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1.
Sci Rep ; 13(1): 3626, 2023 03 03.
Article in English | MEDLINE | ID: mdl-36869231

ABSTRACT

Circulating tumor cells (CTC) have been studied in various solid tumors but clinical utility of CTC in small cell lung cancer (SCLC) remains unclear. The aim of the CTC-CPC study was to develop an EpCAM-independent CTC isolation method allowing isolation of a broader range of living CTC from SCLC and decipher their genomic and biological characteristics. CTC-CPC is a monocentric prospective non-interventional study including treatment-naïve newly diagnosed SCLC. CD56+ CTC were isolated from whole blood samples, at diagnosis and relapse after first-line treatment and submitted to whole-exome-sequencing (WES). Phenotypic study confirms tumor lineage and tumorigenic properties of isolated cells for the 4 patients analyzed with WES. WES of CD56+ CTC and matched tumor biopsy reveal genomic alteration frequently impaired in SCLC. At diagnosis CD56+ CTC were characterized by a high mutation load, a distinct mutational profile and a unique genomic signature, compared to match tumors biopsies. In addition to classical pathways altered in SCLC, we found new biological processes specifically affected in CD56+ CTC at diagnosis. High numeration of CD56+ CTC (> 7/ml) at diagnosis was associated with ES-SCLC. Comparing CD56+ CTC isolated at diagnosis and relapse, we identify differentially altered oncogenic pathways (e.g. DLL3 or MAPK pathway). We report a versatile method of CD56+ CTC detection in SCLC. Numeration of CD56+ CTC at diagnosis is correlated with disease extension. Isolated CD56+ CTC are tumorigenic and show a distinct mutational profile. We report a minimal gene set as a unique signature of CD56+ CTC and identify new affected biological pathways enriched in EpCAM-independent isolated CTC in SCLC.


Subject(s)
Lung Neoplasms , Neoplastic Cells, Circulating , Small Cell Lung Carcinoma , Humans , Epithelial Cell Adhesion Molecule , Clinical Relevance , Prospective Studies , Genomics , Carcinogenesis , Membrane Proteins , Intracellular Signaling Peptides and Proteins
2.
Rev Mal Respir ; 35(7): 731-737, 2018 Sep.
Article in French | MEDLINE | ID: mdl-30115389

ABSTRACT

In cases of advanced EGFR mutation-positive non-small cell lung cancer, first or second generation EGFR-tyrosine kinase inhibitors (TKI-EGFR 1G or TKI-EGFR 2G) are recommended as first line treatment. Inexorably, progressive disease occurs and, in 50-60% of the cases, is secondary to a T790M resistant mutation. The prescription of osimertinib (TKI-EGFR3G) in second line is dependent on identification of the T790M mutation. We report 7 cases in which the identification of the T790M mutation required repeated analyses of cell free DNA and/or biopsies over a period of time. In some cases, a positive result was obtained a long time after progressive disease had been diagnosed during treatment with first or second generation EGFR-TKI. We discuss here the different modalities of screening for the T790M mutation and we encourage persevering in this search when no alternative mechanism of resistance has been identified.


Subject(s)
Carcinoma, Non-Small-Cell Lung/genetics , DNA Mutational Analysis , Drug Resistance, Neoplasm/genetics , Lung Neoplasms/genetics , Mutation, Missense , Aged , Amino Acid Substitution , Biopsy , Carcinoma, Non-Small-Cell Lung/drug therapy , ErbB Receptors/genetics , Female , Humans , Lung Neoplasms/drug therapy , Male , Methionine/genetics , Middle Aged , Protein Kinase Inhibitors/therapeutic use , Threonine/genetics , Time Factors
3.
Rev Mal Respir ; 34(9): 1016-1021, 2017 Nov.
Article in French | MEDLINE | ID: mdl-28918971

ABSTRACT

Nocardiosis is an infectious disease with wide range of clinical features, which can eventually lead to death. The agent responsible belongs to the genus Nocardia that includes about fifty different species. Nocardiosis occurs mainly in immunocompromised hosts. We report here three cases of disseminated nocardiosis misdiagnosed initially as cerebral metastatic lung cancer. These patients, including two immunocompetent hosts, presented with both pulmonary and cerebral lesions. In all three patients, the diagnosis was based on magnetic resonance imaging with diffusion sequence, apparent diffusion coefficient reconstruction and neurosurgical cerebral biopsies. Treatment with an appropriate antibiotic regimen was prolonged for several months. Progress was favorable with full resolution of the neurological symptoms and the radiological abnormalities. These three cases emphasize the diagnostic challenge of nocardiosis, especially in disseminated disease.


Subject(s)
Brain Abscess/complications , Brain Abscess/diagnosis , Lung Neoplasms/diagnosis , Nocardia Infections/complications , Nocardia Infections/diagnosis , Diagnosis, Differential , Female , Humans , Lung Neoplasms/pathology , Male , Middle Aged , Neoplasm Metastasis , Respiratory Tract Infections/complications , Respiratory Tract Infections/diagnosis
4.
Target Oncol ; 11(2): 167-74, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26315967

ABSTRACT

UNLABELLED: Retrospective studies suggested a benefit of first-line tyrosine kinase inhibitor (TKI) treatment continuation after response evaluation in solid tumors (RECIST) progression in epidermal growth factor receptor (EGFR)-mutated non-small-cell lung cancer (NSCLC) patients. The aim of this multicenter observational retrospective study was to assess the frequency of this practice and its impact on overall survival (OS). The analysis included advanced EGFR-mutated NSCLC patients treated with first-line TKI who experienced RECIST progression between June 2010 and July 2012. Among the 123 patients included (67 ± 12.7 years, women: 69 %, non smokers: 68 %, PS 0-1: 87 %), 40.6 % continued TKI therapy after RECIST progression. There was no difference between the patients who did and did not continue TKI therapy with respect to progression-free survival (PFS1: 10.5 versus 9.5 months, p = 0.4). Overall survival (OS) showed a non-significant trend in favor of continuing TKI therapy (33.0 vs. 21.2 months, p = 0.054). Progressions were significantly less symptomatic in the TKI continuation group than in the discontinuation group (18 % vs. 37 %, p < 0.01). Univariate analysis showed a higher risk of death among patients with PS >1 (HR 4.33, 95 %CI: 2.21-8.47, p = 0.001), >1 one metastatic site (HR 1.96, 95 %CI: 1.06-3.61, p = 0.02), brain metastasis (HR 1.75, 95 %CI: 1.08-2.84, p = 0.02) at diagnosis, and a trend towards a higher risk of death in cases of TKI discontinuation after progression (HR 1.62, 95 %CI: 0.98-2.67, p = 0.056 ). In multivariate analysis only PS >1 (HR 6.27, 95 %CI: 2.97-13.25, p = 0.00001) and >1 metastatic site (HR 2.54, 95 %CI: 1.24-5.21, p = 0.02) at diagnosis remained significant. This study suggests that under certain circumstances, first-line TKI treatment continuation after RECIST progression is an acceptable option in EGFR-mutated NSCLC patients. CLINICAL TRIAL INFORMATION: NCT02293733.


Subject(s)
Carcinoma, Non-Small-Cell Lung/drug therapy , ErbB Receptors/antagonists & inhibitors , Lung Neoplasms/drug therapy , Protein Kinase Inhibitors/therapeutic use , Aged , Biopsy , Carcinoma, Non-Small-Cell Lung/pathology , Disease Progression , Disease-Free Survival , ErbB Receptors/genetics , Female , Humans , Kaplan-Meier Estimate , Lung Neoplasms/pathology , Male , Mutation , Retrospective Studies
5.
Prog Urol ; 24(16): 1069-75, 2014 Dec.
Article in French | MEDLINE | ID: mdl-25242339

ABSTRACT

INTRODUCTION: Laparoscopy has become the gold-standard approach for excision of benign adrenal tumors but the question of its safety for malignant lesions is still controversial. Our aim was to evaluate the oncologic outcome of laparoscopic adrenalectomy for adrenal metastasis and to look for predictors of a negative surgical outcome. PATIENTS AND METHODS: We retrospectively reviewed the charts of all patients who underwent laparoscopic adrenalectomy for suspicion of adrenal metastasis between 2007 and 2013 at a single academic institution. Recurrence-free survival (RFS) and cancer-specific survival (CSS) were estimated using the Kaplan-Meier method. Univariate analysis was performed to determine risk factors of negative surgical outcome (positive surgical margins, complications, conversion, significant blood loss) and predictors of RFS and CSS. RESULTS: Thirteen patients underwent 14 laparoscopic adrenalectomies. All patients were operated by a single highly experienced surgeon. Complications occurred in 2 patients (15%): 2 blood transfusions (Clavien-score=2). There were 3 positive surgical margins (21%). Mean length of hospital stay was 4.3 days. Unadjusted RFS and CSS were respectively 48.4% and 83.3% at 1 year, 39.5% and 66.7% at 5 years. In univariate analysis, tumor size was the only risk factor of complication (P=.009) and conversion (P=0.009). Capsule invasion and tumor size were risk factors of positive surgical margins (P=0.01 and P<0.0001). One hundred percent of complications, conversion and positive surgical margins occurred in tumor>7.5 cm on preoperative CT-scan. No predictors of RFS and CSS was found in univariate analysis. CONCLUSION: Laparoscopic adrenalectomy for adrenal metastasis achieves good surgical and oncologic outcomes. When performed by highly experienced surgeon, complications and positive surgical margins occur only in tumors>7.5 cm. These patients may benefit from an open surgical approach.


Subject(s)
Adrenal Gland Neoplasms/secondary , Adrenal Gland Neoplasms/surgery , Adrenalectomy/methods , Laparoscopy/adverse effects , Adrenal Gland Neoplasms/diagnostic imaging , Adrenal Gland Neoplasms/mortality , Adrenalectomy/adverse effects , Aged , Blood Loss, Surgical , Blood Transfusion/statistics & numerical data , Conversion to Open Surgery , Disease-Free Survival , Female , Humans , Kaplan-Meier Estimate , Male , Medical Records , Middle Aged , Neoplasm Invasiveness , Radionuclide Imaging , Retrospective Studies , Risk Factors , Treatment Outcome
6.
Rev Mal Respir ; 31(7): 591-600, 2014 Sep.
Article in French | MEDLINE | ID: mdl-25239580

ABSTRACT

BACKGROUND: Thymic epithelial tumors (TET), including thymomas and thymic carcinomas, are rare and characterized by very different evolutionary patterns depending on histology and invasion stage. The therapeutic management is not well defined but is a subject of increasing interest. The descriptive and analytic objectives of this retrospective monocentric study were to analyze the clinical characteristics of patients with TET, and to assess the management of these tumors in our centre. METHODS: Adult patients with TET managed in the Rennes university hospital in the period 2000-2011 were selected via the pathology department. Their clinical and pathological features and survival were analyzed retrospectively. RESULTS: Fifty TET were retrieved (46 thymomas and 4 thymic carcinomas). Their clinical and histological features and their invasion stages were concordant with published studies. Their diagnostic and therapeutic managements were also in accordance with current guidelines. In univariate analysis, myasthenia and surgery were associated with better survival rates. CONCLUSION: Management of TET in Rennes university hospital is in accordance with guidelines.


Subject(s)
Neoplasms, Glandular and Epithelial/diagnosis , Neoplasms, Glandular and Epithelial/therapy , Thymus Neoplasms/diagnosis , Thymus Neoplasms/therapy , Adolescent , Adult , Aged , Aged, 80 and over , Female , France , Hospitals, University , Humans , Male , Middle Aged , Retrospective Studies , Young Adult
7.
Lung Cancer ; 85(3): 415-9, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25082565

ABSTRACT

BACKGROUND: Concomitant administration of erlotinib with standard chemotherapy does not appear to improve survival among patients with non-small-cell lung cancer (NSCLC), but preliminary studies suggest that sequential administration might be effective. OBJECTIVE: To assess the efficacy and tolerability of second-line sequential administration of erlotinib and docetaxel in advanced NSCLC. METHODS: In an open-label phase II trial, patients with advanced NSCLC, EGFR wild-type or unknown, PS 0-2, in whom initial cisplatin-based chemotherapy had failed were randomized to sequential erlotinib 150 mg/d (day 2-16)+docetaxel (75 mg/m(2) d1) (arm ED) or docetaxel (75 mg/m(2) d1) alone (arm D) (21-day cycle). The primary endpoint was the progression-free survival rate at 15 weeks (PFS 15). Secondary endpoints included PFS, overall survival (OS), the overall response rate (ORR) and tolerability. Based on a Simon optimal two-stage design, the ED strategy was rejected if the primary endpoint was below 33/66 patients at the end of the two Simon stages. RESULTS: 147 patients were randomized (median age: 60±8 years, PS 0/1/2: 44/83/20 patients; males: 78%). The ED strategy was rejected, with only 18 of 73 patients achieving PFS15 in arm ED at the end of stage 2 and 17 of 74 patients in arm D. In arms ED and D, respectively, median PFS was 2.2 and 2.5 months and median OS was 6.5 and 8.3 months. CONCLUSION: Sequential erlotinib and docetaxel was not more effective than docetaxel alone as second-line treatment for advanced NSCLC with wild-type or unknown EGFR status.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/drug therapy , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Carcinoma, Non-Small-Cell Lung/mortality , Carcinoma, Non-Small-Cell Lung/pathology , Docetaxel , Erlotinib Hydrochloride , Female , Humans , Lung Neoplasms/mortality , Lung Neoplasms/pathology , Male , Middle Aged , Quinazolines/administration & dosage , Retreatment , Risk Factors , Taxoids/administration & dosage , Treatment Failure , Treatment Outcome
8.
Rev Mal Respir ; 30(2): 125-36, 2013 Feb.
Article in French | MEDLINE | ID: mdl-23419443

ABSTRACT

The incidence of lung cancer during pregnancy is very low, but it is becoming more frequent in industrialized countries both because of the increase in smoking in young women and because women are becoming pregnant later in life. Usually, the cancer has a poor prognosis due to the presence of metastatic disease at the time of diagnosis. Diagnosis and management are delicate, and should deal with the gestational age, the maternal prognosis, the fetal toxicity of treatments, but also with the worsening of maternal prognosis and the risk of neoplastic cells being transmitted to the fetus in case of delayed treatment. Psychological and ethical considerations complicate the decision process. We present a review of the epidemiology, clinical characteristics, management, and prognosis concerning lung cancer during pregnancy. Finally, it is important to remember that young women with lung cancer should be advised to use a reliable form of contraception.


Subject(s)
Lung Neoplasms/diagnosis , Lung Neoplasms/therapy , Pregnancy Complications, Neoplastic/diagnosis , Pregnancy Complications, Neoplastic/therapy , Abnormalities, Drug-Induced/prevention & control , Abnormalities, Radiation-Induced/prevention & control , Abortion, Therapeutic , Adult , Antineoplastic Agents/adverse effects , Antineoplastic Agents/therapeutic use , Breast Feeding , Contraception , Contraindications , Diagnostic Imaging/adverse effects , Diagnostic Imaging/methods , Disease Management , Female , Fetus/drug effects , Fetus/radiation effects , Humans , Incidence , Infant, Newborn , Lung Neoplasms/epidemiology , Maternal Age , Maternal-Fetal Exchange , Neoplasms/congenital , Neoplastic Cells, Circulating , Pregnancy , Pregnancy Complications, Neoplastic/epidemiology , Pregnancy Outcome , Prognosis , Radiotherapy/adverse effects , Risk Factors , Smoking/adverse effects , Smoking/epidemiology
9.
Lung Cancer ; 77(1): 97-103, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22405570

ABSTRACT

BACKGROUND: The aim of this randomized phase II trial was to evaluate the feasibility and activity of weekly gemcitabine (G) followed by erlotinib at disease progression (arm A) versus erlotinib followed by G at progression (arm B) in vulnerable elderly patients with advanced non small-cell lung cancer (NSCLC), selected on the basis of a comprehensive geriatric assessment (CGA). METHODS: Vulnerable elderly chemotherapy-naive patients with stage IIIB/IV NSCLC were selected after a CGA (socioeconomic, cognitive and emotional status, depression, nutritional status, ADL and IADL assessments). The primary endpoint was the time to second progression (TTP2). Overall survival (OS), time to first progression (TTP1) and safety were secondary endpoints. RESULTS: Between May 2006 and January 2010, 21 centers enrolled 100 patients, of whom 94 were eligible. TTP2 was 4.3 and 3.5 months in arm A and arm B, respectively; TTP1 was 2.5 and 2.2 months; and the median OS time was 4.4 and 3.9 months. The respective one-year survival rates were 27.3% and 20%. There was no major unexpected toxicity. CONCLUSION: In vulnerable elderly patients with NSCLC not selected for EGFR expression, both strategies were feasible but had modest efficacy. Further studies are needed to identify elderly patients who should receive palliative care only.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Geriatric Assessment , Lung Neoplasms/drug therapy , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Carcinoma, Non-Small-Cell Lung/mortality , Carcinoma, Non-Small-Cell Lung/pathology , Deoxycytidine/administration & dosage , Deoxycytidine/analogs & derivatives , Disease Progression , Disease-Free Survival , Erlotinib Hydrochloride , Female , Humans , Kaplan-Meier Estimate , Lung Neoplasms/mortality , Lung Neoplasms/pathology , Male , Neoplasm Staging , Quinazolines/administration & dosage , Treatment Outcome , Gemcitabine
10.
Br J Cancer ; 105(8): 1123-30, 2011 Oct 11.
Article in English | MEDLINE | ID: mdl-21934690

ABSTRACT

BACKGROUND: Elderly cancer patients form a heterogeneous population in which therapeutic decision-making is often difficult. The aim of this randomised phase II trial was to evaluate the feasibility and activity of weekly docetaxel/gemcitabine (DG) followed by erlotinib after progression (arm A) vs erlotinib followed by DG after progression (arm B) in fit elderly patients with advanced non small-cell lung cancer (NSCLC). METHODS: Elderly chemotherapy-naive patients with stage IIIB/IV NSCLC were selected after a comprehensive geriatric assessment (socioeconomic, cognitive, depression, ADL and IADL assessments). The primary endpoint was the time to second progression (TTP2). Overall survival (OS), the time to first progression (TTP1) and safety were secondary endpoints. RESULTS: Between July 2006 and November 2008, 22 centres enrolled 100 patients. TTP2 was 7.5 and 5.8 months in arm A and arm B, respectively; TTP1 was 4.7 and 2.7 months; and the median OS time was 9.4 and 7.1 months; the respective 1-year survival rates were 36.2 and 31.4%. There was no major unexpected toxicity. CONCLUSION: These results suggest that weekly DG, followed by erlotinib, is a promising treatment for fit elderly patients with NSCLC; the efficacy of the reverse sequence was insufficient to recommend it for EGFR-non-selected patients.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/drug therapy , Aged , Aged, 80 and over , Carcinoma, Non-Small-Cell Lung/pathology , Deoxycytidine/administration & dosage , Deoxycytidine/analogs & derivatives , Disease Progression , Docetaxel , Drug Administration Schedule , Erlotinib Hydrochloride , Geriatric Assessment , Humans , Lung Neoplasms/pathology , Quinazolines/administration & dosage , Taxoids/administration & dosage , Gemcitabine
11.
Rev Mal Respir ; 27(6): 639-43, 2010 Jun.
Article in French | MEDLINE | ID: mdl-20610078

ABSTRACT

Ras genes encode a family of membrane proteins involved in the regulation of cell growth. Mutations of Ras stimulate cell growth and thus can play a role in carcinogenesis. The search for mutations of Ras is possible by PCR on bronchial biopsies or surgical specimens. They are found in 15 to 20% of non-small cell lung cancers. In the disease's early stage, the presence of a Ras mutation can be a negative predictor of the effectiveness of adjuvant chemotherapy. In the advanced stage of the disease, it is a factor predicting a poor prognosis. Although prospective studies have found no statistically significant negative influence of the presence of a mutation of Ras on the effectiveness of tyrosine kinase inhibitors of EGFR, it is likely that these treatments will be of limited value in this population given the lack of response observed when Ras is mutated. Prospective and functional studies are needed to determine the value of the different mutations observed.


Subject(s)
Genes, ras/genetics , Lung Neoplasms/genetics , Humans , Lung Neoplasms/drug therapy , Mutation , Prognosis
12.
Rev Pneumol Clin ; 64(2): 50-61, 2008 Apr.
Article in French | MEDLINE | ID: mdl-18589284

ABSTRACT

The occurrence of pain during the course of bronchial carcinoma is nearly inescapable and often constitutes the main symptom for patients and those close to them. While pain control is held to be a priority of care in cancerology in the future, this goal is not always reached due to insufficient implementation of recommendations, however widely accessible. Our aim is to present the different aspects of pain treatment through the details of both pharmacological and nonpharmacological means.


Subject(s)
Analgesics/therapeutic use , Carcinoma, Bronchogenic/physiopathology , Lung Neoplasms/physiopathology , Pain/drug therapy , Palliative Care/methods , Analgesics, Opioid/adverse effects , Analgesics, Opioid/therapeutic use , Combined Modality Therapy , Humans
13.
Ann Oncol ; 17(9): 1412-7, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16790516

ABSTRACT

BACKGROUND: Brain metastases (BM) considerably worsen the prognosis of non-small-cell lung cancer (NSCLC) patients. The usefulness and choice of chemotherapy remain uncertain in this indication since these patients are excluded from most clinical trials. We conducted a phase II study to determine the efficacy and tolerability of up-front chemotherapy with association of temozolomide and cisplatin in NSCLC patients with BM. PATIENTS AND METHODS: Fifty NSCLC patients with BM received temozolomide (200 mg/m(2)/day for 5 days every 28 days) and cisplatin (75 mg/m(2) at day 1 of each cycle), up to six cycles, followed by whole brain radiotherapy (WBRT). An evaluation was carried out every two cycles and after WBRT. WBRT was performed earlier in case of progressive disease at any time or stable disease after cycle 4. RESULTS: Eight objective responses were achieved (16%). Overall median survival was 5 months. Median time to progression was 2.3 months. Ten patients (20%) presented a grade 3/4 neutropenia and 11 patients (22%) presented a grade 3/4 thrombopenia. CONCLUSION: This study demonstrates a lack of efficacy of up-front chemotherapy with association of temozolomide and cisplatin in these patients. Nevertheless, it supports the feasibility of chemotherapy before brain radiotherapy in NSCLC patients with BM.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Brain Neoplasms/radiotherapy , Brain Neoplasms/secondary , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/radiotherapy , Lung Neoplasms/drug therapy , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Cisplatin/administration & dosage , Cisplatin/adverse effects , Dacarbazine/administration & dosage , Dacarbazine/adverse effects , Dacarbazine/analogs & derivatives , Female , Humans , Lung Neoplasms/pathology , Male , Middle Aged , Temozolomide , Treatment Outcome
15.
Autoimmunity ; 33(3): 213-24, 2001 May.
Article in English | MEDLINE | ID: mdl-11683380

ABSTRACT

B cell receptor (BcR) signaling requires a tight regulation of several protein tyrosine kinases and phosphatases, and associated co-receptors. Mounting evidence indicates that abnormal BcR signaling, such as occurs in SHP-1 and Lyn-deficient mice, results in production of pathogenic autoantibodies and lupus-like glomerulonephritis, suggesting that altered signaling thresholds could underlie the development of systemic autoimmunity. To test this hypothesis, we investigated expression of BcR-associated signaling molecules in lymphocytes from patients with systemic lupus erythematosus (SLE) during inactive phases of the disease. We found that the transmembrane regulatory protein tyrosine phosphatase CD45 is expressed at abnormal levels. Strikingly, this reduction persisted during four months of follow-up. By contrast, despite its potent role as a regulator of thymus-independent immune responses and of B cell life span, the CD22 co-receptor is expressed at normal levels in B lymphocytes isolated ex vivo from SLE patients. We also noted unusual levels of the cytosolic protein tyrosine kinase Lyn and the protein tyrosine phosphatase SHP-1 in the lymphocytes of the patients. Since in normal B cells Lyn and SHP-1 act in concert within a common negative pathway in which CD45 counteracts SHP-I regulatory role, we propose that this feedback regulatory pathway is crippled to different degrees in human SLE B cells. Break of the balance between positive and negative signaling molecules likely modifies the BcR signaling thresholds. Such alterations, together with other factors, may contribute to the disruption of self-tolerance in this disease.


Subject(s)
Cell Adhesion Molecules , Lectins , Lupus Erythematosus, Systemic/immunology , Receptors, Antigen, B-Cell/metabolism , Animals , Antigens, CD/metabolism , Antigens, Differentiation, B-Lymphocyte/metabolism , B-Lymphocytes/enzymology , B-Lymphocytes/immunology , Humans , Intracellular Signaling Peptides and Proteins , Leukocyte Common Antigens/metabolism , Lupus Erythematosus, Systemic/enzymology , Lymphocyte Activation , Mice , Protein Tyrosine Phosphatase, Non-Receptor Type 11 , Protein Tyrosine Phosphatase, Non-Receptor Type 6 , Protein Tyrosine Phosphatases/metabolism , Self Tolerance , Sialic Acid Binding Ig-like Lectin 2 , Signal Transduction , src-Family Kinases/metabolism
16.
Lupus ; 9(8): 622-31, 2000.
Article in English | MEDLINE | ID: mdl-11035438

ABSTRACT

The objectives were to provide estimates of the prevalence of autoantibody (Ab) directed to CD45 in lupus patients, identify the target autoantigen(s), and determine the ability of such reactivity to mediate neutralization of T lymphocytes. Sera from 64 patients were studied using 2 assays: Western blot and an ELISA with CD45 eluted from 3 cell lines as antigen (U937, Jurkat and Daudi). The role of carbohydrate specificity was investigated using enzyme digestion of blotted glycans, competition with sugars, and inhibition with lectins. Apoptosis was studied through annexin V binding, and cell cycle analysis using the propidium iodide method. AutoAb to CD45 were detected in 16/64 sera (25%) by Western blot, and 21/32 sera (66%) found positive in the ELISA. CD45 purified from Daudi cells was identified in the ELISA, but not in the blot. AutoAb were of the IgM and the IgG isotypes, but not specific for a particular cell type or CD45 isoform: 2 dominant specificities were recognized, one against p180, and another against high MW isoforms. Neuraminidase-induced enhancement of reactivity, together with the inhibitory effect of N-acetyl galactosamine and Dolichos diflorus lectin suggest that the epitopes are carbohydrates. AutoAb which were specific for activated CD4+T cells triggered the annexin V binding, and, in 2 of 4 cases, lymphocytes underwent apoptosis. In conclusion, carbohydrate conformational epitopes may be important as target antigens, and some CD45 autoAb have the capacity to neutralize activated T cells through anergy or apoptosis.


Subject(s)
Autoantibodies/blood , Autoantibodies/immunology , Leukocyte Common Antigens/immunology , Lupus Erythematosus, Systemic/immunology , Lymphocyte Activation , T-Lymphocytes/immunology , Antibodies, Monoclonal , Binding Sites, Antibody , Burkitt Lymphoma , Enzyme-Linked Immunosorbent Assay , Humans , Jurkat Cells , Lupus Erythematosus, Systemic/blood , Reference Values , Tumor Cells, Cultured , U937 Cells
17.
Histol Histopathol ; 15(2): 587-91, 2000 04.
Article in English | MEDLINE | ID: mdl-10809380

ABSTRACT

CD45RO+ T cells are referred to as memory or helper-inducer while CD45RA+ T cells are regarded as naive or suppressor-inducer T cells. The former population predominates in the peripheral blood and even more in the synovial fluid of patients with rheumatoid arthritis, to the expense of the latter population. Within the CD45RB+ compartment, there appears to be more of the fully-differentiated than of the early-differentiated CD4+ T cells. In spite of the fact that these lymphocytes are close to undergoing apoptosis, this programmed cell death is inhibited in the rheumatoid synovium.


Subject(s)
Arthritis, Rheumatoid/immunology , Leukocyte Common Antigens/immunology , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Humans , Immunophenotyping , Leukocyte Common Antigens/metabolism , Protein Isoforms/immunology , Protein Isoforms/metabolism , T-Lymphocytes/immunology , Tissue Distribution , fas Receptor/immunology
19.
Eur J Immunol ; 28(12): 4170-6, 1998 12.
Article in English | MEDLINE | ID: mdl-9862353

ABSTRACT

The CD5 molecule is expressed by a B cell subset. We have demonstrated that resting B cells do not proliferate in response to CD5 ligation, whereas cells preactivated with anti-IgM and IL-2 do so. Here, we specifically studied the effects of anti-CD5 and anti-IgM on apoptosis of CD5+ B cells. Both ligation of CD5 or of surface IgM (sIgM) resulted in apoptosis. This started earlier following ligation of CD5 than with sIgM, and both responses were time dependent. CD5-induced apoptosis was independent of the epitope recognized or the way the antibody was presented to the B cells. CD5+ B cells were more sensitive to IgM-induced apoptosis than CD5 B cells. Engagement of CD5 or CD3 expressed by T cells failed to induce apoptosis. Our data indicate differences in the function of CD5 molecules on tonsillar B cells, compared with blood T cells and suggest that cross-linking CD5 on B cell activates specific pathways responsible for apoptosis.


Subject(s)
Apoptosis/immunology , B-Lymphocytes/immunology , CD5 Antigens/immunology , T-Lymphocytes/immunology , B-Lymphocytes/pathology , Cells, Cultured , Humans , Ligands , T-Lymphocytes/pathology
20.
J Autoimmun ; 11(5): 485-8, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9802933

ABSTRACT

Western blotting with U937 cell extracts as the substrate, and enzyme-linked immunosorbent assays (ELISA) with U937-, Jurkat- and Daudi cell-purified CD45 molecules were used to detect anti-CD45 reactivity in patients with systemic lupus erythematosus (SLE). By immunoblotting, 16 of 64 SLE sera were shown to be positive (25.0%). In the ELISAs, 13 out of 18 SLE sera reacted with the target CD45. Of these, three were not detectable on the blot. Importantly, 12 of these ELISA-positive sera contained IgM and IgG auto-antibodies. Neuraminidase-treatment of U937-precipitated CD45 molecules enhanced the reactivity to most of the isoforms, indicating that the antibodies may bind to asialylated polysaccharides.


Subject(s)
Autoantibodies/blood , Leukocyte Common Antigens/immunology , Lupus Erythematosus, Systemic/immunology , Adult , Aged , Antibody Specificity , Case-Control Studies , Cell Line , Female , Humans , Immunoglobulin Isotypes/blood , Jurkat Cells , Leukocyte Common Antigens/isolation & purification , Male , Middle Aged , U937 Cells
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