Search results for "Melanoma-Specific Antigens"
showing 9 items of 9 documents
Residual tumor micro-foci and overwhelming regulatory T lymphocyte infiltration are the causes of bladder cancer recurrence
2016
Bladder cancer has an unexplained, high recurrence rate. Causes of recurrence might include the presence of sporadic tumor micro-foci in the residual urothelial tissue after surgery associated with an inverted ratio between intratumoral effector and regulatory T cell subsets. Hence, surgical specimens of both tumors and autologous, macroscopically/histologically free-of-tumor tissues were collected from 28 and 20 patients affected by bladder or renal cancer, respectively. The frequencies of effector (IFNγ+ and IL17+ T cells) and regulatory (CD4+CD25hiCD127lo and CD8+CD28-CD127loCD39+ Treg) T cell subpopulations among tumor infiltrating lymphocytes were analyzed by immunofluorescence, while …
Primary oral melanoma : a histopathological and immunohistochemical study of 22 cases of Latin America
2011
Objective: The aim of this study was to analyze the histopathological and immunohistochemical characteristics of 22 cases of primary oral melanomas (OM). Study Design: Twenty two cases of primary oral melanoma were analyzed by description of their histopathological features and immunohistochemical study using the antibodies S-100, HMB-45, Melan-A and Ki-67. Results: The mean age was 58 years and 14 cases were female. The main affected sites were the hard palate, followed by the upper gingiva. Microscopically, 15 cases presented level III of invasion, 2 cases were amelanotic and 13 showed a mixed epithelioid and plasmacytoid or spindle cells composition. Some cases showed necrosis, perivascu…
Generation of cytotoxic T-cell responses with synthetic melanoma-associated peptidesin vivo: Implications for tumor vaccines with melanoma-associated…
1996
Peptide epitopes derived from differentiation antigens of the melanocyte lineage have been identified in human melanomas and normal cultured melanocytes as targets for MHC-restricted cytotoxic T lymphocytes (CTL). Characterization of multiple CTL-defined antigenic determinants and the presence of corresponding precursor CTL open perspectives for the development of antigen-based vaccines. In the present study, we determined the CTL reactivity against melanoma-associated peptides derived from Melan A/MART-1, tyrosinase and gp100/Pmel17 in 10 HLA-A2+ melanoma patients and 10 healthy individuals. Then, we examined the immunological effects and toxicity of intradermal inoculation of synthetic me…
A comparison of two types of dendritic cell as adjuvants for the induction of melanoma-specific T-cell responses in humans following intranodal injec…
2001
Dendritic cells (DCs) elicit potent anti-tumoral T-cell responses in vitro and in vivo. However, different types of DC have yet to be compared for their capacity to induce anti-tumor responses in vivo at different developmental stages. Herein, we correlated the efficiencies of different types of monocyte-derived DC as vaccines on the resulting anti-tumor immune responses in vivo. Immature and mature DCs were separately pulsed with a peptide derived from tyrosinase, MelanA/MART-1 or MAGE-1 and a recall antigen. Both DC populations were injected every 2 weeks in different lymph nodes of the same patient. Immune responses were monitored before, during and after vaccination. Mature DCs induced …
Clonal expansion of melan a-specific cytotoxic T lymphocytes in a melanoma patient responding to continued immunization with melanoma-associated pept…
2000
Peptides derived from human tumor antigens have been used in a number of clinical trials to induce specific immune responses against autologous tumors in cancer patients. Although favorable clinical results were observed in single patients, immune responses correlating with tumor regression were either not detected or in case of responses, the T-cell specificity was difficult to demonstrate. In this study, we analyzed antigen-specific T-cell responses induced in the skin and in peripheral blood lymphocytes (PBL) in an HLA-A2-positive melanoma patient. The patient showed major regression of metastatic melanoma under continued immunization with peptides derived from the melanocyte differentia…
A gene encoding an antigen recognized by cytolytic T lymphocytes on a human melanoma.
1991
Many human melanoma tumors express antigens that are recognized in vitro by cytolytic T lymphocytes (CTLs) derived from the tumor-bearing patient. A gene was identified that directed the expression of antigen MZ2-E on a human melanoma cell line. This gene shows no similarity to known sequences and belongs to a family of at least three genes. It is expressed by the original melanoma cells, other melanoma cell lines, and by some tumor cells of other histological types. No expression was observed in a panel of normal tissues. Antigen MZ2-E appears to be presented by HLA-A1; anti-MZ2-E CTLs of the original patient recognized two melanoma cell lines of other HLA-A1 patients that expressed the ge…
Granulocyte-macrophage-colony-stimulating factor enhances immune responses to melanoma-associated peptides in vivo.
1996
Peptide epitopes derived from differentiation antigens of the melanocyte lineage were recently identified in human melanomas as targets for MHC-restricted cytotoxic T lymphocytes (CTL). The characterization of multiple CTL-defined antigenic determinants has opened possibilities of development of antigen-targeted vaccines. In the present study, we determined CTL reactivity against melanoma-associated peptides derived from Melan A/MART-1, tyrosinase, and gp100/Pmel17 in 3 HLA-A2+ melanoma patients. Then, we assessed the immune responses to synthetic melanoma-associated peptides injected intradermally. After 3 cycles of immunization with peptide alone, we used systemic GM-CSF as an adjuvant du…
Erythrophagocytic tumour cells in melanoma and squamous cell carcinoma of the skin
1997
Aims: Erythrophagocytosis is a characteristic feature of tumour cells in malignant histiocytosis, some leukaemias, lymphomas, and also reactive histiocytes in the haemophagocytic syndrome associated with a variety of infections and neoplasms. It has also been found exceptionally in metastatic malignant epithelial cells in bone marrow and lymph nodes. We present two cases, a cutaneous malignant melanoma and an acantholytic squamous cell carcinoma, in which erythrophagocytosis by tumour cells was demonstrable by both light and electron microscopy. Methods and results: The melanocytic and squamous nature of these cells was supported by the immunohistochemical detection of HMB45, S100, and NKI-…
Primary malignant melanoma of the oral cavity: case report.
2002
An 80-year-old-female patient had a pigmented lesion on: the hard palate, the soft palate, the alveolar mucosa and the vestibolar mucosa of the maxillary gingiva. Pigmented macules and patchs had been persistent and asymptomatic for many years (Fig. 1). The lesion exhibited irregularities of pigmentation, border and surface contour. About 1 year later the patient had noticed an extension of the pigmented macules and plaques; there was also the appearance of nodules of the maxillary gingiva accompanied by swelling. Loosening of teeth as a result of extensive destruction of bone was further noted (Fig. 2). Figure 1. Pigmented macules and patchs with irregularities of pigmentation, border and …