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M Bagot

Publications and source records attributed to M Bagot.

At least 55 records · Page 3Linked to original sources
PubMed2000

Functional inhibitory receptors expressed by a cutaneous T cell lymphoma-specific cytolytic clonal T cell population.

Inhibitory receptors on natural killer cells and on a minority of T lymphocytes are major histocompatibility complex class Ia or Ib specific. We have previously reported several tumor-specific cytotoxic T cell clones infiltrating a CD4(+) V beta 13(+) cutaneous T cell lymphoma. These clones mediated a specific major histocompatibility complex class I-restricted cytotoxic activity toward the uncultured tumor cells and autologous long-term tumor T cell lines. In this study, we cultured with interleukin-2 the peripheral blood lymphocytes of the same patient a few weeks before invasion of the blood by tumor cells. We report the rapid and selective expansion of a CD8(+) V beta 13(+) lymphoid population. This population was clonal, as it expressed a unique T cell receptor-V beta junctional region. V beta 13(+) tumor cells and V beta 13(+) reactive T cells were shown to have different junctional sequences. The CD8(+) reactive clone was functional, as it had a specific autologous tumor-specific, human leukocyte antigen-A2 restricted, cytotoxic activity. This clone coexpressed high levels of CD158a, CD158b, p70, and CD94/NKG2A inhibitory receptors. Interestingly, we found that anti-CD158a and anti-CD158b monoclonal antibodies could inhibit anti-CD3 redirected cytotoxicity mediated by the reactive clonal population. Further, an anti-human leukocyte antigen-B/C monoclonal antibody enhanced the specific cytotoxic activity of the clone against autologous tumor cells. These results are the first evidence that inhibitory receptor expression can lead to the inhibition of cutaneous T cell lymphoma-specific T cell responses.

Aged↗
PubMed2000

Cutaneous T cell lymphoma reactive CD4+ cytotoxic T lymphocyte clones display a Th1 cytokine profile and use a fas-independent pathway for specific tumor cell lysis.

We have previously described two cytotoxic T lymphocyte clones isolated from lymphocytes infiltrating a human major histocompatibility complex class II-/class I+, CD4+ cutaneous T cell lymphoma. These clones displayed a CD4+CD8dim+ (TC5) and CD4+ CD8- (TC7) phenotype and mediated a specific major histocompatibility complex class I-restricted cytotoxic activity toward Cou-LB autologous tumor cell line. Our studies were performed to elucidate the mechanism involved in T-cell-clone-mediated cytotoxicity and to determine the cytokine profile of both the lymphoma cell line and specific cytotoxic T lymphocyte clones. The results indicate that, despite surface expression of Fas receptor on Cou-LB and Fas ligand induction on TC5 and TC7 cell membranes, the CD4+ cytotoxic T lymphocyte clones do not use this cytotoxic mechanism to lyse their specific target. The TC7 clone uses instead a granzyme-perforin-dependent pathway. Furthermore, quantitative analysis of Th1 and Th2 cytokine mRNA expression in the cutaneous T cell lymphoma cell line as well as in TC5 and TC7 clones indicated that, whereas the tumor cells display a Th2-type profile (interleukin-4, interleukin-6, and interleukin-10), the cytotoxic T lymphocyte clones express Th1-type cytokines (interferon-gamma, granulocyte macrophage colony stimulating factor, and interleukin-2). In addition, preincubation of the tumor-infiltrating lymphocyte clones with autologous tumor cells induced their activation and subsequent amplification of the Th1-type response. These results indicate a direct contribution of the malignant cells in the Th1/Th2 imbalance observed frequently in cutaneous T cell lymphoma patients and suggest their potential role in depressed cell-mediated immunity. Identification of CD4+ Th1-type cytotoxic T lymphocyte clones, the tumor antigen they recognize, and optimization of their cytokine expression profile should be useful for the design of new immunotherapy protocols in cutaneous T cell lymphoma.

Aged↗
PubMed1999

[Contribution of immunotherapy to the treatment of T-cell lymphoma of the skin].

DEFINITION: T-cell lymphomas localized predominantly or primarily in skin comprise a heterogeneous group of tumors. The most frequent is fungoid mycosis. T-CELL TUMORS AND GROWTH FACTORS: When growth factors of T-cell tumors, particularly IL-7 and IL-5, were identified, it became possible to grow T-cell tumoral clones in long-term in vitro cultures used to evidence anti-tumoral cellular immune reactions in T-cell skin cancers. Reactional T-cell clones with specific anti-tumoral reactions can be expaned ex vivo. This advance has made it possible to identify tumoral antigens and better understand the mechanisms leading to tumoral escape from anti-tumoral defense systems. THERAPEUTIC PERSPECTIVES: It is now possible to develop immunotherapy strategies based on reinjection of T lymphocytes with specific cytotoxic activity after ex vivo expansion. Injections of immunogenic peptides associated or not with dendritic cells or injection of DNA coding for these tumor antigens are other possibilities.

Growth Substances↗
PubMed1999

Prognostic factors in primary cutaneous lymphomas other than mycosis fungoides and the Sézary syndrome. The French Study Group on Cutaneous Lymphomas.

Prognostic studies of primary cutaneous lymphomas (PCL) other than mycosis fungoides (MF) and the Sézary syndrome (SS; non-MF/SS PCL) have been mainly performed on subgroups or on small numbers of patients by using univariate analyses. Our aim was to identify independent prognostic factors in a large series of patients with non-MF/SS PCL. We evaluated 158 patients who were registered in the French Study Group on Cutaneous Lymphomas database from January 1, 1986 to March 1, 1997. Variables analyzed for prognostic value were: age; sex; type of clinical lesions; maximum diameter, location, and number of skin lesions; cutaneous distribution (ie, local, regional, or generalized); prognostic group according to the European Organization for Research and Treatment of Cancer (EORTC) classification for PCL; B- or T-cell phenotype; serum lactate dehydrogenase (LDH) level; and B symptoms. Univariate and multivariate analyses were performed using a model of relative survival. Forty-nine patients (31%) died. The median relative survival time was 81 months. In univariate analysis, EORTC prognostic group, serum LDH level, B symptoms, and variables related to tumor extension (ie, distribution, maximum diameter, and number of skin lesions) were significantly associated with survival. When these variables were considered together in a multivariate analysis, EORTC prognostic group and distribution of skin lesions remained statistically significant, independent prognostic factors. This study confirms the good predictive value of the EORTC classification for PCL and shows that the distribution of skin lesions at initial evaluation is an important prognostic indicator.

Adolescent↗
PubMed1999

A prospective study of cutaneous intolerance to topical mechlorethamine therapy in patients with cutaneous T-cell lymphomas. French Study Group of Cutaneous Lymphomas.

OBJECTIVE: To study the exact frequency and the histological features of cutaneous intolerance to mechlorethamine (CIM) hydrochloride therapy in patients with cutaneous T-cell lymphomas, including Langerhans cell histiocytosis. DESIGN: A multicenter prospective study was conducted from January 1, 1994, to May 31, 1996, in 12 different hospitals in France. PATIENTS: Of the 52 patients with cutaneous T-cell lymphomas or Langerhans cell histiocytosis, 35 were men and 17 were women, aged 18 to 87 years. Of the 52 patients, 35 had mycosis fungoides, 8 had nonepidermotropic cutaneous lymphoma, 7 had lymphomatoid papulosis, 1 had Sézary syndrome, and 1 had Langerhans cell histiocytosis. METHODS: Patients were treated with topical applications of a 0.02% aqueous solution of mechlorethamine. The diagnosis of CIM was determined by the presence of erythema and pruritus. Patients who developed CIM underwent closed patch testing with three 10-fold dilutions of 0.02% mechlorethamine solution. A positive patch test result was the presence of erythema and pruritus, a weak result was the presence of simple erythema without pruritus, and a negative result was the absence of erythema and pruritus. Skin biopsy specimens from patients with positive patch test results were obtained in patients who developed CIM. The biopsy specimens were reviewed, and the results determined by 2 pathologists (E.T. and J.W.). The histopathological findings were classified in 3 categories: (1) spongiotic dermatitis, (2) irritant dermatitis, and (3) insignificant or normal. In September 1998, the referring physicians were contacted if mechlorethamine therapy had been continued in patients with CIM. RESULTS: Of the 52 patients, 43 were evaluated for tolerance to mechlorethamine therapy. Of the 43 patients, CIM developed in 23, from 4 days to 9 months after the initiation of mechlorethamine therapy. Of those 23 patients, CIM developed within 3 months in 21 and within 1 month in 13. Closed patch tests were performed in 21 of the 23 patients who developed CIM. The results of the patch test were positive in 12, weak in 4, and negative in 5. Of these 21 patients, 14 skin biopsy specimens were obtained in 14 different patients who had positive or weak patch test results. The specimens showed histological features that were consistent with spongiotic dermatitis in 9 patients, irritant dermatitis in 2, and insignificant or normal in 3. All 9 patients with histological features of spongiotic dermatitis discontinued mechlorethamine therapy. All 5 patients without histological features of spongiotic dermatitis were able to resume mechlorethamine therapy. These results do not correlate with those of previous study results. CONCLUSIONS: Mechlorethamine therapy is a cost-effective and easily administered treatment for cutaneous T-cell lymphomas. Our study shows that allergic dermatitis caused by mechlorethamine therapy is an early and frequent adverse reaction in patients with cutaneous T-cell lymphomas. The most common histological feature of patients with CIM is spongiotic dermatitis.

Administration, Cutaneous↗
PubMed1999

Polymerase chain reaction analysis of immunoglobulin gene rearrangement in cutaneous lymphoid hyperplasias. French Study Group for Cutaneous Lymphomas.

UNLABELLED: The differential diagnosis of cutaneous lymphoid hyperplasia and B-cell lymphoma may be difficult. Whether the detection of clonal immunoglobulin gene rearrangement in the cutaneous lesion is predictive of a malignant outcome remains controversial. We therefore studied cases of cutaneous lymphoid hyperplasia by polymerase chain reaction analysis. DESIGN: Retrospective study of patients seen between 1988 and 1996. SETTING: Two dermatology university departments. PATIENTS: Twenty-four patients with cutaneous lymphoid hyperplasias were included according to clinical, histopathological, and immunophenotypic criteria. MAIN OUTCOME MEASURES: Clinical, histopathological, and laboratory findings. RESULTS: There were 13 men and 11 women (mean age, 49 years) who presented with erythematous or violaceous papules or nodules. The lesions were unique in 13 cases and multiple in 11 cases. All patients had immunochemical evidence of a mixed T- and B-cell infiltrate with polytypic B cells. Polyclonality was demonstrated in 23 patients, whereas a dominant B-cell clone was detected in 1 patient. No lymphoma developed during the follow-up (median, 4 years). In the same period, we studied 53 cases of B-cell lymphomas. Thirty-five (66%) of the 53 cases had a detectable clonal immunoglobulin gene rearrangement. CONCLUSIONS: In the majority of our cases, polyclonality demonstrated by polymerase chain reaction analysis was in accordance with the diagnosis of cutaneous lymphoid hyperplasia. In 1 of the 24 patients, the presence of a B-cell clone could be evidenced. This fact did not modify the treatment as there were no histological or immunophenotypic signs suggestive of a lymphoma.

Female↗
PubMed1999

Pseudoepitheliomatous hyperplasia in cutaneous T-cell lymphoma. A clinical, histopathological and immunohistochemical study with particular interest in epithelial growth factor expression. The French Study Group on Cutaneous Lymphoma.

Pseudoepitheliomatous hyperplasia has occasionally been reported in cutaneous T-cell lymphoma (CTCL). This association raises the question of the relationship between epidermal hyperplasia and the lymphomatous infiltrate. Because epidermal growth factor (EGF) and transforming growth factor-alpha (TGF-alpha) have been demonstrated to be involved in epidermal proliferation through binding to EGF receptor (EGFr), we tested the hypothesis that these cytokines could be secreted by lymphomatous cells, and induce the overlying pseudoepitheliomatous hyperplasia. The purposes of this study were: (i) to describe the clinical and immunohistological features of pseudoepitheliomatous hyperplasia; (ii) to determine its frequency in a large series of CTCLs; and (iii) to evaluate the expression of EGF, TGF-alpha and EGFr in CTCL with or without pseudoepitheliomatous hyperplasia. Eleven cases of CTCL with pseudoepitheliomatous hyperplasia were collected from a series of 353 cases of cutaneous lymphoma registered from 1990 to 1996. They consisted of eight of 28 (28.5%) CD30+ large T-cell lymphomas and three of 148 (2%) cases of mycosis fungoides. Epidermal expression of EGF, EGFr and TGF-alpha was stronger in CTCL than in control normal human skin. Lymphomatous T cells expressed EGF and TGF-alpha whereas no expression of these cytokines could be detected in cutaneous and nodal B-cell lymphomas, nor in a normal lymph node. In addition, epidermal expression of EGFr was stronger in CTCL with pseudoepitheliomatous hyperplasia than in control cases of CTCL without pseudoepitheliomatous hyperplasia, suggesting that these cytokines, in association with other factors, are probably involved in the epidermal hyperplasia observed in some cases of CTCL.

Epidermal Growth Factor↗
PubMed1999

CD4+ CD56+ cutaneous neoplasms: a distinct hematological entity? Groupe Français d'Etude des Lymphomes Cutanés (GFELC).

We report seven cases of particular cutaneous tumors selected from the register of the French Study Group on Cutaneous Lymphomas. The patients (three men, four women) were aged 37-86 years. They initially presented with cutaneous nodules or papules. Three cases presented with regional lymph nodes. Stagings were negative, except for one patient with bone marrow involvement. Histological features were relevant with pleomorphic medium T-cell lymphoma, but these cells exhibited a distinguishing phenotype. They were positive for CD4, CD56, and also CD45, CD43, and HLA-DR. All other T-cell and B-cell markers were negative. The myelomonocytic markers (CD13, CD14, CD15, CD33, CD117, myeloperoxidase, and lysozyme) were negative excepted CD68, which was clearly positive in four cases and weakly in two cases. Others natural killer cell markers (CD16, CD57, TiA1, granzyme B), TdT, and CD34 were negative. Polymerase chain reaction studies did not detect any B or T clonal rearrangement. The cytogenetic studies, performed in five cases, showed a del(5q) in two cases. All patients were treated successfully by polychemotherapy, but relapsed quickly in the skin, between 4 and 28 months. Five patients developed bone marrow involvement, with leukemia in three cases, and they died in 5-27 months. One patient died at 17 months with skin progression. The seventh patient is alive at 33 months, with cutaneous progression. The origin of these cells is unclear. Despite expression of CD4 or CD56, we failed to demonstrate a T-cell, natural killer cell origin. However, CD4 and CD56 are not specific for T or natural killer lineages. Although these two markers are also known to be expressed by monocytic cells, classic myeloid antigens were negative. These seven cases, together with other rare similar cases already reported, seem to represent a distinct entity likely developed from hematological precursor cells.

Adult↗
PubMed1999

The Spectrum of Cutaneous Lymphomas in HIV infection: a study of 21 cases.

We studied 21 HIV-associated lymphomas with cutaneous presentation to determine whether they showed features of primary cutaneous lymphoma arising fortuitously or whether they represented the cutaneous involvement of AIDS systemic lymphoma. Besides rare mycosis fungoides (n = 3), which shared typical clinicopathologic lesions, nonepidermotropic large-cell lymphomas (n = 18) were predominant. They frequently presented as a solitary nodule or tumor. Seven of the eight large T-cell lymphomas had a CD30-positive (CD30+) phenotype but did not express ALK protein. Overexpression of p53 protein was observed in six cases. Although EBV-EBER transcripts were detected in two of them, LMP1 protein was absent. Except for their original prevalence, the features of these T-cell CD30+ cutaneous lymphomas were the same as in immunocompetent patients. The 10 B-cell cutaneous lymphoma were immunoblastic or centroblastic lymphomas, with a differential expression of BCL-6 and Syndecan. Four of them expressed CD30, EBER-EBV transcripts, and LMP1 and p53 proteins. This B-cell CD30+ EBV+ phenotype contrasts with cutaneous lymphoma in immunocompetent patients. Human herpesvirus 8 was not involved in lymphomagenesis since its sequences were detected in a single patient with Kaposi's sarcoma and Castleman's disease. These lymphomas occurred in severely immunocompromised patients with a low CD4 count. Death was due to immunodepression rather than to lymphoma spread, suggesting avoiding aggressive immunosuppressive treatment in such patients.

Adult↗
PubMed1999

[Pilotropic T-cell lymphoma without mucinosis: 5 new cases].

BACKGROUND: Pilotropic cutaneous T-cell lymphomas without mucinosis are rare, with 27 cases previously reported. Diagnosis and classification may be difficult. The clinical course and histopathological and immunohistochemical findings in 5 patients are described. PATIENTS AND METHODS: Patients were selected from the register of the French Study Group for cutaneous lymphomas. The criteria for inclusion were clinical pilofollicular manifestations and histological features of pilotropic T-cell lymphoma without mucinosis. RESULTS: Five patients were selected. The most frequent clinical manifestations were follicular keratosis, alopecia and follicular papules. Typical lesions of mycosis fongoides were present for several years in 3 patients, and lymphomatoid papulosis preexisted in one patient. Histopathological analysis showed an infiltrate composed of CD3+ and CD4+ atypical lymphocytes involving the follicular epithelium with alteration of the hair follicle walls. Epidermotropism was associated with pilotropism and situated near the follicular lesions or farther apart. Alcian blue stains results were negative in all specimens. PCR studies showed the presence of a T-cell clone in the skin lesions in all cases. COMMENTS: Diagnosis of pilotropic cutaneous T cell lymphomas without mucinosis may be difficult in case of discrete epidermotropism, minimal infiltrate or involvement of the follicular epithelium. Pilotropism could define a particular variant of T-cell lymphomas.

Adult↗
PubMed1998

Prognostic significance of a polymerase chain reaction-detectable dominant T-lymphocyte clone in cutaneous lesions of patients with mycosis fungoides.

Although mycosis fungoides (MF) is considered to be an indolent lymphoma, survival is highly influenced by TNM stage. At diagnosis, most MF patients present with early stage disease and a high probability of long-term survival. Treatment is generally directed towards skin lesions, and achievement and duration of complete responses are variable. A dominant T-cell clone is detectable in the cutaneous lesions of 60% of patients. The aim of this study was to determine whether the presence of a T-cell clonal population influences the clinical course of the disease after topical therapy. Cutaneous biopsies from 68 patients were histologically diagnosed as MF and T-cell clonality was analyzed by in vitro amplification of TCR-gamma chain gene rearrangements (polymerase chain reaction gamma [PCRgamma]). After a median follow-up of 48 months, response to treatment was clinically assessed. Age, sex, duration of symptoms before diagnosis, type of cutaneous lesions (T stage), TNM stage, and PCRgamma were evaluated as predictive factors of response to treatment in univariate and multivariate analyses. Univariate analysis demonstrated that T1 cutaneous lesions (P = .05) and PCRgamma negativity (P = .007) were associated with a higher complete remission rate. Using multivariate analysis, T stage (relative risk, 3.13; P = .06) and PCRgamma (relative risk, 4.4; P = .01) remained independent significant predictive parameters of response. In conclusion, T stage and cutaneous PCRgamma at diagnosis are the two predictive parameters of treatment response for MF. Therefore, the cutaneous PCRgamma findings should be considered in the analysis of future therapeutic trials.

Administration, Cutaneous↗
PubMed1998

Isolation of tumor-specific cytotoxic CD4+ and CD4+CD8dim+ T-cell clones infiltrating a cutaneous T-cell lymphoma.

We have isolated several T-cell clones from lymphocytes infiltrating a human major histocompatibility class (MHC) II negative cutaneous T-cell lymphoma (CTCL). We describe here two of these clones, TC5 and TC7, with, respectively, a CD4(+)CD8dim+ and CD4(+)CD8(-) phenotype. Both clones mediated a specific MHC class I-restricted cytotoxic activity toward the fresh autologous tumor cells, and autologous tumor cell lines previously established with interleukin-2 (IL-2) and IL-7 from the skin and from the blood. Analysis of the T-cell receptor (TCR) Vbeta gene expression showed that the tumor cells, which were shown to have a trisomy 7 by fluorescent in situ hybridization, expressed Vbeta7/Jbeta2.3, Vbeta13/Jbeta2.5, and Vbeta22/Jbeta2.5 rearrangements. Phenotypic analysis using specific anti-Vbeta monoclonal antibodies indicated that only Vbeta13 could be detected on the cell membrane of the tumor cells. Analysis of the TCR Vbeta gene expression of the clones showed that TC5 and TC7 expressed a unique TCR-Vbeta transcript, corresponding, respectively, to Vbeta5/Jbeta2.3 and Vbeta17/Jbeta2.7 gene segments. To determine whether these reactive T lymphocytes were present in vivo, we used specific primers corresponding to TC5- and TC7-Vbeta TCR transcripts. The results showed that both cytotoxic T-cell clones were present at the lesional skin site and amplified in vitro. TC7 was found in the patient peripheral blood invaded by tumoral cells, whereas TC5 was not, indicating that the repertoire of the reactional lymphocytes differs in the blood and at the tumor site. These results show for the first time the presence of reactive T lymphocytes with CD4 or double-positive phenotype infiltrating a CTCL. These findings raise the question of the role of these antitumoral effector T cells in the tumor growth.

Aged↗
PubMed1998

Covalent binding of carbamazepine reactive metabolites to P450 isoforms present in the skin.

Carbamazepine is an anticonvulsant associated with a high risk for severe cutaneous reactions. Upon metabolism by cytochrome P450, carbamazepine may produce reactive metabolites. We evaluated in vitro the covalent binding of carbamazepine reactive metabolites on human P450s and then the presence of these P450s in human epidermis. Carbamazepine reactive metabolites covalent binding to human liver microsomes involved P450 subfamilies 1A, 2C and 3A. Specific covalent binding to yeasts expressing different P450s showed that carbamazepine reactive metabolites bound specifically to P450 1A2 and 3A4. We confirmed the constitutive presence of P450 3A in human epidermis and after induction with coaltar of P450 1A. Consequently, the production in epidermis of carbamazepine reactive metabolites is theoretically possible with formation of P450 adduct metabolites.

Adult↗
PubMed1998

Nonhepatosplenic gammadelta T-cell lymphoma: a subset of cytotoxic lymphomas with mucosal or skin localization.

Human gammadelta T lymphocytes represent a minor subset of T cells in the peripheral blood, which exhibit a limited diversity and a tissue-restricted repertoire in contrast to their broad specificity. Most postthymic neoplasms that arise from this T-cell subpopulation belong to the hepatosplenic gammadelta lymphoma entity. Only a few cases of nonhepatosplenic gammadelta lymphomas have been described in detail previously. This study presents the clinicopathologic features of 11 consecutive cases of nonhepatosplenic gammadelta lymphoma. All were characterized by mucosal or skin initial involvement: nasal cavity (n = 3), gastrointestinal tract (n = 3), skin (n = 3), lung (n = 1), larynx (n = 1). Most patients presented with B symptoms (eight of 11), without peripheral lymphadenopathy and bone marrow involvement. A past history of chronic antigen exposure was noted in six cases, and four patients had features of immune deficiency. On histology, they were classified as pleomorphic tumors. Features of epitheliotropism and angiocentrism was observed in most cases. Tumor cells had a CD2+, CD3+, T-cell receptor (TCR)delta-1+), betaF1- phenotype. They were CD5- (9 of 10) and CD4-/CD8- (9 of 10) or CD8+ (1 of 10). A clonal gamma-chain gene rearrangement was detected in all tested cases (9/9). All cases had an activated cytotoxic T-cell intracellular antigen-1 (TIA-1)+, Granzyme B+ phenotype. Epstein-Barr virus (EBV) sequences were detected in six cases by in situ hybridization (ISH). Despite an aggressive clinical course, complete remission was obtained in three patients, and one of the latter required a peripheral blood stem-cell transplantation. Nonhepatosplenic gammadelta peripheral T-cell lymphoma can be regarded as a model of activated cytotoxic lymphoma, occurring in mucosae or skin. These appear to be derived from the subpopulation of tissue-restricted gammadelta lymphocytes, which are involved in the host epithelial surface surveillance. The role of chronic antigen exposure in the pathogenesis of these rare lymphomas can be suggested, in view of the past history observed in at least some patients.

Adult↗