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1.
Leuk Lymphoma ; 63(4): 821-833, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34865586

RESUMO

Intratumoral injection of G100, a toll-like receptor 4 (TLR4) agonist, was shown pre-clinically to stimulate anti-tumor immune responses and tumor regression. This open-label, multicenter, phase 1/2 trial evaluated the safety, tolerability, and preliminary efficacy of intratumoral G100 injections following localized low-dose radiation in patients with follicular lymphoma (ClinicalTrials.gov #NCT02501473). The study was comprised of a G100 dose escalation (5 or 10 µg/dose, or 20 µg/dose for large tumors); a randomized component comparing G100 to G100 plus pembrolizumab; and G100 20 µg/dose expansion. Adverse events grade ≥3 were uncommon in patients treated with G100, and no unexpected toxicities were observed when combined with pembrolizumab. G100 20 µg (n = 18) resulted in an overall response rate of 33.3% and abscopal tumor regression in 72.2% of patients. This early-phase study provides a foundation for combining an intratumoral TLR4 agonist with agents to produce immune-mediated responses in follicular lymphoma with limited added toxicity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Linfoma Folicular , Receptor 4 Toll-Like , Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Humanos , Linfoma Folicular/tratamento farmacológico , Receptor 4 Toll-Like/agonistas
2.
J Clin Oncol ; 40(12): 1291-1300, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-34260265

RESUMO

PURPOSE: CMB305 is a heterologous prime-boost vaccination regimen created to prime NY-ESO-1-specific CD8 T-cell populations and then activate the immune response with a potent TLR-4 agonist. This open-label randomized phase II trial was designed to investigate the efficacy and safety of adding the CMB305 regimen to atezolizumab (anti-programmed death ligand-1 therapy) in comparison with atezolizumab alone in patients with synovial sarcoma or myxoid liposarcoma. PATIENTS AND METHODS: Patients with locally advanced, relapsed, or metastatic synovial sarcoma or myxoid liposarcoma (any grade) were randomly assigned to receive CMB305 with atezolizumab (experimental arm) or atezolizumab alone (control arm). The primary end points were progression-free survival (PFS) and overall survival (OS) analyzed using the Kaplan-Meier method. Safety and immune responses were assessed. RESULTS: A total of 89 patients were enrolled; 55.1% had received ≥ 2 prior lines of chemotherapy. Median PFS was 2.6 months and 1.6 months in the combination and control arms, respectively (hazard ratio, 0.9; 95% CI, 0.6 to 1.3). Median OS was 18 months in both treatment arms. Patients treated with combination therapy had a significantly higher rate of treatment-induced NY-ESO-1-specific T cells (P = .01) and NY-ESO-1-specific antibody responses (P < .0001). In a post hoc analysis of all dosed patients, OS was longer (36 months) in the subset who developed anti-NY-ESO-1 T-cell immune response (hazard ratio, 0.3; P = .02). CONCLUSION: Although the combination of CMB305 and atezolizumab did not result in significant increases in PFS or OS compared with atezolizumab alone, some patients demonstrated evidence of an anti-NY-ESO-1 immune response and appeared to fare better by imaging than those without such an immune response. Combining prime-boost vaccines such as CMB305 with anti-programmed death ligand-1 therapies merits further evaluation in other clinical contexts.


Assuntos
Lipossarcoma Mixoide , Sarcoma Sinovial , Sarcoma , Neoplasias de Tecidos Moles , Adjuvantes Imunológicos , Adulto , Anticorpos Monoclonais Humanizados , Antígenos de Neoplasias , Humanos , Sarcoma/tratamento farmacológico
3.
Cancer Med ; 9(13): 4593-4602, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32374488

RESUMO

BACKGROUND: Outcomes data regarding advanced synovial sarcoma (SS) and myxoid/round cell liposarcoma (MRCL) are limited, consisting primarily of retrospective series and post hoc analyses of clinical trials. METHODS: In this multi-center retrospective study, data were abstracted from the medical records of 350 patients from nine sarcoma centers throughout the United States and combined into a registry. Patients with advanced/unresectable or metastatic SS (n = 249) or MRCL (n = 101) who received first-line systemic anticancer therapy and had records of tumor imaging were included. Overall survival (OS), time to next treatment, time to distant metastasis, and progression-free survival (PFS) were evaluated using the Kaplan-Meier method and Cox regression. RESULTS: At start of first-line systemic anticancer therapy, 92.4% of patients with SS and 91.1% of patients with MRCL had metastatic lesions. However, 74.7% of patients with SS and 72.3% of patients with MRCL had ≥2 lines of systemic therapy. Median OS and median PFS from first-line therapy for SS was 24.7 months (95% CI, 20.9-29.4) and 7.5 months, respectively (95% CI, 6.4-8.4). Median OS and median PFS from start of first-line therapy for MRCL was 29.9 months (95% CI, 27-44.6) and 8.9 months (95% CI 4.5-12.0). CONCLUSIONS: To the best of our knowledge, this is the largest retrospective study of patients with SS and MRCL. It provides an analysis of real-world clinical outcomes among patients treated at major sarcoma cancer centers and could inform treatment decisions and design of clinical trials. In general, the survival outcomes for this selected population appear more favorable than in published literature.


Assuntos
Antineoplásicos/uso terapêutico , Institutos de Câncer , Lipossarcoma Mixoide/tratamento farmacológico , Sarcoma Sinovial/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Estimativa de Kaplan-Meier , Lipossarcoma Mixoide/mortalidade , Lipossarcoma Mixoide/patologia , Lipossarcoma Mixoide/secundário , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Análise de Regressão , Estudos Retrospectivos , Sarcoma Sinovial/mortalidade , Sarcoma Sinovial/patologia , Sarcoma Sinovial/secundário , Resultado do Tratamento , Estados Unidos , Adulto Jovem
4.
JCO Precis Oncol ; 2: 1-13, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35135111

RESUMO

PURPOSE: Liquid biopsies represent an attractive alternative to tissue biopsies, particularly rebiopsies, in determining patient eligibility for targeted therapies. Clinical utility of urine genotyping, however, has not been explored extensively. We evaluated epidermal growth factor receptor (EGFR) T790M detection in matched urine, plasma, and tissue and the clinical outcomes of patients with advanced non-small-cell lung cancer treated with rociletinib. METHODS: Tissue (n = 540), plasma (n = 482), and urine (n = 213) were collected from evaluable patients enrolled in TIGER-X, a phase I/II study. Genotyping was performed by therascreen EGFR testing in tissue, BEAMing in plasma, and a quantitative short footprint assay (Trovera) in urine, which was used to further examine discordant samples. RESULTS: Positive percent agreement with tissue T790M results was similar for urine (82%; 142 of 173) and plasma (81%; 313 of 387) genotyping. Urine and plasma together identified more patients who were T790M positive (92%) than tissue alone (83%) among matched samples (n = 177). The ability to identify mutations in plasma was strongly associated with M stage (P < .001); rate of T790M detection for patients with M1a/M0 disease increased from 54% for plasma alone to 85% when urine and plasma were both examined. Objective response rates of patients who were T790M positive were comparable between tumor (34%), plasma (32%), and urine (37%). CONCLUSION: Clinical response to rociletinib was comparable irrespective of whether T790M status was identified by liquid or tissue biopsy. Combined, urine and plasma identified a higher percentage of patients who were T790M positive than tumor genotyping alone and improved detection of T790M, particularly in the absence of distant metastases. These findings support the noninvasive analysis of urine and plasma before tumor rebiopsy when assessing T790M status.

5.
Lung Cancer ; 93: 95-103, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26898621

RESUMO

OBJECTIVES: REVEL demonstrated that ramucirumab+docetaxel (RAM+DTX) improved overall survival, progression-free survival, and objective response rate in patients with advanced/metastatic non-small cell lung cancer with progression after platinum-based chemotherapy. This analysis examined quality of life (QoL) as assessed by the Lung Cancer Symptom Scale (LCSS) and clinician-reported functional status. MATERIALS AND METHODS: The LCSS includes 6 symptom and 3 global items measured on a 0-100-mm scale; higher scores represent greater symptom burden. LCSS and ECOG PS data were collected at baseline, every 3-week cycle, the summary visit, and at the 30-day follow-up. LCSS total score and Average Symptom Burden Index (ASBI) were calculated. The primary analysis compared time to deterioration (TtD) between treatment arms for all individual items and summary scores, defined as increase from baseline by ≥ 15 mm using the Kaplan-Meier method and Cox regression. TtD to ECOG PS ≥ 2 was analyzed. RESULTS: There were 1253 patients randomized to receive RAM+DTX or placebo+docetaxel (PL+DTX). Across all assessments, LCSS compliance was approximately 75% and balanced across arms. The mean (SD) baseline LCSS total score was 27.3mm (17.08 mm) on RAM+DTX and 29.6mm (17.59 mm) on PL+DTX. At 30-day follow-up, mean (SD) LCSS total score was 32.0 (19.03) on RAM+DTX and 32.5 (19.87) on PL+DTX. The TtD for all LCSS scores was similar between treatment arms. Stratified HRs (95% CI) for LCSS total score and ASBI were HR=0.99 (0.81, 1.22), p=0.932 and HR=0.93 (0.75, 1.15), p=0.514 with approximately 70% of patients censored. TtD to PS ≥ 2 was similar between treatment arms (HR=1.03 [95% CI: 0.85, 1.26], p=0.743) with approximately two-thirds of the patients censored. CONCLUSION: In addition to improvement of clinical efficacy outcomes demonstrated in REVEL, these results suggest that adding ramucirumab to docetaxel did not impair patient QoL, symptoms, or functioning.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Qualidade de Vida , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Docetaxel , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Masculino , Metástase Neoplásica , Estadiamento de Neoplasias , Platina/administração & dosagem , Platina/uso terapêutico , Modelos de Riscos Proporcionais , Retratamento , Taxoides/administração & dosagem , Resultado do Tratamento , Ramucirumab
6.
Cancer ; 121(6): 883-92, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25377507

RESUMO

BACKGROUND: Vascular endothelial growth factor (VEGF)-mediated angiogenesis plays an important role in non-small cell lung cancer (NSCLC). Ramucirumab is a human immunoglobulin G1 monoclonal antibody that inhibits VEGF receptor 2. This phase 2 study investigated ramucirumab in combination with first-line pemetrexed and platinum chemotherapy in advanced/metastatic NSCLC. METHODS: Eligible stage IV nonsquamous NSCLC patients with no prior chemotherapy for metastatic disease were randomized 1:1 to pemetrexed and carboplatin (or cisplatin) or ramucirumab (10 mg/kg) plus pemetrexed and carboplatin (or cisplatin) once every 3 weeks. Treatment was given for 4 to 6 cycles, and this was followed by a maintenance phase with pemetrexed or ramucirumab and pemetrexed. The primary endpoint was progression-free survival (PFS) with a sample size of sufficient power to detect an increase from 7 to 10.4 months. RESULTS: From October 2010 to October 2011, 140 patients were randomized (pemetrexed-platinum arm, 71; ramucirumab-pemetrexed-platinum arm, 69), and most baseline characteristics were similar for the 2 treatment arms. The median PFS was 5.6 months for the pemetrexed-platinum arm and 7.2 months for the ramucirumab-pemetrexed-platinum arm (hazard ratio, 0.75; P = .132). The objective response rates were 38.0% and 49.3% for the pemetrexed-platinum and ramucirumab-pemetrexed-platinum arms, respectively (P = .180). The disease control rate was 70.4% for the pemetrexed-platinum arm and 85.5% for the ramucirumab-pemetrexed-platinum arm (P = .032). The grade 3 or higher adverse events occurring in 10% or more of patients were thrombocytopenia, neutropenia, fatigue, anemia, nausea, back pain, and hypertension. CONCLUSIONS: The primary endpoint of significant prolongation of PFS was not met; however, ramucirumab showed evidence of clinical activity in combination with pemetrexed and platinum in nonsquamous NSCLC patients. The addition of ramucirumab to pemetrexed and platinum did not result in new or unexpected safety findings.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Adolescente , Adulto , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Intervalo Livre de Doença , Feminino , Glutamatos/administração & dosagem , Glutamatos/efeitos adversos , Guanina/administração & dosagem , Guanina/efeitos adversos , Guanina/análogos & derivados , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Pemetrexede , Adulto Jovem , Ramucirumab
7.
J Thorac Oncol ; 9(10): 1532-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25170639

RESUMO

INTRODUCTION: The objective of this study was to determine whether the addition of ramucirumab to first-line paclitaxel-carboplatin chemotherapy in patients with advanced non-small-cell lung cancer (NSCLC) resulted in a 6-month progression-free survival (PFS) rate that compares favorably with the historic rate for bevacizumab combined with paclitaxel-carboplatin in this patient population. METHODS: In this phase II, single-arm, open-label, multicenter study, 40 patients with advanced NSCLC received ramucirumab (10 mg/kg intravenous [IV]) followed by paclitaxel (200 mg/m IV) and carboplatin area under the curve = 6 on day 1 every 21 days as first-line therapy. Therapy continued for up to six cycles. Patients not experiencing withdrawal criteria may have continued ramucirumab monotherapy every 3 weeks. The primary endpoint was PFS at 6 months, with 80% power to detect a 6-month PFS rate of at least 55%. RESULTS: The 6-month PFS rate was 59.0% and the objective response rate was 55.0%. The most common treatment-related adverse events were fatigue, peripheral neuropathy, nausea, epistaxis, and myalgia. Single-nucleotide polymorphism (SNP) rs2981582 on the FGFR-2gene had significant associations with improved overall survival, PFS, and best overall response (p values without multiplicity adjustment were 0.0059, 0.0429, and 0.0392, respectively). CONCLUSION: Ramucirumab in combination with paclitaxel-carboplatin resulted in a 6-month PFS rate and safety profile that compared favorably with the historical control. In addition, no deaths were associated with this treatment. Furthermore, we describe an association of SNP on FGFR-2 gene with survival and response. These findings warrant further clinical investigation in patients with NSCLC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Carboplatina/administração & dosagem , Carboplatina/farmacocinética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Paclitaxel/administração & dosagem , Paclitaxel/farmacocinética , Ramucirumab
8.
Lancet ; 384(9944): 665-73, 2014 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-24933332

RESUMO

BACKGROUND: Ramucirumab is a human IgG1 monoclonal antibody that targets the extracellular domain of VEGFR-2. We aimed to assess efficacy and safety of treatment with docetaxel plus ramucirumab or placebo as second-line treatment for patients with stage IV non-small-cell-lung cancer (NSCLC) after platinum-based therapy. METHODS: In this multicentre, double-blind, randomised phase 3 trial (REVEL), we enrolled patients with squamous or non-squamous NSCLC who had progressed during or after a first-line platinum-based chemotherapy regimen. Patients were randomly allocated (1:1) with a centralised, interactive voice-response system (stratified by sex, region, performance status, and previous maintenance therapy [yes vs no]) to receive docetaxel 75 mg/m(2) and either ramucirumab (10 mg/kg) or placebo on day 1 of a 21 day cycle until disease progression, unacceptable toxicity, withdrawal, or death. The primary endpoint was overall survival in all patients allocated to treatment. We assessed adverse events according to treatment received. This study is registered with ClinicalTrials.gov, number NCT01168973. FINDINGS: Between Dec 3, 2010, and Jan 24, 2013, we screened 1825 patients, of whom 1253 patients were randomly allocated to treatment. Median overall survival was 10·5 months (IQR 5·1-21·2) for 628 patients allocated ramucirumab plus docetaxel and 9·1 months (4·2-18·0) for 625 patients who received placebo plus docetaxel (hazard ratio 0·86, 95% CI 0·75-0·98; p=0·023). Median progression-free survival was 4·5 months (IQR 2·3-8·3) for the ramucirumab group compared with 3·0 months (1·4-6·9) for the control group (0·76, 0·68-0·86; p<0·0001). We noted treatment-emergent adverse events in 613 (98%) of 627 patients in the ramucirumab safety population and 594 (95%) of 618 patients in the control safety population. The most common grade 3 or worse adverse events were neutropenia (306 patients [49%] in the ramucirumab group vs 246 [40%] in the control group), febrile neutropenia (100 [16%] vs 62 [10%]), fatigue (88 [14%] vs 65 [10%]), leucopenia (86 [14%] vs 77 [12%]), and hypertension (35 [6%] vs 13 [2%]). The numbers of deaths from adverse events (31 [5%] vs 35 [6%]) and grade 3 or worse pulmonary haemorrhage (eight [1%] vs eight [1%]) did not differ between groups. Toxicities were manageable with appropriate dose reductions and supportive care. INTERPRETATION: Ramucirumab plus docetaxel improves survival as second-line treatment of patients with stage IV NSCLC. FUNDING: Eli Lilly.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/patologia , Progressão da Doença , Docetaxel , Método Duplo-Cego , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Placebos , Platina , Qualidade de Vida , Taxa de Sobrevida , Taxoides/administração & dosagem , Ramucirumab
9.
Clin Lung Cancer ; 13(6): 505-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22853980

RESUMO

This article describes the treatment rationale and study-related procedures for the A Randomized, Double-Blind, Phase 3 Study of Docetaxel and Ramucirumab Versus Docetaxel and Placebo in the Treatment of Stage IV Non-Small-Cell Lung Cancer Following Disease Progression after One Prior Platinum-Based Therapy (REVEL) study (I4T-MC-JVBA; ClinicalTrials.govNCT01168973). This international, randomized, placebo-controlled, double-blinded phase III trial examines the efficacy and safety of ramucirumab treatment administered in combination with docetaxel, as compared with docetaxel administered with placebo, in patients with stage IV non-small-cell lung cancer (NSCLC) whose disease progressed during or after first-line platinum-based chemotherapy with or without maintenance treatment. The primary end point is overall survival; secondary end points include progression-free survival, objective response rate, disease control rate, patient-reported outcomes, and assessment of safety and tolerability of ramucirumab. Eligible patients (enrollment N = 1242) are randomized at a 1:1 ratio to receive either docetaxel (75 mg/m(2)) plus ramucirumab (10 mg/kg) (Arm A) or docetaxel (75 mg/m(2)) plus placebo (Arm B). Both drugs are administered via intravenous infusion once every 3 weeks until evidence of disease progression, unacceptable toxicity, noncompliance, or patient's consent withdrawal. Efficacy and safety will be compared between the study arms and in patient subgroups including patients with nonsquamous versus squamous tumor histology and patients who received prior bevacizumab treatment. Multiple blood and tumor tissue biomarker samples are collected during the study. The goal of the REVEL study is to demonstrate that ramucirumab in combination with docetaxel improves overall survival of patients with NSCLC with progressive disease after first-line therapy, and to advance our knowledge of the role of angiogenesis blockade in patients with NSCLC by identifying patients who are likely to experience maximum benefit based on extensive clinical biomarker correlative analysis.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Taxoides/uso terapêutico , Adulto , Anticorpos Monoclonais Humanizados , Progressão da Doença , Docetaxel , Método Duplo-Cego , Humanos , Projetos de Pesquisa , Análise de Sobrevida , Ramucirumab
10.
Proc Natl Acad Sci U S A ; 108(44): 18044-8, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22025722

RESUMO

Long-term humoral immunity is maintained by the formation of high-affinity class-switched memory B cells and long-lived antibody-secreting plasma cells. In healthy humans, a substantial fraction of IgG-positive memory B cells express self-reactive and polyreactive IgG antibodies that frequently develop by somatic mutations. Whether self- and polyreactive IgG-secreting B cells are also tolerated in the long-lived plasma cell pool is not known. To address this question, we cloned and expressed the Ig genes from 177 IgG-producing bone marrow plasma cells of four healthy donors. All antibodies were highly mutated but the frequency of self- and polyreactive IgG antibodies was significantly lower than that found in circulating memory B cells. The data suggest that in contrast to the development of memory B cells, entry into the bone marrow plasma cell compartment requires previously unappreciated selective regulation by mechanisms that limit the production of self- and polyreactive serum IgG antibodies.


Assuntos
Linfócitos B/imunologia , Células da Medula Óssea/imunologia , Imunoglobulina G/imunologia , Memória Imunológica , Plasmócitos/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Reação em Cadeia da Polimerase
11.
J Immunol Methods ; 329(1-2): 112-24, 2008 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17996249

RESUMO

We have developed an efficient strategy that combines immunoglobulin (Ig) gene repertoire analysis and Ig reactivity profiling at the single cell level. Based on surface marker expression individual cells at different stages of human B cell development are isolated by fluorescence-activated cell sorting. For each cell Ig heavy and corresponding Ig light chain gene transcripts are amplified by nested RT-PCR and cloned into eukaryotic expression vectors to produce monoclonal human antibodies of the same specificity in vitro. All reactions are performed in 96-well plates and allow cloning of large numbers of Ig genes. The recombinant antibodies are tested for reactivity with diverse self- and non-self antigens and the reactivity profile can be directly linked to the complete Ig heavy and Ig light chain gene sequence information that is obtained as part of the cloning strategy. In summary, our method to clone and express human monoclonal antibodies is unbiased, highly efficient, requires only small cell numbers and the recombinant antibodies allow direct conclusions on the frequency of specific human B cells in a diverse repertoire.


Assuntos
Anticorpos Monoclonais/biossíntese , Linfócitos B/imunologia , Clonagem Molecular , Vetores Genéticos , Imunoglobulina G/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Anticorpos Monoclonais/genética , Especificidade de Anticorpos , Sequência de Bases , Linhagem Celular , Separação Celular , Células Cultivadas , Reações Cruzadas , Citometria de Fluxo , Humanos , Imunoglobulina G/genética , Cadeias Pesadas de Imunoglobulinas/biossíntese , Cadeias Leves de Imunoglobulina/biossíntese , Dados de Sequência Molecular , Proteínas Recombinantes/biossíntese , Transfecção
12.
Curr Opin Rheumatol ; 19(5): 421-6, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17762605

RESUMO

PURPOSE OF REVIEW: Significant progress has been made over recent years in uncovering the B-cell tolerance mechanisms that control development of autoreactive antibodies. This review examines current knowledge on the regulation and selection of autoreactive B cells in mouse models, and in healthy humans and patients with autoimmune disorders. RECENT FINDINGS: Autoreactive B cells undergo stringent selection either in the bone marrow or peripheral circulation by deletion, induction of anergy, or receptor editing. There is growing evidence that receptor editing represents the primary physiologic B-cell tolerance mechanism. Several checkpoints against autoreactive B cells have been established in bone marrow and peripheral blood of healthy humans. Recent studies demonstrate that some autoimmune disorders are associated with several alterations in B-cell tolerance checkpoints and often lead to a greater number of autoreactive B cells in the circulation. SUMMARY: Discovering the precise nature of B-cell tolerance alterations in patients with autoimmune diseases will lead to the identification of new targets for therapeutic interventions in patients with these disorders.


Assuntos
Autoanticorpos/imunologia , Doenças Autoimunes/imunologia , Tolerância Imunológica/imunologia , Animais , Linfócitos B/imunologia , Humanos , Switching de Imunoglobulina , Camundongos , Tolerância a Antígenos Próprios/imunologia
13.
Immunity ; 26(2): 205-13, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17306569

RESUMO

More than half of the nascent B cells in humans initially express autoreactive antibodies. However, most of these autoantibodies are removed from the repertoire at two checkpoints before maturation into naive B cells. A third checkpoint excludes remaining autoantibodies from the antigen-experienced IgM(+) memory B cell pool. Nevertheless, low-affinity self-reactive antibodies are frequently found in the serum of normal humans. To determine the source of these antibodies, we cloned and expressed antibodies from circulating human IgG(+) memory B cells. Surprisingly, we found that self-reactive antibodies including anti-nuclear antibodies were frequently expressed by IgG(+) memory B cells in healthy donors. Most of these antibodies were created de novo by somatic hypermutation during the transition between mature naive and IgG(+) memory B cells. We conclude that deregulation of self-reactive IgG(+) memory B cells may be associated with autoimmunity.


Assuntos
Autoanticorpos/imunologia , Autoimunidade/imunologia , Linfócitos B/imunologia , Memória Imunológica , Afinidade de Anticorpos , Autoanticorpos/análise , Ensaio de Imunoadsorção Enzimática , Humanos , Reação em Cadeia da Polimerase , Hipermutação Somática de Imunoglobulina
14.
J Exp Med ; 203(10): 2255-61, 2006 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-16966430

RESUMO

A majority of the antibodies expressed by nascent B cells in healthy humans are self-reactive, but most of these antibodies are removed from the repertoire during B cell development. In contrast, untreated systemic lupus erythematosus (SLE) patients fail to remove many of the self-reactive and polyreactive antibodies from the naive repertoire. Here, we report that SLE patients in clinical remission continue to produce elevated numbers of self-reactive and polyreactive antibodies in the mature naive B cell compartment, but the number of B cells expressing these antibodies is lower than in patients with active disease. Our finding that abnormal levels of self-reactive mature naive B cells persist in the majority of patients in clinical remission suggests that early checkpoint abnormalities are an integral feature of SLE.


Assuntos
Autoanticorpos/imunologia , Linfócitos B/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Adolescente , Criança , Ensaio de Imunoadsorção Enzimática , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Genes de Imunoglobulinas/genética , Humanos , Masculino , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
J Exp Med ; 203(2): 393-400, 2006 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-16446381

RESUMO

Autoantibodies are removed from the repertoire at two checkpoints during B cell development in the bone marrow and the periphery. Despite these checkpoints, up to 20% of the antibodies expressed by mature naive B cells in healthy humans show low levels of self-reactivity. To determine whether self-reactive antibodies are also part of the antigen-experienced memory B cell compartment, we analyzed recombinant antibodies cloned from single circulating human IgM+ memory B cells. Cells expressing antibodies specific for individual bacterial polysaccharides were expanded in the IgM+ memory compartment. In contrast, B cells expressing self-reactive and broadly bacterially reactive antibodies were removed from the repertoire in the transition from naive to IgM+ memory B cell. Selection against self-reactive antibodies was implemented before the onset of somatic hypermutation. We conclude that a third checkpoint selects against self-reactivity during IgM+ memory B cell development in humans.


Assuntos
Autoanticorpos/biossíntese , Linfócitos B/imunologia , Linfócitos B/metabolismo , Diferenciação Celular/imunologia , Imunoglobulina M/biossíntese , Memória Imunológica , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/metabolismo , Linfócitos B/citologia , Linfócitos B/microbiologia , Células Cultivadas , Humanos , Cadeias Pesadas de Imunoglobulinas/biossíntese , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/biossíntese , Região Variável de Imunoglobulina/genética , Polissacarídeos Bacterianos/imunologia , Polissacarídeos Bacterianos/metabolismo , Fase de Repouso do Ciclo Celular/imunologia , Proteína Estafilocócica A/imunologia
16.
J Exp Med ; 201(5): 703-11, 2005 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-15738055

RESUMO

A cardinal feature of systemic lupus erythematosus (SLE) is the development of autoantibodies. The first autoantibodies described in patients with SLE were those specific for nuclei and DNA, but subsequent work has shown that individuals with this disease produce a panoply of different autoantibodies. Thus, one of the constant features of SLE is a profound breakdown in tolerance in the antibody system. The appearance of self-reactive antibodies in SLE precedes clinical disease, but where in the B cell pathway tolerance is first broken has not been defined. In healthy humans, autoantibodies are removed from the B cell repertoire in two discrete early checkpoints in B cell development. We found these checkpoints to be defective in three adolescent patients with SLE. 25-50% of the mature naive B cells in SLE patients produce self-reactive antibodies even before they participate in immune responses as compared with 5-20% in controls. We conclude that SLE is associated with abnormal early B cell tolerance.


Assuntos
Linfócitos B/imunologia , Tolerância Imunológica/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Adolescente , Autoanticorpos/imunologia , Linfócitos B/patologia , Linhagem Celular , Criança , Feminino , Humanos , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/patologia , Masculino , Fosfatidilserinas/imunologia , Fosfatidilserinas/metabolismo
17.
Ann N Y Acad Sci ; 1062: 165-74, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16461799

RESUMO

Antibodies are protective effector molecules in the body's immune defense against pathogens. However, if directed against the body's own tissues or organs, antibodies can also play a role in the pathogenesis of autoimmune disease. Here, we discuss our data on how autoreactive antibodies are regulated in healthy humans and how a failure to establish self-tolerance during early B-cell development in patients with systemic lupus erythematosus may predispose to the development of this autoimmune disease.


Assuntos
Subpopulações de Linfócitos B/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Tolerância a Antígenos Próprios/imunologia , Estudos de Casos e Controles , Humanos
18.
Science ; 301(5638): 1374-7, 2003 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-12920303

RESUMO

During B lymphocyte development, antibodies are assembled by random gene segment reassortment to produce a vast number of specificities. A potential disadvantage of this process is that some of the antibodies produced are self-reactive. We determined the prevalence of self-reactive antibody formation and its regulation in human B cells. A majority (55 to 75%) of all antibodies expressed by early immature B cells displayed self-reactivity, including polyreactive and anti-nuclear specificities. Most of these autoantibodies were removed from the population at two discrete checkpoints during B cell development. Inefficient checkpoint regulation would lead to substantial increases in circulating autoantibodies.


Assuntos
Autoanticorpos/biossíntese , Linfócitos B/imunologia , Anticorpos Antinucleares/biossíntese , Anticorpos Antinucleares/imunologia , Diversidade de Anticorpos , Especificidade de Anticorpos , Autoanticorpos/imunologia , Linfócitos B/citologia , Linfócitos B/fisiologia , Diferenciação Celular , Linhagem Celular , Regiões Determinantes de Complementaridade/química , Regiões Determinantes de Complementaridade/imunologia , Citosol/imunologia , Genes de Imunoglobulinas , Humanos , Cadeias Pesadas de Imunoglobulinas/química , Cadeias Pesadas de Imunoglobulinas/imunologia , Recombinação Genética , Seleção Genética , Células Tumorais Cultivadas
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