in thermal imaging to suppress disturbing subcutaneous thermal signals is demonstrated. The method is compared with the previously proposed pulse-based approaches, and the influence of the modulation frequency is further discussed.


Subject(s)
Early Detection of Cancer/methods , Melanoma , Models, Biological , Skin Neoplasms , Thermography/methods , Feasibility Studies , Humans , Melanoma/diagnosis , Melanoma/pathology , Skin Neoplasms/diagnosis , Skin Neoplasms/pathology , Skin Temperature , Thermodynamics , Melanoma, Cutaneous Malignant
7.
Dermatology ; 226(2): 101-4, 2013.
Article in English | MEDLINE | ID: mdl-23363889

ABSTRACT

BACKGROUND: Desmoplastic trichoepithelioma (DT) is a rare benign adnexal neoplasm considered to have follicular differentiation. It usually presents as an asymptomatic, firm, annular plaque with a raised border. The diagnosis of DT is based on clinical and histological features which can be similar to those of morpheiform basal cell carcinoma. Taking this into consideration, the use of another diagnostic technique would be very useful. Dermoscopy is a noninvasive diagnostic technique allowing a more accurate diagnosis. OBJECTIVES: To differentiate DT and morpheiform basal cell carcinoma by means of dermoscopy. METHODS: Here, we describe the dermoscopic features of a case of DT, and make a direct clinicopathological correlation by using the horizontally cut slides provided by Mohs micrographic surgery. RESULTS: On dermoscopy, DT shows well-defined borders and an ivory-white color, as well as prominent arborizing telangiectasias in the central area and on the right side. There are no leaf-like structures and no ovoid nests. This observation confirms and completes the first dermoscopic analysis of DT reported in the literature so far.


Subject(s)
Carcinoma, Basal Cell/pathology , Dermoscopy , Skin Neoplasms/pathology , Adolescent , Diagnosis, Differential , Humans , Male
9.
Cancer Prev Res (Phila) ; 5(1): 82-8, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21933913

ABSTRACT

Increased risk of secondary melanoma after breast cancer has been reported. Several lines of evidence suggest that elevated estrogen levels may be implicated in melanoma etiology. Accordingly, use of antiestrogens should be associated with decreased risk of melanoma. We compared melanoma incidence among a cohort of breast cancer patients with and without antiestrogen therapy, with data from the Geneva Cancer Registry. The cohort consisted of 7,360 women diagnosed with breast cancer between 1980 and 2005. About 54% of these patients received antiestrogens. All women were followed until December 2008. We compared cutaneous melanoma incidence rates among patients with and without antiestrogens with those expected in the general population by age and period standardized incidence ratios (SIR). A total of 34 women developed a melanoma during the follow-up period. Compared with the general population, the risk of melanoma was higher for patients who did not receive antiestrogens (SIR: 1.60, 95% CI: 1.08-2.12, P = 0.02). On the contrary, the risk was close to 1 (SIR: 0.98, 95% CI: 0.40-1.56, P = 0.57) for patients who received antiestrogen therapy. This study suggests that antiestrogen therapy modifies the risk of melanoma after breast cancer. Although our results are in agreement with the hypothesis that estrogens could play a role in melanoma occurrence, they need to be replicated in a larger study with data on potential confounders. .


Subject(s)
Breast Neoplasms/drug therapy , Estrogen Antagonists/therapeutic use , Estrogens/metabolism , Skin Neoplasms/secondary , Adult , Aged , Breast Neoplasms/complications , Cohort Studies , Female , Humans , Melanoma/etiology , Melanoma/secondary , Middle Aged , Neoplasms, Second Primary/etiology , Registries , Risk , Skin Neoplasms/etiology , Treatment Outcome
10.
J Immunother ; 32(8): 875-83, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19752746

ABSTRACT

Toll-like receptor ligands are potentially useful adjuvants for the development of clinical T cell vaccination. Here we investigated the novel Toll-like receptor2 ligand P40, the outer membrane protein A derived from Klebsiella pneumoniae. Seventeen human leukocyte antigen-A*0201 positive stage III/IV melanoma patients were vaccinated with P40 and Melan-A/Mart-1 peptide subcutaneously in monthly intervals. Adverse reactions were mild-to-moderate. Fourteen patients received at least 8 vaccinations and were thus evaluable for clinical tumor and immune responses. Seven patients experienced progressive disease, whereas 2 patients had stable disease throughout the trial period, 1 of them with regression of multiple skin metastases. The remaining 5 patients had no measurable disease. Melan-A/Mart-1 specific CD8 T cells were analyzed ex vivo, with positive results in 6 of 14 evaluable patients. Increased percentages of T cells were found in three patients, memory/effector T cell differentiation in 4 patients, and a positive interferon-gamma Elispot assay in 1 patient. Antibody responses to P40 were observed in all patients. We conclude that vaccination with peptide and P40 was feasible and induced ex vivo detectable tumor antigen specific T cell responses in 6 of 14 patients with advanced melanoma.


Subject(s)
CD8-Positive T-Lymphocytes/metabolism , Cancer Vaccines , HLA-A Antigens/metabolism , Klebsiella pneumoniae/immunology , Melanoma/immunology , Melanoma/therapy , Skin Neoplasms/immunology , Skin Neoplasms/therapy , Adjuvants, Immunologic/administration & dosage , Adult , Aged , Aged, 80 and over , Antigens, Neoplasm/administration & dosage , Bacterial Outer Membrane Proteins/administration & dosage , CD8-Positive T-Lymphocytes/pathology , Female , HLA-A2 Antigen , Humans , MART-1 Antigen , Male , Melanoma/pathology , Melanoma/physiopathology , Middle Aged , Neoplasm Proteins/administration & dosage , Neoplasm Staging , Peptide Fragments/administration & dosage , Skin Neoplasms/pathology , Skin Neoplasms/physiopathology
11.
J Am Acad Dermatol ; 56(5): 835-47, 2007 May.
Article in English | MEDLINE | ID: mdl-17320240

ABSTRACT

Longitudinal pigmentation of the nail is very common. The differential diagnosis varies from subungual hematoma, to a fungal infection, to a melanocytic lesion (lentigo, nevus melanoma, etc.) to others. Often, dermatologists do not feel at ease with these pathologies and management is often not clear. In many cases, a biopsy is not helpful because an inadequate technique was chosen. The use of noninvasive techniques such as dermoscopy has been described to be useful for the preoperative evaluation and the management decision. Using these technique, one will be able to reduce the number of unnecessary surgeries and to choose the most adequate biopsy technique. In this article, we will review the management, including diagnosis as well as differential diagnosis of nail pigmentations and propose a new algorithm for the non invasive diagnosis of nail pigmentation.


Subject(s)
Nail Diseases/diagnosis , Pigmentation Disorders/diagnosis , Biopsy , Dermoscopy , Diagnosis, Differential , Humans , Nail Diseases/surgery , Pigmentation Disorders/surgery , Skin Pigmentation/physiology
12.
J Invest Dermatol ; 127(3): 622-9, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17039243

ABSTRACT

Tumor antigen-specific cytotoxic T cells (CTLs) play a major role in the adaptive immune response to cancers. This CTL response is often insufficient because of functional impairment, tumor escape mechanisms, or inhibitory tumor microenvironment. However, little is known about the fate of given tumor-specific CTL clones in cancer patients. Studies in patients with favorable outcomes may be very informative. In this longitudinal study, we tracked, quantified, and characterized functionally defined antigen-specific T-cell clones ex vivo, in peripheral blood and at tumor sites, in two long-term melanoma survivors. MAGE-A10-specific CD8+ T-cell clones with high avidity to antigenic peptide and tumor lytic capabilities persisted in peripheral blood over more than 10 years, with quantitative variations correlating with the clinical course. These clones were also found in emerging metastases, and, in one patient, circulating clonal T cells displayed a fully differentiated effector phenotype at the time of relapse. Longevity, tumor homing, differentiation phenotype, and quantitative adaptation to the disease phases suggest the contribution of the tracked tumor-reactive clones in the tumor control of these long-term metastatic survivor patients. Focusing research on patients with favorable outcomes may help to identify parameters that are crucial for an efficient antitumor response and to optimize cancer immunotherapy.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , Melanoma/immunology , Antigens, Neoplasm/immunology , Cell Differentiation , Disease Progression , Flow Cytometry , Humans , Immunotherapy , Leukocytes, Mononuclear/cytology , Male , Melanoma/blood , Middle Aged , Neoplasm Metastasis , Neoplasm Proteins/immunology , Phenotype , Time Factors , Treatment Outcome
13.
Blood ; 109(1): 331-8, 2007 Jan 01.
Article in English | MEDLINE | ID: mdl-17190854

ABSTRACT

A PRoliferation-Inducing TNF Ligand (APRIL) costimulates B-cell activation. When overexpressed in mice, APRIL induces B-cell neoplasia, reminiscent of human B-cell chronic lymphoid leukemia (B-CLL). We analyzed APRIL expression in situ in human non-Hodgkin lymphomas. APRIL up-regulation was only observed in high-grade B-cell lymphomas, diffuse large B-cell lymphoma (DLBCL), and Burkitt lymphoma (BL). Up-regulation was seen in 46% and 20% of DLBCL and BL, respectively. In DLBCL, neutrophils, constitutively producing APRIL and infiltrating the tumor tissue, were the main cellular source of APRIL. Rare DLBCL cases showed a predominance of histiocytes or mesenchymal cells as APRIL source. APRIL secreted by neutrophils accumulated on tumor cells via proteoglycan binding. In addition to proteoglycans, DLBCL tumor cells expressed the APRIL signaling receptor, TACI and/or BCMA, indicating that these tumor cells are fully equipped to respond to APRIL. A retrospective clinical analysis revealed a significant correlation between high expression of APRIL in tumor lesions and decreased overall patient survival rate. Hence, APRIL produced by inflammatory cells infiltrating lymphoma lesions may increase tumor aggressiveness and affect disease outcome.


Subject(s)
Burkitt Lymphoma/metabolism , Lymphoma, B-Cell/metabolism , Lymphoma, Large B-Cell, Diffuse/metabolism , Lymphoma, Non-Hodgkin/metabolism , Neoplasm Proteins/physiology , Neutrophils/metabolism , Proteoglycans/metabolism , Tumor Necrosis Factor Ligand Superfamily Member 13/physiology , B-Cell Maturation Antigen/metabolism , Burkitt Lymphoma/mortality , Burkitt Lymphoma/pathology , Gene Expression Regulation, Neoplastic , Humans , Kaplan-Meier Estimate , Lymphoma, B-Cell/mortality , Lymphoma, B-Cell/pathology , Lymphoma, Large B-Cell, Diffuse/mortality , Lymphoma, Large B-Cell, Diffuse/pathology , Lymphoma, Non-Hodgkin/mortality , Lymphoma, Non-Hodgkin/pathology , Neoplasm Invasiveness , Neoplasm Proteins/biosynthesis , Neoplasm Proteins/genetics , Prognosis , Protein Structure, Tertiary , Retrospective Studies , Survival Analysis , Transmembrane Activator and CAML Interactor Protein/metabolism , Tumor Necrosis Factor Ligand Superfamily Member 13/biosynthesis , Tumor Necrosis Factor Ligand Superfamily Member 13/genetics , Up-Regulation
14.
J Immunother ; 28(3): 252-7, 2005.
Article in English | MEDLINE | ID: mdl-15838382

ABSTRACT

Spontaneous immune responses to the cancer testis antigen NY-ESO-1 are frequently found in cancer patients bearing antigen-expressing tumors. In HLA-A2-expressing patients, naturally elicited NY-ESO-1-specific, tumor-reactive cytotoxic T lymphocytes (CTLs) are mostly directed against an immunodominant epitope corresponding to peptide NY-ESO-1 157-165. NY-ESO-1-specific CTLs can also be induced by synthetic peptide vaccines, but they are heterogeneous in terms of functional avidity and tumor reactivity. The authors investigated the structural bases of this phenomenon by analyzing the TCR features of natural and vaccine-induced NY-ESO-1-specific CTLs. The results indicate that CTLs from the two groups exhibit highly structurally conserved but distinct TCR features, suggesting that the synthetic peptides used for vaccination may fail to faithfully mimic the naturally processed antigen. Together, the results of this study underline the strength of TCR molecular monitoring and will be instrumental for the development and monitoring of vaccines aimed at eliciting CTLs with high tumor reactivity.


Subject(s)
Antigens, Neoplasm/immunology , Cancer Vaccines/immunology , Neoplasm Proteins/immunology , Peptide Fragments/immunology , Receptors, Antigen, T-Cell/chemistry , T-Lymphocytes, Cytotoxic/immunology , Amino Acid Sequence , Humans , Molecular Sequence Data , Vaccines, Subunit/immunology
15.
Cancer Res ; 64(17): 6319-26, 2004 Sep 01.
Article in English | MEDLINE | ID: mdl-15342421

ABSTRACT

Tumor-reactive T cells play an important role in cancer immunosurveillance. Applying the multimer technology, we report here an unexpected high frequency of Melan-A-specific CTLs in a melanoma patient with progressive lymph node metastases, consisting of 18 and 12.8% of total peripheral blood and tumor-infiltrating CD8+ T cells, respectively. Melan-A-specific CTLs revealed a high cytolytic activity against allogeneic Melan-A-expressing target cells but failed to kill the autologous tumor cells. Loading of the tumor cells with Melan-A peptide reversed the resistance to killing, suggesting impaired function of the MHC class I antigen processing and presentation pathway. Mutations of the coding region of the HLA-A2 binding Melan-A26-35 peptide or down-regulation of the MHC class I heavy chain, the antigenic peptide TAP, and tapasin could be excluded. However, PCR and immunohistochemical analysis revealed a deficiency of the immunoproteasomes low molecular weight protein 2 and low molecular weight protein 7 in the primary tumor cells, which affects the quantity and quality of generated T-cell epitopes and might explain the resistance to killing. This is supported by our data, demonstrating that the resistance to killing can be partially reversed by pre-exposure of the tumor cells to IFN-gamma, which is known to induce the immunoproteasomes. Overall, this is the first report of an extremely high frequency of tumor-specific CTLs that exhibit competent T-cell-effector functions but fail to lyse the autologous tumor cells. Immunotherapeutic approaches should not only focus on the induction of a robust antitumor immune response, but should also have to target tumor immune escape mechanisms.


Subject(s)
Cysteine Endopeptidases/deficiency , Cysteine Endopeptidases/immunology , Melanoma/immunology , Multienzyme Complexes/immunology , Neoplasm Proteins/immunology , T-Lymphocytes, Cytotoxic/immunology , Antigens, Neoplasm , Cysteine Endopeptidases/genetics , HLA-A2 Antigen/genetics , HLA-A2 Antigen/immunology , Humans , Lymph Nodes/immunology , Lymph Nodes/pathology , MART-1 Antigen , Male , Middle Aged , Multienzyme Complexes/deficiency , Multienzyme Complexes/genetics , Mutation , Proteasome Endopeptidase Complex
16.
Cancer Res ; 64(4): 1496-501, 2004 Feb 15.
Article in English | MEDLINE | ID: mdl-14973052

ABSTRACT

Tumor antigen-reactive T cells can be detected in a large proportion of melanoma patients, but their efficacy on tumor control in vivo remains unclear. On the other hand, vitiligo, a skin disorder characterized by patchy depigmented macules, may occur spontaneously or after antitumor therapies. Moreover, vitiligo is significantly associated with positive clinical response, but the mechanism is not understood. Therefore, the establishment of a relevant animal model in which melanoma and vitiligo spontaneously develop stepwise may be useful for better understanding of the parameters involved in the destruction of both benign and malignant melanocytes. In a previous work, we established a mouse model for melanoma in which MT/ret transgenic mice express the ret oncogene fused to the metallothionein promoter. Here we report that melanoma leads to spontaneous vitiligo. We further investigate, for the first time in this model, the natural antitumor T-cell response and evaluate the role of cellular immunity in the development of the disease. Interestingly, the occurrence of spontaneous tumor nodules in MT/ret mice with melanoma-associated vitiligo is significantly delayed when compared in melanoma mice without vitiligo. Moreover, a significant proportion of mice with melanoma-associated vitiligo resisted a challenge with syngeneic melanoma cells in contrast to animals without vitiligo. Our results confirm that vitiligo is associated with clinical benefit and further demonstrate the crucial role of CD8+ T cells for tumor control in melanoma-associated vitiligo.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , Disease Models, Animal , Melanoma/immunology , Vitiligo/etiology , Animals , Interferon-gamma/biosynthesis , Metals, Heavy/toxicity , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Transgenic , Oncogene Proteins/genetics , Proto-Oncogene Proteins c-ret , Receptor Protein-Tyrosine Kinases/genetics
17.
J Immunol ; 172(5): 2773-7, 2004 Mar 01.
Article in English | MEDLINE | ID: mdl-14978076

ABSTRACT

Functionally naive CD8 T cells in peripheral blood from adult humans can be fully described by their CD45RA(bright)CCR7(+)CD62L(+) cell surface phenotype. Cord blood lymphocytes, from healthy newborns, are homogenously functionally naive. Accordingly, the majority of cord blood CD8 T cells express the same pattern of cell surface molecules. Unexpectedly, however, a significant fraction of cord blood CD8 T cells express neither CCR7 nor CD62L. Yet these cells remain functionally naive as they contain high levels of TCR excision circles, have long telomeres, display highly polyclonal TCRs, and do not exhibit immediate effector functions. In addition, these CD8 T cells already represent a significant fraction of the mature naive CD8 single-positive thymocyte repertoire and may selectively express the cutaneous lymphocyte Ag. We suggest that CD8 single-positive thymocytes comprise two pools of naive precursors that exhibit distinct homing properties. Once seeded in the periphery, naive CCR7(+)CD62L(+) CD8 T cells patrol secondary lymphoid organs, whereas naive CCR7(-)CD62L(-) CD8 T cells selectively migrate to peripheral tissues such as skin.


Subject(s)
CD8-Positive T-Lymphocytes/cytology , CD8-Positive T-Lymphocytes/immunology , Cell Movement/immunology , Interphase/immunology , Skin/cytology , Skin/immunology , Thymus Gland/cytology , Thymus Gland/immunology , CD8-Positive T-Lymphocytes/metabolism , Cell Division/immunology , Child , Child, Preschool , Fetal Blood/cytology , Fetal Blood/immunology , Fetal Blood/metabolism , Humans , Immunophenotyping , Infant , Infant, Newborn , Receptors, Antigen, T-Cell, alpha-beta/biosynthesis , Receptors, CCR7 , Receptors, Chemokine/biosynthesis , Receptors, Chemokine/blood , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism , Thymus Gland/metabolism
18.
J Immunol Methods ; 280(1-2): 103-11, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12972191

ABSTRACT

We described a new process for the design of HLA tetramers using soluble MHC class I molecules purified from Epstein Barr Virus-transformed B cells. This method does not rely on genetic engineering and presents a significant advantage in view of the polymorphism of MHC class I molecules because tetramers can be produced with any HLA molecule. Here, we showed that our HLA-A*0201 tetramers provided experimental results similar to those obtained with tetramers made with recombinant MHC molecules. Moreover, they can be used to efficiently identify peptide-specific T cells from ex vivo PBMCs as well as from lymphocytes infiltrating human tumor. This innovative and simple method could be widely adopted, specially in diagnostic procedures for monitoring peptide-based immunotherapy.


Subject(s)
HLA-A Antigens/chemistry , Immunologic Techniques , Lymphocytes, Tumor-Infiltrating/immunology , Amino Acid Sequence , Antigen Presentation , Cell Line , HIV Infections/immunology , HLA-A Antigens/isolation & purification , HLA-A2 Antigen , Humans , In Vitro Techniques , Melanoma/immunology , Oligopeptides/chemistry , Oligopeptides/immunology , Protein Structure, Quaternary , T-Lymphocytes/immunology
19.
J Immunol ; 170(10): 5103-9, 2003 May 15.
Article in English | MEDLINE | ID: mdl-12734356

ABSTRACT

The specificity of recognition of pMHC complexes by T lymphocytes is determined by the V regions of the TCR alpha- and beta-chains. Recent experimental evidence has suggested that Ag-specific TCR repertoires may exhibit a more V alpha- than V beta-restricted usage. Whether V alpha usage is narrowed during immune responses to Ag or if, on the contrary, restricted V alpha usage is already defined at the early stages of TCR repertoire selection, however, has remained unexplored. Here, we analyzed V and CDR3 TCR regions of single circulating naive T cells specifically detected ex vivo and isolated with HLA-A2/melan-A peptide multimers. Similarly to what was previously observed for melan-A-specific Ag-experienced T cells, we found a relatively wide V beta usage, but a preferential V alpha 2.1 usage. Restricted V alpha 2.1 usage was also found among single CD8(+) A2/melan-A multimer(+) thymocytes, indicating that V alpha-restricted selection takes place in the thymus. V alpha 2.1 usage, however, was independent from functional avidity of Ag recognition. Thus, interaction of the pMHC complex with selected V alpha-chains contributes to set the broad Ag specificity, as underlined by preferential binding of A2/melan-A multimers to V alpha 2.1-bearing TCRs, whereas functional outcomes result from the sum of these with other interactions between pMHC complex and TCR.


Subject(s)
Autoantigens/immunology , Epitopes, T-Lymphocyte/immunology , Gene Rearrangement, alpha-Chain T-Cell Antigen Receptor/physiology , HLA-A2 Antigen/immunology , Melanoma/immunology , Neoplasm Proteins/immunology , Receptors, Antigen, T-Cell, alpha-beta/physiology , Amino Acid Sequence , Antigens, Neoplasm , Autoantigens/genetics , Autoantigens/metabolism , Cell Differentiation/genetics , Cell Differentiation/immunology , Clone Cells , Cytotoxicity, Immunologic/genetics , Epitopes, T-Lymphocyte/biosynthesis , Epitopes, T-Lymphocyte/genetics , Epitopes, T-Lymphocyte/metabolism , Gene Rearrangement, beta-Chain T-Cell Antigen Receptor/physiology , HLA-A2 Antigen/biosynthesis , HLA-A2 Antigen/genetics , HLA-A2 Antigen/metabolism , Hematopoietic Stem Cells/immunology , Hematopoietic Stem Cells/metabolism , Humans , MART-1 Antigen , Melanoma/genetics , Molecular Sequence Data , Neoplasm Proteins/genetics , Neoplasm Proteins/metabolism , RNA, Messenger/analysis , Receptors, Antigen, T-Cell, alpha-beta/biosynthesis , Receptors, Antigen, T-Cell, alpha-beta/genetics , Reverse Transcriptase Polymerase Chain Reaction , T-Lymphocytes, Cytotoxic/immunology , T-Lymphocytes, Cytotoxic/metabolism , Tumor Cells, Cultured
20.
Int J Cancer ; 98(2): 221-7, 2002 Mar 10.
Article in English | MEDLINE | ID: mdl-11857412

ABSTRACT

Identification of tumor antigens and their optimal antigenic peptides raised hopes for the development of peptide-based immunotherapeutic vaccine strategies for human melanoma, however. Synthetic peptides alone are not immunogenic enough, and adequate formulation is critical for elaboration of peptide vaccines. To improve formulation, we evaluated 2 lipopeptide constructs, both including HLA-A2-restricted MART 27-35-CD8+ T lymphocyte (CTL) epitope covalently linked to universal tetanus toxoid (TT) 830-843 helper T lymphocyte (HTL) epitope, in HLA-A2 transgenic mouse models that mimic human CTL responses in vivo. These 2 constructs only differed in the formulation of their lipid tail. We showed that lipopeptide constructs were strongly recognized, in vitro, by human MART 27-35 cytotoxic T cells derived from tumor-infiltrating lymphocytes. The transgenic Mice immunized with these 2 MART lipopeptide formulations containing covalently linked HTL-CTL epitopes induced strong MART 27-35 cytotoxic T cells. This CTL induction was critically dependent on the presence of the helper T lymphocyte epitope. These results also showed that a single palmitoyl-lysine chain is enough to assure immunogenicity of a given peptide and that the presence of a lipid tail bypass the need for adjuvant. These results support the selection of MART-lipopeptide melanoma vaccine for evaluation in a clinical trial.


Subject(s)
Cancer Vaccines/immunology , Epitopes/immunology , Melanoma, Experimental/immunology , Neoplasm Proteins/immunology , T-Lymphocytes, Cytotoxic/immunology , Adjuvants, Immunologic/pharmacology , Amino Acid Sequence , Animals , Cell Line , Cells, Cultured , Cytotoxicity Tests, Immunologic , Epitopes/chemistry , HLA-A2 Antigen/genetics , Lipoproteins/chemistry , Lipoproteins/immunology , Melanoma, Experimental/therapy , Mice , Mice, Transgenic , Neoplasm Proteins/chemistry , Peptide Fragments/immunology , T-Lymphocytes, Helper-Inducer/immunology , Tetanus Toxoid/immunology , Tumor Cells, Cultured
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