Anti-idiotypes against a monoclonal anti-haloperidol antibody bind to dopamine receptor

International Nuclear Information System (INIS)

Elazar, Z.; Kanety, H.; Schreiber, M.; Fuchs, S.

1988-01-01

Anti-idiotypic antibodies were raised in rabbits by immunization with a monoclonal anti-haloperidol antibody. Some of these anti-idiotypic antibodies bind in a concentration dependent manner to bovine striatal membranes. Following affinity purification, these antibodies inhibit haloperidol binding to striatal membranes and deplete [ 3 H]-spiperone binding sites from a solubilized preparation of striatal membranes. It is thus concluded that these anti-idiotypic antibodies are an internal image of haloperidol and as such can interact with D 2 -dopamine receptors

Biodistribution mechanisms of therapeutic monoclonal antibodies in health and disease.

Science.gov (United States)

Tabrizi, Mohammad; Bornstein, Gadi Gazit; Suria, Hamza

2010-03-01

The monoclonal antibody market continues to witness an impressive rate of growth and has become the leading source of expansion in the biologic segment within the pharmaceutical industry. Currently marketed monoclonal antibodies target a diverse array of antigens. These antigens are distributed in a variety of tissues such as tumors, lungs, synovial fluid, psoriatic plaques, and lymph nodes. As the concentration of drug at the proximity of the biological receptor determines the magnitude of the observed pharmacological responses, a significant consideration in effective therapeutic application of monoclonal antibodies is a thorough understanding of the processes that regulate antibody biodistribution. Monoclonal antibody distribution is affected by factors such as molecular weight, blood flow, tissue and tumor heterogeneity, structure and porosity, target antigen density, turnover rate, and the target antigen expression profile.

Establishment of H2Mab-119, an Anti-Human Epidermal Growth Factor Receptor 2 Monoclonal Antibody, Against Pancreatic Cancer.

Science.gov (United States)

Yamada, Shinji; Itai, Shunsuke; Nakamura, Takuro; Chang, Yao-Wen; Harada, Hiroyuki; Suzuki, Hiroyoshi; Kaneko, Mika K; Kato, Yukinari

2017-12-01

Human epidermal growth factor receptor 2 (HER2) is overexpressed in breast cancer and is associated with poor clinical outcomes. In addition, HER2 expression has been reported in other cancers, such as gastric, colorectal, lung, and pancreatic cancers. An anti-HER2 humanized antibody, trastuzumab, leads to significant survival benefits in patients with HER2-overexpressing breast cancers and gastric cancers. Herein, we established a novel anti-HER2 monoclonal antibody (mAb), H 2 Mab-119 (IgG 1 , kappa), and characterized its efficacy against pancreatic cancers using flow cytometry, Western blot, and immunohistochemical analyses. H 2 Mab-119 reacted with pancreatic cancer cell lines, such as KLM-1, Capan-2, and MIA PaCa-2, but did not react with PANC-1 in flow cytometry analysis. Western blot analysis also revealed a moderate signal for KLM-1 and a weak signal for MIA PaCa-2, although H 2 Mab-119 reacted strongly with LN229/HER2 cells. Finally, immunohistochemical analyses with H 2 Mab-119 revealed sensitive and specific reactions against breast and colon cancers but did not react with pancreatic cancers, indicating that H 2 Mab-119 is useful for detecting HER2 overexpression in pancreatic cancers using flow cytometry and Western blot analyses.

Panel of monoclonal antibodies to sperm surface proteins as a tool for monitoring localization and identification of sperm-zona pellucida receptors

Czech Academy of Sciences Publication Activity Database

Zigo, Michal; Dorosh, Andriy; Pohlová, Alžběta; Jonáková, Věra; Šulc, Miroslav; Maňásková-Postlerová, Pavla

March, č. 359 (2015), s. 895-908 ISSN 0302-766X R&D Projects: GA ČR(CZ) GA14-05547S; GA MŠk(CZ) ED1.1.00/02.0109; GA ČR(CZ) GAP503/12/1834 Institutional research plan: CEZ:AV0Z50520701 Institutional support: RVO:86652036 ; RVO:61388971 Keywords : zona pellucida-binding receptors * monoclonal antibodies against sperm surface proteins * sperm surface proteins * RAB-2A * lactahedrin P47 Subject RIV: CE - Biochemistry Impact factor: 2.948, year: 2015

Expression of epidermal growth factor receptors in human endometrial carcinoma

DEFF Research Database (Denmark)

Nyholm, H C; Nielsen, Anette Lynge; Ottesen, B

1993-01-01

Little data exist on the expression of epidermal growth factor receptors (EGF-Rs) in human endometrial cancer. EGF-R status was studied in 65 patients with endometrial carcinomas and in 26 women with nonmalignant postmenopausal endometria, either inactive/atrophic endometrium or adenomatous...... hyperplasia. EGF-R was identified on frozen tissue sections by means of an indirect immunoperoxidase technique with a monoclonal antibody against the external domain of the EGF-R. Seventy-one percent of the carcinomas expressed positive EGF-R immunoreactivity. In general, staining was most prominent...

Monoclonal anti-human factor VII antibodies. Detection in plasma of a second protein antigenically and genetically related to factor VII.

OpenAIRE

Broze, G J; Hickman, S; Miletich, J P

1985-01-01

Several murine monoclonal anti-human Factor VII antibodies were produced using hybridoma technology. Two noncompetitive monoclonal antibodies were used to examine by Western blotting the Factor VII cross-reactive material (CRM) in normal human plasma and three commercially available congenitally Factor VII-deficient plasmas, and to construct a facile "sandwich" immunoassay for plasma Factor VII. A second, previously undescribed, form of Factor VII CRM was detected in human plasma, which on We...

Personalized Radiation Oncology: Epidermal Growth Factor Receptor and Other Receptor Tyrosine Kinase Inhibitors.

Science.gov (United States)

Higgins, Geoff S; Krause, Mechthild; McKenna, W Gillies; Baumann, Michael

Molecular biomarkers are currently evaluated in preclinical and clinical studies in order to establish predictors for treatment decisions in radiation oncology. The receptor tyrosine kinases (RTK) are described in the following text. Among them, the most data are available for the epidermal growth factor receptor (EGFR) that plays a major role for prognosis of patients after radiotherapy, but seems also to be involved in mechanisms of radioresistance, specifically in repopulation of tumour cells between radiotherapy fractions. Monoclonal antibodies against the EGFR improve locoregional tumour control and survival when applied during radiotherapy, however, the effects are heterogeneous and biomarkers for patient selection are warranted. Also other RTK´s such as c-Met and IGF-1R seem to play important roles in tumour radioresistance. Beside the potential to select patients for molecular targeting approaches combined with radiotherapy, studies are also needed to evluate radiotherapy adaptation approaches for selected patients, i.e. adaptation of radiation dose, or, more sophisticated, of target volumes.

Monoclonal antibodies to human factor VII: a one step immunoradiometric assay for VII:Ag.

OpenAIRE

Takase, T; Tuddenham, E G; Chand, S; Goodall, A H

1988-01-01

Three mouse monoclonal antibodies (RFF-VII/1, RFF-VII/2, and RFF-VII/3) which bind specifically to different epitopes on human factor VII antigen were raised. Two of the antibodies, RFF-VII/1 and RFF-VII/2, bound strongly to factor VII antigen (VII:Ag), but only RFF-VII/1 and RFF-VII/3 were potent inhibitors of factor VII coagulation activity (VII:C). RFF-VII/1 and RFF-VII/2 were used in a one step, double monoclonal immunoradiometric assay for VII:Ag. This was highly reproducible and detecte...

ERBB oncogene proteins as targets for monoclonal antibodies.

Science.gov (United States)

Polanovski, O L; Lebedenko, E N; Deyev, S M

2012-03-01

General properties of the family of tyrosine kinase ERBB receptors are considered in connection with their role in the generation of cascades of signal transduction in normal and tumor cells. Causes of acquisition of oncogene features by genes encoding these receptors and their role in tumorigenesis are analyzed. Anti-ERBB monoclonal antibodies approved for therapy are described in detail, and mechanisms of their antitumor activity and development of resistance to them are reviewed. The existing and the most promising strategies for creating and using monoclonal antibodies and their derivatives for therapy of cancer are discussed.

Neutron capture therapy of epidermal growth factor receptor (EGFR)vIII positive gliomas using boronated monoclonal antibody L8A4

International Nuclear Information System (INIS)

Yang, Weilian; Barth, Rolf F.; Wu, Gong

2006-01-01

The purpose of the present study was to evaluate the EGFRvIII specific monoclonal antibody, L8A4 as a boron delivery agent for NCT of the receptor (+) rat glioma, F98 npEGFRvIII . A heavily boronated polyamidoamine (PAMAM) dendrimer (BD) was linked to L8A4 by means of heterobifunctional reagents. Wild type (F98 WT ) receptor(-) or EGFRvIII human gene transfected receptor(+) F98 npEGFRvIII glioma cells were implanted into the brains of Fischer rats. Biodistribution studies were initiated 14 d later. Animals received 125 I-labeled BD-L8A4 by either convection enhanced delivery (CED) or intratumoral(i.t.) injection and were euthanized 6, 12, 24 or 48 h later. At 6 h following CED, equivalent amounts of the bioconjugate were detected in receptor(+) and (-) tumors, but by 24 h the amounts retained by receptor(+) gliomas were 60.1% following CED and 43.7% following i.t. injection, compared to 14.6% ID/g by receptor(-) tumors. Tumor boron concentrations were 32.7 and 44.5 μg/g, respectively, for BD-L8A4 alone or in combination with i.v. BPA. BNCT was carried out at the MITR-II Reactor 24 h after CED of BD-L8A4 (∼40 μg 10 B/∼750 μg protein) and 2.5 h after i.v. injection of BPA (500 mg/kg). Rats that received BD-L8A4 alone or in combination with BPA had mean survival times of 70.4 and 85d, respectively, with 20% and 10% long term survivors, respectively, compared to 40.1 d for i.v. BPA and 30.3 and 26.3 d for irradiated and untreated controls, respectively. These data convincingly demonstrate the therapeutic efficacy of molecular targeting of EGFRvIII and should provide a platform for the future development of combinations of high and low molecular weight delivery agents for BNCT of brain tumors. (author)

Comparison of monoclonal antibodies and tritiated ligands for estrogen receptor assays in 241 breast cancer cytosols

International Nuclear Information System (INIS)

Goussard, J.; Lechevrel, C.; Martin, P.M.; Roussel, G.

1986-01-01

Estrogen receptor determinations have been performed on 241 cytosols from 160 breast cancer tumors using both radioactive ligands ([ 3 H]-estradiol, [3H]R2858) and monoclonal antibodies (Abbott ER-EIA Kit) to compare the two methods and to evaluate the clinical usefulness of the new immunological, simplified assay. Intra- and interassay reproducibility of the enzyme immunoassay (EIA) method was studied during a 6-month period on 35 standard curves with 4 different batches of monoclonal antibodies. Intraassay coefficients of variation studied on duplicates were smaller than 5% in most cases and reproducibility of the curves showed coefficients of variation lower than 10% except for standard 0 and 5 fmol/ml. Pooled cytosols used as control for the dextran coated charcoal method had interassay variation coefficients between 3.8 and 11.4%. Reproducibility has been studied on clinical specimens assayed twice at two different periods with either EIA or dextran coated charcoal methods. Slopes obtained were 1.05 and 0.96, respectively. A good stability of EIA results was obtained with protein concentrations in the range 4-0.15 mg/ml cytosol. No significant effects of dithiothreitol or monothioglycerol (1 mM) on EIA and dextran coated charcoal assay were observed. Eighty breast cancer cytosols were assayed with both EIA and Scatchard analysis. The slope of the regression curve obtained was 1.04 (r = 0.963). Cytosols were assayed by EIA and by a saturating concentration of tritiated ligand (5 nM). With 153 cytosols the EIA/5 nM slope was 1.34 (r = 0.978). This slope can be compared with the slope Scatchard/5 nM obtained with 90 cytosols: 1.29 (r = 0.985). Absence of cross-reactivity of monoclonal ER antibodies with progesterone receptor was observed

Novel anti-HER2 monoclonal antibodies: synergy and antagonism with tumor necrosis factor-α

Directory of Open Access Journals (Sweden)

Ceran Ceyhan

2012-10-01

Full Text Available Abstract Background One-third of breast cancers display amplifications of the ERBB2 gene encoding the HER2 kinase receptor. Trastuzumab, a humanized antibody directed against an epitope on subdomain IV of the extracellular domain of HER2 is used for therapy of HER2-overexpressing mammary tumors. However, many tumors are either natively resistant or acquire resistance against Trastuzumab. Antibodies directed to different epitopes on the extracellular domain of HER2 are promising candidates for replacement or combinatorial therapy. For example, Pertuzumab that binds to subdomain II of HER2 extracellular domain and inhibits receptor dimerization is under clinical trial. Alternative antibodies directed to novel HER2 epitopes may serve as additional tools for breast cancer therapy. Our aim was to generate novel anti-HER2 monoclonal antibodies inhibiting the growth of breast cancer cells, either alone or in combination with tumor necrosis factor-α (TNF-α. Methods Mice were immunized against SK-BR-3 cells and recombinant HER2 extracellular domain protein to produce monoclonal antibodies. Anti-HER2 antibodies were characterized with breast cancer cell lines using immunofluorescence, flow cytometry, immunoprecipitation, western blot techniques. Antibody epitopes were localized using plasmids encoding recombinant HER2 protein variants. Antibodies, either alone or in combination with TNF-α, were tested for their effects on breast cancer cell proliferation. Results We produced five new anti-HER2 monoclonal antibodies, all directed against conformational epitope or epitopes restricted to the native form of the extracellular domain. When tested alone, some antibodies inhibited modestly but significantly the growth of SK-BR-3, BT-474 and MDA-MB-361 cells displaying ERBB2 amplification. They had no detectable effect on MCF-7 and T47D cells lacking ERBB2 amplification. When tested in combination with TNF-α, antibodies acted synergistically on SK-BR-3 cells

Location of Primary Tumor and Benefit From Anti-Epidermal Growth Factor Receptor Monoclonal Antibodies in Patients With RAS and BRAF Wild-Type Metastatic Colorectal Cancer

Science.gov (United States)

Moretto, Roberto; Cremolini, Chiara; Rossini, Daniele; Pietrantonio, Filippo; Battaglin, Francesca; Mennitto, Alessia; Bergamo, Francesca; Loupakis, Fotios; Marmorino, Federica; Berenato, Rosa; Marsico, Valentina Angela; Caporale, Marta; Antoniotti, Carlotta; Masi, Gianluca; Salvatore, Lisa; Borelli, Beatrice; Fontanini, Gabriella; Lonardi, Sara; De Braud, Filippo

2016-01-01

Introduction. Right- and left-sided colorectal cancers (CRCs) differ in clinical and molecular characteristics. Some retrospective analyses suggested that patients with right-sided tumors derive less benefit from anti-epidermal growth factor receptor (EGFR) antibodies; however, molecular selection in those studies was not extensive. Patients and Methods. Patients with RAS and BRAF wild-type metastatic CRC (mCRC) who were treated with single-agent anti-EGFRs or with cetuximab-irinotecan (if refractory to previous irinotecan) were included in the study. Differences in outcome between patients with right- and left-sided tumors were investigated. Results. Of 75 patients, 14 and 61 had right- and left-sided tumors, respectively. None of the right-sided tumors responded according to RECIST, compared with 24 left-sided tumors (overall response rate: 0% vs. 41%; p = .0032), and only 2 patients with right-sided tumors (15%) versus 47 patients with left-sided tumors (80%) achieved disease control (p < .0001). The median duration of progression-free survival was 2.3 and 6.6 months in patients with right-sided and left-sided tumors, respectively (hazard ratio: 3.97; 95% confidence interval: 2.09–7.53; p < .0001). Conclusion. Patients with right-sided RAS and BRAF wild-type mCRC seemed to derive no benefit from single-agent anti-EGFRs. Implications for Practice: Right- and left-sided colorectal tumors have peculiar epidemiological and clinicopathological characteristics, distinct gene expression profiles and genetic alterations, and different prognoses. This study assessed the potential predictive impact of primary tumor site with regard to anti-epidermal growth factor receptor (EGFR) monoclonal antibody treatment in patients with RAS and BRAF wild-type metastatic colorectal cancer. The results demonstrated the lack of activity of anti-EGFRs in RAS and BRAF wild-type, right-sided tumors, thus suggesting a potential role for primary tumor location in driving treatment choices

Diagnostic of tumours of epithelial origin with the monoclonal antibody IOR EGF/R3 murino

International Nuclear Information System (INIS)

Ramos, M.

1997-01-01

Despite of the advantages on anti tumoral therapy, the cancer of epithelial origin constitutes one of the first causes of death worldwide. That kind of tumors have a 10-30-fold overexpression of the epidermal growth factor receptor (EGFr). Monoclonal antibody ior egf/r3 is a lgG2a, which recognizes the epidermal growth factor receptor. The aim of the present work was the evaluate the diagnostic efficacy of the 99m Tc-labelled ior egf/r3 for the detection of epithelial derived tumors, its metastasis and its recurrences

Development and validation of receptor occupancy pharmacodynamic assays used in the clinical development of the monoclonal antibody vedolizumab.

Science.gov (United States)

Wyant, Tim; Estevam, Jose; Yang, Lili; Rosario, Maria

2016-03-01

Vedolizumab is a monoclonal antibody approved for use in ulcerative colitis and Crohn's disease. By specifically binding to α4 β7 integrin, vedolizumab prevents trafficking of lymphocytes to the gut, thereby interfering with disease pathology. During the clinical development program, the pharmacodynamic effect of vedolizumab was evaluated by 2 flow cytometry receptor occupancy assays: act-1 (ACT-1) and mucosal addressin cell adhesion molecule-1 (MAdCAM-1). Here we describe the development and validation of these assays. The ACT-1 assay is a receptor occupancy free-site assay that uses a monoclonal antibody with the same binding epitope as vedolizumab to detect free (unbound) sites on α4 β7 integrin. The MAdCAM-1 assay used a soluble version of the natural ligand for α4 β7 integrin to detect free sites. The assays were validated using a fit-for-purpose approach throughout the clinical development of vedolizumab. Both the ACT-1 assay and the MAdCAM-1 assay demonstrated acceptable reproducibility and repeatability. The assays were sufficiently stable to allow for clinical use. During clinical testing the assays demonstrated that vedolizumab was able to saturate peripheral cells at all doses tested. Two pharmacodynamic receptor occupancy assays were developed and validated to assess the effect of vedolizumab on peripheral blood cells. The results of these assays demonstrated the practical use of flow cytometry to examine pharmacodynamic response in clinical trials. © 2015 International Clinical Cytometry Society.

Generation and Characterization of Novel Human IRAS Monoclonal Antibodies

Directory of Open Access Journals (Sweden)

Bo Wang

2009-01-01

Full Text Available Imidazoline receptors were first proposed by Bousquet et al., when they studied antihypertensive effect of clonidine. A strong candidate for I1R, known as imidazoline receptor antisera-selected protein (IRAS, has been cloned from human hippocampus. We reported that IRAS mediated agmatine-induced inhibition of opioid dependence in morphine-dependent cells. To elucidate the functional and structure properties of I1R, we developed the newly monoclonal antibody against the N-terminal hIRAS region including the PX domain (10–120aa through immunization of BALB/c mice with the NusA-IRAS fusion protein containing an IRAS N-terminal (10–120aa. Stable hybridoma cell lines were established and monoclonal antibodies specifically recognized full-length IRAS proteins in their native state by immunoblotting and immunoprecipitation. Monoclonal antibodies stained in a predominantly punctate cytoplasmic pattern when applied to IRAS-transfected HEK293 cells by indirect immunofluorescence assays and demonstrated excellent reactivity in flow immunocytometry. These monoclonal antibodies will provide powerful reagents for the further investigation of hIRAS protein functions.

Developmental regulation of human truncated nerve growth factor receptor

Energy Technology Data Exchange (ETDEWEB)

DiStefano, P.S.; Clagett-Dame, M.; Chelsea, D.M.; Loy, R. (Abbott Laboratories, Abbott Park, IL (USA))

1991-01-01

Monoclonal antibodies (designated XIF1 and IIIG5) recognizing distinct epitopes of the human truncated nerve growth factor receptor (NGF-Rt) were used in a two-site radiometric immunosorbent assay to monitor levels of NGF-Rt in human urine as a function of age. Urine samples were collected from 70 neurologically normal subjects ranging in age from 1 month to 68 years. By using this sensitive two-site radiometric immunosorbent assay, NGF-Rt levels were found to be highest in urine from 1-month old subjects. By 2.5 months, NGF-Rt values were half of those seen at 1 month and decreased more gradually between 0.5 and 15 years. Between 15 and 68 years, urine NGF-Rt levels were relatively constant at 5% of 1-month values. No evidence for diurnal variation of adult NGF-Rt was apparent. Pregnant women in their third trimester showed significantly elevated urine NGF-Rt values compared with age-matched normals. Affinity labeling of NGF-Rt with 125I-NGF followed by immunoprecipitation with ME20.4-IgG and gel autoradiography indicated that neonatal urine contained high amounts of truncated receptor (Mr = 50 kd); decreasingly lower amounts of NGF-Rt were observed on gel autoradiograms with development, indicating that the two-site radiometric immunosorbent assay correlated well with the affinity labeling technique for measuring NGF-Rt. NGF-Rt in urines from 1-month-old and 36-year-old subjects showed no differences in affinities for NGF or for the monoclonal antibody IIIG5. These data show that NGF-Rt is developmentally regulated in human urine, and are discussed in relation to the development and maturation of the peripheral nervous system.

Developmental regulation of human truncated nerve growth factor receptor

International Nuclear Information System (INIS)

DiStefano, P.S.; Clagett-Dame, M.; Chelsea, D.M.; Loy, R.

1991-01-01

Monoclonal antibodies (designated XIF1 and IIIG5) recognizing distinct epitopes of the human truncated nerve growth factor receptor (NGF-Rt) were used in a two-site radiometric immunosorbent assay to monitor levels of NGF-Rt in human urine as a function of age. Urine samples were collected from 70 neurologically normal subjects ranging in age from 1 month to 68 years. By using this sensitive two-site radiometric immunosorbent assay, NGF-Rt levels were found to be highest in urine from 1-month old subjects. By 2.5 months, NGF-Rt values were half of those seen at 1 month and decreased more gradually between 0.5 and 15 years. Between 15 and 68 years, urine NGF-Rt levels were relatively constant at 5% of 1-month values. No evidence for diurnal variation of adult NGF-Rt was apparent. Pregnant women in their third trimester showed significantly elevated urine NGF-Rt values compared with age-matched normals. Affinity labeling of NGF-Rt with 125I-NGF followed by immunoprecipitation with ME20.4-IgG and gel autoradiography indicated that neonatal urine contained high amounts of truncated receptor (Mr = 50 kd); decreasingly lower amounts of NGF-Rt were observed on gel autoradiograms with development, indicating that the two-site radiometric immunosorbent assay correlated well with the affinity labeling technique for measuring NGF-Rt. NGF-Rt in urines from 1-month-old and 36-year-old subjects showed no differences in affinities for NGF or for the monoclonal antibody IIIG5. These data show that NGF-Rt is developmentally regulated in human urine, and are discussed in relation to the development and maturation of the peripheral nervous system

Establishment of EMab-134, a Sensitive and Specific Anti-Epidermal Growth Factor Receptor Monoclonal Antibody for Detecting Squamous Cell Carcinoma Cells of the Oral Cavity.

Science.gov (United States)

Itai, Shunsuke; Yamada, Shinji; Kaneko, Mika K; Chang, Yao-Wen; Harada, Hiroyuki; Kato, Yukinari

2017-12-01

Epidermal growth factor receptor (EGFR), a receptor tyrosine kinase, activates downstream signaling cascades in many tumors. In this study, we established novel anti-EGFR monoclonal antibodies (mAbs) and characterized their efficacy in flow cytometry, Western blot, and immunohistochemical analyses. We immunized mice with a combination of the extracellular domain of EGFR and EGFR-overexpressing LN229 glioblastoma cells (LN229/EGFR) and performed the first screening using enzyme-linked immunosorbent assay. Next, we selected mAbs using flow cytometry. Among 156 established clones, two mAbs, EMab-51 (IgG 1 , kappa) and EMab-134 (IgG 1 , kappa), reacted with EGFR in Western blot analysis; EMab-134 showed a much higher sensitivity compared with EMab-51. We compared the binding affinities of EMab-51 and EMab-134 using flow cytometry; the calculated K D values for EMab-51 and EMab-134 against SAS cells/HSC-2 cells were 9.2 × 10 -9 M/9.9 × 10 -9 M and 2.6 × 10 -9 M/8.3 × 10 -9 M, respectively, indicating that EMab-134 has a higher affinity to EGFR-expressing cells. Immunohistochemical analysis of EMab-51 and EMab-134 showed sensitive and specific reactions against oral cancer cells; EMab-134 demonstrated a much higher sensitivity (36/38 cases; 94.7%) to oral squamous cell carcinomas compared with EMab-51 (6/38 cases; 15.8%). This novel anti-EGFR mAb, EMab-134, could be advantageous for detecting EGFR in the pathological analysis of EGFR-expressing cancers.

Identification of endogenous opioid receptor components in rat brain using a monoclonal antibody

Energy Technology Data Exchange (ETDEWEB)

Bero, L.A.; Roy, S.; Lee, N.M.

1988-11-01

A monoclonal antibody generated against the tertiary structure of a partially purified opioid binding protein was used to probe the structure of the dynorphin and beta-endorphin receptors. The Fab fragment 3B4F11 inhibited completely the binding of 125I-beta-endorphin and (3H)dynorphin to rat brain P2 membranes with IC50 values of 26 ng/ml and 40 ng/ml, respectively. To explore further the interaction of 3B4F11 with the beta-endorphin receptor, the effect of the Fab fragment on 125I-beta-endorphin cross-linking to rat brain membranes was examined. 125I-beta-endorphin was covalently bound to three major species of approximate molecular weights 108,000, 73,000, and 49,000. The delta-selective ligand D-Pen2, D-pen5enkephalin was least effective at inhibiting the cross-linking of beta-endorphin, whereas the micro-selective ligand Tyr-D-Ala-Gly-NMe-Phe-Gly-ol and kappa-selective ligand U50488 inhibited beta-endorphin cross-linking to the 108,000 and 73,000 Da species. Both 3B4F11 and beta-endorphin prevented the covalent binding of 125I-beta-endorphin to all three labeled species. These findings suggest that micro and kappa receptor types might have some structural similarities, whereas the delta receptor type might differ in molecular size. In addition, the micro, kappa, and delta ligands might have different primary sequences, whereas their tertiary structures might share regions of molecular homology with all three receptor constituents labeled by 125I-beta-endorphin. 3B4F11 will be a valuable tool for the purification and isolation of the several components of the beta-endorphin receptor complex.

Production and radioiodination of monoclonal antibodies and its applications in nuclear medicine

International Nuclear Information System (INIS)

Toledo e Souza, I.T. de; Okada, H.

1988-12-01

The basis of the monoclonal antibody production methodology, some immunological concepts which are important for the understanding of what is a Monoclonal Antibody, its radioiodination and acceptance as receptor-specific radiopharmaceuticals in nuclear medicine are reviewed. (author) [pt

HER2-targeted therapy in breast cancer. Monoclonal antibodies and tyrosine kinase inhibitors

DEFF Research Database (Denmark)

Nielsen, Dorte Lisbet; Andersson, Michael; Kamby, Claus

2008-01-01

There is strong clinical evidence that trastuzumab, a monoclonal antibody targeting the human epidermal growth factor receptor (HER) two tyrosine kinase receptor, is an important component of first-line treatment of patients with HER2-positive metastatic breast cancer. In particular the combination...... of trastuzumab to chemotherapy improves disease-free and overall survival. The use of lapatinib, a dual tyrosine kinase inhibitor of both HER1 and HER2, in combination with capecitabine in the second-line treatment of HER2-positive patients with metastatic breast cancer previously treated with trastuzumab has...

Pharmacokinetics, biodistribution and dosimetry of 99mTc-labeled anti-human epidermal growth factor receptor humanized monoclonal antibody R3 in rats

International Nuclear Information System (INIS)

Escobar, Normando Iznaga; Morales, Alejo Morales; Duconge, Jorge; Torres, Idania Caballero; Fernandez, Eduardo; Gomez, Jose A.

1998-01-01

The pharmacokinetics, biodistribution and dosimetry of 99m Tc-labeled anti-human epidermal growth factor receptor (anti-hEGF-r) humanized monoclonal antibody (MAb) R3 was investigated following intravenous injection in normal Wistar rats. Serum disappearance curves were best fit by a two-compartment model having a mean distribution half-life (t (1(2α)) ) of 0.250 h and a mean elimination (t (1(2β)) ) of 13.89 h. Among the various organs, a little accumulation of the radiolabeled antibody was found only in kidneys. Biodistribution and dosimetry studies in humans were performed by extrapolation of the animal data to humans. Absorbed dose to normal organs and the remainder of the whole body were estimated using the medical internal radiation dose formula, and dose contributions from radioactivity in transit through the gastrointestinal tract were estimated using a compartment model. Extrapolated values of radiation absorbed dose to normal organs in rads per millicurie administered were whole body, 0.0085; lower large intestine wall, 0.0898; small intestine, 0.0530; upper large intestine wall, 0.0731; and kidneys, 0.0455. The effective dose equivalent predicted was 0.0162 rem/mCi and the effective dose was found to be 0.015 rem/mCi. On the basis of the pharmacokinetics, biodistribution and internal radiation dosimetry information obtained in this study, a diagnostic phase I clinical trial with 99m Tc-labeled humanized MAb R3 conjugate in patients should be supported

Targeting the Insulin-Like Growth Factor 1 Receptor in Ewing's Sarcoma: Reality and Expectations

Directory of Open Access Journals (Sweden)

David Olmos

2011-01-01

Full Text Available Ewing's sarcoma family of tumours comprises a group of very aggressive diseases that are potentially curable with multimodality treatment. Despite the undoubted success of current treatment, approximately 30% of patients will relapse and ultimately die of disease. The insulin-like growth factor 1 receptor (IGF-1R has been implicated in the genesis, growth, proliferation, and the development of metastatic disease in Ewing's sarcoma. In addition, IGF1-R has been validated, both in vitro and in vivo, as a potential therapeutic target in Ewing's sarcoma. Phase I studies of IGF-1R monoclonal antibodies reported several radiological and clinical responses in Ewing's sarcoma patients, and initial reports of several Phase II studies suggest that about a fourth of the patients would benefit from IGF-1R monoclonal antibodies as single therapy, with approximately 10% of patients achieving objective responses. Furthermore, these therapies are well tolerated, and thus far severe toxicity has been rare. Other studies assessing IGF-1R monoclonal antibodies in combination with traditional cytotoxics or other targeted therapies are expected. Despite, the initial promising results, not all patients benefit from IGF-1R inhibition, and consequently, there is an urgent need for the identification of predictive markers of response.

Targeting the Insulin-Like Growth Factor 1 Receptor in Ewing's Sarcoma: Reality and Expectations

Science.gov (United States)

Olmos, David; Martins, Ana Sofia; Jones, Robin L.; Alam, Salma; Scurr, Michelle; Judson, Ian R.

2011-01-01

Ewing's sarcoma family of tumours comprises a group of very aggressive diseases that are potentially curable with multimodality treatment. Despite the undoubted success of current treatment, approximately 30% of patients will relapse and ultimately die of disease. The insulin-like growth factor 1 receptor (IGF-1R) has been implicated in the genesis, growth, proliferation, and the development of metastatic disease in Ewing's sarcoma. In addition, IGF1-R has been validated, both in vitro and in vivo, as a potential therapeutic target in Ewing's sarcoma. Phase I studies of IGF-1R monoclonal antibodies reported several radiological and clinical responses in Ewing's sarcoma patients, and initial reports of several Phase II studies suggest that about a fourth of the patients would benefit from IGF-1R monoclonal antibodies as single therapy, with approximately 10% of patients achieving objective responses. Furthermore, these therapies are well tolerated, and thus far severe toxicity has been rare. Other studies assessing IGF-1R monoclonal antibodies in combination with traditional cytotoxics or other targeted therapies are expected. Despite, the initial promising results, not all patients benefit from IGF-1R inhibition, and consequently, there is an urgent need for the identification of predictive markers of response. PMID:21647361

Prognostic value of sex-hormone receptor expression in non-muscle-invasive bladder cancer.

Science.gov (United States)

Nam, Jong Kil; Park, Sung Woo; Lee, Sang Don; Chung, Moon Kee

2014-09-01

We investigated sex-hormone receptor expression as predicting factor of recurrence and progression in patients with non-muscle invasive bladder cancer. We retrospectively evaluated tumor specimens from patients treated for transitional cell carcinoma of the bladder at our institution between January 2006 and January 2011. Performing immunohistochemistry using a monoclonal androgen receptor antibody and monoclonal estrogen receptor-beta antibody on paraffin-embedded tissue sections, we assessed the relationship of immunohistochemistry results and prognostic factors such as recurrence and progression. A total of 169 patients with bladder cancer were evaluated in this study. Sixty-threepatients had expressed androgen receptors and 52 patients had estrogen receptor beta. On univariable analysis, androgen receptor expression was significant lower in recurrence rates (p=0.001), and estrogen receptor beta expression was significant higher in progression rates (p=0.004). On multivariable analysis, significant association was found between androgen receptor expression and lower recurrence rates (hazard ratio=0.500; 95% confidence interval, 0.294 to 0.852; p=0.011), but estrogen receptor beta expression was not significantly associated with progression rates. We concluded that the possibility of recurrence was low when the androgen receptor was expressed in the bladder cancer specimen and it could be the predicting factor of the stage, number of tumors, carcinoma in situ lesion and recurrence.

[International classification of various types of monoclonal antibodies].

Science.gov (United States)

Scheen, A J

2009-01-01

Significant advances in the development of monoclonal antibodies ("mabs") have been acknowledged during the last two decades. Successive developments led to the marketing of murine antibodies ("o-mab" first, followed by chimeric antibodies ("xi-mab"), humanised antibodies ("zu-mab") and, finally, human monoclonal antibodies ("u-mab"). In order to facilitate the distinction between the various monoclonal antibodies used in clinical practice, an international nomenclature has been proposed with the use of a specific suffix corresponding to the origine/source of "mabs" preceded by an infix referring to the medicine's target. The efforts in developing new types of monoclonal antibodies aimed at improving their pharmacokinetics (longer half-life), pharmacodynamics (better efficacy because of stronger affinity to human receptor), and safety profile (less antigenic and immunogenic reactions). These progresses could be obtained thanks to the remarkable development of molecular biotechnology.

Field flow fractionation for assessing neonatal Fc receptor and Fcγ receptor binding to monoclonal antibodies in solution.

Science.gov (United States)

Pollastrini, Joey; Dillon, Thomas M; Bondarenko, Pavel; Chou, Robert Y-T

2011-07-01

Analysis of the strength and stoichiometry of immunoglobulin G (IgG) binding to neonatal Fc receptor (FcRn) and Fcγ receptor (FcγR) is important for evaluating the pharmacokinetics and effector functions of therapeutic monoclonal antibody (mAb) products, respectively. The current standard for assessing FcγR and FcRn binding is composed of cell-based and surface plasmon resonance (SPR) assays. In this work, asymmetrical flow field flow fractionation (AF4) was evaluated to establish the true stoichiometry of IgG binding in solution. AF4 and liquid chromatography-mass spectrometry (LC-MS) were applied to directly observe IgG/FcγR and IgG/FcRn complexes, which were not observed using nonequilibrium size exclusion chromatography (SEC) analysis. Human serum albumin (HSA), an abundant component of human blood and capable of binding FcRn, was studied in combination with FcRn and IgG. AF4 demonstrated that the majority of large complexes of IgG/FcRn/HSA were at an approximate 1:2:1 molar ratio. In addition, affinity measurements of the complex were performed in the sub-micromolar affinity range. A significant decrease in binding was detected for IgG molecules with increased oxidation in the Fc region. AF4 was useful in detecting weak binding between full-length IgG/Fc fragments and Fc receptors and the effect of chemical modifications on binding. AF4 is a useful technique in the assessment of mAb product quality attributes. Copyright © 2011 Elsevier Inc. All rights reserved.

Human cerebrospinal fluid monoclonal N-methyl-D-aspartate receptor autoantibodies are sufficient for encephalitis pathogenesis.

Science.gov (United States)

Kreye, Jakob; Wenke, Nina K; Chayka, Mariya; Leubner, Jonas; Murugan, Rajagopal; Maier, Nikolaus; Jurek, Betty; Ly, Lam-Thanh; Brandl, Doreen; Rost, Benjamin R; Stumpf, Alexander; Schulz, Paulina; Radbruch, Helena; Hauser, Anja E; Pache, Florence; Meisel, Andreas; Harms, Lutz; Paul, Friedemann; Dirnagl, Ulrich; Garner, Craig; Schmitz, Dietmar; Wardemann, Hedda; Prüss, Harald

2016-10-01

SEE ZEKERIDOU AND LENNON DOI101093/AWW213 FOR A SCIENTIFIC COMMENTARY ON THIS ARTICLE: Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a recently discovered autoimmune syndrome associated with psychosis, dyskinesias, and seizures. Little is known about the cerebrospinal fluid autoantibody repertoire. Antibodies against the NR1 subunit of the NMDAR are thought to be pathogenic; however, direct proof is lacking as previous experiments could not distinguish the contribution of further anti-neuronal antibodies. Using single cell cloning of full-length immunoglobulin heavy and light chain genes, we generated a panel of recombinant monoclonal NR1 antibodies from cerebrospinal fluid memory B cells and antibody secreting cells of NMDAR encephalitis patients. Cells typically carried somatically mutated immunoglobulin genes and had undergone class-switching to immunoglobulin G, clonally expanded cells carried identical somatic hypermutation patterns. A fraction of NR1 antibodies were non-mutated, thus resembling 'naturally occurring antibodies' and indicating that tolerance induction against NMDAR was incomplete and somatic hypermutation not essential for functional antibodies. However, only a small percentage of cerebrospinal fluid-derived antibodies reacted against NR1. Instead, nearly all further antibodies bound specifically to diverse brain-expressed epitopes including neuronal surfaces, suggesting that a broad repertoire of antibody-secreting cells enrich in the central nervous system during encephalitis. Our functional data using primary hippocampal neurons indicate that human cerebrospinal fluid-derived monoclonal NR1 antibodies alone are sufficient to cause neuronal surface receptor downregulation and subsequent impairment of NMDAR-mediated currents, thus providing ultimate proof of antibody pathogenicity. The observed formation of immunological memory might be relevant for clinical relapses. © The Author (2016). Published by Oxford University Press on

Assessment of estrogen receptor-monoclonal antibody interaction by high performance liquid chromatography

International Nuclear Information System (INIS)

Brandt, D.W.; Wittliff, J.L.

1986-01-01

To define the interrelationships between the various isoforms of the estrogen receptors (ER), a monoclonal antibody-horse radish peroxidase conjugate H222 was used as a probe in conjunction with HPIEC (Synchrom AX-1000) and HPSEC (TSK-3000 SW Toyo Soda) columns. ER from breast tumors was assessed using [16α- 125 I]-iodoestradiol-17β (3nM) +/-200 fold excess estradiol-17β and excess H222. When ER was analyzed by HPSEC (size and shape), with 400 mM KCl which caused the dissociation of ER into 4S isoforms, a shift in retension time to higher molecular weight species was seen. The H222 appeared to interact with most isoforms of ER. However, when ER was analyzed by HPIEC (surface charge) with H222, a shift in virtually all of the high salt (150mM) isoform to the flow-through was observed with only 46% shift in elution of the low salt (60-70mM) isoforms. H222 did not alter total ER binding capacity. These data suggest that H222 recognized discrete forms of the ER. Therefore, modification in the receptor may have occurred which masks or removes the antigenic determinant limiting the specificity of H222. These results indicate that H222 may be employed as a tool to elucidate the interrelationships between these ER species

Effect of producer cell line on functional activity of anti-D monoclonal antibodies destined for prevention of rhesus sensitization.

Science.gov (United States)

Olovnikova, N I; Ershler, M A; Belkina, E V; Nikolaeva, T L; Miterev, G Yu

2009-04-01

The ability of anti-D antibodies to cause antigen-specific immunosuppression depends on their interaction with low-affinity Fcgamma-receptors. Human monoclonal antibodies to D antigen of the rhesus system were investigated by antibody-dependent cytotoxicity assay in order to estimate their ability to induce hemolysis mediated by low-affinity Fcgamma receptors. We demonstrate that affinity of monoclonal antibodies to receptors of this type does not depend on primary structure of Fc-fragment, but depends on the producer cell line which expresses the antibodies. Monoclonal IgG1 antibodies interacting with FcgammaRIIa and FcgammaRIII lost this property, if they were secreted by human-mouse heterohybridoma, but not by human B-cell line. On the opposite, monoclonal antibodies that could not activate low-affinity Fcgamma receptors were highly active after human cells fusion with rat myeloma YB2/0. Hemolytic activity of IgG3 remained unchanged after fusion of human cells with rodent cells.

A randomized, phase II study of the anti-insulin-like growth factor receptor type 1 (IGF-1R) monoclonal antibody robatumumab (SCH 717454) in patients with advanced colorectal cancer

International Nuclear Information System (INIS)

Lin, Edward H; Lenz, Heinz-Josef; Saleh, Mansoor N; Mackenzie, Mary J; Knost, James A; Pathiraja, Kumudu; Langdon, Ronald B; Yao, Siu-Long; Lu, Brian D

2014-01-01

Overexpression of insulin-like growth factor receptor type 1 (IGF-1R) may promote tumor development and progression in some cancer patients. Our objective was to assess tumor uptake of fluorodeoxyglucose by positron-emission tomography in patients with chemotherapy-refractory colorectal cancer treated with an anti-insulin-like growth factor receptor type 1 (anti-IGF-1R) monoclonal antibody, robatumumab. This was a randomized, open-label study with two periods (P1 and P2). Patients were randomized 3:1 into treatment arms R/R and C/R that received, respectively, one cycle of 0.3 mg/kg robatumumab or one or more cycles of second-line chemotherapy in P1, followed in either case by 10 mg/kg robatumumab biweekly in P2. The primary measure of fluorodeoxyglucose uptake was maximum standardized uptake value (SUV max ). The primary endpoint was the proportion of patients in the R/R arm having a mean percent decrease from baseline in SUV max (DiSUV) greater than 20% 12–14 days postdose in P2. Secondary endpoints included Response Evaluation Criteria in Solid Tumors (RECIST)-defined tumor response and pharmacodynamic measures of target engagement. Among 41 patients who were evaluable for the primary endpoint, seven (17%, 95% CI 7%–32%) had DiSUV greater than 20%. Fifty robatumumab-treated patients were evaluable for RECIST-defined tumor response and six (12%) had stable disease lasting greater than or equal to 7 weeks in P2. Pharmacodynamic endpoints indicated target engagement after dosing with 10 mg/kg robatumumab, but not 0.3 mg/kg. The most frequently reported adverse events were fatigue/asthenia, nausea, anorexia, and gastrointestinal disturbances. In this study, few patients with chemotherapy-refractory colorectal cancer appeared to benefit from treatment with the IGF-1R antagonist robatumumab

The strength of small: Improved targeting of Insulin-like Growth Factor-1 Receptor (IGF-1R) with F(ab')2-R1507 fragments in Ewing sarcomas

NARCIS (Netherlands)

Fleuren, Emmy D. G.; Versleijen-Jonkers, Yvonne M. H.; Heskamp, Sandra; Roeffen, Melissa H. S.; Bouwman, Wilbert H.; Molkenboer-Kuenen, Janneke D. M.; van Laarhoven, Hanneke W. M.; Oyen, Wim J. G.; Boerman, Otto C.; van der Graaf, Winette T. A.

2013-01-01

To investigate whether F(ab')2-fragments of the monoclonal Insulin-like Growth Factor-1 Receptor (IGF-1R) antibody R1507 (F(ab')2-R1507) can successfully target IGF-1R in Ewing sarcomas (ES). BALB/c nude mice were subcutaneously implanted with IGF-1R-expressing human ES xenografts (EW-5 and EW-8)

Pharmacokinetics, biodistribution and dosimetry of {sup 99m}Tc-labeled anti-human epidermal growth factor receptor humanized monoclonal antibody R3 in rats

Energy Technology Data Exchange (ETDEWEB)

Escobar, Normando Iznaga; Morales, Alejo Morales; Duconge, Jorge; Torres, Idania Caballero; Fernandez, Eduardo; Gomez, Jose A

1998-01-01

The pharmacokinetics, biodistribution and dosimetry of {sup 99m}Tc-labeled anti-human epidermal growth factor receptor (anti-hEGF-r) humanized monoclonal antibody (MAb) R3 was investigated following intravenous injection in normal Wistar rats. Serum disappearance curves were best fit by a two-compartment model having a mean distribution half-life (t{sub (1(2{alpha}}{sub ))}) of 0.250 h and a mean elimination (t{sub (1(2{beta}}{sub ))}) of 13.89 h. Among the various organs, a little accumulation of the radiolabeled antibody was found only in kidneys. Biodistribution and dosimetry studies in humans were performed by extrapolation of the animal data to humans. Absorbed dose to normal organs and the remainder of the whole body were estimated using the medical internal radiation dose formula, and dose contributions from radioactivity in transit through the gastrointestinal tract were estimated using a compartment model. Extrapolated values of radiation absorbed dose to normal organs in rads per millicurie administered were whole body, 0.0085; lower large intestine wall, 0.0898; small intestine, 0.0530; upper large intestine wall, 0.0731; and kidneys, 0.0455. The effective dose equivalent predicted was 0.0162 rem/mCi and the effective dose was found to be 0.015 rem/mCi. On the basis of the pharmacokinetics, biodistribution and internal radiation dosimetry information obtained in this study, a diagnostic phase I clinical trial with {sup 99m}Tc-labeled humanized MAb R3 conjugate in patients should be supported.

Monoclonal antibodies to human factor VII: production of immunodepleted plasma for VII:C assays.

OpenAIRE

Takase, T; Tuddenham, E G; Chand, S; Goodall, A H

1988-01-01

A high affinity monoclonal antibody to factor VII (RFF-VII/1), coupled to sepharose, was used to immunodeplete factor VII from normal plasma. The plasma could be used as a substrate in a one stage coagulation assay and performed as well as, or better than, commercially available factor VII deficient plasma or plasma from congenitally deficient factor VII patients. Plasma from normal donors (n = 20), patients with liver disease (n = 20), and patients receiving warfarin (n = 20), or congenitall...

A first‐in‐human pharmacodynamic and pharmacokinetic study of a fully human anti‐glucagon receptor monoclonal antibody in normal healthy volunteers

Science.gov (United States)

Kostic, Ana; King, Thomas Alexander; Yang, Feng; Chan, Kuo‐Chen; Yancopoulos, George D.; Gromada, Jesper

2017-01-01

Aims Glucagon receptor (GCGR) blockers are being investigated as potential therapeutics for type 1 and type 2 diabetes. Here we report the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of REGN1193, a fully human glucagon receptor blocking monoclonal antibody from a first‐in‐human healthy volunteer randomized double‐blinded trial. Methods Healthy men and women received single ascending doses of REGN1193 ranging from 0.05 to 0.6 mg/kg (n = 42) or placebo (n = 14) intravenously. Safety, tolerability and PK were assessed over 106 days. The glucose‐lowering effect of REGN1193 was assessed after induction of hyperglycaemia by serial glucagon challenges. Results REGN1193 was generally well tolerated. There were small (50 mg/dL, and did not require treatment or medical assistance. Concentration‐time profiles suggest a 2‐compartment disposition and marked nonlinearity, consistent with target‐mediated clearance. REGN1193 inhibited the glucagon‐stimulated glucose increase in a dose‐dependent manner. The 0.6 mg/kg dose inhibited the glucagon‐induced glucose area under the curve for 0 to 90 minutes (AUC0‐90 minutes) by 80% to 90% on days 3 and 15, while blunting the increase in C‐peptide. REGN1193 dose‐dependently increased total GLP‐1, GLP‐2 and glucagon, with plasma levels returning to baseline by day 29 in all dose groups. Conclusion REGN1193, a GCGR‐blocking monoclonal antibody, produced a safety, tolerability and PK/PD profile suitable for further clinical development. The occurrence of transient elevations in serum hepatic aminotransferases observed here and reported with several small molecule glucagon receptor antagonists suggests an on‐target effect of glucagon receptor blockade. The underlying mechanism is unknown. PMID:28755409

Fibroblast growth factor receptors in breast cancer.

Science.gov (United States)

Wang, Shuwei; Ding, Zhongyang

2017-05-01

Fibroblast growth factor receptors are growth factor receptor tyrosine kinases, exerting their roles in embryogenesis, tissue homeostasis, and development of breast cancer. Recent genetic studies have identified some subtypes of fibroblast growth factor receptors as strong genetic loci associated with breast cancer. In this article, we review the recent epidemiological findings and experiment results of fibroblast growth factor receptors in breast cancer. First, we summarized the structure and physiological function of fibroblast growth factor receptors in humans. Then, we discussed the common genetic variations in fibroblast growth factor receptors that affect breast cancer risk. In addition, we also introduced the potential roles of each fibroblast growth factor receptors isoform in breast cancer. Finally, we explored the potential therapeutics targeting fibroblast growth factor receptors for breast cancer. Based on the biological mechanisms of fibroblast growth factor receptors leading to the pathogenesis in breast cancer, targeting fibroblast growth factor receptors may provide new opportunities for breast cancer therapeutic strategies.

Monoclonal antibody 1.6.1 against human MPL receptor allows HSC enrichment of CB and BM CD34(+)CD38(-) populations.

Science.gov (United States)

Petit Cocault, Laurence; Fleury, Maud; Clay, Denis; Larghero, Jérôme; Vanneaux, Valérie; Souyri, Michèle

2016-04-01

Thrombopoietin (TPO) and its receptor Mpl (CD110) play a crucial role in the regulation of hematopoietic stem cells (HSCs). Functional study of Mpl-expressing HSCs has, however, been hampered by the lack of efficient monoclonal antibodies, explaining the very few data available on Mpl(+) HSCs during human embryonic development and after birth. Investigating the main monoclonal antibodies used so far to sort CD110(+) cells from cord blood (CB) and adult bone marrow (BM), we found that only the recent monoclonal antibody 1.6.1 engineered by Immunex Corporation was specific. Using in vitro functional assays, we found that this antibody can be used to sort a CD34(+)CD38(-)CD110(+) population enriched in hematopoietic progenitor stem cells, both in CB and in adult BM. In vivo injection into NSG mice further indicated that the CB CD34(+)CD38(-)CD110(+) population is highly enriched in HSCs compared with both CD34(+)CD38(-)CD110(-) and CD34(+)CD38(-) populations. Together our results validate MAb1.6.1 as an important tool, which has so far been lacking, in the HSC field. Copyright © 2016 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights reserved.

Imaging thrombus with radiolabelled monoclonal antibody to platelets

Energy Technology Data Exchange (ETDEWEB)

Peters, A.M.; Lavender, J.P.; Needham, S.G.; Loutfi, I.; Snook, D.; Epenetos, A.A.; Lumley, P.; Keery, R.J.; Hogg, N.

1986-12-13

A study was conducted evaluating a method of imaging thrombus with platelets radiolabelled with a /sup 111/In labelled monoclonal antibody, P256, directed to the platelet surface glycoprotein complex IIb/IIIa. when the number of receptors occupied by P256 was less than 3% of the total available on the platelet surface, platelet function was undisturbed. P256 was radiolabelled with /sup 111/In using diethylenetriaminepenta-acetic acid, which achieved a specific activity of 185 MBq (5 mCi)/mg. No impairment of immunoreactivity was detected at this specific activity. Platelets were labelled with radiolabelled monoclonal antibody in vitro in two patients at a receptor occupancy of 6% and in vivo in six patients at a receptor occupancy of 1%. In vivo recovery and biodistribution kinetics suggested that after in vitro labelling platelets were minimally activated. The /sup 111/In kinetics recorded after intravenous P256 suggested rapid and efficient radiolabelling of platelets and gave no indication of platelet activation. Of the six patients who received intravenous P256, three had documented thrombus, two of whom gave positive results on P256 platelet scintigraphy. The third had chronic deep venous thrombosis and was scintigraphically negative.

Monoclonal antibodies and cancer

International Nuclear Information System (INIS)

Haisma, H.J.

1987-01-01

The usefulness of radiolabeled monoclonal antibodies for imaging and treatment of human (ovarian) cancer was investigated. A review of tumor imaging with monoclonal antibodies is presented. Special attention is given to factors that influence the localization of the antibodies in tumors, isotope choice and methods of radiolabeling of the monoclonal antibodies. Two monoclonal antibodies, OC125 and OV-TL3, with high specificity for human epithelial ovarian cancer are characterized. A simple radio-iodination technique was developed for clinical application of the monoclonal antibodies. The behavior of monoclonal antibodies in human tumor xenograft systems and in man are described. Imaging of tumors is complicated because of high background levels of radioactivity in other sites than the tumor, especially in the bloodpool. A technique was developed to improve imaging of human tumor xenographs in nude mice, using subtraction of a specific and a non-specific antibody, radiolabeled with 111 In, 67 Ga and 131 I. To investigate the capability of the two monoclonal antibodies, to specifically localize in human ovarian carcinomas, distribution studies in mice bearing human ovarian carcinoma xenografts were performed. One of the antibodies, OC125, was used for distribution studies in ovarian cancer patients. OC125 was used because of availability and approval to use this antibody in patients. The same antibody was used to investigate the usefulness of radioimmunoimaging in ovarian cancer patients. The interaction of injected radiolabeled antibody OC125 with circulating antigen and an assay to measure the antibody response in ovarian cancer patients after injection of the antibody is described. 265 refs.; 30 figs.; 19 tabs

Mapping of monoclonal antibody- and receptor-binding domains on human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) using a surface plasmon resonance-based biosensor.

Science.gov (United States)

Laricchia-Robbio, L; Liedberg, B; Platou-Vikinge, T; Rovero, P; Beffy, P; Revoltella, R P

1996-10-01

An automated surface plasmon resonance (SPR)-based biosensor system has been used for mapping antibody and receptor-binding regions on the recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) molecule. A rabbit antimouse IgG1-Fc antibody (RAM.Fc) was coupled to an extended carboxymethylated-hydrogel matrix attached to a gold surface in order to capture an anti-rhGM-CSF monoclonal antibody (MAb) injected over the sensing layer. rhGM-CSF was subsequently injected and allowed to bind to this antibody. Multisite binding assays were then performed, by flowing sequentially other antibodies and peptides over the surface, and the capacity of the latter to interact with the entrapped rhGM-CSF in a multimolecular complex was monitored in real time with SPR. Eleven MAb (all IgG1K), were analyzed: respectively, four antipeptide MAb raised against three distinct epitopes of the cytokine (two clones against residues 14-24, that includes part of the first alpha-helix toward the N-terminal region; one clone against peptide 30-41, an intrahelical loop; and one clone against residues 79-91, including part of the third alpha-helix) and seven antiprotein MAbs raised against the entire rhGM-CSF, whose target native epitopes are still undetermined. In addition, the binding capacity to rhGM-CSF of a synthetic peptide, corresponding to residues 238-254 of the extracellular human GM-CSF receptor alpha-chain, endowed with rhGM-CSF binding activity, was tested. The results from experiments performed with the biosensor were compared with those obtained by a sandwich enzyme-linked immunosorbent assay (ELISA), using the same reagents. The features of the biosensor technology (fully automated, measure in real time, sharpened yes/no response, less background disturbances, no need for washing step or labeling of the reagent) offered several advantages in these studies of MAb immunoreactivity and epitope mapping, giving a much better resolution and enabling more distinct

A novel rabbit anti-hepatocyte growth factor monoclonal neutralizing antibody inhibits tumor growth in prostate cancer cells and mouse xenografts

International Nuclear Information System (INIS)

Yu, Yanlan; Chen, Yicheng; Ding, Guoqing; Wang, Mingchao; Wu, Haiyang; Xu, Liwei; Rui, Xuefang; Zhang, Zhigen

2015-01-01

The hepatocyte growth factor and its receptor c-Met are correlated with castration-resistance in prostate cancer. Although HGF has been considered as an attractive target for therapeutic antibodies, the lack of cross-reactivity of monoclonal antibodies with human/mouse HGFs is a major obstacle in preclinical developments. We generated a panel of anti-HGF RabMAbs either blocking HGF/c-Met interaction or inhibiting c-Met phosphorylation. We selected one RabMAb with mouse cross-reactivity and demonstrated that it blocked HGF-stimulated downstream activation in PC-3 and DU145 cells. Anti-HGF RabMAb inhibited not only the growth of PC-3 cells but also HGF-dependent proliferation in HUVECs. We further demonstrated the efficacy and potency of the anti-HGF RabMAb in tumor xenograft mice models. Through these in vitro and in vivo experiments, we explored a novel therapeutic antibody for advanced prostate cancer. - Highlights: • HGF is an attractive target for castration-refractory prostate cancer. • We generated and characterized a panel of anti-HGF rabbit monoclonal antibodies. • More than half of these anti-HGF RabMAbs was cross-reactive with mouse HGF. • Anti-HGF RabMAb blocks HGF-stimulated phosphorylation and cell growth in vitro. • Anti-HGF RabMAb inhibits tumor growth and angiogenesis in xenograft mice

A novel rabbit anti-hepatocyte growth factor monoclonal neutralizing antibody inhibits tumor growth in prostate cancer cells and mouse xenografts

Energy Technology Data Exchange (ETDEWEB)

Yu, Yanlan; Chen, Yicheng; Ding, Guoqing; Wang, Mingchao; Wu, Haiyang; Xu, Liwei; Rui, Xuefang; Zhang, Zhigen, E-mail: srrshurology@163.com

2015-08-14

The hepatocyte growth factor and its receptor c-Met are correlated with castration-resistance in prostate cancer. Although HGF has been considered as an attractive target for therapeutic antibodies, the lack of cross-reactivity of monoclonal antibodies with human/mouse HGFs is a major obstacle in preclinical developments. We generated a panel of anti-HGF RabMAbs either blocking HGF/c-Met interaction or inhibiting c-Met phosphorylation. We selected one RabMAb with mouse cross-reactivity and demonstrated that it blocked HGF-stimulated downstream activation in PC-3 and DU145 cells. Anti-HGF RabMAb inhibited not only the growth of PC-3 cells but also HGF-dependent proliferation in HUVECs. We further demonstrated the efficacy and potency of the anti-HGF RabMAb in tumor xenograft mice models. Through these in vitro and in vivo experiments, we explored a novel therapeutic antibody for advanced prostate cancer. - Highlights: • HGF is an attractive target for castration-refractory prostate cancer. • We generated and characterized a panel of anti-HGF rabbit monoclonal antibodies. • More than half of these anti-HGF RabMAbs was cross-reactive with mouse HGF. • Anti-HGF RabMAb blocks HGF-stimulated phosphorylation and cell growth in vitro. • Anti-HGF RabMAb inhibits tumor growth and angiogenesis in xenograft mice.

A high affinity monoclonal antibody recognizing the light chain of human coagulating factor VII.

Science.gov (United States)

Sarial, Sheila; Asadi, Farzad; Jeddi-Tehrani, Mahmood; Hadavi, Reza; Bayat, Ali Ahmad; Mahmoudian, Jafar; Taghizadeh-Jahed, Masoud; Shokri, Fazel; Rabbani, Hodjattallah

2012-12-01

Factor VII (FVII) is a serine protease-coagulating element responsible for the initiation of an extrinsic pathway of clot formation. Here we generated and characterized a high affinity monoclonal antibody that specifically recognizes human FVII. Recombinant human FVII (rh-FVII) was used for the production of a monoclonal antibody using BALB/c mice. The specificity of the antibody was determined by Western blot using plasma samples from human, mouse, sheep, goat, bovine, rabbit, and rat. Furthermore, the antibody was used to detect transiently expressed rh-FVII in BHK21 cell line using Western blot and sandwich ELISA. A mouse IgG1 (kappa chain) monoclonal antibody clone 1F1-B11 was produced against rh-FVII. The affinity constant (K(aff)) of the antibody was calculated to be 6.4×10(10) M(-1). The antibody could specifically recognize an epitope on the light chain of hFVII, with no reactivity with factor VII from several other animals. In addition, transiently expressed rh-FVII in BHK21 cells was recognized by 1F1-B11. The high affinity as well as the specificity of 1F1-B11 for hFVII will facilitate the affinity purification of hFVII and also production of FVII deficient plasma and minimizes the risk of bovine FVII contamination when fetal bovine serum-supplemented media are used for production and subsequent purification of rh-FVII.

Imaging thrombus with radiolabelled monoclonal antibody to platelets

International Nuclear Information System (INIS)

Loutfi, I.; Peters, A.M.; Lavender, J.P.; Epenetos, A.A.

1988-01-01

Indium-111-hydroxyquinoline labelled platelets, though useful in the detection of thrombus, have not gained widespread use owing to the time and technical skill required for their preparation. A study was therefore conducted evaluating a new method of imaging thrombus with platelets radiolabelled with a 111 In labelled monoclonal antibody, P 256 , directed to the platelet surface glycoprotein complex IIb/IIIa. When the number of receptors occupied by P 256 was less than 3% of the total available on the platelet surface platelet function, as assessed by platelet aggregometry, was undisturbed. P 256 was radiolabelled with 111 In using diethylenetriaminepenta-acetic acid, which achieved a specific activity of 185 MBq (5 mCi)/mg. No impairment of immunoreactivity was detected at this specific activity. Platelets were labelled with radiolabelled monoclonal antibody in vitro in two patients at a receptor occupancy of 6% and in vivo - that is, by direct intravenous injection of P 256 - in six patients at a receptor occupancy of 1%. In vivo recovery and biodistribution kinetics suggested that after in vitro labelling platelets were minimally activated. The 111 In kinetics recorded after intravenous P 256 suggested rapid and efficient radiolabelling of platelets and gave no indication of platelet activation. Of the six patients who received intravenous P 256 , three had documented thrombus, tow of whom gave positive results on P 256 platelet scintigraphy. The third subject had chromic deep venous thrombosis and was scintigraphically negative. Imaging thrombus using a radiolabelled monoclonal antibody directed to platelets appears to offer great potential as a simple, non-invasive approach to the diagnosis of thrombosis. 3 refs. (Author)

Recent Advances of Colony-Stimulating Factor-1 Receptor (CSF-1R) Kinase and Its Inhibitors.

Science.gov (United States)

El-Gamal, Mohammed I; Al-Ameen, Shahad K; Al-Koumi, Dania M; Hamad, Mawadda G; Jalal, Nouran A; Oh, Chang-Hyun

2018-01-17

Colony stimulation factor-1 receptor (CSF-1R), which is also known as FMS kinase, plays an important role in initiating inflammatory, cancer, and bone disorders when it is overstimulated by its ligand, CSF-1. Innate immunity, as well as macrophage differentiation and survival, are regulated by the stimulation of the CSF-1R. Another ligand, interlukin-34 (IL-34), was recently reported to activate the CSF-1R receptor in a different manner. The relationship between CSF-1R and microglia has been reviewed. Both CSF-1 antibodies and small molecule CSF-1R kinase inhibitors have now been tested in animal models and in humans. In this Perspective, we discuss the role of CSF-1 and IL-34 in producing cancer, bone disorders, and inflammation. We also review the newly discovered and improved small molecule kinase inhibitors and monoclonal antibodies that have shown potent activity toward CSF-1R, reported from 2012 until 2017.

Laminin binding protein, 34/67 laminin receptor, carries stage-specific embryonic antigen-4 epitope defined by monoclonal antibody Raft.2

International Nuclear Information System (INIS)

Katagiri, Yohko U.; Kiyokawa, Nobutaka; Nakamura, Kyoko; Takenouchi, Hisami; Taguchi, Tomoko; Okita, Hajime; Umezawa, Akihiro; Fujimoto, Junichiro

2005-01-01

We previously produced monoclonal antibodies against the detergent-insoluble microdomain, i.e., the raft microdomain, of the human renal cancer cell line ACHN. Raft.2, one of these monoclonal antibodies, recognizes sialosyl globopentaosylceramide, which has the stage-specific embryonic antigen (SSEA)-4 epitope. Although the mouse embryonal carcinoma (EC) cell line F9 does not express SSEA-4, some F9 cells stained with Raft.2. Western analysis and matrix-assisted laser desorption ionization-time of flight mass spectrometry identified the Raft.2 binding molecule as laminin binding protein (LBP), i.e., 34/67 laminin receptor. Weak acid treatment or digestion with Clostridium perfringens sialidase reduced Raft.2 binding to LBP on nitrocellulose sheets and [ 14 C]galactose was incorporated into LBP, indicating LBP to have a sialylated carbohydrate moiety. Subcellular localization analysis by sucrose density-gradient centrifugation and examination by confocal microscopy revealed LBP to be localized on the outer surface of the plasma membrane. An SSEA-4-positive human EC cell line, NCR-G3 cells, also expressed Raft.2-binding LBP

Characterization of the receptors for mycobacterial cord factor in Guinea pig.

Directory of Open Access Journals (Sweden)

Kenji Toyonaga

Full Text Available Guinea pig is a widely used animal for research and development of tuberculosis vaccines, since its pathological disease process is similar to that present in humans. We have previously reported that two C-type lectin receptors, Mincle (macrophage inducible C-type lectin, also called Clec4e and MCL (macrophage C-type lectin, also called Clec4d, recognize the mycobacterial cord factor, trehalose-6,6'-dimycolate (TDM. Here, we characterized the function of the guinea pig homologue of Mincle (gpMincle and MCL (gpMCL. gpMincle directly bound to TDM and transduced an activating signal through ITAM-bearing adaptor molecule, FcRγ. Whereas, gpMCL lacked C-terminus and failed to bind to TDM. mRNA expression of gpMincle was detected in the spleen, lymph nodes and peritoneal macrophages and it was strongly up-regulated upon stimulation of zymosan and TDM. The surface expression of gpMincle was detected on activated macrophages by a newly established monoclonal antibody that also possesses a blocking activity. This antibody potently suppressed TNF production in BCG-infected macrophages. Collectively, gpMincle is the TDM receptor in the guinea pig and TDM-Mincle axis is involved in host immune responses against mycobacteria.

Characterization of the receptors for mycobacterial cord factor in Guinea pig.

Science.gov (United States)

Toyonaga, Kenji; Miyake, Yasunobu; Yamasaki, Sho

2014-01-01

Guinea pig is a widely used animal for research and development of tuberculosis vaccines, since its pathological disease process is similar to that present in humans. We have previously reported that two C-type lectin receptors, Mincle (macrophage inducible C-type lectin, also called Clec4e) and MCL (macrophage C-type lectin, also called Clec4d), recognize the mycobacterial cord factor, trehalose-6,6'-dimycolate (TDM). Here, we characterized the function of the guinea pig homologue of Mincle (gpMincle) and MCL (gpMCL). gpMincle directly bound to TDM and transduced an activating signal through ITAM-bearing adaptor molecule, FcRγ. Whereas, gpMCL lacked C-terminus and failed to bind to TDM. mRNA expression of gpMincle was detected in the spleen, lymph nodes and peritoneal macrophages and it was strongly up-regulated upon stimulation of zymosan and TDM. The surface expression of gpMincle was detected on activated macrophages by a newly established monoclonal antibody that also possesses a blocking activity. This antibody potently suppressed TNF production in BCG-infected macrophages. Collectively, gpMincle is the TDM receptor in the guinea pig and TDM-Mincle axis is involved in host immune responses against mycobacteria.

Biodistribution of 99mTc-labeled anti-human epidermal growth factor receptor (EGF-R) humanized monoclonal antibody h-R3 in a xenograft model of human lung adenocarcinoma

International Nuclear Information System (INIS)

Morales-Morales, Alejo; Duconge, Jorge; Caballero-Torres, Idania; Nunez-Gandolff, Gilda; Fernandez, Eduardo; Iznaga-Escobar, Normando

1999-01-01

The anti-human epidermal growth factor receptor (EGF-R) humanized monoclonal antibody (MAb) h-R3 is an (IgG 1 ), which binds to an extracellular domain of EGF-R. It was used to evaluate the biodistribution on nude mice xenografted with H-125 human lung adenocarcinoma cell line. Results were compared with its murine version of the MAb ior-egf/r3. Twenty-one athymic female 4NMRI nu/nu mice were injected intraperitoneally with 10 μg/100 μCi of 99m Tc-labeled MAbs. Immunoreactivity of 99m Tc-labeled MAbs were measured by enzyme-linked immunosorbent assay (ELISA) on H-125 cell line and the immunoreactive fractions was determined by the Lindmo method. Among all organs, significant accumulation was found in serum (27.05 ± 2.08 %ID/g) and tumor (3.903 ± 0.89 %ID/g) at 4 h after injection. These values decreased to 5.03 ± 0.50 %ID/g and 2.19 ± 0.56 %ID/g for serum and tumor, respectively. The immunoreactive fraction was found to be 0.70, with a correlation coefficient r=0.9984. With the good biodistribution and tumor uptake of the 99m Tc-labeled humanized antibody h-R3, a phase I diagnostic clinical trial of tumor with epithelial origin should be pursued

Stepwise Progress in Epidermal Growth Factor Receptor/Radiation Studies for Head and Neck Cancer

International Nuclear Information System (INIS)

Harari, Paul M.

2007-01-01

The U.S. Food and Drug Administration approval of four new epidermal growth factor receptor (EGFR) inhibitors for cancer therapy (cetuximab, panitumumab, gefitinib, and erlotinib) over the last 3 years is a remarkable milestone in oncology. Indeed, molecular inhibition of EGFR signaling represents one of the most promising current arenas for the development of molecular-targeted cancer therapies. Epidermal growth factor receptor inhibitors from both the monoclonal antibody and tyrosine kinase inhibitor class have demonstrated clinical activity in the treatment of a broad spectrum of common human malignancies. For the discipline of radiation oncology, the 2006 report of a phase III trial demonstrating a survival advantage for advanced head and neck cancer patients with the addition of weekly cetuximab during a 7-week course of radiation is particularly gratifying. Indeed, this is the first phase III trial to confirm a survival advantage with the addition of a molecular-targeted agent to radiation. Furthermore, this result seems to have been achieved with only a modest increment in overall treatment toxicity and with very high compliance to the prescribed treatment regimen. Nevertheless, much remains to be learned regarding the rational integration of EGFR inhibitors into cancer treatment regimens, as well as methods to optimize the selection of patients most likely to benefit from EGFR inhibitor strategies

Monoclonal TCR-redirected tumor cell killing.

Science.gov (United States)

Liddy, Nathaniel; Bossi, Giovanna; Adams, Katherine J; Lissina, Anna; Mahon, Tara M; Hassan, Namir J; Gavarret, Jessie; Bianchi, Frayne C; Pumphrey, Nicholas J; Ladell, Kristin; Gostick, Emma; Sewell, Andrew K; Lissin, Nikolai M; Harwood, Naomi E; Molloy, Peter E; Li, Yi; Cameron, Brian J; Sami, Malkit; Baston, Emma E; Todorov, Penio T; Paston, Samantha J; Dennis, Rebecca E; Harper, Jane V; Dunn, Steve M; Ashfield, Rebecca; Johnson, Andy; McGrath, Yvonne; Plesa, Gabriela; June, Carl H; Kalos, Michael; Price, David A; Vuidepot, Annelise; Williams, Daniel D; Sutton, Deborah H; Jakobsen, Bent K

2012-06-01

T cell immunity can potentially eradicate malignant cells and lead to clinical remission in a minority of patients with cancer. In the majority of these individuals, however, there is a failure of the specific T cell receptor (TCR)–mediated immune recognition and activation process. Here we describe the engineering and characterization of new reagents termed immune-mobilizing monoclonal TCRs against cancer (ImmTACs). Four such ImmTACs, each comprising a distinct tumor-associated epitope-specific monoclonal TCR with picomolar affinity fused to a humanized cluster of differentiation 3 (CD3)-specific single-chain antibody fragment (scFv), effectively redirected T cells to kill cancer cells expressing extremely low surface epitope densities. Furthermore, these reagents potently suppressed tumor growth in vivo. Thus, ImmTACs overcome immune tolerance to cancer and represent a new approach to tumor immunotherapy.

Therapies based on inhibitors of the epidermal growth factor receptor: enclosing the future

International Nuclear Information System (INIS)

Diaz, Arlhee; Lage, Agustin

2007-01-01

The Epidermal Growth Factor Receptor (EGFR) is considered an important target for rational drug design due to its key role in numerous tumors. Potential contribution of EGFR-related signaling pathways to promote tumorigenic processes, including cell proliferation, angiogenesis, and resistance to apoptosis has been well established. Two classes of anti-EGFR agents in late-stage clinical testing include monoclonal antibodies against extracellular EGFR domain (Cetuximab, Nimotuzumab) and small molecules tyrosine kinase inhibitors, which inhibit the receptor enzyme activity (Gefitinib, Erlotinib). A considerable body of evidence has emerged since its introduction in the treatment of cancer patients. However, important questions such as reliable surrogate markers to predict response to the treatment, or optimal sequence and combination of these agents with conventional therapies remain to be addressed. Identify and validate predictive factors to select patients likely to respond to EGFR inhibitors, such as mutations that confer resistance versus those associated with sensitivity is required. A better understanding of molecular mechanisms associated with antitumor activity will useful to predict the interaction of these agents with other therapies in order to avoid antagonisms or overlapping effects resulting in no adding effects. Finally, the benefits derived from EGFR inhibitors as first-line therapy in selected populations, and the optimal doses and ways to delivery to the tumor site resulting in optimal target modulation should be established by the ongoing investigation. (Author)

Chimeric monoclonal antibody to tumor necrosis factor alpha (infliximab in psoriasis

Directory of Open Access Journals (Sweden)

Sridhar J

2006-01-01

Full Text Available Background: Insights into the pathogenesis of psoriasis have provided opportunities to target key steps in the disease process. Tumor necrosis factor-alpha (TNF-a being crucial to the pathogenesis of psoriasis, monoclonal antibodies against this cytokine have proved useful in its treatment. Aim: To study the efficacy of chimeric monoclonal antibody to TNF-a (infliximab in Indian patients with recalcitrant psoriasis vulgaris. Materials and Methods: Three patients with recalcitrant psoriasis vulgaris were studied. Baseline haemogram, biochemical parameters, chest radiograph and Mantoux skin test were performed. A loading dose regimen of 5 mg/kg infliximab was administered at weeks 0, 2 and 6. PASI assessment, adverse drug event monitoring and laboratory assessments were carried out at 2-week intervals until week 10. Patients were followed up until week 22 for relapse. Results: Infliximab was well tolerated. The mean PASI was 25.4 at presentation and declined to 5.5 at 10 weeks. PASI 75 was attained at a mean of 9.6 weeks. Relapse occurred at a mean of 18.6 weeks after the first infusion. Conclusions: This study on Indian patients brings out the importance of cytokine-based therapies in psoriasis. Indigenous production could make these therapies a viable therapeutic option for psoriasis patients in the near future.

Radiotherapy and receptor of epidermal growth factor

International Nuclear Information System (INIS)

Deberne, M.

2009-01-01

The expression level of the receptor of the epidermal growth factor is in correlation with the tumor cells radiosensitivity. An overexpression of the E.G.F.R. is often present in the bronchi cancer, epidermoid carcinomas of the O.R.L. sphere, esophagus, uterine cervix, and anal duct but also in the rectum cancers and glioblastomas. At the clinical level, the E.G.F.R. expression is in correlation with an unfavourable prognosis after radiotherapy in numerous tumoral localizations. In the rectum cancers it is an independent prognosis factor found in multifactorial analysis: increase of the rate of nodes and local recurrence when the E.G.F.R. is over expressed. In the uterine cervix cancers, the survival is is negatively affected in multifactorial analysis by the E.G.F.R. membranes expression level. At the therapy level, the development of anti E.G.F.R. targeted therapies (tyrosine kinase inhibitors and monoclonal antibodies) opens a new therapy field at radio-sensitivity potentiality. The irradiation makes an activation of the E.G.F.R. way that would be partially responsible of the post irradiation tumoral repopulation. This activation leads the phosphorylation of the PI3 kinase ways and M.A.P. kinase ones, then the Akt protein one that acts an apoptotic modulator part. It has been shown that blocking the E.G.F.R. way acts on three levels: accumulation of ells in phase G1, reduction of the cell repair and increasing of apoptosis. he inhibition of post irradiation action of the E.G.F.R. signal way is a factor explaining the ionizing radiation - anti E.G.F.R. synergy. The preclinical data suggest that the E.G.F.R. blocking by the monoclonal antibodies is more important than the use of tyrosine kinase inhibitors. A first positive randomized study with the cetuximab, published in 2006 in the epidermoid carcinomas of the O.R.L. sphere lead to its authorization on the market with the radiotherapy for this localization. The use of cetuximab in other indication with or in

Optimization of IGF-1R SPECT/CT Imaging Using In-111-Labeled F(ab ')(2) and Fab Fragments of Article the Monoclonal Antibody R1507

NARCIS (Netherlands)

Heskamp, Sandra; van Laarhoven, Hanneke W. M.; Molkenboer-Kuenen, Janneke D. M.; Bouwman, Wilbert H.; van der Graaf, Winette T. A.; Oyen, Wim J. G.; Boerman, Otto C.

2012-01-01

The insulin-like growth factor 1 receptor (IGF-1R) is a potential new target for the treatment of breast cancer. Patients with breast cancer lesions that express IGF-1R may benefit from treatment with anti-IGF-IR antibodies. IGF-1R expression can be visualized using radiolabeled R1507, a monoclonal

Biodistribution of {sup 99m}Tc-labeled anti-human epidermal growth factor receptor (EGF-R) humanized monoclonal antibody h-R3 in a xenograft model of human lung adenocarcinoma

Energy Technology Data Exchange (ETDEWEB)

Morales-Morales, Alejo; Duconge, Jorge; Caballero-Torres, Idania; Nunez-Gandolff, Gilda; Fernandez, Eduardo; Iznaga-Escobar, Normando E-mail: normando@ict.cim.sld.cu

1999-04-01

The anti-human epidermal growth factor receptor (EGF-R) humanized monoclonal antibody (MAb) h-R3 is an (IgG{sub 1}), which binds to an extracellular domain of EGF-R. It was used to evaluate the biodistribution on nude mice xenografted with H-125 human lung adenocarcinoma cell line. Results were compared with its murine version of the MAb ior-egf/r3. Twenty-one athymic female 4NMRI nu/nu mice were injected intraperitoneally with 10 {mu}g/100 {mu}Ci of {sup 99m}Tc-labeled MAbs. Immunoreactivity of {sup 99m}Tc-labeled MAbs were measured by enzyme-linked immunosorbent assay (ELISA) on H-125 cell line and the immunoreactive fractions was determined by the Lindmo method. Among all organs, significant accumulation was found in serum (27.05 {+-} 2.08 %ID/g) and tumor (3.903 {+-} 0.89 %ID/g) at 4 h after injection. These values decreased to 5.03 {+-} 0.50 %ID/g and 2.19 {+-} 0.56 %ID/g for serum and tumor, respectively. The immunoreactive fraction was found to be 0.70, with a correlation coefficient r=0.9984. With the good biodistribution and tumor uptake of the {sup 99m}Tc-labeled humanized antibody h-R3, a phase I diagnostic clinical trial of tumor with epithelial origin should be pursued.

Treatment with anti-interferon-δ monoclonal antibodies modifies experimental autoimmune encephalomyelitis in interferon-δ receptor knockout mice

DEFF Research Database (Denmark)

Espejo, C.; Penkowa, Milena; Saez-Torres, I.

2001-01-01

Neuroinflammation, neuronal degeneration, regeneration, monoclonal antibodies, multiple schlerosis......Neuroinflammation, neuronal degeneration, regeneration, monoclonal antibodies, multiple schlerosis...

Monoclonal antibody

International Nuclear Information System (INIS)

Oyamada, Hiyoshimaru

1987-01-01

Some aspects of monoclonal antibodies are described, centering on studies made by the author and those presented at the Second International Conference on Monoclonal Antibody Immunoconjugates for Cancer held in March this year (1987). The history of immuno-nuclear medicine and procedures for producing monoclonal antibodies are briefly outlined. Monoclonal antibodies are immunoglobulins. Here, the structure of IgG, which is used most frequently, is described. An IgG is composed of two antigen binding fragments (Fab) and one crystallizable fragment (Fc). The end portion of a Fab reacts with an antigen. One of the major applications of immuno-nuclear medicine is the diagnosis of cancer. As label nucleides, 131 I and 111 I were selected in most cases in the past while 123 I and 99m Tc are currently used more often. Advantages and disadvantages of this diagnosis method is discussed citing studies presented at the First (1986) and Second (1987) International Conference on Monoclonal Antibody Immunoconjugates for Cancer. The present status of the application of monoclonal antibodies to treatment of cancer is also described. (Nogami, K.)

Chimeric antigen receptor (CAR-specific monoclonal antibody to detect CD19-specific T cells in clinical trials.

Directory of Open Access Journals (Sweden)

Bipulendu Jena

Full Text Available Clinical trials targeting CD19 on B-cell malignancies are underway with encouraging anti-tumor responses. Most infuse T cells genetically modified to express a chimeric antigen receptor (CAR with specificity derived from the scFv region of a CD19-specific mouse monoclonal antibody (mAb, clone FMC63. We describe a novel anti-idiotype monoclonal antibody (mAb to detect CD19-specific CAR(+ T cells before and after their adoptive transfer. This mouse mAb was generated by immunizing with a cellular vaccine expressing the antigen-recognition domain of FMC63. The specificity of the mAb (clone no. 136.20.1 was confined to the scFv region of the CAR as validated by inhibiting CAR-dependent lysis of CD19(+ tumor targets. This clone can be used to detect CD19-specific CAR(+ T cells in peripheral blood mononuclear cells at a sensitivity of 1∶1,000. In clinical settings the mAb is used to inform on the immunophenotype and persistence of administered CD19-specific T cells. Thus, our CD19-specific CAR mAb (clone no. 136.20.1 will be useful to investigators implementing CD19-specific CAR(+ T cells to treat B-lineage malignancies. The methodology described to develop a CAR-specific anti-idiotypic mAb could be extended to other gene therapy trials targeting different tumor associated antigens in the context of CAR-based adoptive T-cell therapy.

Monoclonal antibodies and recombinant immunoglobulins for the treatment of multiple sclerosis.

Science.gov (United States)

Gensicke, Henrik; Leppert, David; Yaldizli, Özgür; Lindberg, Raija L P; Mehling, Matthias; Kappos, Ludwig; Kuhle, Jens

2012-01-01

Multiple sclerosis (MS) is an inflammatory and degenerative disease leading to demyelination and axonal damage in the CNS. Autoimmunity plays a central role in MS pathogenesis. Per definition, monoclonal antibodies are recombinant biological compounds with a well defined target, thus carrying the promise of targeting pathogenic cells or molecules with high specificity, avoiding undesired off-target effects. Natalizumab was the first monoclonal antibody to be approved for the treatment of MS. Several other monoclonal antibodies are in development and have demonstrated promising efficacy in phase II studies. They can be categorized according to their mode of action into compounds targeting (i) leukocyte migration into the CNS (natalizumab); (ii) cytolytic antibodies (rituximab, ocrelizumab, ofatumumab, alemtuzumab); or (iii) antibodies and recombinant proteins targeting cytokines and chemokines and their receptors (daclizumab, ustekinumab, atacicept, tabalumab [Ly-2127399], secukinumab [AIN457]). In this review, we discuss the specific molecular targets, clinical efficacy and safety of these compounds and discuss criteria to anticipate the position of monoclonal antibodies in the diversifying armamentarium of MS therapy in the coming years.

TRAIL death receptors and cancer therapeutics

International Nuclear Information System (INIS)

Huang Ying; Sheikh, M. Saeed

2007-01-01

Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) also known as Apo2L is an apoptotic molecule that belongs to the tumor necrosis factor superfamily of cytokines. It mediates its apoptotic effects via its cognate death receptors including DR4 and DR5. Agonistic monoclonal antibodies have also been developed that selectively activate TRAIL death receptors to mediate apoptosis. Multiple clinically relevant agents also upregulate the expression of TRAIL death receptors, and cooperate with TRAIL as well as DR4 and DR5-specific agonistic antibodies to exhibit tumor cell killing. TRAIL is currently in phase I clinical trials, whereas DR4 and DR5-specific agonistic antibodies have been tested in phase I and II studies. Thus, TRAIL has clearly distinguished itself from the other family members including TNF-alpha and FasL both of which could not make it to the clinic due to their toxic nature. It is therefore, evident that the future of TRAIL-based therapeutic approaches looks brighter

Urokinase-type plasminogen activator receptor (uPAR), tissue factor (TF) and epidermal growth factor receptor (EGFR)

DEFF Research Database (Denmark)

Christensen, Anders; Kiss, Katalin; Lelkaitis, Giedrius

2017-01-01

Background: Tumor-specific biomarkers are a prerequisite for the development of targeted imaging and therapy in oral squamous cell carcinoma (OSCC). urokinase-type Plasminogen Activator Receptor (uPAR), Tissue Factor (TF) and Epidermal Growth Factor Receptor (EGFR) are three biomarkers that exhib...... with a reduced survival. uPAR seems to be a prognostic biomarker in oral cancer....

A radioligand immunoassay for 1,25-dihydroxyvitamin D3 receptors using monoclonal antibody: detection of a phenotypic receptor variant in vitamin D-dependency rickets (type II) which does not bind hormone

International Nuclear Information System (INIS)

Pike, J.W.; Dokoh, Shigeharu; Liberman, U.A.; Eil, C.; Haussler, M.R.; Marx, S.J.

1984-01-01

Vitamin D-dependency rickets, type II (VDDRII), is a well recognized heritable disorder characterized by peripheral target organ resistance to 1,25-dihydroxyvitamin D 3 (1,25(OH) 2 D 3 ), the hormonally active form of the vitamin. Recently, cultured skin fibroblasts obtained from a number of patients with VDDRII have been utilized to characterize the underlying molecular defects associated with this malady. Recently monoclonal antibodies to the vitamin D receptor have been generated, and a radioligand immunoassay (RLIA) for the detection of this molecule has been developed which is independent of its hormone-binding capacity. This report describes the application of the immunoassay in the detection of receptor-like molecules in fibroblasts derived from patients with VDDRII. The results indicate that the molecule is generally present in all patients, and provides a mechanism for individual responsiveness to pharmacologic treatment with vitamin D 3 metabolites. 8 refs.; 3 figs.; 1 table

Mixed Lichenoid and Follicular T- and B-Cell Lymphoid Reaction to Red Tattoos With Monoclonal T Cells.

Science.gov (United States)

Zaaroura, Hiba; Bergman, Reuven

2017-09-28

Pseudolymphomatous reactions have been described to occur in tattoos. Most cases have exhibited T-cell predominance and polyclonal T-cell receptor gene rearrangements. One case with monoclonal IgH gene rearrangements progressed into B-cell lymphoma. Lichenoid infiltrates are commonly described but lymphoid follicles much less frequently. We report a case with mixed lichenoid and follicular T- and B-cell reaction to red tattoos. The histopathology and the immunohistochemical studies were constant with a mixed T- and B-cell pseudolymphoma, the IgH gene rearrangement study was polyclonal, but the T-cell receptor gene rearrangement study was monoclonal. The patient who responded to intralesional corticosteroid injections remains under close scrutiny.

Molecular and Therapeutic Characterization of Anti-ectodysplasin A Receptor (EDAR) Agonist Monoclonal Antibodies*

Science.gov (United States)

Kowalczyk, Christine; Dunkel, Nathalie; Willen, Laure; Casal, Margret L.; Mauldin, Elizabeth A.; Gaide, Olivier; Tardivel, Aubry; Badic, Giovanna; Etter, Anne-Lise; Favre, Manuel; Jefferson, Douglas M.; Headon, Denis J.; Demotz, Stéphane; Schneider, Pascal

2011-01-01

The TNF family ligand ectodysplasin A (EDA) and its receptor EDAR are required for proper development of skin appendages such as hair, teeth, and eccrine sweat glands. Loss of function mutations in the Eda gene cause X-linked hypohidrotic ectodermal dysplasia (XLHED), a condition that can be ameliorated in mice and dogs by timely administration of recombinant EDA. In this study, several agonist anti-EDAR monoclonal antibodies were generated that cross-react with the extracellular domains of human, dog, rat, mouse, and chicken EDAR. Their half-life in adult mice was about 11 days. They induced tail hair and sweat gland formation when administered to newborn EDA-deficient Tabby mice, with an EC50 of 0.1 to 0.7 mg/kg. Divalency was necessary and sufficient for this therapeutic activity. Only some antibodies were also agonists in an in vitro surrogate activity assay based on the activation of the apoptotic Fas pathway. Activity in this assay correlated with small dissociation constants. When administered in utero in mice or at birth in dogs, agonist antibodies reverted several ectodermal dysplasia features, including tooth morphology. These antibodies are therefore predicted to efficiently trigger EDAR signaling in many vertebrate species and will be particularly suited for long term treatments. PMID:21730053

Recurrent exposure to nicotine differentiates human bronchial epithelial cells via epidermal growth factor receptor activation

International Nuclear Information System (INIS)

Martinez-Garcia, Eva; Irigoyen, Marta; Anso, Elena; Martinez-Irujo, Juan Jose; Rouzaut, Ana

2008-01-01

Cigarette smoking is the major preventable cause of lung cancer in developed countries. Nicotine (3-(1-methyl-2-pyrrolidinyl)-pyridine) is one of the major alkaloids present in tobacco. Besides its addictive properties, its effects have been described in panoply of cell types. In fact, recent studies have shown that nicotine behaves as a tumor promoter in transformed epithelial cells. This research focuses on the effects of acute repetitive nicotine exposure on normal human bronchial epithelial cells (NHBE cells). Here we show that treatment of NHBE cells with recurrent doses of nicotine up to 500 μM triggered cell differentiation towards a neuronal-like phenotype: cells emitted filopodia and expressed neuronal markers such as neuronal cell adhesion molecule, neurofilament-M and the transcription factors neuronal N and Pax-3. We also demonstrate that nicotine treatment induced NF-kB translocation to the nucleus, phosphorylation of the epidermal growth factor receptor (EGFR), and accumulation of heparin binding-EGF in the extracellular medium. Moreover, addition of AG1478, an inhibitor of EGFR tyrosine phosphorylation, or cetuximab, a monoclonal antibody that precludes ligand binding to the same receptor, prevented cell differentiation by nicotine. Lastly, we show that differentiated cells increased their adhesion to the extracellular matrix and their protease activity. Given that several lung pathologies are strongly related to tobacco consumption, these results may help to better understand the damaging consequences of nicotine exposure

Chimeric opioid peptides: Tools for identifying opioid receptor types

International Nuclear Information System (INIS)

Xie, G.; Miyajima, A.; Yokota, T.; Arai, K.; Goldstein, A.

1990-01-01

The authors synthesized several chimeric [125J-labelled] peptides in which the N-terminal nine residues of dynorphin-32, a peptide selective for the κ opioid receptor, were replaced by opioid peptides selective for other opioid receptor types. Each chimeric peptide retained the high affinity and type selectivity characteristic of its N-terminal sequence. The common C-terminal two-thirds of the chimeric peptides served as an epitope recognized by the same monoclonal antibody. When bound to receptors on a cell surface or membrane preparation, these peptides could still bind specifically to the monoclonal antibody. These chimeric peptides should be useful for isolating μ, δ, and κ opioid receptors and for identifying opioid receptors on transfected cells in expression cloning procedures. The general approach using chimeric peptides should be applicable to other peptide receptors

Monoclonal antibodies for treating cancer

International Nuclear Information System (INIS)

Dillman, R.O.

1989-01-01

The purpose of this study is to assess the current status of in-vivo use of monoclonal antibodies for treating cancer. Publications appearing between 1980 and 1988 were identified by computer searches using MEDLINE and CANCERLIT, by reviewing the table of contents of recently published journals, and by searching bibliographies of identified books and articles. More than 700 articles, including peer-reviewed articles and book chapters, were identified and selected for analysis. The literature was reviewed and 235 articles were selected as relevant and representative of the current issues and future applications for in-vivo monoclonal antibodies for cancer therapy and of the toxicity and efficacy which has been associated with clinical trials. Approaches include using antibody alone (interacting with complement or effector cells or binding directly with certain cell receptors) and immunoconjugates (antibody coupled to radioisotopes, drugs, toxins, or other biologicals). Most experience has been with murine antibodies. Trials of antibody alone and radiolabeled antibodies have confirmed the feasibility of this approach and the in-vivo trafficking of antibodies to tumor cells. However, tumor cell heterogeneity, lack of cytotoxicity, and the development of human antimouse antibodies have limited clinical efficacy. Although the immunoconjugates are very promising, heterogeneity and the antimouse immune response have hampered this approach as has the additional challenge of chemically or genetically coupling antibody to cytotoxic agents. As a therapeutic modality, monoclonal antibodies are still promising but their general use will be delayed for several years. New approaches using human antibodies and reducing the human antiglobulin response should facilitate treatment. 235 references

Selectivity verification of cardiac troponin monoclonal antibodies for cardiac troponin detection by using conventional ELISA

Science.gov (United States)

Fathil, M. F. M.; Arshad, M. K. Md; Gopinath, Subash C. B.; Adzhri, R.; Ruslinda, A. R.; Hashim, U.

2017-03-01

This paper presents preparation and characterization of conventional enzyme-linked immunosorbent assay (ELISA) for cardiac troponin detection to determine the selectivity of the cardiac troponin monoclonal antibodies. Monoclonal antibodies, used to capture and bind the targets in this experiment, are cTnI monoclonal antibody (MAb-cTnI) and cTnT monoclonal antibody (MAb-cTnT), while both cardiac troponin I (cTnI) and T (cTnT) are used as targets. ELISA is performed inside two microtiter plates for MAb-cTnI and MAb-cTnT. For each plate, monoclonal antibodies are tested by various concentrations of cTnI and cTnT ranging from 0-6400 µg/l. The binding selectivity and level of detection between monoclonal antibodies and antigen are determined through visual observation based on the color change inside each well on the plate. ELISA reader is further used to quantitatively measured the optical density of the color changes, thus produced more accurate reading. The results from this experiment are utilized to justify the use of these monoclonal antibodies as bio-receptors for cardiac troponin detection by using field-effect transistor (FET)-based biosensors coupled with substrate-gate in the future.

Effects of vitamin D(3)-binding protein-derived macrophage activating factor (GcMAF) on angiogenesis.

Science.gov (United States)

Kanda, Shigeru; Mochizuki, Yasushi; Miyata, Yasuyoshi; Kanetake, Hiroshi; Yamamoto, Nobuto

2002-09-04

The vitamin D(3)-binding protein (Gc protein)-derived macrophage activating factor (GcMAF) activates tumoricidal macrophages against a variety of cancers indiscriminately. We investigated whether GcMAF also acts as an antiangiogenic factor on endothelial cells. The effects of GcMAF on angiogenic growth factor-induced cell proliferation, chemotaxis, and tube formation were examined in vitro by using cultured endothelial cells (murine IBE cells, porcine PAE cells, and human umbilical vein endothelial cells [HUVECs]) and in vivo by using a mouse cornea micropocket assay. Blocking monoclonal antibodies to CD36, a receptor for the antiangiogenic factor thrombospondin-1, which is also a possible receptor for GcMAF, were used to investigate the mechanism of GcMAF action. GcMAF inhibited the endothelial cell proliferation, chemotaxis, and tube formation that were all stimulated by fibroblast growth factor-2 (FGF-2), vascular endothelial growth factor-A, or angiopoietin 2. FGF-2-induced neovascularization in murine cornea was also inhibited by GcMAF. Monoclonal antibodies against murine and human CD36 receptor blocked the antiangiogenic action of GcMAF on the angiogenic factor stimulation of endothelial cell chemotaxis. In addition to its ability to activate tumoricidal macrophages, GcMAF has direct antiangiogenic effects on endothelial cells independent of tissue origin. The antiangiogenic effects of GcMAF may be mediated through the CD36 receptor.

Clinical application of antibody monoclonal humanized anti-EGFrnimotuzumab labeled

International Nuclear Information System (INIS)

Perera Pintado, Alejandro; Peña Quián, Yamilé; Batista Cuéllar, Juan F.; Prats Capote, Anaís; Torres Aroche, Leonel A.; Casacó Santana, Caridad; Sánchez Mendosa, Elvia L.; Sánchez González, Yolaine; Romero Collado, Susana; Quesada Pozo, Rodobaldo; Valladares Oviedo, Lourdes; Masquida García, Elsa M.; Leyva Montaña, René; Casacó, Angel; Ramos Suzarte, Mayra; Crombet, Tania

2016-01-01

Most malignant tumors are of epithelial origin. These are characterized by overexpression of the receptor of epidermal growth factor (EGFR), which the neoplastic cells escape the regulatory mechanisms are allowed, so its high concentration of membrane is generally associated with a poor prognosis . By binding an antibody specifically to this receptor, preventing binding of EGF latter and activation mechanism tyrosine kinase inhibiting cell mitosis and apoptosis causing tumor cell. For this reason, the EGFr has been considered as an attractive target for anti-tumor therapy. The humanized monoclonal antibody anti-EGFr nimotuzumab was developed by the Center of Molecular Immunology (Havana, Cuba). Numerous clinical trials have been developed in the Department of Clinical Research Center Isotopes (Cuba), in which it has been applied this antibody, both labeled with 99mTc for immuno gammagraphic detection of tumors, as labeled with 188 Re for radioimmunotherapy of gliomas high degree of malignancy. The aim of this paper is to show the experience of the Department of Clinical Research of CENTIS in various clinical trials with marking for both immuno gammagraphics detection of tumors, such as for radioimmunotherapy nimotuzumab. (author)

Radioimmunoscintigraphy with monoclonal antibody Technetium-99m-Anti-EGF-Receptor (R3-MAB) for the detection of head and neck tumours, metastasis and recurrence. Final report for the period 15 April 1995 - 15 April 1997

International Nuclear Information System (INIS)

Oliva Gonzalez, J.P.

1998-03-01

A clinical study was carried out to determine the sensitivity of radioimmunoscintigraphy (RIS) using indigenously produced mouse monoclonal antibody (MAB) against epidermal growth factor receptor in the detection of primary, recurrent and metastatic malignant epithelial tumours of the head and neck region in 13 patients. The MAB was labelled with 99m Tc and imaging was carried out using gamma camera and SPECT. The results were correlated with histopathological findings. RIS gave a sensitivity of 76.9%. This study showed that the indigenously produced MAB can be used for the detection of malignant epithelial tumours in the head and neck region but the MAB will be further characterized to improve its sensitivity in the detection of the neoplasia. (author)

Elucidation of the critical epitope of an anti-EGFR monoclonal antibody EMab-134.

Science.gov (United States)

Kaneko, Mika K; Yamada, Shinji; Itai, Shunsuke; Chang, Yao-Wen; Nakamura, Takuro; Yanaka, Miyuki; Kato, Yukinari

2018-07-01

The epidermal growth factor receptor (EGFR) is a type-1 transmembrane receptor tyrosine kinase, which activates the downstream signaling cascades in many tumors, such as oral and lung cancers. We previously developed EMab-134, a novel anti-EGFR monoclonal antibody (mAb), which reacts with endogenous EGFR-expressing cancer cell lines and normal cells independent of glycosylation in Western blotting, flow cytometry, and immunohistochemical analysis. EMab-134 showed very high sensitivity (94.7%) to oral squamous cell carcinomas in immunohistochemical analysis. In this study, we performed enzyme-linked immunosorbent assay (ELISA), flow cytometry, and immunohistochemical analysis to determine the epitope of EMab-134. A blocking peptide (375-394 amino acids of EGFR) neutralized the EMab-134 reaction against oral cancer cells in flow cytometry and immunohistochemistry. The minimum epitope of EMab-134 was found to be the 377- RGDSFTHTPP -386 sequence. Our findings can be applied for the production of more functional anti-EGFR mAbs that in turn can be used for antitumor treatments.

Investigating the Interaction between the Neonatal Fc Receptor and Monoclonal Antibody Variants by Hydrogen/Deuterium Exchange Mass Spectrometry

DEFF Research Database (Denmark)

Jensen, Pernille Foged; Larraillet, Vincent; Schlothauer, Tilman

2015-01-01

The recycling of immunoglobulins by the neonatal Fc receptor (FcRn) is of crucial importance in the maintenance of antibody levels in plasma and is responsible for the long half-lives of endogenous and recombinant monoclonal antibodies. From a therapeutic point of view there is great interest...... in understanding and modulating the IgG-FcRn interaction to optimize antibody pharmacokinetics and ultimately improve efficacy and safety. Here we studied the interaction between a full-length human IgG1 and human FcRn via hydrogen/deuterium exchange mass spectrometry and targeted electron transfer dissociation...... to map sites perturbed by binding on both partners of the IgG-FcRn complex. Several regions in the antibody Fc region and the FcRn were protected from exchange upon complex formation, in good agreement with previous crystallographic studies of FcRn in complex with the Fc fragment. Interestingly, we found...

Investigation of a panel of monoclonal antibodies and polyclonal sera against anthrax toxins resulted in identification of an anti-lethal factor antibody with disease-enhancing characteristics.

Science.gov (United States)

Kulshreshtha, Parul; Tiwari, Ashutosh; Priyanka; Joon, Shikha; Sinha, Subrata; Bhatnagar, Rakesh

2015-12-01

Hybridomas were created using spleen of mice that were actively immunized with rLFn (recombinant N-terminal domain of lethal factor). Later on, separate group of mice were immunized with rLFn to obtain a polyclonal control for passive immunization studies of monoclonal antibodies. This led to the identification of one cohort of rLFn-immnized mice that harboured disease-enhancing polyclonal antibodies. At the same time, the monoclonal antibodies secreted by all the hybridomas were being tested. Two hybridomas secreted monoclonal antibodies (H10 and H8) that were cross-reactive with EF (edema factor) and LF (lethal factor), while the other two hybridomas secreted LF-specific antibodies (H7 and H11). Single chain variable fragment (LETscFv) was derived from H10 hybridoma. H11 was found to have disease-enhancing property. Combination of H11 with protective monoclonal antibodies (H8 and H10) reduced its disease enhancing nature. This in vitro abrogation of disease-enhancement provides the proof of concept that in polyclonal sera the disease enhancing character of a fraction of antibodies is overshadowed by the protective nature of the rest of the antibodies generated on active immunization. Copyright © 2015. Published by Elsevier Ltd.

Negative feedback regulation of human platelets via autocrine activation of the platelet-derived growth factor alpha-receptor.

Science.gov (United States)

Vassbotn, F S; Havnen, O K; Heldin, C H; Holmsen, H

1994-05-13

Human platelets contain platelet-derived growth factor (PDGF) in their alpha-granules which is released during platelet exocytosis. We show by immunoprecipitation and 125I-PDGF binding experiments that human platelets have functionally active PDGF alpha-receptors, but not beta-receptors. The PDGF alpha-receptor (PDGFR-alpha) was identified as a 170-kDa glycosylated protein-tyrosine kinase as found in other cell types. Stimulation of platelets with 0.1 unit/ml thrombin resulted in a significant increase (2-5-fold) of the tyrosine phosphorylation of the PDGFR-alpha, as determined by immunoprecipitation with phosphotyrosine antiserum as well as with PDGFR-alpha antiserum. The observed thrombin-induced autophosphorylation of the PDGFR-alpha was inhibited by the addition of a neutralizing monoclonal PDGF antibody. Thus, our results suggest that the platelet PDGFR-alpha is stimulated in an autocrine manner by PDGF secreted during platelet activation. Preincubation of platelets with PDGF inhibited thrombin-induced platelet aggregation and secretion of ATP + ADP and beta-hexosaminidase. Thrombin-induced platelet aggregation was also reversed when PDGF was added 30 s after thrombin stimulation. Inhibition of the autocrine PDGF pathway during platelet activation by the PDGF antibody led to a potentiation of thrombin-induced beta-hexosaminidase secretion. Thus, the PDGFR-alpha takes part in a negative feedback regulation during platelet activation. Our demonstration of PDGF alpha-receptors on human platelets and its inhibitory function during platelet activation identifies a new possible role of PDGF in the regulation of thrombosis.

Nuclear oncology with monoclonal antibodies and peptides

International Nuclear Information System (INIS)

Hosono, Makoto

1998-01-01

Imaging and therapy using radiolabeled monoclonal antibodies have proved useful in many clinical studies. However, immunogenicity of mouse antibodies to human and insufficient tumor-to-normal tissue ratios remained to be solved. Chimerization and humanization by genetic engineering, and multistep targeting techniques have enabled lower immunogenicity and higher tumor-to-normal tissue contrast. Peptides like somatostatin-analogs have been reportedly useful in imaging tumors, which are either somatostatin receptor positive or negative. Elevated normal tissue accumulation of radiolabeled peptides is a drawback in aiming internal radiation therapy. (author). 51 refs

B lymphocyte depletion with the monoclonal antibody rituximab in Graves' disease: a controlled pilot study

DEFF Research Database (Denmark)

El Fassi, Daniel; Nielsen, Claus H; Bonnema, Steen J

2007-01-01

Graves' disease (GD) is a common TSH receptor autoantibody (TRAb)-mediated disorder. Because B lymphocytes are important self-antigen presenting cells and precursors for antibody-secreting plasma cells, temporary B-lymphocyte depletion with the monoclonal antibody rituximab (RTX) might...

Enavatuzumab, a Humanized Anti-TWEAK Receptor Monoclonal Antibody, Exerts Antitumor Activity through Attracting and Activating Innate Immune Effector Cells

Directory of Open Access Journals (Sweden)

Shiming Ye

2017-01-01

Full Text Available Enavatuzumab is a humanized IgG1 anti-TWEAK receptor monoclonal antibody that was evaluated in a phase I clinical study for the treatment of solid malignancies. The current study was to determine whether and how myeloid effector cells were involved in postulated mechanisms for its potent antitumor activity in xenograft models. The initial evidence for a role of effector cells was obtained in a subset of tumor xenograft mouse models whose response to enavatuzumab relied on the binding of Fc of the antibody to Fcγ receptor. The involvement of effector cells was further confirmed by immunohistochemistry, which revealed strong infiltration of CD45+ effector cells into tumor xenografts in responding models, but minimal infiltration in nonresponders. Consistent with the xenograft studies, human effector cells preferentially migrated toward in vivo-responsive tumor cells treated by enavatuzumab in vitro, with the majority of migratory cells being monocytes. Conditioned media from enavatuzumab-treated tumor cells contained elevated levels of chemokines, which might be responsible for enavatuzumab-triggered effector cell migration. These preclinical studies demonstrate that enavatuzumab can exert its potent antitumor activity by actively recruiting and activating myeloid effectors to kill tumor cells. Enavatuzumab-induced chemokines warrant further evaluation in clinical studies as potential biomarkers for such activity.

Variability of in vivo recovery of factor IX after infusion of monoclonal antibody purified factor IX concentrates in patients with hemophilia B. The Mononine Study Group.

Science.gov (United States)

White, G C; Shapiro, A D; Kurczynski, E M; Kim, H C; Bergman, G E

1995-05-01

Monoclonal antibody purified factor IX concentrate, Mononine (Armour Pharmaceutical Company, Kankakee, Illinois, USA), is a recently developed replacement factor concentrate for the treatment of patients with hemophilia B. The pharmacokinetic properties of monoclonal antibody purified factor IX concentrate (MAb Factor IX concentrate) have been evaluated in only small samples of patients, and little is known about those factors that might influenced in vivo recovery of factor IX after infusion is a larger patient population. In vivo recovery of factor IX was therefore evaluated for 80 different indications in 72 patients who received MAb Factor IX concentrate for the management of spontaneous or trauma-induced bleeding, or as prophylaxis with surgery. The average recovery after infusions for presurgical pharmacokinetic analysis (mean +/- standard deviation) was 1.28 +/- 0.56 U/dl rise per U/kg infused (range 0.41-2.80), and the average recovery after all infusions for treatment was 1.23 +/- 0.49 U/dl rise per U/kg infused (range - 0.35-2.92). Recovery values for multiple MAb Factor IX doses in a given patient were also variable; the average recovery was 1.22 +/- 0.53 U/dl rise per U/kg given, and standard deviations ranged from 0.03 to 1.26. Patient age, weight, and MAb Factor IX concentrate dose minimally but significantly influenced factor IX recovery. There was no significant effect of either race, history of previous thrombotic complications during treatment with other replacement factor concentrates, or bleeding state on recovery. All of the patients treated with this preparation experienced excellent hemostasis, and no thrombotic complications were observed.

Novel Drosophila receptor that binds multiple growth factors

International Nuclear Information System (INIS)

Rosner, M.R.; Thompson, K.L.; Garcia, V.; Decker, S.J.

1986-01-01

The authors have recently reported the identification of a novel growth factor receptor from Drosophila cell cultures that has dual binding specificity for both insulin and epidermal growth factor (EGF). This 100 kDa protein is also antigenically related to the cytoplasmic region of the mammalian EGF receptor-tyrosine kinase. They now report that this protein binds to mammalian nerve growth factor and human transforming growth factor alpha as well as insulin and EGF with apparent dissociation constants ranging from 10 -6 to 10 -8 M. The 100 kDa protein can be affinity-labeled with these 125 I-labeled growth factors after immunoprecipitation with anti-EGF receptor antiserum. These four growth factors appear to share a common binding site, as evidenced by their ability to block affinity labelling by 125 I-insulin. No significant binding to the 100 kDa protein was observed with platelet-derived growth factor, transforming growth factor beta, or glucagon. The 100 kDa Drosophila protein has a unique ligand-binding spectrum with no direct counterpart in mammalian cells and may represent an evolutionary precursor of the mammalian receptors for these growth factors

Targeting the epidermal growth factor receptor in solid tumor malignancies

DEFF Research Database (Denmark)

Nedergaard, Mette K; Hedegaard, Chris J; Poulsen, Hans S

2012-01-01

been proposed as valid targets in many cancer therapy settings. Different strategies have been developed in order to either inhibit EGFR/EGFRvIII activity or to ablate EGFR/EGFRvIII-positive tumor cells. Drugs that inhibit these receptors include monoclonal antibodies (mAbs) that bind...... to the extracellular part of EGFR, blocking the binding sites for the EGFR ligands, and intracellular tyrosine kinase inhibitors (TKIs) that block the ATP binding site of the tyrosine kinase domain. Besides an EGFRvIII-targeted vaccine, conjugated anti-EGFR mAbs have been used in different settings to deliver lethal...... agents to the EGFR/EGFRvIII-positive cells; among these are radio-labelled mAbs and immunotoxins. This article reviews the current status and efficacy of EGFR/EGFRvIII-targeted therapies....

Nuclear medicine: Monoclonal antibodies

International Nuclear Information System (INIS)

Endo, K.; Sakahara, H.; Koizumi, M.; Kawamura, Y.; Torizuka, K.; Yokoyama, A.

1986-01-01

Antitumor monoclonal antibody was successfully labeled with Tc-99m by using dithiosemicarbazone (DTS) as a bifunctional chelating agent. In the first step, DTS was coupled to antibody without loss of immunoreactivity; the compound then efficiently formed a neutral 1:1 chelate with pentavalent or tetravalent Tc-99m. Imaging with Tc-99m-labeled monoclonal antibody to human osteosarcoma (OST-7) clearly displayed a small tumor in nude mice at 6 and 24 hours after intravenous administration. The tumor-to-blood ratio of the Tc-99m-labeled monoclonal antibody was higher than that of a radioiodinated antibody and similar to that of an In-111-labeled antibody. Thus, conjugation of DTS to monoclonal antibody followed by radiometalation is a simple and efficient method of preparing Tc-99m-labeled monoclonal antibody

Tc-99m direct radiolabeling of monoclonal antibody ior egf/r3: quality control and image studies in mice

International Nuclear Information System (INIS)

Dias, Carla Roberta; Marczewski, Barbara; Moraes, Vanessa; Barboza, Marycel Figols de; Osso Junior, Joao Alberto

2005-01-01

Monoclonal antibodies (Mabs) have been useful for immunoscintigraphic applications in clinical diagnosis since they were introduced in the practice of nuclear medicine. The ior egf/r3 (Centis, Cuba) is a murine monoclonal antibody against epidermal growth factor receptor (EGF-R) and has been widely used in the radioimmunodiagnosis of tumors of epithelial origin. Labeled with 99m Tc, its main application in Nuclear Medicine is the follow up, detection and evaluation of tumor recurrences. The objective of this work is to describe the preparation of a lyophilized formulation (kit) for radiolabeling the Mab ior egf/r3 with 99m Tc for immunoscintigraphic applications. Radiolabeling efficiency, effects on immunoreactivity, image studies and stability of the formulation are reported. The study demonstrated that the kit formulation can be labeled with 99m Tc at high yields and can be used to visualize in vivo human tumors of epithelial origin by immunoscintigraphy studies.(author)

Pharmacokinetics and concentration-effect relationships of therapeutic monoclonal antibodies and fusion proteins.

Science.gov (United States)

Ternant, David; Paintaud, Gilles

2005-09-01

Although monoclonal antibodies (mAbs) constitute a major advance in therapeutics, their pharmacokinetic (PK) and pharmacodynamic (PD) properties are not fully understood. Saturable mechanisms are thought to occur in distribution and elimination of mAbs, which are protected from degradation by the Brambell's receptor (FcRn). The binding of mAbs to their target antigen explains part of their nonlinear PK and PD properties. The interindividual variability in mAb PK can be explained by several factors, including immune response against the biodrug and differences in the number of antigenic sites. The concentration-effect relationships of mAbs are complex and dependent on their mechanism of action. Interindividual differences in mAb PD can be explained by factors such as genetics and clinical status. PK and concentration-effect studies are necessary to design optimal dosing regimens. Because of their above-mentioned characteristics, the interindividual variability in their dose-response relationships must be studied by PK-PD modelling.

Generation and characterization of tabalumab, a human monoclonal antibody that neutralizes both soluble and membrane-bound B-cell activating factor

Directory of Open Access Journals (Sweden)

Manetta J

2014-08-01

Full Text Available Joseph Manetta, Holly Bina, Paul Ryan, Niles Fox, Derrick R Witcher, Kristine Kikly Biotechnology Discovery Research, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN, USA Abstract: B-cell activating factor (BAFF is a B-cell survival factor with a key role in B-cell homeostasis and tolerance. Dysregulated BAFF expression may contribute to autoimmune diseases or B-cell malignancies via effects on abnormal B-lymphocyte activation, proliferation, survival, and immunoglobulin secretion. Monoclonal antibodies were generated against human BAFF, characterized for species specificity and affinity, and screened for the ability to neutralize both membrane-bound and soluble BAFF. In addition, studies were undertaken to determine the relative potency of membrane-bound and soluble BAFF. Tabalumab has a high affinity for human, cynomolgus monkey, and rabbit BAFF. No binding to mouse BAFF was detected. Tabalumab was able to neutralize soluble human, cynomolgus monkey, or rabbit BAFF with equal potency. Our data demonstrate that membrane-bound BAFF can be a more potent stimulus for B-cells than soluble BAFF, and tabalumab also neutralized membrane-bound BAFF. Tabalumab prevented BAFF from binding to BAFF receptors and demonstrated pharmacodynamic effects in human BAFF transgenic mice. Tabalumab is a high-affinity human antibody with neutralizing activity against membrane-bound and soluble BAFF. Given our findings that membrane-bound BAFF can have greater in vitro potency than soluble BAFF, neutralization of both forms of BAFF is likely to be important for optimal therapeutic effect. Keywords: autoimmunity, B-cell malignancies, B-cell survival factor, BAFF

Elucidation of the critical epitope of an anti-EGFR monoclonal antibody EMab-134

Directory of Open Access Journals (Sweden)

Mika K. Kaneko

2018-07-01

Full Text Available The epidermal growth factor receptor (EGFR is a type-1 transmembrane receptor tyrosine kinase, which activates the downstream signaling cascades in many tumors, such as oral and lung cancers. We previously developed EMab-134, a novel anti-EGFR monoclonal antibody (mAb, which reacts with endogenous EGFR-expressing cancer cell lines and normal cells independent of glycosylation in Western blotting, flow cytometry, and immunohistochemical analysis. EMab-134 showed very high sensitivity (94.7% to oral squamous cell carcinomas in immunohistochemical analysis. In this study, we performed enzyme-linked immunosorbent assay (ELISA, flow cytometry, and immunohistochemical analysis to determine the epitope of EMab-134. A blocking peptide (375–394 amino acids of EGFR neutralized the EMab-134 reaction against oral cancer cells in flow cytometry and immunohistochemistry. The minimum epitope of EMab-134 was found to be the 377-RGDSFTHTPP−386 sequence. Our findings can be applied for the production of more functional anti-EGFR mAbs that in turn can be used for antitumor treatments.

Tumor necrosis factor blockers influence macrophage responses to Mycobacterium tuberculosis

OpenAIRE

HARRIS, JAMES; HARRIS, JAMES

2008-01-01

PUBLISHED umor necrosis factor (TNF)?? is a proinflammatory cytokine that mediates inflammation in response to various pathogens, including Mycobacterium tuberculosis, but is also a key factor in the pathogenesis of rheumatoid arthritis and other autoimmune diseases. Three TNF???suppressing drugs have been approved to treat selected autoimmune diseases; 2 are monoclonal antibodies against TNF?? (adalimumab and infliximab), and the other is a soluble TNF receptor/Fc fusion protein (etanerce...

Comparison of (/sup 125/I)beta-endorphin binding to rat brain and NG108-15 cells using a monoclonal antibody directed against the opioid receptor

Energy Technology Data Exchange (ETDEWEB)

Bidlack, J.M.; O' Malley, W.E.; Schulz, R.

1988-02-01

The properties of (/sup 125/I)beta h-endorphin-binding sites from rat brain membranes and membranes from the NG108-15 cell line were compared using a monoclonal antibody directed against the opioid receptor and opioid peptides as probes. The binding of (/sup 125/I)beta h-endorphin to both rat brain and NG108-15 membranes yielded linear Scatchard plots with Kd values of 1.2 nM and 1.5 nM, respectively, and Bmax values of 865 fmol/mg rat brain membrane protein and 1077 fmol/mg NG108-15 membrane protein. A monoclonal antibody, OR-689.2.4, capable of inhibiting mu and delta binding but not kappa binding to rat brain membranes, noncompetitively inhibited the binding of 1 nM (/sup 125/I)beta h-endorphin to rat brain and NG108-15 membranes with an IC50 value of 405 nM for rat brain membranes and 543 nM for NG108-15 membranes. The monoclonal antibody also inhibited the binding of 3 nM (/sup 3/H) (D-penicillamine2, D-penicillamine5) enkephalin to NG108-15 membranes with an IC50 value of 370 nM. In addition to blocking the binding of (/sup 125/I)beta h-endorphin to brain membranes, the antibody also displaced (/sup 125/I)beta h-endorphin from membranes. Site-specific opioid peptides had large variations in their IC50 values depending on whether they were inhibiting (/sup 125/I)beta h-endorphin binding to rat brain or the NG108-15 membranes. When the peptides were tested with the monoclonal antibody for their combined ability to inhibit (/sup 125/I)beta h-endorphin binding to both membrane preparations, the peptides and antibody blocked binding as though they were acting at allosterically coupled sites, not two totally independent sites. These studies suggest that mu-, delta-, and beta-endorphin-binding sites share some sequence homology with the 35,000-dalton protein that the antibody is directed against.

Tc-{sup 99m} direct radiolabeling of monoclonal antibody ior egf/r3: quality control and image studies in mice

Energy Technology Data Exchange (ETDEWEB)

Dias, Carla Roberta; Marczewski, Barbara; Moraes, Vanessa; Barboza, Marycel Figols de; Osso Junior, Joao Alberto [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), SP (Brazil). Centro de Radiofarmacia]. E-mail: crdias@ipen.br

2005-10-15

Monoclonal antibodies (Mabs) have been useful for immunoscintigraphic applications in clinical diagnosis since they were introduced in the practice of nuclear medicine. The ior egf/r3 (Centis, Cuba) is a murine monoclonal antibody against epidermal growth factor receptor (EGF-R) and has been widely used in the radioimmunodiagnosis of tumors of epithelial origin. Labeled with 99m Tc, its main application in Nuclear Medicine is the follow up, detection and evaluation of tumor recurrences. The objective of this work is to describe the preparation of a lyophilized formulation (kit) for radiolabeling the Mab ior egf/r3 with 99m Tc for immunoscintigraphic applications. Radiolabeling efficiency, effects on immunoreactivity, image studies and stability of the formulation are reported. The study demonstrated that the kit formulation can be labeled with 99m Tc at high yields and can be used to visualize in vivo human tumors of epithelial origin by immunoscintigraphy studies.(author)

Brain metastasis in human epidermal growth factor receptor 2-positive breast cancer: from biology to treatment

Energy Technology Data Exchange (ETDEWEB)

Koo, Tae Ryool [Dept. of Radiation Oncology, Hallym University Chuncheon Sacred Heart Hospital, Chuncheon (Korea, Republic of); Kim, In Ah [Dept. of Radiation Oncology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of)

2016-03-15

Overexpression of human epidermal growth factor receptor 2 (HER2) is found in about 20% of breast cancer patients. With treatment using trastuzumab, an anti-HER2 monoclonal antibody, systemic control is improved. Nonetheless, the incidence of brain metastasis does not be improved, rather seems to be increased in HER2-positive breast cancer. The mainstay treatment for brain metastases is radiotherapy. According to the number of metastatic lesions and performance status of patients, radiosurgery or whole brain radiotherapy can be performed. The concurrent use of a radiosensitizer further improves intracranial control. Due to its large molecular weight, trastuzumab has a limited ability to cross the blood-brain barrier. However, small tyrosine kinase inhibitors such as lapatinib, has been noted to be a promising agent that can be used as a radiosensitizer to affect HER2-positive breast cancer. This review will outline general management of brain metastases and will focus on preclinical findings regarding the radiosensitizing effect of small molecule HER2 targeting agents.

Overexpression of c-erbB2 is a negative prognostic factor in anaplastic astrocytomas

Directory of Open Access Journals (Sweden)

Gulati Michel

2010-03-01

Full Text Available Abstract The epidermal growth factor receptor (EGFR family, consisting of four tyrosine kinase receptors, c-erbB1-4, seems to be influential in gliomagenesis. The aim of this study was to investigate EGFR gene amplification and expression of c-erbB1-4 receptor proteins in human anaplastic astrocytomas. Formalin-fixed and paraffin-embedded sections from 31 cases were investigated by standard immunohistochemical procedures for expression of c-erbB1-4 receptor proteins using commercial antibodies. EGFR gene amplification was studied by fluorescence in situ hybridization using paraffin-embedded tissues. Two monoclonal antibodies, NCL-EGFR-384 and NCL-EGFR, were used for EGFR detection and they displayed positive immunoreactivity in 97% and 71%, respectively. For c-erbB2 detection three monoclonal antibodies, CB11, 3B5, and 5A2, were applied and they displayed positive immunoreactivity in 45%, 100%, and 52%, respectively. Positive immunostaining for c-erbB3 and c-erbB4 was encountered in 97% and 74%, respectively. The EGFR gene was amplified in 9 out of 31 tumors (29%. After adjusting for age, Karnofsky performance status, and extent of surgical resection, Cox multiple regression analysis with overall survival as the dependent variable revealed that c-erbB2 overexpression detected by the monoclonal antibody clone CB11 was a statistically significant poor prognostic factor (P = 0.004. This study shows the convenience and feasibility of immunohistochemistry when determining the expression of receptor proteins in tissue sections of human astrocytomas. The synchronous overexpression of c-erbB1-4 proteins in anaplastic astrocytomas supports their role in the pathogenesis of these tumors. Further, c-erbB2 overexpression seems to predict aggressive behaviour.

Interaction of epidermal growth factor receptors with the cytoskeleton is related to receptor clustering

NARCIS (Netherlands)

van Belzen, N.; Spaargaren, M.; Verkleij, A. J.; Boonstra, J.

1990-01-01

Recently it has been established that cytoskeleton-associated epidermal growth factor (EGF) receptors are predominantly of the high-affinity class and that EGF induces a recruitment of low-affinity receptors to the cytoskeleton. The nature of this EGF-induced receptor-cytoskeleton interaction,

Radiotherapy and receptor of epidermal growth factor; Radiotherapie et recepteur de l'Epidermal Growth Factor

Energy Technology Data Exchange (ETDEWEB)

Deberne, M. [Institut Gustave-Roussy, 94 - Villejuif (France)

2009-10-15

The expression level of the receptor of the epidermal growth factor is in correlation with the tumor cells radiosensitivity. An overexpression of the E.G.F.R. is often present in the bronchi cancer, epidermoid carcinomas of the O.R.L. sphere, esophagus, uterine cervix, and anal duct but also in the rectum cancers and glioblastomas. At the clinical level, the E.G.F.R. expression is in correlation with an unfavourable prognosis after radiotherapy in numerous tumoral localizations. In the rectum cancers it is an independent prognosis factor found in multifactorial analysis: increase of the rate of nodes and local recurrence when the E.G.F.R. is over expressed. In the uterine cervix cancers, the survival is is negatively affected in multifactorial analysis by the E.G.F.R. membranes expression level. At the therapy level, the development of anti E.G.F.R. targeted therapies (tyrosine kinase inhibitors and monoclonal antibodies) opens a new therapy field at radio-sensitivity potentiality. The irradiation makes an activation of the E.G.F.R. way that would be partially responsible of the post irradiation tumoral repopulation. This activation leads the phosphorylation of the PI3 kinase ways and M.A.P. kinase ones, then the Akt protein one that acts an apoptotic modulator part. It has been shown that blocking the E.G.F.R. way acts on three levels: accumulation of ells in phase G1, reduction of the cell repair and increasing of apoptosis. he inhibition of post irradiation action of the E.G.F.R. signal way is a factor explaining the ionizing radiation - anti E.G.F.R. synergy. The preclinical data suggest that the E.G.F.R. blocking by the monoclonal antibodies is more important than the use of tyrosine kinase inhibitors. A first positive randomized study with the cetuximab, published in 2006 in the epidermoid carcinomas of the O.R.L. sphere lead to its authorization on the market with the radiotherapy for this localization. The use of cetuximab in other indication with or in

Phase 1 dose-escalation study of the antiplacental growth factor monoclonal antibody RO5323441 combined with bevacizumab in patients with recurrent glioblastoma

DEFF Research Database (Denmark)

Lassen, Ulrik; Chinot, Olivier L; McBain, Catherine

2015-01-01

BACKGROUND: We conducted a phase 1 dose-escalation study of RO5323441, a novel antiplacental growth factor (PlGF) monoclonal antibody, to establish the recommended dose for use with bevacizumab and to investigate the pharmacokinetics, pharmacodynamics, safety/tolerability, and preliminary clinica...

Monoclonal Antibodies to the Thyrotropin Receptor

Directory of Open Access Journals (Sweden)

Takao Ando

2005-01-01

Full Text Available The thyrotropin receptor (TSHR is a seven transmembrane G-protein linked glycoprotein expressed on the thyroid cell surface and which, under the regulation of TSH, controls the production and secretion of thyroid hormone from the thyroid gland. This membrane protein is also a major target antigen in the autoimmune thyroid diseases. In Graves' disease, autoantibodies to the TSHR (TSHR-Abs stimulate the TSHR to produce thyroid hormone excessively. In autoimmune thyroid failure, some patients exhibit TSHR-Abs which block TSH action on the receptor. There have been many attempts to generate human stimulating TSHR-mAbs, but to date, only one pathologically relevant human stimulating TSHR-mAb has been isolated. Most mAbs to the TSHR have been derived from rodents immunized with TSHR antigen from bacteria or insect cells. These antigens lacked the native conformation of the TSHR and the resulting mAbs were exclusively blocking or neutral TSHR-mAbs. However, mAbs raised against intact native TSHR antigen have included stimulating mAbs. One such stimulating mAb has demonstrated a number of differences in its regulation of TSHR post-translational processing. These differences are likely to be reflective of TSHR-Abs seen in Graves' disease.

The main immunogenic region of acetylcholine receptors does not provoke the formation of antibodies of a predominant idiotype.

Science.gov (United States)

Killen, J A; Hochschwender, S M; Lindstrom, J M

1985-08-01

Anti-idiotype antibodies were induced in rats by immunization with rat monoclonal antibodies to the main immunogenic region of acetylcholine receptors. These anti-idiotype antibodies showed very little crossreaction with other rat monoclonal antibodies which bind to the same region of the receptor. When the rats producing these anti-idiotype antibodies were immunized with receptor, they showed no net decrease in anti-receptor antibody production. These data indicate that, although more than half of the antibodies produced by rats immunized with receptor are directed at a small region, many anti-receptor idiotypes are involved in this response and anti-idiotype therapy is not beneficial.

Characterization and expression of the human T cell receptor-T3 complex by monoclonal antibody F101.01

DEFF Research Database (Denmark)

Geisler, C; Plesner, T; Pallesen, G

1988-01-01

A murine monoclonal antibody (MoAb) F101.01 reacting with the T cell receptor (TCR)-T3 complex is presented. Immunohistological studies showed that F101.01 specifically stains T-zone lymphocytes in lymph nodes, tonsils, and splenic tissue. Two-colour immunofluorescence and flow cytometry...... demonstrated co-expression of the antigen defined by F101.01 and the pan-T cell antigens defined by CD2, CD3, CD5, and CD7 antibodies. Cells stained with CD4 and CD8 antibodies were both included in the F101.01-positive population, whereas CD16-positive natural killer cells (NK), B cells (CD19 and CD20......), and myeloid cells (CD13 and CD33) were excluded. The target antigen of F101.01 co-modulated with the CD3-defined antigen (T3) and the TCR recognized by the MoAb WT-31. CD3 antibody and WT-31 both blocked binding of F101.01. F101.01 precipitated the TCR-T3 complex from lysates of 125I-labelled peripheral blood...

Assembly and activation of neurotrophic factor receptor complexes.

Science.gov (United States)

Simi, Anastasia; Ibáñez, Carlos F

2010-04-01

Neurotrophic factors play important roles in the development and function of both neuronal and glial elements of the central and peripheral nervous systems. Their functional diversity is in part based on their ability to interact with alternative complexes of receptor molecules. This review focuses on our current understanding of the mechanisms that govern the assembly and activation of neurotrophic factor receptor complexes. The realization that many, if not the majority, of these complexes exist in a preassembled form at the plasma membrane has forced the revision of classical ligand-mediated oligomerization models, and led to the discovery of novel mechanisms of receptor activation and generation of signaling diversity which are likely to be shared by many different classes of receptors.

Monoclonal antibody to the type I insulin-like growth factor (IGF-I) receptor blocks IGF-I receptor-mediated DNA synthesis: clarification of the mitogenic mechanisms of IGF-I and insulin in human skin fibroblasts

International Nuclear Information System (INIS)

Flier, J.S.; Usher, P.; Moses, A.C.

1986-01-01

Insulin and insulin-like growth factor type I (IGF-I) stimulate an overlapping spectrum of biological responses in human skin fibroblasts. Although insulin and IGF-I are known to stimulate the incorporation of [ 3 H]thymidine into DNA in these cells, the identify of the receptor(s) that mediates this effect has not been fully clarified. The mouse anti-human IGF-I receptor antibody αIR-3 binds with specificity to IGF-I but not to insulin receptors in human placental membranes; it also specifically inhibits the binding of 125 I-labeled IGF-I but not 125 I-labeled insulin to suspensions of human skin fibroblasts in a dose-dependent manner. αIR-3 competitively inhibits IGF-I-mediated stimulation of [ 3 H]thymidine incorporation into DNA. This inhibition is dependent on the concentration of αIR-3 and in the presence of a fixed antibody concentration can be partially overcome by high concentrations of IGF-I. In contrast, at concentrations of 3 H]thymidine incorporation is not inhibited by αIR-3. However, the incremental effects of higher concentrations (> 1 μg/ml) of insulin on [ 3 H]thymidine incorporation are inhibited by αIR-3. αIR-3 is a highly specific antagonist of IGF-I receptor-mediated mitogenesis in human skin fibroblasts. By using this antibody, it is shown directly that insulin can act through the IGF-I receptor to stimulate DNA synthesis but can also activate this effect through the insulin receptor itself

Use of AN Eosinophil Specific Monoclonal Antibody in Assessing Eosinophil Function.

Science.gov (United States)

Minkoff, Marjorie Sue

A monoclonal antibody to an eosinophil specific determinant is very important in assessing eosinophil function during helminthic infection. Eosinophils induced by Schistosoma mansoni infection in BALB/c mice were used to induce C57B1/6 immunocytes for production of hybridomas secreting eosinophil monoclonal antibodies. These antibodies were shown to react with an eosinophil surface epitope but not with neutrophils or macrophages as determined by ELISA, immunodiffusion, immunofluorescence, and immunoblot assay. Affinity chromatography with eosinophil chemotactic factor-sepharose consistently selected out a { rm M_ R} 67,000 protein from solubilized eosinophil membrane antigens but not from neutrophil and macrophage antigens. In vitro studies showed that the eosinophil-specific monoclonal antibodies abrogated antibody-dependent eosinophil -mediated killing of S. mansoni schistosomula using mouse, rat or human eosinophils. Neutrophil and macrophage killing activities were unaffected. The monoclonal antibodies effected complement-dependent lysis of mouse and rat eosinophils but not of human eosinophils. ECF-treated eosinophils showed enhanced killing of schistosomula which was blocked by the monoclonal antibody. Murine and human eosinophils preincubated with monoclonal antibody exhibited decreased chemotaxis to ECF at optimal chemotactic concentrations. The monoclonal antibody also blocked eosinophil binding to ECF- sepharose beads. In vivo induction of peripheral blood eosinophilia by injection of S. mansoni eggs was suppressed by injections of monoclonal antibodies 2CD13 and 2QD45 in mouse and rat experimental models. Eosinophilia induced by keyhole limpet hemocyanin- cyclophosphamide treatment was also suppressed by monoclonal antibody in both murine and rat systems. Pulmonary granulomas in mice given egg injection and monoclonal antibody were smaller and contained fewer eosinophils than those granulomas from mice given eggs only. In immuno-biochemical studies, the

Mouse monoclonal antibodies against human c-Mpl and characterization for flow cytometry applications.

Science.gov (United States)

Abbott, Christina; Huang, Guo; Ellison, Aaron R; Chen, Ching; Arora, Taruna; Szilvassy, Stephen J; Wei, Ping

2010-04-01

Mouse monoclonal antibodies (MAbs) against human c-Mpl, the cognate receptor for thrombopoietin (TPO), were generated using hybridoma technology and characterized by various assays to demonstrate their specificity and affinity. Two such MAbs, 1.6 and 1.75, were determined to be superior for flow cytometry studies and exhibited double-digit picomolar (pM) affinities to soluble human c-Mpl protein. Both MAbs specifically bound to cells engineered to overexpress human c-Mpl protein, immortalized human hematopoietic cell lines that express endogenous c-Mpl, primary human bone marrow and peripheral blood-derived CD34(+) cells, and purified human platelets. No binding was detected on cell lines that did not express c-Mpl. Receptor competition and siRNA knock-down studies further confirmed the specificity of antibodies 1.6 and 1.75 for human c-Mpl. In contrast to these newly generated MAbs, none of eight commercially available anti-c-Mpl antibodies tested were found to bind specifically to human c-Mpl and were thus shown to be unsuitable for flow cytometry studies. Monoclonal antibodies 1.6 and 1.75 will therefore be useful flow cytometry reagents to detect cell surface c-Mpl expression.

Human epidermal growth factor receptor 2/neu overexpression in urothelial carcinoma of the bladder and its prognostic significance: Is it worth hype?

Directory of Open Access Journals (Sweden)

Santosh Kumar

2015-01-01

Full Text Available Aims: In urothelial tumors of the urinary bladder, human epidermal growth factor receptor 2 (HER-2/neu expression has been reported over 10 years, but there is no clear correlation between prognosis and recurrence rate. The present study evaluates prognostic implication of HER-2/neu expression. Subjects and Methods: In this study, 100 formalin-fixed paraffin-embedded specimens of primary transitional cell carcinoma of the bladder were processed. HER-2/neu monoclonal antibody immunohistochemistry staining procedure used for the study. Results: A total of 70 (70% patients were positive for overexpression of HER-2/neu. HER-2/neu was positive in patients with 42 (70% superficial tumor, 28 (70% muscle invasive tumor, 41 (75.9% high-grade tumor, 29 (63% low grade tumor, 31 (68.9% recurrent tumor, and 6 (66.6% had positive lymph nodes. Conclusions: Human epidermal growth factor receptor 2/neu over expression was not correlated with the tumor stage, lymphnode metastasis or recurrence of the disease. HER-2/neu overexpression was statistically insignificantly correlated with the differentiation grade (P < 0.161 as compared to previous studies. Future studies on HER-2 expression with chemo-sensitivity and efficacy of HER-2-targeted therapies in urothelial carcinomas is needed.

Ligand Activation of TAM Family Receptors-Implications for Tumor Biology and Therapeutic Response.

Science.gov (United States)

Davra, Viralkumar; Kimani, Stanley G; Calianese, David; Birge, Raymond B

2016-11-29

The TAM family of receptors (i.e., Tyro3, Axl, and Mertk), and their ligands Growth arrest specific factor 6 (Gas6) and Protein S (Pros1) contribute to several oncogenic processes, such as cell survival, invasion, migration, chemo-resistance, and metastasis, whereby expression often correlates with poor clinical outcomes. In recent years, there has been great interest in the study of TAM receptors in cancer, stemming both from their roles as oncogenic signaling receptors, as well as their roles in tumor immunology. As a result, several classes of TAM inhibitors that include small molecule tyrosine kinase inhibitors, monoclonal antibodies, decoy receptors, as well as novel strategies to target TAM ligands are being developed. This paper will review the biology of TAM receptors and their ligands with a focus on cancer, as well as evidence-based data for the continued pursuit of TAM/Gas6 inhibitors in clinical practice.

Uses of monoclonal antibody 8H9

Science.gov (United States)

Cheung, Nai-Kong V.

2013-04-09

This invention provides a composition comprising an effective amount of monoclonal antibody 8H9 or a derivative thereof and a suitable carrier. This invention provides a pharmaceutical composition comprising an effective amount of monoclonal antibody 8H9 or a derivative thereof and a pharmaceutically acceptable carrier. This invention also provides an antibody other than the monoclonal antibody 8H9 comprising the complementary determining regions of monoclonal antibody 8H9 or a derivative thereof, capable of binding to the same antigen as the monoclonal antibody 8H9. This invention provides a substance capable of competitively inhibiting the binding of monoclonal antibody 8H9. This invention also provides an isolated scFv of monoclonal antibody 8H9 or a derivative thereof. This invention also provides the 8H9 antigen. This invention also provides different uses of the monoclonal antibody 8H9 or its derivative.

Arctigenin induced gallbladder cancer senescence through modulating epidermal growth factor receptor pathway.

Science.gov (United States)

Zhang, Mingdi; Cai, Shizhong; Zuo, Bin; Gong, Wei; Tang, Zhaohui; Zhou, Di; Weng, Mingzhe; Qin, Yiyu; Wang, Shouhua; Liu, Jun; Ma, Fei; Quan, Zhiwei

2017-05-01

Gallbladder cancer has poor prognosis and limited therapeutic options. Arctigenin, a representative dibenzylbutyrolactone lignan, occurs in a variety of plants. However, the molecular mechanisms involved in the antitumor effect of arctigenin on gallbladder cancer have not been fully elucidated. The expression levels of epidermal growth factor receptor were examined in 100 matched pairs of gallbladder cancer tissues. A positive correlation between high epidermal growth factor receptor expression levels and poor prognosis was observed in gallbladder cancer tissues. Pharmacological inhibition or inhibition via RNA interference of epidermal growth factor receptor induced cellular senescence in gallbladder cancer cells. The antitumor effect of arctigenin on gallbladder cancer cells was primarily achieved by inducing cellular senescence. In gallbladder cancer cells treated with arctigenin, the expression level of epidermal growth factor receptor significantly decreased. The analysis of the activity of the kinases downstream of epidermal growth factor receptor revealed that the RAF-MEK-ERK signaling pathway was significantly inhibited. Furthermore, the cellular senescence induced by arctigenin could be reverted by pcDNA-epidermal growth factor receptor. Arctigenin also potently inhibited the growth of tumor xenografts, which was accompanied by the downregulation of epidermal growth factor receptor and induction of senescence. This study demonstrates arctigenin could induce cellular senescence in gallbladder cancer through the modulation of epidermal growth factor receptor pathway. These data identify epidermal growth factor receptor as a key regulator in arctigenin-induced gallbladder cancer senescence.

Retrieval of estradiol receptor in paraffin sections of resting porcine uteri by microwave treatment. Immunostaining patterns obtained with different primary antibodies.

Science.gov (United States)

Sierralta, W D; Thole, H H

1996-05-01

The unmasking of estradiol receptor in paraffin sections of Bouin's-fixed uterine tissue from ovariectomized gilts was attained with microwave treatment. Immunocytochemistry of the receptor was performed using a polyclonal or five monoclonal antibodies, two of which are commercially available, reacting with different domains of the protein and an amplified-peroxidase system for detection. With five of the antibodies, a predominance of nuclear staining was observed in cells of endometrial glands, while one monoclonal antibody (13H2), reacting with the receptor's domain E, showed a preference for the cytoplasmic receptor. In stroma, all antibodies detected more receptor in nuclei than in cytoplasm. In epithelium, the commercially available antibody H222, our monoclonals 13H2 and HT65, and the polyclonal antibody 402 demonstrated more receptor in cytoplasmic than in nuclear areas. In myometrium, the nuclei from longitudinal and ring muscles were definitely stained with the antibodies. We conclude that the accessibilities of the antibody epitopes of the receptor differ according to the functional uterine cell type.

Human corpus luteum: presence of epidermal growth factor receptors and binding characteristics

International Nuclear Information System (INIS)

Ayyagari, R.R.; Khan-Dawood, F.S.

1987-01-01

Epidermal growth factor receptors are present in many reproductive tissues but have not been demonstrated in the human corpus luteum. To determine the presence of epidermal growth factor receptors and its binding characteristics, we carried out studies on the plasma cell membrane fraction of seven human corpora lutea (days 16 to 25) of the menstrual cycle. Specific epidermal growth factor receptors were present in human corpus luteum. Insulin, nerve growth factor, and human chorionic gonadotropin did not competitively displace epidermal growth factor binding. The optimal conditions for corpus luteum-epidermal growth factor receptor binding were found to be incubation for 2 hours at 4 degrees C with 500 micrograms plasma membrane protein and 140 femtomol 125 I-epidermal growth factor per incubate. The number (mean +/- SEM) of epidermal growth factor binding sites was 12.34 +/- 2.99 X 10(-19) mol/micrograms protein; the dissociation constant was 2.26 +/- 0.56 X 10(-9) mol/L; the association constant was 0.59 +/- 0.12 X 10(9) L/mol. In two regressing corpora lutea obtained on days 2 and 3 of the menstrual cycle, there was no detectable specific epidermal growth factor receptor binding activity. Similarly no epidermal growth factor receptor binding activity could be detected in ovarian stromal tissue. Our findings demonstrate that specific receptors for epidermal growth factor are present in the human corpus luteum. The physiologic significance of epidermal growth factor receptors in human corpus luteum is unknown, but epidermal growth factor may be involved in intragonadal regulation of luteal function

Monoclonal Antibodies Against Fusicoccin with Binding Characteristics Similar to the Putative Fusicoccin Receptor of Higher Plants 1

Science.gov (United States)

Feyerabend, Martin; Weiler, Elmar W.

1987-01-01

Monoclonal antibodies were raised against fusicoccin. The toxin, linked to bovine serum albumin through its t-pentenyl moiety, served as immunogen. Hybridomas secreting anti-fusicoccin antibodies were screened by radioimmunoassay employing a novel radioactive derivative, [3H]-nor-fusicoccin-alcohol of high specific activity (1.5 × 1014Bq/mole). The two monoclonal antibodies reported here are of high apparent affinity for fusicoccin (0.71 × 10−9 molar and 1.85 × 10−9 molar). This is comparable to the apparent affinity of rabbit antiserum raised against the same type of conjugate (9.3 × 10−9 molar). A method for the single step purification of the monoclonal antibodies from ascites fluid is reported. A solid-phase immunoassay, using alkaline phosphatase as enzyme, exhibits a measuring range from 0.1 to 1.5 picomoles (about 70 picograms to 1 nanogram) of fusicoccin. The displacement of [3H]-nor-fusicoccin-alcohol from the antibodies by compounds structurally related to fusicoccin exhibits similar selectivity as a microsomal binding assay with the same tracer as radiolabeled probe. Images Fig. 2 PMID:16665786

Prognosis in monoclonal proteinaemia

NARCIS (Netherlands)

Schaar, Cornelis Gerardus

2006-01-01

Monoclonal proteinaemia (M-proteinemia) is associated with multiple myeloma (MM) or other hematological malignancies. In the absence of these diseases the term MGUS (Monoclonal Gammopathy of Undetermined Significance) is used. During 1991-1993 1464 patients with newly diagnosed M-proteinemia in the

Uses of monoclonal antibody 8H9

Energy Technology Data Exchange (ETDEWEB)

Cheung, Nai-Kong V.

2018-04-10

This invention provides a composition comprising an effective amount of monoclonal antibody 8H9 or a derivative thereof and a suitable carrier. This invention provides a pharmaceutical composition comprising an effective amount of monoclonal antibody 8H9 or a derivative thereof and a pharmaceutically acceptable carrier. This invention also provides an antibody other than the monoclonal antibody 8H9 comprising the complementary determining regions of monoclonal antibody 8H9 or a derivative thereof, capable of binding to the same antigen as the monoclonal antibody 8H9. This invention provides a substance capable of competitively inhibiting the binding of monoclonal antibody 8H9. This invention also provides an isolated scFv of monoclonal antibody 8H9 or a derivative thereof. This invention also provides the 8H9 antigen. This invention also provides a method of inhibiting the growth of tumor cells comprising contacting said tumor cells with an appropriate amount of monoclonal antibody 8H9 or a derivative thereof.

MOR103, a human monoclonal antibody to granulocyte–macrophage colony-stimulating factor, in the treatment of patients with moderate rheumatoid arthritis

DEFF Research Database (Denmark)

Behrens, Frank; Tak, Paul P; Ostergaard, Mikkel

2015-01-01

OBJECTIVES: To determine the safety, tolerability and signs of efficacy of MOR103, a human monoclonal antibody to granulocyte-macrophage colony-stimulating factor (GM-CSF), in patients with rheumatoid arthritis (RA). METHODS: Patients with active, moderate RA were enrolled in a randomised...... placebo and MOR103 0.3, 1.0 and 1.5 mg/kg, respectively). Treatment emergent adverse events (AEs) in the MOR103 groups were mild or moderate in intensity and generally reported at frequencies similar to those in the placebo group. The most common AE was nasopharyngitis. In two cases, AEs were classified...... with active RA. The data support further investigation of this monoclonal antibody to GM-CSF in RA patients and potentially in those with other immune-mediated inflammatory diseases. TRIAL REGISTRATION NUMBER: NCT01023256....

Steroid hormone and epidermal growth factor receptors in meningiomas.

Science.gov (United States)

Horsfall, D J; Goldsmith, K G; Ricciardelli, C; Skinner, J M; Tilley, W D; Marshall, V R

1989-11-01

A prospective study of steroid hormone and epidermal growth factor receptor expression in 57 meningiomas is presented. Scatchard analysis of radioligand binding identified 20% of meningiomas as expressing classical oestrogen receptors (ER) at levels below that normally accepted for positivity, the remainder being negative. ER could not be visualized in any meningioma using immunocytochemistry. Alternatively, 74% of meningiomas demonstrated the presence of progesterone receptors (PR) by Scatchard analysis, the specificity of which could not be attributed to glucocorticoid or androgen receptors. Confirmation of classical PR presence was determined by immunocytochemical staining. The presence of epidermal growth factor receptor (EGFR) was demonstrated in 100% of meningiomas using immunocytochemical staining. These data are reviewed in the context of previously reported results and are discussed in relation to the potential for medical therapy as an adjunct to surgery.

Visualization of cholinoceptive neurons in the rat neocortex : colocalization of muscarinic and nicotinic acetylcholine receptors

NARCIS (Netherlands)

Zee, E.A. van der; Streefland, C.; Strosberg, A.D.; Schröder, H.; Luiten, P.G.M.

The present investigation analyzes the cellular distribution of muscarinic and nicotinic acetylcholine receptors in rat neocortex, by use of monoclonal antibodies raised against purified receptor proteins. The degree of colocalization of both types of receptors was determined by way of

Pattern of hormone receptors and human epidermal growth factor ...

African Journals Online (AJOL)

Introduction: Breast cancer is the most common cancer among women globally. With immunohistochemistry (IHC), breast cancer is classified into four groups based on IHC profile of estrogen receptor (ER)/progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2/neu) expression, positive (+) and/or ...

Predominant antitumor effects by fully human anti-TRAIL-receptor2 (DR5) monoclonal antibodies in human glioma cells in vitro and in vivo

Science.gov (United States)

Nagane, Motoo; Shimizu, Saki; Mori, Eiji; Kataoka, Shiro; Shiokawa, Yoshiaki

2010-01-01

Tumor necrosis factor–related apoptosis-inducing ligand (TRAIL/Apo2 L) preferentially induces apoptosis in human tumor cells through its cognate death receptors DR4 or DR5, thereby being investigated as a potential agent for cancer therapy. Here, we applied fully human anti-human TRAIL receptor monoclonal antibodies (mAbs) to specifically target one of death receptors for TRAIL in human glioma cells, which could also reduce potential TRAIL-induced toxicity in humans. Twelve human glioma cell lines treated with several fully human anti-human TRAIL receptor mAbs were sensitive to only anti-DR5 mAbs, whereas they were totally insensitive to anti-DR4 mAb. Treatment with anti-DR5 mAbs exerted rapid cytotoxicity and lead to apoptosis induction. The cellular sensitivity was closely associated with cell-surface expression of DR5. Expression of c-FLIPL, Akt, and Cyclin D1 significantly correlated with sensitivity to anti-DR5 mAbs. Primary cultures of glioma cells were also relatively resistant to anti-DR5 mAbs, exhibiting both lower DR5 and higher c-FLIPL expression. Downregulation of c-FLIPL expression resulted in the sensitization of human glioma cells to anti-DR5 mAbs, whereas overexpression of c-FLIPL conferred resistance to anti-DR5 mAb. Treatment of tumor-burden nude mice with the direct agonist anti-DR5 mAb KMTR2 significantly suppressed growth of subcutaneous glioma xenografts leading to complete regression. Similarly, treatment of nude mice bearing intracerebral glioma xenografts with KMTR2 significantly elongated lifespan without tumor recurrence. These results suggest that DR5 is the predominant TRAIL receptor mediating apoptotic signals in human glioma cells, and sensitivity to anti-DR5 mAbs was determined at least in part by the expression level of c-FLIPL and Akt. Specific targeting of death receptor pathway through DR5 using fully human mAbs might provide a novel therapeutic strategy for intractable malignant gliomas. PMID:20511188

Binding-site analysis of opioid receptors using monoclonal anti-idiotypic antibodies

International Nuclear Information System (INIS)

Conroy, W.G.

1988-01-01

Structural relatedness between the variable region of anti-ligand antibodies and opioid binding sites allowed the generation of anti-idiotypic antibodies which recognized opioid receptors. The IgG 3 k antibodies which bound to opioid receptors were obtained when an anti-morphine antiserum was the idiotype. Both antibodies bound to opioid receptors, but only one of these blocked the binding of [ 3 H]naloxone. The antibody which did not inhibit the binding of [ 3 H]naloxone was itself displaced from the receptor by opioid ligands. The unique binding properties displayed by this antibody indicated that anti-idiotypic antibodies are not always a perfect image of the original ligand, and therefore may be more useful than typical ligands as probes for the receptor. An auto-anti-idiotypic technique was successfully used to obtain anti-opioid receptor antibodies. Another IgG 3 k antibody that blocked the binding of [ 3 H]naloxone to rat brain opioid receptors was obtained when a mouse was immunized with naloxone conjugated to bovine serum albumin. These data confirmed that an idiotype-anti-idiotype network which can generate an anti-receptor antibody normally functions when an opioid ligand is introduced into an animal in an immunogenic form

Influenza human monoclonal antibody 1F1 interacts with three major antigenic sites and residues mediating human receptor specificity in H1N1 viruses.

Directory of Open Access Journals (Sweden)

Tshidi Tsibane

Full Text Available Most monoclonal antibodies (mAbs to the influenza A virus hemagglutinin (HA head domain exhibit very limited breadth of inhibitory activity due to antigenic drift in field strains. However, mAb 1F1, isolated from a 1918 influenza pandemic survivor, inhibits select human H1 viruses (1918, 1943, 1947, and 1977 isolates. The crystal structure of 1F1 in complex with the 1918 HA shows that 1F1 contacts residues that are classically defined as belonging to three distinct antigenic sites, Sa, Sb and Ca(2. The 1F1 heavy chain also reaches into the receptor binding site (RBS and interacts with residues that contact sialoglycan receptors and determine HA receptor specificity. The 1F1 epitope is remarkably similar to the previously described murine HC63 H3 epitope, despite significant sequence differences between H1 and H3 HAs. Both antibodies potently inhibit receptor binding, but only HC63 can block the pH-induced conformational changes in HA that drive membrane fusion. Contacts within the RBS suggested that 1F1 may be sensitive to changes that alter HA receptor binding activity. Affinity assays confirmed that sequence changes that switch the HA to avian receptor specificity affect binding of 1F1 and a mAb possessing a closely related heavy chain, 1I20. To characterize 1F1 cross-reactivity, additional escape mutant selection and site-directed mutagenesis were performed. Residues 190 and 227 in the 1F1 epitope were found to be critical for 1F1 reactivity towards 1918, 1943 and 1977 HAs, as well as for 1I20 reactivity towards the 1918 HA. Therefore, 1F1 heavy-chain interactions with conserved RBS residues likely contribute to its ability to inhibit divergent HAs.

Monoclonal antibody 6E4 against human GAPDHS protein

Czech Academy of Sciences Publication Activity Database

Dorosh, Andriy

2011-01-01

Roč. 30, č. 3 (2011), s. 321-321 ISSN 1554-0014 Institutional research plan: CEZ:AV0Z50520701 Keywords : Monoclonal antibody * GAPDHS Subject RIV: EI - Biotechnology ; Bionics Impact factor: 0.417, year: 2011

Molecular analysis of the nerve growth factor receptor

International Nuclear Information System (INIS)

Hempstead, B.; Patil, N.; Olson, K.; Chao, M.

1988-01-01

An essential molecule in the translocation of information by nerve growth factor (NGF) to responsive cells is the cell-surface receptor for NGF. This paper presents information on the genomic structure of the NGF receptor gene, NGF receptor models, and transfection of NGF receptors. Equilibrium binding of [ 125 I]NGF to cells reveals two distinct affinity states for the NGF receptor. The human NGF receptor gene is a single-copy gene, consisting of six exons that span 23 kb. The receptor gene is capable of being transferred to fibroblast cells from human genomic DNA and expressed at high levels. The constitutive nature of the receptor promoter sequence is a partial explanation of why this tissue-specific gene is expressed efficiently in a variety of nonneuronal cells after genomic gene transfer. The two kinetic forms of the NGF receptor appear to be encoded by the same protein, which is the product of a single gene

Human monoclonal antibodies against glucagon receptor improve glucose homeostasis by suppression of hepatic glucose output in diet-induced obese mice.

Directory of Open Access Journals (Sweden)

Wook-Dong Kim

Full Text Available AIM: Glucagon is an essential regulator of hepatic glucose production (HGP, which provides an alternative therapeutic target for managing type 2 diabetes with glucagon antagonists. We studied the effect of a novel human monoclonal antibody against glucagon receptor (GCGR, NPB112, on glucose homeostasis in diet-induced obese (DIO mice. METHODS: The glucose-lowering efficacy and safety of NPB112 were investigated in DIO mice with human GCGR for 11 weeks, and a hyperinsulinemic-euglycemic clamp study was conducted to measure HGP. RESULTS: Single intraperitoneal injection of NPB112 with 5 mg/kg effectively decreased blood glucose levels in DIO mice for 5 days. A significant reduction in blood glucose was observed in DIO mice treated with NPB112 at a dose ≥5 mg/kg for 6 weeks, and its glucose-lowering effect was dose-dependent. Long-term administration of NPB112 also caused a mild 29% elevation in glucagon level, which was returned to the normal range after discontinuation of treatment. The clamp study showed that DIO mice injected with NPB112 at 5 mg/kg were more insulin sensitive than control mice, indicating amelioration of insulin resistance by treatment with NPB112. DIO mice treated with NPB112 showed a significant improvement in the ability of insulin to suppress HGP, showing a 33% suppression (from 8.3 mg/kg/min to 5.6 mg/kg/min compared to the 2% suppression (from 9.8 mg/kg/min to 9.6 mg/kg/min in control mice. In addition, no hypoglycemia or adverse effect was observed during the treatment. CONCLUSIONS: A novel human monoclonal GCGR antibody, NPB112, effectively lowered the glucose level in diabetic animal models with mild and reversible hyperglucagonemia. Suppression of excess HGP with NPB112 may be a promising therapeutic modality for the treatment of type 2 diabetes.

A panel of recombinant monoclonal antibodies against zebrafish neural receptors and secreted proteins suitable for wholemount immunostaining.

Science.gov (United States)

Staudt, Nicole; Müller-Sienerth, Nicole; Fane-Dremucheva, Alla; Yusaf, Shahnaz P; Millrine, David; Wright, Gavin J

2015-01-02

Cell surface receptors and secreted proteins play important roles in neural recognition processes, but because their site of action can be a long distance from neuron cell bodies, antibodies that label these proteins are valuable to understand their function. The zebrafish embryo is a popular vertebrate model for neurobiology, but suffers from a paucity of validated antibody reagents. Here, we use the entire ectodomain of neural zebrafish cell surface or secreted proteins expressed in mammalian cells to select monoclonal antibodies to ten different antigens. The antibodies were characterised by Western blotting and the sensitivity of their epitopes to formalin fixation was determined. The rearranged antigen binding regions of the antibodies were amplified and cloned which enabled expression in a recombinant form from a single plasmid. All ten antibodies gave specific staining patterns within formalin-treated embryonic zebrafish brains, demonstrating that this generalised approach is particularly efficient to elicit antibodies that stain native antigen in fixed wholemount tissue. Finally, we show that additional tags can be easily added to the recombinant antibodies for convenient multiplex staining. The antibodies and the approaches described here will help to address the lack of well-defined antibody reagents in zebrafish research. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Antiproliferative and apoptotic effects of a specific anti-insulin-like growth factor I receptor single chain antibody on breast cancer cells.

Science.gov (United States)

Motallebnezhad, Morteza; Younesi, Vahid; Aghebati-Maleki, Leili; Nickho, Hamid; Safarzadeh, Elham; Ahmadi, Majid; Movassaghpour, Ali Akbar; Hosseini, Ahmad; Yousefi, Mehdi

2016-11-01

Insulin-like growth factor I receptor (IGF-IR) is expressed on breast cancer cells and involves in metastasis, survival, and proliferation. Currently, application of IGF-IR-targeting monoclonal antibodies (mAbs), alone or in combination with other drugs, is a promising strategy for breast cancer therapy. Single-chain fragment variable (scFv) antibodies have been introduced as appropriate tools for tumor-targeting purposes because of their advantages over whole antibodies. In the present study, we employed a naïve phage library and isolated scFvs against a specific epitope from extracellular domain of IGF-IR by panning process. The selected scFvs were further characterized using polyclonal and monoclonal phage ELISA, soluble monoclonal ELISA, and colony PCR and sequencing. Antiproliferative and apoptotic effects of selected scFv antibodies on breast cancer cell lines were also evaluated by MTT and Annexin V/PI assays. The results of ELISA indicated specific reactions of the isolated scFvs against the IGF-IR peptide, and analyses of PCR product and sequencing confirmed the presence of full length V H and Vκ inserts. Treatment of MCF7 and SKBR3 cells with anti-IGF-IR scFv led to a significant growth inhibition. The results also showed that scFv treatment significantly augmented trastuzumab growth inhibitory effects on SKBR3 cells. The percentage of the apoptotic MCF7 and SKBR3 cells after 24-h treatment with scFv was 39 and 30.70 %, respectively. Twenty-four-hour treatment with scFv in combination with trastuzumab resulted in 44.75 % apoptosis of SKBR3 cells. Taken together, our results demonstrate that the targeting of IGF-IR by scFv can be an effective strategy in the treatment of breast cancer and provide further evidence for effectiveness of dual targeting of HER2 and IGF-IR in breast cancer therapy.

Therapeutic Recombinant Monoclonal Antibodies

Science.gov (United States)

Bakhtiar, Ray

2012-01-01

During the last two decades, the rapid growth of biotechnology-derived techniques has led to a myriad of therapeutic recombinant monoclonal antibodies with significant clinical benefits. Recombinant monoclonal antibodies can be obtained from a number of natural sources such as animal cell cultures using recombinant DNA engineering. In contrast to…

Emerging role of epidermal growth factor receptor inhibition in therapy for advanced malignancy: focus on NSCLC

International Nuclear Information System (INIS)

Langer, Corey J.

2004-01-01

Combination chemotherapy regimens have emerged as the standard approach in advanced non-small-cell lung cancer. Meta-analyses have demonstrated a 2-month increase in median survival after platinum-based therapy vs. best supportive care, and an absolute 10% improvement in the 1-year survival rate. Just as importantly, cytotoxic therapy has produced benefits in symptom control and quality of life. Newer agents, including the taxanes, vinorelbine, gemcitabine, and irinotecan, have expanded our therapeutic options in the treatment of advanced non-small-cell lung cancer. Despite their contributions, we have reached a therapeutic plateau, with response rates seldom exceeding 30-40% in cooperative group studies and 1-year survival rates stable between 30% and 40%. It is doubtful that substituting one agent for another in various combinations will lead to any further improvement in these rates. The thrust of current research has focused on targeted therapy, and epidermal growth factor receptor inhibition is one of the most promising clinical strategies. Epidermal growth factor receptor inhibitors currently under investigation include the small molecules gefitinib (Iressa, ZD1839) and erlotinib (Tarceva, OSI-774), as well as monoclonal antibodies such as cetuximab (IMC-225, Erbitux). Agents that have only begun to undergo clinical evaluation include CI-1033, an irreversible pan-erbB tyrosine kinase inhibitor, and PKI166 and GW572016, both examples of dual kinase inhibitors (inhibiting epidermal growth factor receptor and Her2). Preclinical models have demonstrated synergy for all these agents in combination with either chemotherapy or radiotherapy, leading to great enthusiasm regarding their ultimate contribution to lung cancer therapy. However, serious clinical challenges persist. These include the identification of the optimal dose(s); the proper integration of these agents into popular, established cytotoxic regimens; and the selection of the optimal setting(s) in which

Technetium-99m direct radiolabeling of monoclonal antibody ior egf/r3

Energy Technology Data Exchange (ETDEWEB)

Morales, Alejo A. Morales; Crespo, Francisco Zayas; Gandolff, Gilda Nunez; Escobar, Normando Iznaga; Perez, Niuvis Perez; Hernandez, Juan C. Izquierdo

1998-01-01

Monoclonal antibodies (MAbs) are being widely used for imaging studies, coupled mainly with {sup 99m}Tc. The antibody ior egf/r3 is a MAb against human epidermal growth factor receptor (hEGF-r), and we have developed a method for optimum labeling of this MAb with {sup 99m}Tc. The reduction was performed with 2-mercaptoethanol (2-ME) at a molar ratio of 2000:1 (2-ME:MAb) and methylene diphosphonate as transchelant. The integrity of reduced MAb was checked by mean of native polyacrylamide gel electrophoresis (PAGE) and gel filtration chromatography on Superose 12 (purity >99%). Radio colloids remained lower than 2%, and the labeling efficiency was 98.5%. The number of sulfhydryl groups generated was quantified using Ellman's reagent and was found to be 6.65 {+-} 0.69 per antibody molecule. In vitro stability studies in several challenging conditions (DTPA, human serum albumin and human serum) were performed, and no significant loss in binding percentage was seen. Radio receptor assay was used to test immunoreactivity of the reduced MAb. Both labeled and unlabeled MAbs were able to compete for binding to the hEGF-r with radioiodinated EGF. Biodistribution studies in BALB/c mice are reported.

Technetium-99m direct radiolabeling of monoclonal antibody ior egf/r3

International Nuclear Information System (INIS)

Morales, Alejo A. Morales; Crespo, Francisco Zayas; Gandolff, Gilda Nunez; Escobar, Normando Iznaga; Perez, Niuvis Perez; Hernandez, Juan C. Izquierdo

1998-01-01

Monoclonal antibodies (MAbs) are being widely used for imaging studies, coupled mainly with 99m Tc. The antibody ior egf/r3 is a MAb against human epidermal growth factor receptor (hEGF-r), and we have developed a method for optimum labeling of this MAb with 99m Tc. The reduction was performed with 2-mercaptoethanol (2-ME) at a molar ratio of 2000:1 (2-ME:MAb) and methylene diphosphonate as transchelant. The integrity of reduced MAb was checked by mean of native polyacrylamide gel electrophoresis (PAGE) and gel filtration chromatography on Superose 12 (purity >99%). Radio colloids remained lower than 2%, and the labeling efficiency was 98.5%. The number of sulfhydryl groups generated was quantified using Ellman's reagent and was found to be 6.65 ± 0.69 per antibody molecule. In vitro stability studies in several challenging conditions (DTPA, human serum albumin and human serum) were performed, and no significant loss in binding percentage was seen. Radio receptor assay was used to test immunoreactivity of the reduced MAb. Both labeled and unlabeled MAbs were able to compete for binding to the hEGF-r with radioiodinated EGF. Biodistribution studies in BALB/c mice are reported

Growth factor receptors as molecular targets for cancer diagnosis and therapy

International Nuclear Information System (INIS)

Zalutsky, M. R.

1997-01-01

Growth factor receptors are of great interest as molecular targets for the diagnosis and treatment of cancer. Growth factor receptors are frequently over expressed on malignant cell populations since many cellular oncogenes encode either growth factors of their receptors. The wild-type epidermal growth factor receptor has a molecular weight of 170 kD and is over expressed on gliomas, bladder tumors, squamous cells carcinomas and breast carcinomas. Another growth factor oncogene, c-erb B-2, encodes a 185-kD glycoprotein found on the surface of gliomas, breast and ovarian cancers as well as other carcinomas of epithelial origin. In addition to causing over expression, oncogenic transformation also can result in genomic re-arrangements. An important example from the perspective of targeting is EGFRvIII, a deletion mutant which lacks amino acids 6-273 in the extracellular domain of the epiderma growth factor receptor. The EGFRvIII molecule (145 kD) may be of great value for targeting because it appears to be tumor-specific. Antibodies have been developed with specific reactivity with these growth factor receptors. Since these antibodies are internalized into the cell after receptor binding, it is necessary to use radiolabeling methods which residualize the radioactivity in the tumor cell after intracellular catabolism. To investigate this problem they have evaluated the effect of radioiodination method on the in vitro an in vivo properties of an anti-EGFRvIII antibody. Methods studied were Iodogen, tyramine-cellobiose, and N-succinimidyl 5-iodo-3-pyridine-carboxylate with the last offering optimal localization in a human xenograft model

Role of the multichain IL-2 receptor complex in the control of normal and malignant T-cell proliferation

International Nuclear Information System (INIS)

Waldmann, T.A.

1987-01-01

Antigen-induced activation of resting T-cells induces the synthesis of interleukin-2 (IL-2), as well as the expression of specific cell surface receptors for this lymphokine. There are at least two forms of the cellular receptors for IL-2, one with a very high affinity and the other with a lower affinity. The authors have identified two IL-2 binding peptides, a 55-kd peptide reactive with the anti-Tac monoclonal antibody, and a novel 75-kd non-Tac IL-2 binding peptide. Cell lines bearing either the p55, Tac, or the p75 peptide along manifested low-affinity IL-2 binding, whereas cell lines bearing both peptides manifested both high- and low-affinity receptors. Fusion of cell membranes from low-affinity IL-2 binding cells bearing the Tac peptide alone with membranes from a cell line bearing the p75 peptide alone generates hybrid membranes bearing high-affinity receptors. They propose a multichain model for the high-affinity IL-2 receptor in which both the Tac and the p75 IL-2 binding peptides are associated in a receptor complex. In contrast to resting T-cells, human T-cell lymphotropic virus I-associated adult T-cell leukemia cells constitutively express large numbers of IL-2 receptors. Because IL-2 receptors are present on the malignant T-cells but not on normal resting cells, clinical trials have been initiated in which patients with adult T-cell leukemia are being treated with either unmodified or toxin-conjugated forms of anti-Tac monoclonal antibody directed toward this growth factor receptor. Cross-linking studies were done using [ 125 I] IL-2

Comparative tumour localization properties of radiolabelled monoclonal antibody preparations of defined immunoreactivities

International Nuclear Information System (INIS)

Pimm, M.V.; Baldwin, R.W.

1987-01-01

The immunoreactive fraction of an anti-CEA monoclonal antibody preparation has been progressively decreased by the addition of increasing proportions of impurity in the form of immunologically inert mouse immunoglobulin. Following radioiodination, the immunoreactive fractions of the preparations were determined and their localization in a human tumour xenograft in nude mice was assessed. There was a progressive decline in tumour localization, from tumour to blood ratios of 2:1 with unadulterated antibody to 0.6:1 with preparations only 15% with respect to the initial antibody. These findings demonstrate that the immunoreactive fraction of monoclonal antibody preparations is a major limiting factor in tumour localization and this has implications for experimental and clinical applications of monoclonal antibodies. (orig.)

New monoclonal antibody to human apolipoprotein J

Czech Academy of Sciences Publication Activity Database

Čapková, Jana; Geussová, Gizela; Pěknicová, Jana

2002-01-01

Roč. 2002, č. 48 (2002), s. 40-42 ISSN 0015-5500 R&D Projects: GA ČR GV524/96/K162 Grant - others:NFDK-MAOB(XE) 1985-NFDK-MAOB Institutional research plan: CEZ:AV0Z5052915 Keywords : apo J * human spermatoza * monoclonal antibody Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.615, year: 2002

Development of real-time reverse transcription polymerase chain reaction assays to quantify insulin-like growth factor receptor and insulin receptor expression in equine tissue

Directory of Open Access Journals (Sweden)

Stephen B. Hughes

2013-08-01

Full Text Available The insulin-like growth factor system (insulin-like growth factor 1, insulin-like growth factor 2, insulin-like growth factor 1 receptor, insulin-like growth factor 2 receptor and six insulin-like growth factor-binding proteins and insulin are essential to muscle metabolism and most aspects of male and female reproduction. Insulin-like growth factor and insulin play important roles in the regulation of cell growth, differentiation and the maintenance of cell differentiation in mammals. In order to better understand the local factors that regulate equine physiology, such as muscle metabolism and reproduction (e.g., germ cell development and fertilisation, real-time reverse transcription polymerase chain reaction assays for quantification of equine insulin-like growth factor 1 receptor and insulin receptor messenger ribonucleic acid were developed. The assays were sensitive: 192 copies/µLand 891 copies/µL for insulin-like growth factor 1 receptor, messenger ribonucleic acid and insulin receptor respectively (95%limit of detection, and efficient: 1.01 for the insulin-like growth factor 1 receptor assay and 0.95 for the insulin receptor assay. The assays had a broad linear range of detection (seven logs for insulin-like growth factor 1 receptor and six logs for insulin receptor. This allowed for analysis of very small amounts of messenger ribonucleic acid. Low concentrations of both insulin-like growth factor 1 receptor and insulin receptor messenger ribonucleic acid were detected in endometrium, lung and spleen samples, whilst high concentrations were detected in heart, muscle and kidney samples, this was most likely due to the high level of glucose metabolism and glucose utilisation by these tissues. The assays developed for insulin-like growth factor 1 receptor and insulin receptor messenger ribonucleic acid expression have been shown to work on equine tissue and will contribute to the understanding of insulin and insulin-like growth factor 1

Identification and in vitro characterization of novel nanobodies against human granulocyte colony-stimulating factor receptor to provide inhibition of G-CSF function.

Science.gov (United States)

Bakherad, Hamid; Gargari, Seyed Latif Mousavi; Sepehrizadeh, Zargham; Aghamollaei, Hossein; Taheri, Ramezan Ali; Torshabi, Maryam; Yazdi, Mojtaba Tabatabaei; Ebrahimizadeh, Walead; Setayesh, Neda

2017-09-01

It has been shown that Granulocyte colony-stimulating factor (G-CSF) has a higher expression in malignant tumors, and anti-G-CSF therapy considerably decreases tumor growth, tumor vascularization and metastasis. Thus, blocking the signaling pathway of G-CSF could be beneficial in cancer therapy. This study is aimed at designing and producing a monoclonal nanobody that could act as an antagonist of G-CSF receptor. Nanobodies are the antigen binding fragments of camelid single-chain antibodies, also known as VHH. These fragments have exceptional properties which makes them ideal for tumor imaging and therapeutic applications. We have used our previously built nanobody phage libraries to isolate specific nanobodies to the G-CSF receptor. After a series of cross-reactivity and affinity experiments, two unique nanobodies were selected for functional analysis. Proliferation assay, real-time PCR and immunofluorescence assays were used to characterize these nanobodies. Finally, VHH26 nanobody that was able to specifically bind G-CSF receptor (G-CSF-R) on the surface of NFS60 cells and efficiently block G-CSF-R downstream signaling pathway in a dose-dependent manner was selected. This nanobody could be further developed into a valuable tool in tumor therapy and it forms a basis for additional studies in preclinical animal models. Copyright © 2017. Published by Elsevier Masson SAS.

Hepatocyte and keratinocyte growth factors and their receptors in human lung emphysema

Directory of Open Access Journals (Sweden)

Marchal Joëlle

2005-10-01

Full Text Available Abstract Background Hepatocyte and keratinocyte growth factors are key growth factors in the process of alveolar repair. We hypothesized that excessive alveolar destruction observed in lung emphysema involves impaired expression of hepatocyte and keratinocyte growth factors or their respective receptors, c-met and keratinocyte growth factor receptor. The aim of our study was to compare the expression of hepatocyte and keratinocyte growth factors and their receptors in lung samples from 3 groups of patients: emphysema; smokers without emphysema and non-smokers without emphysema. Methods Hepatocyte and keratinocyte growth factor proteins were analysed by immunoassay and western blot; mRNA expression was measured by real time quantitative polymerase chain reaction. Results Hepatocyte and keratinocyte growth factors, c-met and keratinocyte growth factor receptor mRNA levels were similar in emphysema and non-emphysema patients. Hepatocyte growth factor mRNA correlated negatively with FEV1 and the FEV1/FVC ratio both in emphysema patients and in smokers with or without emphysema. Hepatocyte and keratinocyte growth factor protein concentrations were similar in all patients' groups. Conclusion The expression of hepatocyte and keratinocyte growth factors and their receptors is preserved in patients with lung emphysema as compared to patients without emphysema. Hepatocyte growth factor mRNA correlates with the severity of airflow obstruction in smokers.

Rheumatoid factor interference in immunogenicity assays for human monoclonal antibody therapeutics.

Science.gov (United States)

Tatarewicz, Suzanna; Miller, Jill M; Swanson, Steven J; Moxness, Michael S

2010-05-31

Rheumatoid factors (RFs) are endogenous human antibodies that bind to human gamma globulins. RFs demonstrate preferential binding to aggregated gamma globulins and are involved in the clearing mechanism of immune complexes. Immunoassays designed to measure human anti-human antibodies (HAHA) after administration of monoclonal antibody therapeutics are thus vulnerable to interference from RFs. When using a sensitive electrochemiluminescent (ECL) bridging immunoassay, samples from subjects with rheumatoid arthritis demonstrated much higher baseline reactivity than healthy subjects. Interference was found to be dependent on the aggregation state of the therapeutic antibody that had been conjugated with the detection reagent (ruthenium). Size exclusion high performance liquid chromatography (SE-HPLC) demonstrated that of the total integrated peaks, as little as 0.55% high molecular weight aggregates (>600kDa) were sufficient to cause increased reactivity. Stability studies of the ruthenium and biotin conjugated therapeutic antibody indicated that storage time, temperature and buffer formulation were critical in maintaining the integrity of the reagents. Through careful SE-HPLC monitoring we were able to choose appropriate storage and buffer conditions which led to a reduction in the false reactivity rate in therapeutic-naïve serum from a rheumatoid arthritis population.

Glycosylation as a Main Regulator of Growth and Death Factor Receptors Signaling

Directory of Open Access Journals (Sweden)

Inês Gomes Ferreira

2018-02-01

Full Text Available Glycosylation is a very frequent and functionally important post-translational protein modification that undergoes profound changes in cancer. Growth and death factor receptors and plasma membrane glycoproteins, which upon activation by extracellular ligands trigger a signal transduction cascade, are targets of several molecular anti-cancer drugs. In this review, we provide a thorough picture of the mechanisms bywhich glycosylation affects the activity of growth and death factor receptors in normal and pathological conditions. Glycosylation affects receptor activity through three non-mutually exclusive basic mechanisms: (1 by directly regulating intracellular transport, ligand binding, oligomerization and signaling of receptors; (2 through the binding of receptor carbohydrate structures to galectins, forming a lattice thatregulates receptor turnover on the plasma membrane; and (3 by receptor interaction with gangliosides inside membrane microdomains. Some carbohydrate chains, for example core fucose and β1,6-branching, exert a stimulatory effect on all receptors, while other structures exert opposite effects on different receptors or in different cellular contexts. In light of the crucial role played by glycosylation in the regulation of receptor activity, the development of next-generation drugs targeting glyco-epitopes of growth factor receptors should be considered a therapeutically interesting goal.

Affinity isolation of antigen-specific circulating B cells for generation of phage display-derived human monoclonal antibodies

DEFF Research Database (Denmark)

Ditzel, Henrik

2009-01-01

A method is described for affinity isolation of antigen-specific circulating B cells of interest for subsequent generation of immune antibody phage display libraries. This approach should overcome the problem of low yields of monoclonal antibodies of interest in the libraries generated from...... peripheral blood lymphocytes caused by the low abundance of antigen-specific B cells in the circulation. The preselection of B cells is based on the specificity of the surface Ig receptor and is accomplished using the antigen of interest conjugated to magnetic beads. This method should significantly increase...... the frequency of antibody phage particles of interest in the library and allow for efficient isolation monoclonal antibodies with the predefined specificity....

Chimeric opioid peptides: tools for identifying opioid receptor types.

OpenAIRE

Xie, G X; Miyajima, A; Yokota, T; Arai, K; Goldstein, A

1990-01-01

We synthesized several chimeric peptides in which the N-terminal nine residues of dynorphin-32, a peptide selective for the kappa opioid receptor, were replaced by opioid peptides selective for other opioid receptor types. Each chimeric peptide retained the high affinity and type selectivity characteristic of its N-terminal sequence. The common C-terminal two-thirds of the chimeric peptides served as an epitope recognized by the same monoclonal antibody. When bound to receptors on a cell surf...

A monoclonal antibody TrkB receptor agonist as a potential therapeutic for Huntington's disease.

Directory of Open Access Journals (Sweden)

Daniel Todd

Full Text Available Huntington's disease (HD is a devastating, genetic neurodegenerative disease caused by a tri-nucleotide expansion in exon 1 of the huntingtin gene. HD is clinically characterized by chorea, emotional and psychiatric disturbances and cognitive deficits with later symptoms including rigidity and dementia. Pathologically, the cortico-striatal pathway is severely dysfunctional as reflected by striatal and cortical atrophy in late-stage disease. Brain-derived neurotrophic factor (BDNF is a neuroprotective, secreted protein that binds with high affinity to the extracellular domain of the tropomyosin-receptor kinase B (TrkB receptor promoting neuronal cell survival by activating the receptor and down-stream signaling proteins. Reduced cortical BDNF production and transport to the striatum have been implicated in HD pathogenesis; the ability to enhance TrkB signaling using a BDNF mimetic might be beneficial in disease progression, so we explored this as a therapeutic strategy for HD. Using recombinant and native assay formats, we report here the evaluation of TrkB antibodies and a panel of reported small molecule TrkB agonists, and identify the best candidate, from those tested, for in vivo proof of concept studies in transgenic HD models.

COLOCALIZATION OF MUSCARINIC AND NICOTINIC RECEPTORS IN CHOLINOCEPTIVE NEURONS OF THE SUPRACHIASMATIC REGION IN YOUNG AND AGED RATS

NARCIS (Netherlands)

VANDERZEE, EA; STREEFLAND, C; STROSBERG, AD; SCHRODER, H; LUITEN, PGM; Schröder, H.

1991-01-01

In the present study muscarinic and nicotinic cholinergic receptors in the SCN region were demonstrated and analyzed, employing monoclonal antibodies to purified muscarinic and nicotinic cholinergic receptor proteins. A near-total colocalization of the two acetylcholine receptor subclasses in

Monoclonal antibodies to Pneumocystis carinii

DEFF Research Database (Denmark)

Kovacs, J A; Halpern, J L; Lundgren, B

1989-01-01

To increase understanding of the antigenic structure of Pneumocystis carinii, we developed monoclonal antibodies to rat and human P. carinii. The specificity of the antibodies was demonstrated by immunofluorescence and immunoblot studies. Only one of five monoclonal antibodies to rat P. carinii r...

Cell-induced potentiation of the plasminogen activation system is abolished by a monoclonal antibody that recognizes the NH2-terminal domain of the urokinase receptor

DEFF Research Database (Denmark)

Rønne, E; Behrendt, N; Ellis, V

1991-01-01

We have raised four monoclonal antibodies recognizing different epitopes within the human cell-surface receptor for urokinase-type plasminogen activator (u-PA). One of these antibodies completely abolishes the potentiation of plasmin generation observed upon incubation of the zymogens pro......-u-PA and plasminogen with U937 cells. This antibody, which is also the only one to completely inhibit the binding of DFP-inactivated [125I]-u-PA to U937 cells, is directed against the u-PA binding NH2-terminal domain of u-PAR, a well-defined fragment formed by limited chymotrypsin digestion of purified u......-PAR, demonstrating the functional independence of the u-PA binding domain as well as the critical role of u-PAR in the assembly of the cell-surface plasminogen activation system....

Reactivity of eleven anti-human leucocyte monoclonal antibodies with lymphocytes from several domestic animals

DEFF Research Database (Denmark)

Aasted, Bent; Blixenkrone-Møller, Merete; Larsen, Else Bang

1988-01-01

Nine commercially available monoclonal antibodies and two monoclonal antibodies from The American Type Culture Collection, raised against various human leucocyte surface antigens, were tested on lymphocytes from cow, sheep, goat, swine, horse, cat, dog, mink, and rabbit as well as man. Four...... antibodies bound to lymphocytes from some of the animals. These were the antibodies against CD8 and CD4 antigen, the antibody to C3b-receptor, and the antibody to the HLA-DR antigen. The CD8 antigen-reactive antibody reacted with lymphocytes from mink, cat, dog, and sheep, while the CD4 antigen......-reactive antibody reacted with lymphocytes from mink. The anti-C3b-R antibody reacted with lymphocytes from horse, swine, dog, and cat, and the anti-HLA-DR reacted with lymphocytes from cow, goat, sheep, horse, dog, cat, and mink....

Monoclonal antibody therapy for neuromyelitis optica spectrum disorder: current and future.

Science.gov (United States)

Lin, Jie; Xue, Binbin; Li, Xiang; Xia, Junhui

2017-08-01

Monoclonal-antibody has been used for patients with autoimmune disorders for several years, and efficacy and safety were appreciated for these patients. Neuromyelitis optica specturm disorder (NMOSD) has been defined as an autoimmune demyelination disorder of the central nervous system (CNS) with a course of relapse-remission. Treatment of prevention is important for patients with NMOSD because of the increased disability after several attacks. Multiple factors were involved in the pathogenesis of NMOSD. Currently, targeting specific factor was favored in the research into the treatment for NMOSD. Previous studies reported the efficacy and tolerance in NMOSD for drugs such as rituximab, tocilizumab, and eculizumab. The aim of this article is to review the current monoclonal therapies for NMOSD patients, and also future alternative options.

Cuban Monoclonal Antibodies for Radioimmunodiagnosis and Radioimmunotherapy of Cancer Diseases

International Nuclear Information System (INIS)

Casaco, A.

2009-01-01

The Centre of Molecular Immunology produces monoclonal antibodies for treating cancer diseases. We are mainly focus on two target systems; one is the epidermal growth factor receptor (EGF-R) because there is a tremendous relationship between the EGF/EGF-R system and several human tumours such as lung, head and neck, ovarian breast and brain cancers; the second one is the ganglioside system, the relevance of certain gangliosides in tumour growth and metastatic dissemination has been well documented, GM3(NeuGc) ganglioside is particularly interesting due to its restrictive expression in normal human tissues. Nimotuzumab (h-R3) is a humanized monoclonal antibody (mAb) that was obtained by complementarity-determining regions grafting of a murine mAb (ior egf/r3) to a human framework having remarkable antiproliferative, pro-apoptotic, and antiangiogenic effects. A Phase I clinical trial was performed to evaluate the toxicity and clinical effect of an intracavitary (intracerebral) administration of a single dose of nimotuzumab (h-R3) labelled with increasing doses of 188Re. All patients bearing astrocytomas grade III/IV should be treated previously with conventional therapies and have an EGF-R overexpression in the tumour, demonstrated by immunohistochemical study. Maximal tolerated dose was 3 mg of the h-R3 labelled with 10 mCi of 188 Re. The radioimmunoconjugate showed a high retention in the surgical created resection cavity and the brain adjacent tissues with a mean value of 85.5% of the injected dose one hour post-administration. This radioimmunoconjugate may be relatively safe and a promising therapeutic approach for treating high grade gliomas. GM3(NeuGc) ganglioside is particularly interesting due to its restrictive expression in normal human tissues according to immunohistochemical studies, using either polyclonal or monoclonal antibodies. But both immunohistochemical and biochemical methods have strongly suggested its over-expression in human breast and colon

Signal transduction by the platelet-derived growth factor receptor

International Nuclear Information System (INIS)

Williams, L.T.; Escobedo, J.A.; Keating, M.T.; Coughlin, S.R.

1988-01-01

The mitogenic effects of platelet-derived growth factor (PDGF) are mediated by the PDGF receptor. The mouse PDGF receptor was recently purified on the basis of its ability to become tyrosine phosphorylated in response to the A-B human platelet form of PDGF, and the receptor amino acid sequence was determined from a full-length cDNA clone. Both the human and mouse receptor cDNA sequences have been expressed in Chinese hamster ovary fibroblast (CHO) cells that normally lack PDGF receptors. This paper summarizes recent results using this system to study signal transduction by the PDGF receptor. Some of the findings show that the KI domain of the PDGF receptor plays an important role in the stimulation of DNA synthesis by PDGF. Surprisingly, the kinase insert region is not essential for PDGF stimulation of PtdIns turnover, pH change, increase in cellular calcium, and receptor autophosphorylation. In addition, PDGF stimulates a conformational change in the receptor

Epitope mapping of functional domains of human factor V with human and mouse monoclonal antibodies

International Nuclear Information System (INIS)

Annamalai, A.E.; Rao, A.K.; Chiu, H.C.; Wang, D.; Dutta-Roy, A.K.; Colman, R.W.

1986-01-01

The authors previously described two human monoclonal antibodies (MAbs) which inactivated factor V. The authors have now purified the predominant antibody (H2) on protein A Sepharose using a pH gradient and typed it as IgG 1 ,. Immunoprecipitation of 125 I-human factor Va with H2 demonstrated specificity for the heavy chain (D), Mr = 105,000. The authors compared using ELISA the competitive binding to factor Va, of H2, H1 and two mouse MAbs, B38 (directed to E) and B10 (to activation peptide, Cl). All four antibodies recognized distinct epitopes in factor V with steric overlap in some cases. Factor Xa showed a concentration dependent competition for binding of H1, H2 and B38 but not B10 to factor V/Va in ELISA. All MAbs bound to factor V/Va in the absence of Ca ++ . However, Ca ++ at 8 mM increased the binding of H1 and H2 to 165% and 360% and did not have any effect on the binding of either mouse MAbs. Prothrombin at a concentration of up to 400 μg/ml did not inhibit binding of any of these antibodies. Thus, both the light (E) and heavy (D) chains of factor Va but not the activation peptide (Cl) interact with factor Xa as defined by the MAbs. In addition, sites on both chains for Ca ++ are recognized by particular MAbs (H1 and H2). These studies increase their knowledge of the interactions of factor V domains in the formation of prothrombinase complex

Preparation and preclinical evaluation of (177)Lu-nimotuzumab targeting epidermal growth factor receptor overexpressing tumors

Czech Academy of Sciences Publication Activity Database

Beckford, Denis R.; Eigner, Sebastian; Eigner-Henke, Kateřina; Lebeda, Ondřej; Melichar, František; Beran, Miloš

2012-01-01

Roč. 39, č. 1 (2012), s. 3-13 ISSN 0969-8051 R&D Projects: GA MŠk 2B06165 Institutional research plan: CEZ:AV0Z10480505 Keywords : Radioimmunotherapy * Nimotuzumab * (177)Lu * Monoclonal antibody Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 2.517, year: 2012

Monoclonal antibodies in oncology

International Nuclear Information System (INIS)

Chan, S.Y.T.; Sikora, K.

1986-01-01

Monoclonal antibodies (MCAs) can be used to differentiate between normal and neoplastic cells and thus exploited for diagnostic and, ultimately, therapeutic gain. The evidence for the existence of human tumour antigens is reviewed. Several areas of diagnosis are already benefiting from the application of the monoclonal technology. Immunohistology can help the pathologist with difficult diagnostic problems. New classifications of lymphoma and leukaemia can be based on specific surface molecules. Similarly, the detection of shed tumour antigens is already established as part of the routine assessment of many patients with common solid tumours. Isotopically labeled monoclonal antibodies have been used to localise primary and metastatic tumours. The use of antibodies in this way is not only a promising diagnostic tool but also the first step in studying the possibility of arming antibodies to provide therapeutic agents. Such trials are currently in progress. (Auth.)

Expression of growth factor receptors and targeting of EGFR in cholangiocarcinoma cell lines

International Nuclear Information System (INIS)

Xu, Ling; Hausmann, Martin; Dietmaier, Wolfgang; Kellermeier, Silvia; Pesch, Theresa; Stieber-Gunckel, Manuela; Lippert, Elisabeth; Klebl, Frank; Rogler, Gerhard

2010-01-01

Cholangiocarcinoma (CC) is a malignant neoplasm of the bile ducts or the gallbladder. Targeting of growth factor receptors showed therapeutic potential in palliative settings for many solid tumors. The aim of this study was to determine the expression of seven growth factor receptors in CC cell lines and to assess the effect of blocking the EGFR receptor in vitro. Expression of EGFR (epithelial growth factor receptor), HGFR (hepatocyte growth factor receptor) IGF1R (insulin-like growth factor 1 receptor), IGF2R (insulin-like growth factor 2 receptor) and VEGFR1-3 (vascular endothelial growth factor receptor 1-3) were examined in four human CC cell lines (EGI-1, HuH28, OZ and TFK-1). The effect of the anti-EGFR-antibody cetuximab on cell growth and apoptosis was studied and cell lines were examined for KRAS mutations. EGFR, HGFR and IGFR1 were present in all four cell lines tested. IGFR2 expression was confirmed in EGI-1 and TFK-1. No growth-inhibitory effect was found in EGI-1 cells after incubation with cetuximab. Cetuximab dose-dependently inhibited growth in TFK-1. Increased apoptosis was only seen in TFK-1 cells at the highest cetuximab dose tested (1 mg/ml), with no dose-response-relationship at lower concentrations. In EGI-1 a heterozygous KRAS mutation was found in codon 12 (c.35G>A; p.G12D). HuH28, OZ and TFK-1 lacked KRAS mutation. CC cell lines express a pattern of different growth receptors in vitro. Growth factor inhibitor treatment could be affected from the KRAS genotype in CC. The expression of EGFR itself does not allow prognoses on growth inhibition by cetuximab

Expression of growth factor receptors and targeting of EGFR in cholangiocarcinoma cell lines

Directory of Open Access Journals (Sweden)

Kellermeier Silvia

2010-06-01

Full Text Available Abstract Background Cholangiocarcinoma (CC is a malignant neoplasm of the bile ducts or the gallbladder. Targeting of growth factor receptors showed therapeutic potential in palliative settings for many solid tumors. The aim of this study was to determine the expression of seven growth factor receptors in CC cell lines and to assess the effect of blocking the EGFR receptor in vitro. Methods Expression of EGFR (epithelial growth factor receptor, HGFR (hepatocyte growth factor receptor IGF1R (insulin-like growth factor 1 receptor, IGF2R (insulin-like growth factor 2 receptor and VEGFR1-3 (vascular endothelial growth factor receptor 1-3 were examined in four human CC cell lines (EGI-1, HuH28, OZ and TFK-1. The effect of the anti-EGFR-antibody cetuximab on cell growth and apoptosis was studied and cell lines were examined for KRAS mutations. Results EGFR, HGFR and IGFR1 were present in all four cell lines tested. IGFR2 expression was confirmed in EGI-1 and TFK-1. No growth-inhibitory effect was found in EGI-1 cells after incubation with cetuximab. Cetuximab dose-dependently inhibited growth in TFK-1. Increased apoptosis was only seen in TFK-1 cells at the highest cetuximab dose tested (1 mg/ml, with no dose-response-relationship at lower concentrations. In EGI-1 a heterozygous KRAS mutation was found in codon 12 (c.35G>A; p.G12D. HuH28, OZ and TFK-1 lacked KRAS mutation. Conclusion CC cell lines express a pattern of different growth receptors in vitro. Growth factor inhibitor treatment could be affected from the KRAS genotype in CC. The expression of EGFR itself does not allow prognoses on growth inhibition by cetuximab.

Antibody-induced dimerization activates the epidermal growth factor receptor tyrosine kinase

NARCIS (Netherlands)

Spaargaren, M.; Defize, L. H.; Boonstra, J.; de Laat, S. W.

1991-01-01

The relationship between epidermal growth factor receptor (EGF-R) protein tyrosine kinase activation and ligand-induced receptor dimerization was investigated using several bivalent anti-EGF-R antibodies directed against various receptor epitopes. In A431 membrane preparations and permeabilized

Poliovirus Mutants Resistant to Neutralization with Soluble Cell Receptors

Science.gov (United States)

Kaplan, Gerardo; Peters, David; Racaniello, Vincent R.

1990-12-01

Poliovirus mutants resistant to neutralization with soluble cellular receptor were isolated. Replication of soluble receptor-resistant (srr) mutants was blocked by a monoclonal antibody directed against the HeLa cell receptor for poliovirus, indicating that the mutants use this receptor to enter cells. The srr mutants showed reduced binding to HeLa cells and cell membranes. However, the reduced binding phenotype did not have a major impact on viral replication, as judged by plaque size and one-step growth curves. These results suggest that the use of soluble receptors as antiviral agents could lead to the selection of neutralization-resistant mutants that are able to bind cell surface receptors, replicate, and cause disease.

A variety of human monoclonal antibodies against epidermal growth factor receptor isolated from a phage antibody library.

Science.gov (United States)

Kurosawa, Gene; Kondo, Mariko; Kurosawa, Yoshikazu

2016-11-04

When the technology for constructing human antibody (Ab) libraries using a phage-display system was developed, many researchers in Ab-related fields anticipated that it would be widely applied to the development of pharmaceutical drugs against various diseases, including cancers. However, successful examples of such applications are very limited. Moreover, researchers who utilize phage-display technology now show divergent ways of thinking about phage Ab libraries. For example, there is debate about what should be the source of V H and V L genes for the construction of libraries to cover the whole repertoire of Abs present in the human body. In the immune system, the introduction of mutations into V genes followed by selection based on binding activity, termed Ab maturation, is required for the production of Abs exhibiting high affinity to the antigen (Ag). Therefore, introduction of mutations and selection are required for isolation of Abs with high affinity after isolation of clones from phage Ab libraries. We constructed a large human Ab library termed AIMS, developed a screening method termed ICOS, and succeeded in isolating many human monoclonal Abs (mAbs) that specifically and strongly bind to various tumor-associated Ags. Eight anti-EGFR mAbs were included, which we characterized. These mAbs showed various different activities against EGFR-expressing cancer cells. In this paper, we describe these data and discuss the possibility and necessity that the mAbs isolated from the AIMS library might be developed as therapeutic drugs against cancers without introduction of mutations. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Regulation of Monoclonal Antibody Immunotherapy by FcγRIIB.

Science.gov (United States)

Stopforth, Richard J; Cleary, Kirstie L S; Cragg, Mark S

2016-05-01

Monoclonal antibodies (mAb) are revolutionising the treatment of many different diseases. Given their differing mode of action compared to most conventional chemotherapeutics and small molecule inhibitors, they possess the potential to be independent of common modes of treatment resistance and can typically be combined readily with existing treatments without dose-limiting toxicity. However, treatments with mAb rarely result in cure and so a full understanding of how these reagents work and can be optimised is key for their subsequent improvement. Here we review how an understanding of the biology of the inhibitory Fc receptor, FcγRIIB (CD32B), is leading to the development of improved mAb treatments.

Aggregates in monoclonal antibody manufacturing processes.

Science.gov (United States)

Vázquez-Rey, María; Lang, Dietmar A

2011-07-01

Monoclonal antibodies have proved to be a highly successful class of therapeutic products. Large-scale manufacturing of pharmaceutical antibodies is a complex activity that requires considerable effort in both process and analytical development. If a therapeutic protein cannot be stabilized adequately, it will lose partially or totally its therapeutic properties or even cause immunogenic reactions thus potentially further endangering the patients' health. The phenomenon of protein aggregation is a common issue that compromises the quality, safety, and efficacy of antibodies and can happen at different steps of the manufacturing process, including fermentation, purification, final formulation, and storage. Aggregate levels in drug substance and final drug product are a key factor when assessing quality attributes of the molecule, since aggregation might impact biological activity of the biopharmaceutical. In this review it is analyzed how aggregates are formed during monoclonal antibody industrial production, why they have to be removed and the manufacturing process steps that are designed to either minimize or remove aggregates in the final product. Copyright © 2011 Wiley Periodicals, Inc.

Clinical Translation and Validation of a Predictive Biomarker for Patritumab, an Anti-human Epidermal Growth Factor Receptor 3 (HER3) Monoclonal Antibody, in Patients With Advanced Non-small Cell Lung Cancer.

Science.gov (United States)

Mendell, Jeanne; Freeman, Daniel J; Feng, Wenqin; Hettmann, Thore; Schneider, Matthias; Blum, Sabine; Ruhe, Jens; Bange, Johannes; Nakamaru, Kenji; Chen, Shuquan; Tsuchihashi, Zenta; von Pawel, Joachim; Copigneaux, Catherine; Beckman, Robert A

2015-03-01

During early clinical development, prospective identification of a predictive biomarker and validation of an assay method may not always be feasible. Dichotomizing a continuous biomarker measure to classify responders also leads to challenges. We present a case study of a prospective-retrospective approach for a continuous biomarker identified after patient enrollment but defined prospectively before the unblinding of data. An analysis of the strengths and weaknesses of this approach and the challenges encountered in its practical application are also provided. HERALD (NCT02134015) was a double-blind, phase 2 study in patients with non-small cell lung cancer (NSCLC) randomized to erlotinib with placebo or with high or low doses of patritumab, a monoclonal antibody targeted against human epidermal growth factor receptor 3 (HER3). While the primary objective was to assess safety and progression-free survival (PFS), a secondary objective was to determine a single predictive biomarker hypothesis to identify subjects most likely to benefit from the addition of patritumab. Although not identified as the primary biomarker in the study protocol, on the basis of preclinical results from 2 independent laboratories, expression levels of the HER3 ligand heregulin (HRG) were prospectively declared the predictive biomarker before data unblinding but after subject enrollment. An assay to measure HRG mRNA was developed and validated. Other biomarkers, such as epidermal growth factor receptor (EGFR) mutation status, were also evaluated in an exploratory fashion. The cutoff value for high vs. low HRG mRNA levels was set at the median delta threshold cycle. A maximum likelihood analysis was performed to evaluate the provisional cutoff. The relationship of HRG values to PFS hazard ratios (HRs) was assessed as a measure of internal validation. Additional NSCLC samples were analyzed to characterize HRG mRNA distribution. The subgroup of patients with high HRG mRNA levels ("HRG

Antibodies and Selection of Monoclonal Antibodies.

Science.gov (United States)

Hanack, Katja; Messerschmidt, Katrin; Listek, Martin

Monoclonal antibodies are universal binding molecules with a high specificity for their target and are indispensable tools in research, diagnostics and therapy. The biotechnological generation of monoclonal antibodies was enabled by the hybridoma technology published in 1975 by Köhler and Milstein. Today monoclonal antibodies are used in a variety of applications as flow cytometry, magnetic cell sorting, immunoassays or therapeutic approaches. First step of the generation process is the immunization of the organism with appropriate antigen. After a positive immune response the spleen cells are isolated and fused with myeloma cells in order to generate stable, long-living antibody-producing cell lines - hybridoma cells. In the subsequent identification step the culture supernatants of all hybridoma cells are screened weekly for the production of the antibody of interest. Hybridoma cells producing the antibody of interest are cloned by limited dilution till a monoclonal hybridoma is found. This is a very time-consuming and laborious process and therefore different selection strategies were developed since 1975 in order to facilitate the generation of monoclonal antibodies. Apart from common automation of pipetting processes and ELISA testing there are some promising approaches to select the right monoclonal antibody very early in the process to reduce time and effort of the generation. In this chapter different selection strategies for antibody-producing hybridoma cells are presented and analysed regarding to their benefits compared to conventional limited dilution technology.

Factor XII (Hageman factor) is a missing link between stress and hypercoagulability and plays an important role in the pathophysiology of ischemic stroke.

Science.gov (United States)

Eggers, Arnold E

2006-01-01

ways of blocking stress-induced hypercoagulability and hypertension. Hypercoagulability could be targeted by monoclonal antibodies directed against the platelet-specific alpha-2 adrenergic receptor or the (putative) platelet receptor for Factor XII; hypertension could be treated with monoclonal antibodies directed against the beta-adrenergic receptor in the juxtaglomerular apparatus or by surgical denervation of the kidneys, either of which would decrease the renin release which helps drive the hypertension.

Human agonistic TRAIL receptor antibodies Mapatumumab and Lexatumumab induce apoptosis in malignant mesothelioma and act synergistically with cisplatin

Directory of Open Access Journals (Sweden)

Felley-Bosco Emanuela

2007-10-01

Full Text Available Abstract Background The incidence of malignant pleural mesothelioma (MPM is associated with exposure to asbestos, and projections suggest that the yearly number of deaths in Western Europe due to MPM will increase until 2020. Despite progress in chemo- and in multimodality therapy, MPM remains a disease with a poor prognosis. Inducing apoptosis by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL or agonistic monoclonal antibodies which target TRAIL-receptor 1 (TRAIL-R1 or TRAIL-R2 has been thought to be a promising cancer therapy. Results We have compared the sensitivity of 13 MPM cell lines or primary cultures to TRAIL and two fully human agonistic monoclonal antibodies directed to TRAIL-R1 (Mapatumumab and TRAIL-R2 (Lexatumumab and examined sensitization of the MPM cell lines to cisplatin-induced by the TRAIL-receptor antibodies. We found that sensitivity of MPM cells to TRAIL, Mapatumumab and Lexatumumab varies largely and is independent of TRAIL-receptor expression. TRAIL-R2 contributes more than TRAIL-R1 to death-receptor mediated apoptosis in MPM cells that express both receptors. The combination of cisplatin with Mapatumumab or Lexatumumab synergistically inhibited the cell growth and enhanced apoptotic death. Furthermore, pre-treatment with cisplatin followed by Mapatumumab or Lexatumumab resulted in significant higher cytotoxic effects as compared to the reverse sequence. Combination-induced cell growth inhibition was significantly abrogated by pre-treatment of the cells with the antioxidant N-acetylcysteine. Conclusion Our results suggest that the sequential administration of cisplatin followed by Mapatumumab or Lexatumumab deserves investigation in the treatment of patients with MPM.

Involvement of lymphocyte function-associated antigen-1 (LFA-1) in HIV infection: inhibition by monoclonal antibody

DEFF Research Database (Denmark)

Hansen, J E; Nielsen, C; Mathiesen, Lars Reinhardt

1991-01-01

Monoclonal antibodies (MAbs) against the alpha- and beta-chain of lymphocyte-associated antigen-1 (LFA-1) were examined for inhibition of HIV-1 infection in vitro. Infection of the T cell line MT4 and the monocytic cell line U937 by isolates HTLVIIIB and SSI-002, respectively was inhibited...... in a concentration dependent manner by MAb against the beta-chain but not against the alpha-chain. No cross-reactivity was found between MAb against LFA-1 and against the CD4 receptor (MAb Leu3a). MAbs against the beta-chain and the CD4 receptor were found to act synergistically in inhibiting HIV infection...

Topographic antigenic determinants recognized by monoclonal antibodies on human choriogonadotropin beta-subunit

International Nuclear Information System (INIS)

Bidart, J.M.; Troalen, F.; Salesse, R.; Bousfield, G.R.; Bohuon, C.J.; Bellet, D.H.

1987-01-01

We describe a first attempt to study the antibody-combining sites recognized by monoclonal antibodies raised against the beta-subunit of human choriogonadotropin (hCG). Two groups of antibodies were first defined by their ability to recognize only the free beta-subunit or the free and combined subunit. Antibodies FBT-11 and FBT-11-L bind only to hCG beta-subunit but not to hCG, whereas antibodies FBT-10 and D1E8 bind to both the beta-subunit and the hormone. In both cases, the antigenic determinants were localized to the core of the protein (residues 1-112), indicating the weak immunogenicity of the specific carboxyl-terminal extension of hCG-beta. Nine synthetic peptides spanning different regions of hCG-beta and lutropin-beta were assessed for their capacity to inhibit antibody binding. A synthetic peptide inclusive of the NH2-terminal region (residues 1-7) of the hCG beta-subunit was found to inhibit binding to the radiolabeled subunit of a monoclonal antibody specific for free hCG-beta (FBT-11). Further delineation of the antigenic site recognized by this antibody provided evidence for the involvement of fragment 82-92. Moreover, monoclonal antibody FBT-11 inhibited the recombination of hCG-beta to hCG-alpha, indicating that its antigenic determinant might be located nearby or in the hCG-beta portion interacting with the alpha-subunit. Binding of monoclonal antibody FBT-10, corresponding to the second antigenic determinant, was weakly inhibited by fragment 82-105 and did not impair the recombination of the hCG beta-subunit to the hCG alpha-subunit. Its combining site appeared to be located in a region of the intact native choriogonadotropin present at the surface of the hormone-receptor complex

Biodistribution of an anti-interleukin 2 receptor monoclonal antibody in rat recipients of a heart allograft, and its use as a rejection marker in gamma scintigraphy

International Nuclear Information System (INIS)

Thedrez, P.; Paineau, J.; Jacques, Y.; Chatal, J.F.; Pelegrin, A.; Bouchaud, C.; Soulillou, J.P.

1989-01-01

Anti-interleukin-2 receptor monoclonal antibodies have been shown to prevent allograft rejection. This paper reports on the biodistribution of a mouse MoAb directed at the 55 Kd alpha chain of rat interleukin-2 receptor (IL2-R) during allograft rejection. Only a low percentage (approximately 1%) of intact 125I-labeled MoAb was detected in the rejected graft, and irrelevant control IgG1 was found at a similar level. This suggests that most of the injected intact MoAb bound to graft tissue via its monomorphic Fc segment. In contrast, OX39 F(ab')2 fragments showed a preferential localization in the rejected allograft and did not bind to the LEW-to-LEW syngeneic heart graft. Irrelevant F(ab')2 did not concentrate in the allogeneic graft. Accordingly, F(ab')2 fragments from OX39 or irrelevant MoAb were used for gamma-scintigraphy on allograft recipients together with biodistribution studies. Results show that scintigraphy was able to detect allograft accumulation of 131I OX39 F(ab')2, whereas no imaging was obtained when OX39 F(ab')2 was used in the syngeneic combination or when irrelevant 131-IgG1 F(ab')2 was given to allograft recipients. This method, applied to the clinical situation, could be of interest for detection of early graft rejection episodes by immunoscintigraphy using reagents specific for activation determinants on lymphocyte membranes, such as anti-interleukin-2 receptor MoAb

Rapid Visualization of Human Tumor Xenografts through Optical Imaging with a Near-Infrared Fluorescent Anti–Epidermal Growth Factor Receptor Nanobody

Directory of Open Access Journals (Sweden)

Sabrina Oliveira

2012-01-01

Full Text Available Given that overexpression of the epidermal growth factor receptor (EGFR is found in many types of human epithelial cancers, noninvasive molecular imaging of this receptor is of great interest. A number of studies have employed monoclonal antibodies as probes; however, their characteristic long half-life in the bloodstream has encouraged the development of smaller probes. In this study, an anti-EGFR nanobody-based probe was developed and tested in comparison with cetuximab for application in optical molecular imaging. To this aim, the anti-EGFR nanobody 7D12 and cetuximab were conjugated to the near-infrared fluorophore IRDye800CW. 7D12-IR allowed the visualization of tumors as early as 30 minutes postinjection, whereas with cetuximab-IR, no signal above background was observed at the tumor site. Quantification of the IR-conjugated proteins in the tumors revealed ≈ 17% of injected dose per gram 2 hours after injection of 7D12-IR, which was significantly higher than the tumor uptake obtained 24 hours after injection of cetuximab-IR. This difference is associated with the superior penetration and distribution of 7D12-IR within the tumor. These results demonstrate that this anti-EGFR nanobody conjugated to the NIR fluorophore has excellent properties for rapid preclinical optical imaging, which holds promise for its future use as a complementary diagnostic tool in humans.

Monoclonal gammopathy: a diagnosis for to keep in mind; Gammapatia monoclonal: un diagnostico a tener en cuenta

Energy Technology Data Exchange (ETDEWEB)

Howland Alvarez, Ivon; Figueredo Peguero, Yrving; Luna Conde, Clara, E-mail: ihowlanda@infomed.sld.cu [Centro de Investigaciones Medico Quirurgicas, La Habana (Cuba); others, and

2011-07-01

How to identify monoclonal gammopathies at risk for progression has been studied for the last year. 40 patients were studied in which a monoclonal band had been detected, in some of the cases de novo. The electrophoresis was performed in the Hydrasys system. Of the total of electrophoresis carried out, the 14% was monoclonal gammopathy. In 36% a diagnostic assumption was not stated. Most frequent diagnosis in the group of patients with a diagnosis was multiple myeloma. Average age of patients was 61.5 years and there were differences among percentages for sex.

Microultrasound Molecular Imaging of Vascular Endothelial Growth Factor Receptor 2 in a Mouse Model of Tumor Angiogenesis

Directory of Open Access Journals (Sweden)

Joshua J. Rychak

2007-09-01

Full Text Available High-frequency microultrasound imaging of tumor progression in mice enables noninvasive anatomic and functional imaging at excellent spatial and temporal resolution, although microultrasonography alone does not offer molecular scale data. In the current study, we investigated the use of microbubble ultrasound contrast agents bearing targeting ligands specific for molecular markers of tumor angiogenesis using high-frequency microultrasound imaging. A xenograft tumor model in the mouse was used to image vascular endothelial growth factor receptor 2 (VEGFR-2 expression with microbubbles conjugated to an anti-VEGFR-2 monoclonal antibody or an isotype control. Microultrasound imaging was accomplished at a center frequency of 40 MHz, which provided lateral and axial resolutions of 40 and 90 μm, respectively. The B-mode (two-dimensional mode acoustic signal from microbubbles bound to the molecular target was determined by an ultrasound-based destruction-subtraction scheme. Quantification of the adherent microbubble fraction in nine tumor-bearing mice revealed significant retention of VEGFR-2-targeted microbubbles relative to control-targeted microbubbles. These data demonstrate that contrast-enhanced microultrasound imaging is a useful method for assessing molecular expression of tumor angiogenesis in mice at high resolution.

Oxygen dependency of epidermal growth factor receptor binding and DNA synthesis of rat hepatocytes

International Nuclear Information System (INIS)

Hirose, Tetsuro; Terajima, Hiroaki; Yamauchi, Akira

1997-01-01

Background/Aims: Changes in oxygen availability modulate replicative responses in several cell types, but the effects on hepatocyte replication remain unclear. We have studied the effects of transient nonlethal hypoxia on epidermal growth factor receptor binding and epidermal growth factor-induced DNA synthesis of rat hepatocytes. Methods: Lactate dehydrogenase activity in culture supernatant, intracellular adenosine triphosphate content, 125 I-epidermal growth factor specific binding, epidermal growth factor receptor protein expression, and 3 H-thymidine incorporation were compared between hepatocytes cultured in hypoxia and normoxia. Results: Hypoxia up to 3 h caused no significant increase in lactate dehydrogenase activity in the culture supernatant, while intracellular adenosine triphosphate content decreased time-dependently and was restored to normoxic levels by reoxygenation (nonlethal hypoxia). Concomitantly, 125 I-epidermal growth factor specific binding to hepatocytes decreased time-dependently (to 54.1% of normoxia) and was restored to control levels by reoxygenation, although 125 I-insulin specific binding was not affected. The decrease in 125 I-epidermal growth factor specific binding was explained by the decrease in the number or available epidermal growth factor receptors (21.37±3.08 to 12.16±1.42 fmol/10 5 cells), while the dissociation constant of the receptor was not affected. The change in the number of available receptors was not considered to be due to receptor degradation-resynthesis, since immuno-detection of the epidermal growth factor receptor revealed that the receptor protein expression did not change during hypoxia and reoxygenation, and since neither actinomycin D nor cycloheximide affected the recovery of 125 I-epidermal growth factor binding by reoxygenation. Inhibition of epidermal growth factor-induced DNA synthesis after hypoxia (to 75.4% of normoxia by 3 h hypoxia) paralleled the decrease in 125 I-epidermal growth factor binding

Tumor imaging with monoclonal antibodies

International Nuclear Information System (INIS)

Haisma, H.; Hilgers, J.

1987-01-01

Many monoclonal antibodies directed against tumor-associated antigens have been identified, but so far none of these are tumor specific. Polyclonal and monoclonal antibodies have been used for imaging of a wide variety of tumors with success. Radiolabeling of antibody is usually done with iodine isotopes of which 123 I is the best candidate for radioimmunodetection purposes. The labeling of antibodies through chelates makes it possible to use metal radioisotopes like 111 In, which is the best radioisotope for imaging with monoclonal antibodies due to its favorable half-life of 2.5 days. Usually imaging cannot be performed within 24 h after injection, but clearance of antibody can be increased by using F(ab) 2 of Fab. Another approach is to clear non-bound antibody by a second antibody, directed against the first. The detection limit of immunoimaging is about 2 cm, but will be improved by tomography or SPECT. There is still a high false positive and false negative rate, which makes it impossible to use radioimmunodetection as the only technique for diagnosis of tumors. In combination with other detection techniques, tumor imaging with monoclonal antibodies can improve diagnosis. 44 refs.; 3 tabs

A novel monoclonal antibody of human stem cell factor inhibits umbilical cord blood stem cell ex vivo expansion

Directory of Open Access Journals (Sweden)

Fan Jie

2012-12-01

Full Text Available Abstract Stem cell factor (SCF activates hematopoietic stem cell (HSC self-renewal and is being used to stimulate the ex vivo expansion of HSCs. The mechanism by which SCF supports expansion of HSCs remains poorly understood. In cord blood ex vivo expansion assays, a newly produced anti-SCF monoclonal antibody (clone 23C8 was found to significantly inhibit the expansion of CD34+ cells. This antibody appears to bind directly to a part of SCF that is critical for biological activity toward expansion of CD34+ cells, which is located in the first 104 amino acids from the NH2-terminus.

A monoclonal antibody for G protein-coupled receptor crystallography

DEFF Research Database (Denmark)

Day, Peter W; Rasmussen, Søren Gøgsig Faarup; Parnot, Charles

2007-01-01

G protein-coupled receptors (GPCRs) constitute the largest family of signaling proteins in mammals, mediating responses to hormones, neurotransmitters, and senses of sight, smell and taste. Mechanistic insight into GPCR signal transduction is limited by a paucity of high-resolution structural inf...

Production of Monoclonal Antibodies specific for Progesterone

OpenAIRE

YÜCEL, Fatıma

2014-01-01

Progesterone levels in milk and serum are indicators of pregnancy in cattle. The progesterone level reaches a peak on the 21 st and 22 nd days of pregnancy. Monoclonal antibodies specific to progesterone could be used for the immunodetection of milk and serum progesterone levels. We report here the development of hybrid cells prdoducing monoclonal antibodies specific for progesterone using hybridoma technology. Hybridoma cells secreting monoclonal antibodies against progesterone (MAM 2H1...

Combined use of anti-ErbB monoclonal antibodies and erlotinib enhances antibody-dependent cellular cytotoxicity of wild-type erlotinib-sensitive NSCLC cell lines

Directory of Open Access Journals (Sweden)

Cavazzoni Andrea

2012-12-01

Full Text Available Abstract Background The epidermal growth factor receptor (EGFR is an established target for anti-cancer treatment in different tumour types. Two different strategies have been explored to inhibit this pivotal molecule in epithelial cancer development: small molecules TKIs and monoclonal antibodies. ErbB/HER-targeting by monoclonal antibodies such as cetuximab and trastuzumab or tyrosine-kinase inhibitors as gefitinib or erlotinib has been proven effective in the treatment of advanced NSCLC. Results In this study we explored the potential of combining either erlotinib with cetuximab or trastuzumab to improve the efficacy of EGFR targeted therapy in EGFR wild-type NSCLC cell lines. Erlotinib treatment was observed to increase EGFR and/or HER2 expression at the plasma membrane level only in NSCLC cell lines sensitive to the drug inducing protein stabilization. The combined treatment had marginal effect on cell proliferation but markedly increased antibody-dependent, NK mediated, cytotoxicity in vitro. Moreover, in the Calu-3 xenograft model, the combination significantly inhibited tumour growth when compared with erlotinib and cetuximab alone. Conclusion Our results indicate that erlotinib increases surface expression of EGFR and/or HER2 only in EGFR-TKI sensitive NSCLC cell lines and, in turns, leads to increased susceptibility to ADCC both in vitro and in a xenograft models. The combination of erlotinib with monoclonal antibodies represents a potential strategy to improve the treatment of wild-type EGFR NSCLC patients sensitive to erlotinib.

Platelet-derived growth factor receptors in the human central nervous system : autoradiographic distribution and receptor densities in multiple sclerosis

NARCIS (Netherlands)

De Keyser, J; Wilczak, N

1997-01-01

Platelet derived growth factor (PDGF) receptors were studied in postmortem adult human brain and cervical spinal cord using autoradiography with human recombinant I-125-PDGF-BB. PDGF-BB binds to the three different dimers of PDGF receptors (alpha alpha, alpha beta and beta beta) PDGF receptors were

Induction and characterization of monoclonal anti-idiotypic antibodies reactive with idiotopes of canine parvovirus neutralizing monoclonal antibodies.

NARCIS (Netherlands)

G.F. Rimmelzwaan (Guus); J. van Es (Johan); G.A. Drost; F.G.C.M. Uytdehaag (Fons); A.D.M.E. Osterhaus (Albert)

1991-01-01

textabstractMonoclonal anti-idiotypic (anti-Id) antibodies (Ab2) were generated against idiotypes (Id) of canine parvovirus (CPV) specific monoclonal antibodies (MoAbs). The binding of most of these anti-Id antibodies to their corresponding Id could be inhibited by antigen, thus classifying these

Self-renewal of human embryonic stem cells requires insulin-like growth factor-1 receptor and ERBB2 receptor signaling

Science.gov (United States)

Wang, Linlin; Schulz, Thomas C.; Sherrer, Eric S.; Dauphin, Derek S.; Shin, Soojung; Nelson, Angelique M.; Ware, Carol B.; Zhan, Mei; Song, Chao-Zhong; Chen, Xiaoji; Brimble, Sandii N.; McLean, Amanda; Galeano, Maria J.; Uhl, Elizabeth W.; D'Amour, Kevin A.; Chesnut, Jonathan D.; Rao, Mahendra S.

2007-01-01

Despite progress in developing defined conditions for human embryonic stem cell (hESC) cultures, little is known about the cell-surface receptors that are activated under conditions supportive of hESC self-renewal. A simultaneous interrogation of 42 receptor tyrosine kinases (RTKs) in hESCs following stimulation with mouse embryonic fibroblast (MEF) conditioned medium (CM) revealed rapid and prominent tyrosine phosphorylation of insulin receptor (IR) and insulin-like growth factor-1 receptor (IGF1R); less prominent tyrosine phosphorylation of epidermal growth factor receptor (EGFR) family members, including ERBB2 and ERBB3; and trace phosphorylation of fibroblast growth factor receptors. Intense IGF1R and IR phosphorylation occurred in the absence of MEF conditioning (NCM) and was attributable to high concentrations of insulin in the proprietary KnockOut Serum Replacer (KSR). Inhibition of IGF1R using a blocking antibody or lentivirus-delivered shRNA reduced hESC self-renewal and promoted differentiation, while disruption of ERBB2 signaling with the selective inhibitor AG825 severely inhibited hESC proliferation and promoted apoptosis. A simple defined medium containing an IGF1 analog, heregulin-1β (a ligand for ERBB2/ERBB3), fibroblast growth factor-2 (FGF2), and activin A supported long-term growth of multiple hESC lines. These studies identify previously unappreciated RTKs that support hESC proliferation and self-renewal, and provide a rationally designed medium for the growth and maintenance of pluripotent hESCs. PMID:17761519

Epitope and functional specificity of monoclonal antibodies to mouse gamma interferon: the synthetic peptide approach

International Nuclear Information System (INIS)

Russell, J.K.; Hayes, M.P.; Carter, J.M.; Torres, B.A.; Dunn, B.M.; Johnson, H.M.

1986-01-01

Four anti-recombinant mouse gamma interferon (α-IFNγ) monoclonal antibodies were generated using hamster spleen cells. Binding of 125 I-IFNγ by these protein A-bound antibodies was specifically blocked by cold IFNγ. Binding by three of these antibodies was also blocked by a synthetic peptide corresponding to the N-terminal 1-39 amino acids of IFNγ, while a corresponding C-terminal (95-133) peptide had no effect on binding. One of the N-terminal specific monoclonal antibodies inhibited both the antiviral and macrophage priming (for tumor cell killing) activities of IFNγ, while the other two had no effect on either biological function. Blocking experiments with cold IFNγ and N-terminal peptide suggest that the epitope specificities of the monoclonal antibodies could be determined by the conformational or topographic structure of IFNγ. Polyclonal antibodies to either the N-terminal or C-terminal peptides also inhibited both the antiviral and macrophage priming activities of IFNγ. All of the antibodies that inhibited IFNγ function also blocked binding of IFNγ to membrane receptor on cells, while antibodies that did not inhibit function also did not block binding. The data suggest that both the N-terminal and C-terminal domains of IFNγ play an important role in its antiviral and macrophage priming functions, possibly in a cooperative manner

Characterization of a purified nicotinic receptor from rat brain by using idiotypic and anti-idiotypic antibodies

International Nuclear Information System (INIS)

Abood, L.G.; Langone, J.J.; Bjercke, R.; Lu, X.; Banerjee, S.

1987-01-01

The availability of an anti-nicotine monoclonal antibody has made it possible to further establish the nature of the nicotine recognition proteins purified from rat brain by affinity chromatography and to provide a highly sensitive assay for determining [ 3 H]nicotine binding to the purified material. An enantiomeric analogue of nicotine. (-)-6-hydroxymethylnicotine, was used to prepare the affinity column. In addition, with the use of an anti-idiotypic monoclonal antibody, it was confirmed that the recognition site for nicotine resides on a protein complex composed of two components with molecular masses of 62 and 57 kDa. It was also demonstrated that the same two proteins could be purified by immunoaffinity chromatography with the use of an anti-idiotypic monoclonal antibody. With the use of the anti-nicotine antibody to measure [ 3 H]nicotine binding, the purified material was shown to bind 250 pmol/mg of protein. By utilizing a procedure in which the purified receptor protein was conjugated to membranes by disulfide bonds, a binding activity of 80 pmol/mg was obtained. With the availability of sterospecific monoclonal antibodies to (-)-nicotine as well as monoclonal anti-idiotypic antibodies derived when the anti-nicotine antibodies were used as immunogens, additional procedures became available for the further characterization of the purified nicotine receptor and examining its (-)-[ 3 H]nicotine-binding characteristics

Individual and combining effects of anti-RANKL monoclonal antibody and teriparatide in ovariectomized mice

Directory of Open Access Journals (Sweden)

Naoto Tokuyama

2015-06-01

Full Text Available We examined the individual and combined effects of teriparatide and anti-RANKL (receptor activator of nuclear factor κB ligand monoclonal antibody in ovariectomized mice. Three-month-old female C57BL/6 mice were ovariectomized (OVX or sham operated. Four weeks after OVX, they were assigned to 3 different groups to receive anti-RANKL monoclonal antibody (Ab alone (5 mg/kg single injection at 4 weeks after OVX, Ab group, teriparatide alone (80 μg/kg daily injection for 4 weeks from 4 weeks after OVX, PTH group, or mAb plus teriparatide (Ab + PTH group. Mice were sacrificed 8 weeks after OVX. Bone mineral density (BMD was measured at the femur and lumbar spine. Hind limbs were subjected to histological and histomorphometric analysis. Serum osteocalcin and CTX-I levels were measured to investigate the bone turnover. Compared with Ab group, Ab + PTH group showed a significant increase in BMD at distal femur and femoral shaft. Cortical bone volume was significantly increased in PTH and Ab + PTH groups compared with Ab group. Bone turnover in Ab + PTH group was suppressed to the same degree as in Ab group. The number of TRAP-positive multinucleated cells was markedly reduced in Ab and Ab + PTH groups. These results suggest that combined treatment of teriparatide with anti-RANKL antibody has additive effects on BMD in OVX mice compared with individual treatment.

Tissue Distribution of a Therapeutic Monoclonal Antibody Determined by Large Pore Microdialysis.

Science.gov (United States)

Jadhav, Satyawan B; Khaowroongrueng, Vipada; Fueth, Matthias; Otteneder, Michael B; Richter, Wolfgang; Derendorf, Hartmut

2017-09-01

Therapeutic monoclonal antibodies (mAbs) exhibit limited distribution to the target tissues. Determination of target tissue interstitial concentration of mAbs is an important aspect in the assessment of their pharmacokinetic/pharmacodynamics relationship especially for mAbs targeting membrane bound receptors. The pharmacokinetics of R7072, a full length mAb (IgG) targeting human insulin-like growth factor-1 receptor was evaluated following a single intravenous dose at 1, 6.25, and 25 mg/kg in healthy female SCID-beige mice. R7072 showed linear pharmacokinetics over the dose range tested and was characterized by low systemic clearance and long terminal half-life. Furthermore, interstitial distribution of R7072 was evaluated in liver, skin, kidney, and muscle tissues using large pore microdialysis (MD) after intravenous administration of 10 mg/kg dose in mice. The relative recoveries of R7072 were consistent and similar between in vitro and in vivo MD experiments. The tissue and interstitial concentrations were significantly lower compared to serum concentrations and found to be highest in liver and lowest in muscle. The interstitial concentrations of R7072 were approximately 2-fold to 4-fold lower than corresponding total tissue concentrations. Large pore MD appears to be an attractive approach for direct measurement of pharmacologically relevant concentrations of therapeutic mAbs in tissue interstitial fluid. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Herceptin Enhances the Antitumor Effect of Natural Killer Cells on Breast Cancer Cells Expressing Human Epidermal Growth Factor Receptor-2

Directory of Open Access Journals (Sweden)

Xiao Tian

2017-10-01

Full Text Available Optimal adoptive cell therapy (ACT should contribute to effective cancer treatment. The unique ability of natural killer (NK cells to kill cancer cells independent of major histocompatibility requirement makes them suitable as ACT tools. Herceptin, an antihuman epidermal growth factor receptor-2 (anti-HER2 monoclonal antibody, is used to treat HER2+ breast cancer. However, it has limited effectiveness and possible severe cardiotoxicity. Given that Herceptin may increase the cytotoxicity of lymphocytes, we explored the possible augmentation of NK cell cytotoxicity against HER2+ breast cancer cells by Herceptin. We demonstrated that Herceptin could interact with CD16 on NK cells to expand the cytotoxic NK (specifically, CD56dim cell population. Additionally, Herceptin increased NK cell migration and cytotoxicity against HER2+ breast cancer cells. In a pilot study, Herceptin-treated NK cells shrunk lung nodular metastasis in a woman with HER2+ breast cancer who could not tolerate the cardiotoxic side effects of Herceptin. Our findings support the therapeutic potential of Herceptin-treated NK cells in patients with HER2+ and Herceptin-intolerant breast cancer.

Biologic effects of platelet-derived growth factor receptor α blockade in uterine cancer.

Science.gov (United States)

Roh, Ju-Won; Huang, Jie; Hu, Wei; Yang, XiaoYun; Jennings, Nicholas B; Sehgal, Vasudha; Sohn, Bo Hwa; Han, Hee Dong; Lee, Sun Joo; Thanapprapasr, Duangmani; Bottsford-Miller, Justin; Zand, Behrouz; Dalton, Heather J; Previs, Rebecca A; Davis, Ashley N; Matsuo, Koji; Lee, Ju-Seog; Ram, Prahlad; Coleman, Robert L; Sood, Anil K

2014-05-15

Platelet-derived growth factor receptor α (PDGFRα) expression is frequently observed in many kinds of cancer and is a candidate for therapeutic targeting. This preclinical study evaluated the biologic significance of PDGFRα and PDGFRα blockade (using a fully humanized monoclonal antibody, 3G3) in uterine cancer. Expression of PDGFRα was examined in uterine cancer clinical samples and cell lines, and biologic effects of PDGFRα inhibition were evaluated using in vitro (cell viability, apoptosis, and invasion) and in vivo (orthotopic) models of uterine cancer. PDGFRα was highly expressed and activated in uterine cancer samples and cell lines. Treatment with 3G3 resulted in substantial inhibition of PDGFRα phosphorylation and of downstream signaling molecules AKT and mitogen-activated protein kinase (MAPK). Cell viability and invasive potential of uterine cancer cells were also inhibited by 3G3 treatment. In orthotopic mouse models of uterine cancer, 3G3 monotherapy had significant antitumor effects in the PDGFRα-positive models (Hec-1A, Ishikawa, Spec-2) but not in the PDGFRα-negative model (OVCA432). Greater therapeutic effects were observed for 3G3 in combination with chemotherapy than for either drug alone in the PDGFRα-positive models. The antitumor effects of therapy were related to increased apoptosis and decreased proliferation and angiogenesis. These findings identify PDGFRα as an attractive target for therapeutic development in uterine cancer. ©2014 American Association for Cancer Research.

The CXCR4/SDF-1 chemokine receptor axis: a new target therapeutic for non-small cell lung cancer.

Science.gov (United States)

Otsuka, Shannon; Bebb, Gwyn

2008-12-01

Chemokines are proinflammatory chemoattractant cytokines that regulate cell trafficking and adhesion. The CXCR4 chemokine receptor and its ligand, stromal cell derived factor (SDF-1), constitute a chemokine/receptor axis that has attracted great interest because of an increasing understanding of its role in cancer, including lung cancer. The CXCR4/SDF-1 complex activates several pathways that mediate chemotaxis, migration and secretion of angiopoietic factors. Neutralization of SDF-1 by anti-SDF-1 or anti-CXCR4 monoclonal antibody in preclinical in vivo studies results in a significant decrease of non-small cell lung cancer metastases. Since anti-SDF-1/CXCR4 strategies have already been developed for use in combating human immunodeficiency virus infections, it is likely that these approaches will be used in clinical trials in non-small cell lung cancer in the very near future.

Inhibition of the release of soluble tumor necrosis factor receptors in experimental endotoxemia by an anti-tumor necrosis factor-alpha antibody

NARCIS (Netherlands)

Jansen, J.; van der Poll, T.; Levi, M. [=Marcel M.; ten Cate, H.; Gallati, H.; ten Cate, J. W.; van Deventer, S. J.

1995-01-01

The role of tumor necrosis factor-alpha in the shedding of soluble tumor necrosis factor receptors in endotoxemia was investigated. The appearance of the soluble tumor necrosis factor receptors was assessed in four healthy volunteers following an intravenous injection of tumor necrosis factor-alpha

Regulation of insulin-like growth factor I receptors on vascular smooth muscle cells by growth factors and phorbol esters.

Science.gov (United States)

Ververis, J J; Ku, L; Delafontaine, P

1993-06-01

Insulin-like growth factor I (IGF I) is an important mitogen for vascular smooth muscle cells. To characterize regulation of vascular IGF I receptors, we performed radioligand displacement experiments using rat aortic smooth muscle cells (RASMs). Serum deprivation for 48 hours caused a 40% decrease in IGF I receptor number. Exposure of quiescent RASMs to platelet-derived growth factor (PDGF), fibroblast growth factor (FGF), or angiotensin II (Ang II) caused a 1.5-2.0-fold increase in IGF I receptors per cell. After FGF exposure, there was a marked increase in the mitogenic response to IGF I. IGF I downregulated its receptors in the presence of platelet-poor plasma. Stimulation of protein kinase C (PKC) by exposure of quiescent RASMs to phorbol 12-myristate 13-acetate caused a biphasic response in IGF I binding; there was a 42% decrease in receptor number at 45 minutes and a 238% increase at 24 hours. To determine the role of PKC in growth factor-induced regulation of IGF I receptors, we downregulated PKC by exposing RASMs to phorbol 12,13-dibutyrate (PDBu) for 48 hours. PDGF- and FGF- but not Ang II-mediated upregulation of IGF I receptors was completely inhibited in PDBu-treated cells. Thus, acute PKC activation by phorbol esters inhibits IGF I binding, whereas chronic PKC activation increases IGF I binding. PDGF and FGF but not Ang II regulate vascular IGF I receptors through a PKC-dependent pathway. These data provide new insights into the regulation of vascular smooth muscle cell IGF I receptors in vitro and are of potential importance in characterizing vascular proliferative responses in vivo.

Epidermal Growth Factor Receptor in Pancreatic Cancer

International Nuclear Information System (INIS)

Oliveira-Cunha, Melissa; Newman, William G.; Siriwardena, Ajith K.

2011-01-01

Pancreatic cancer is the fourth leading cause of cancer related death. The difficulty in detecting pancreatic cancer at an early stage, aggressiveness and the lack of effective therapy all contribute to the high mortality. Epidermal growth factor receptor (EGFR) is a transmembrane glycoprotein, which is expressed in normal human tissues. It is a member of the tyrosine kinase family of growth factors receptors and is encoded by proto-oncogenes. Several studies have demonstrated that EGFR is over-expressed in pancreatic cancer. Over-expression correlates with more advanced disease, poor survival and the presence of metastases. Therefore, inhibition of the EGFR signaling pathway is an attractive therapeutic target. Although several combinations of EGFR inhibitors with chemotherapy demonstrate inhibition of tumor-induced angiogenesis, tumor cell apoptosis and regression in xenograft models, these benefits remain to be confirmed. Multimodality treatment incorporating EGFR-inhibition is emerging as a novel strategy in the treatment of pancreatic cancer

Radiolabeled monoclonal antibodies: a review

International Nuclear Information System (INIS)

Toledo e Souza, I.T. de; Okada, H.

1990-05-01

Since the description by Kohler and Milstein 1975 of their technique for producing monoclonal antibodies of predefined specificity, it has become a mainstay in most laboratories that utilize immunochemical techniques to study problems in basic, applied or clinical research. Paradoxically, the very success of monoclonal antibodies has generated a literature which is now so vast and scattered that it has become difficult to obtain a perspective. This brief review represents the distillation of many publications relating to the production and use of monoclonaal antibodies as radiopharmaceuticals. Significant advances were made possible in the last few years by combined developments in the fields of tumor-associated antigens and of monoclonal antibodies. In fact monoclonal antibodies against some well defined tumor-associated antigens, has led to significantly greater practical possibilities for producing highly specific radiolabeled antibodies as radiopharmaceuticals for diagnosis and therapy of human tumors. One of the main requirements of this methodology is the availability of stable radiopharmaceutical reagents which after labeling in vivo injection retain the capacity of specific interaction with the defined antigen and their molecular integrity. Since injection into human is the objetive of this kind of study all the specifications of radiopharmaceutical have to be fulfilled e.g. sterility, apirogenicity and absence of toxicity. (author) [pt

The Pseudo signal peptide of the corticotropin-releasing factor receptor type 2A prevents receptor oligomerization.

Science.gov (United States)

Teichmann, Anke; Rutz, Claudia; Kreuchwig, Annika; Krause, Gerd; Wiesner, Burkhard; Schülein, Ralf

2012-08-03

N-terminal signal peptides mediate the interaction of native proteins with the translocon complex of the endoplasmic reticulum membrane and are cleaved off during early protein biogenesis. The corticotropin-releasing factor receptor type 2a (CRF(2(a))R) possesses an N-terminal pseudo signal peptide, which represents a so far unique domain within the large protein family of G protein-coupled receptors (GPCRs). In contrast to a conventional signal peptide, the pseudo signal peptide remains uncleaved and consequently forms a hydrophobic extension at the N terminus of the receptor. The functional consequence of the presence of the pseudo signal peptide is not understood. Here, we have analyzed the significance of this domain for receptor dimerization/oligomerization in detail. To this end, we took the CRF(2(a))R and the homologous corticotropin-releasing factor receptor type 1 (CRF(1)R) possessing a conventional cleaved signal peptide and conducted signal peptide exchange experiments. Using single cell and single molecule imaging methods (fluorescence resonance energy transfer and fluorescence cross-correlation spectroscopy, respectively) as well as biochemical experiments, we obtained two novel findings; we could show that (i) the CRF(2(a))R is expressed exclusively as a monomer, and (ii) the presence of the pseudo signal peptide prevents its oligomerization. Thus, we have identified a novel functional domain within the GPCR protein family, which plays a role in receptor oligomerization and which may be useful to study the functional significance of this process in general.

Mechanisms of integrin-vascular endothelial growth factor receptor cross-activation in angiogenesis.

Science.gov (United States)

Mahabeleshwar, Ganapati H; Feng, Weiyi; Reddy, Kumar; Plow, Edward F; Byzova, Tatiana V

2007-09-14

The functional responses of endothelial cells are dependent on signaling from peptide growth factors and the cellular adhesion receptors, integrins. These include cell adhesion, migration, and proliferation, which, in turn, are essential for more complex processes such as formation of the endothelial tube network during angiogenesis. This study identifies the molecular requirements for the cross-activation between beta3 integrin and tyrosine kinase receptor 2 for vascular endothelial growth factor (VEGF) receptor (VEGFR-2) on endothelium. The relationship between VEGFR-2 and beta3 integrin appears to be synergistic, because VEGFR-2 activation induces beta3 integrin tyrosine phosphorylation, which, in turn, is crucial for VEGF-induced tyrosine phosphorylation of VEGFR-2. We demonstrate here that adhesion- and growth factor-induced beta3 integrin tyrosine phosphorylation are directly mediated by c-Src. VEGF-stimulated recruitment and activation of c-Src and subsequent beta3 integrin tyrosine phosphorylation are critical for interaction between VEGFR-2 and beta3 integrin. Moreover, c-Src mediates growth factor-induced beta3 integrin activation, ligand binding, beta3 integrin-dependent cell adhesion, directional migration of endothelial cells, and initiation of angiogenic programming in endothelial cells. Thus, the present study determines the molecular mechanisms and consequences of the synergism between 2 cell surface receptor systems, growth factor receptor and integrins, and opens new avenues for the development of pro- and antiangiogenic strategies.

The evolving role of monoclonal antibodies in colorectal cancer: early presumptions and impact on clinical trial development.

Science.gov (United States)

Eng, Cathy

2010-01-01

Targeted biologic agents have an established role in treating metastatic colorectal cancer (mCRC). Bevacizumab, a recombinant monoclonal antibody against the vascular endothelial growth factor ligand is approved by the U.S. Food and Drug Administration (FDA) for bevacizumab-naïve patients. Cetuximab, a chimeric monoclonal antibody (mAb) against the epidermal growth factor receptor (EGFR) is FDA approved as a single agent, or in combination with irinotecan, in both irinotecan-naïve and refractory patients, and has additional efficacy in combination with oxaliplatin. Panitumumab, a fully human EGFR mAb, is FDA approved as a single agent in refractory patients but has additional efficacy in combination with chemotherapy. After reaching a temporary therapeutic plateau of FDA-approved agents for the treatment of mCRC, pivotal results have developed that critically affect the care for these patients. Correlative data from randomized trials of EGFR inhibitors across disease settings have demonstrated higher response rates, specifically for patients with wild-type K-RAS tumors. The interpretation of the B-RAF mutation and other molecular markers may further define the appropriateness of anti-EGFR therapy. Recent literature revealed that the first-line use of combined anti-EGFR therapy plus bevacizumab resulted in inferior outcomes and additional toxicities. Furthermore, the role of biologic agents for locally advanced colon cancer cannot be advocated at this time. With impending changes in the health care system, the economic impact of mAbs will continue to be scrutinized. Hence, as the significance of molecular markers continues to develop, their role as it pertains to the appropriate use of biologic agents in the treatment of mCRC will continue to evolve.

[3H]Azidodantrolene photoaffinity labeling, synthetic domain peptides and monoclonal antibody reactivity identify the dantrolene binding sequence on RyR1

Energy Technology Data Exchange (ETDEWEB)

Paul-Pletzer, Kalanethee; Yamamoto, Takeshi; Bhat, Manju B.; Ma, Jianjie; Ikemoto, Noriaki; Jimenez, Leslie S.; Morimoto, Hiromi; Williams, Philip G.; Parness, Jerome

2002-06-14

Dantrolene is a drug that suppresses intracellular Ca2+ release from sarcoplasmic reticulum in normal skeletal muscle and is used as a therapeutic agent in individuals susceptible to malignant hyperthermia. Though its precise mechanism of action has not been elucidated, we have identified the N-terminal region (amino acids 1-1400) of the skeletal muscle isoform of the ryanodine receptor (RyR1), the primary Ca2+ release channel in sarcoplasmic reticulum, as a molecular target for dantrolene using the photoaffinity analog [3H]azidodantrolene(1). Here, we demonstrate that heterologously expressed RyR1 retains its capacity to be specifically labeled with [3H]azidodantrolene,indicating that muscle specific factors are not required for this ligand-receptor interaction. Synthetic domain peptides of RyR1, previously shown to affect RyR1 function in vitro and in vivo, were exploited as potential drug binding site mimics and used in photoaffinity labeling experiments. Only DP1 and DP1-2, peptide s containing the amino acid sequence corresponding to RyR1 residues 590-609, were specifically labeled by [3H]azidodantrolene. A monoclonal anti-RyR1 antibody which recognizes RyR1 and its 1400 amino acid N-terminal fragment, recognizes DP1 and DP1-2 in both Western blots and immunoprecipitation assays, and specifically inhibits [3H]azidodantrolene photolabeling of RyR1 and its N-terminal fragment in sarcoplasmic reticulum. Our results indicate that synthetic domain peptides can mimic a native, ligand binding conformation in vitro, and that the dantrolene binding site and the epitope for the monoclonal antibody on RyR1 are equivalent and composed of amino-acids 590-609.

Population PK and IgE pharmacodynamic analysis of a fully human monoclonal antibody against IL4 receptor.

Science.gov (United States)

Kakkar, Tarundeep; Sung, Cynthia; Gibiansky, Leonid; Vu, Thuy; Narayanan, Adimoolam; Lin, Shao-Lee; Vincent, Michael; Banfield, Christopher; Colbert, Alex; Hoofring, Sarah; Starcevic, Marta; Ma, Peiming

2011-10-01

For AMG 317, a fully human monoclonal antibody to interleukin receptor IL-4Rα, we developed a population pharmacokinetic (PK) model by fitting data from four early phase clinical trials of intravenous and subcutaneous (SC) routes simultaneously, investigated important PK covariates, and explored the relationship between exposure and IgE response. Data for 294 subjects and 2183 AMG 317 plasma concentrations from three Phase 1 and 1 Phase 2 studies were analyzed by nonlinear mixed effects modeling using first-order conditional estimation with interaction. The relationship of IgE response with post hoc estimates of exposure generated from the final PK model was explored based on data from asthmatic patients. The best structural model was a two-compartment quasi-steady-state target-mediated drug disposition model with linear and non-linear clearances. For a typical 80-kg, 40-year subject, linear clearance was 35.0 mL/hr, central and peripheral volumes of distribution were 1.78 and 5.03 L, respectively, and SC bioavailability was 24.3%. Body weight was an important covariate on linear clearance and central volume; age influenced absorption rate. A significant treatment effect was observable between the cumulative AUC and IgE response measured. The population PK model adequately described AMG 317 PK from IV and SC routes over a 60-fold range of doses with two dosing strengths across multiple studies covering healthy volunteers and patients with mild to severe asthma. IgE response across a range of doses and over the sampling time points was found to be related to cumulative AMG 317 exposure.

Cognitive disorder and changes in cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor following brain injury

Institute of Scientific and Technical Information of China (English)

Weiliang Zhao; Dezhi Kang; Yuanxiang Lin

2008-01-01

BACKGROUND: Learning and memory damage is one of the most permanent and the severest symptoms of traumatic brain injury; it can seriously influence the normal life and work of patients. Some research has demonstrated that cognitive disorder is closely related to nicotine cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor. OBJECTIVE: To summarize the cognitive disorder and changes in nicotine cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor following brain injury. RETRIEVAL STRATEGY: A computer-based online search was conducted in PUBMED for English language publications containing the key words "brain injured, cognitive handicap, acetylcholine, N-methyl-D aspartate receptors, neural cell adhesion molecule, brain-derived neurotrophic factor" from January 2000 to December 2007. There were 44 papers in total. Inclusion criteria: ① articles about changes in nicotine cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor following brain injury; ② articles in the same researching circle published in authoritative journals or recently published. Exclusion criteria: duplicated articles.LITERATURE EVALUATION: References were mainly derived from research on changes in these four factors following brain injury. The 20 included papers were clinical or basic experimental studies. DATA SYNTHESIS: After craniocerebral injury, changes in these four factors in brain were similar to those during recovery from cognitive disorder, to a certain degree. Some data have indicated that activation of nicotine cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor could greatly improve cognitive disorder following brain injury. However, there are still a lot of questions remaining; for example, how do these

A chimeric antigen receptor for TRAIL-receptor 1 induces apoptosis in various types of tumor cells.

Science.gov (United States)

Kobayashi, Eiji; Kishi, Hiroyuki; Ozawa, Tatsuhiko; Hamana, Hiroshi; Nakagawa, Hidetoshi; Jin, Aishun; Lin, Zhezhu; Muraguchi, Atsushi

2014-10-31

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) and its associated receptors (TRAIL-R/TR) are attractive targets for cancer therapy because TRAIL induces apoptosis in tumor cells through TR while having little cytotoxicity on normal cells. Therefore, many agonistic monoclonal antibodies (mAbs) specific for TR have been produced, and these induce apoptosis in multiple tumor cell types. However, some TR-expressing tumor cells are resistant to TR-specific mAb-induced apoptosis. In this study, we constructed a chimeric antigen receptor (CAR) of a TRAIL-receptor 1 (TR1)-specific single chain variable fragment (scFv) antibody (TR1-scFv-CAR) and expressed it on a Jurkat T cell line, the KHYG-1 NK cell line, and human peripheral blood lymphocytes (PBLs). We found that the TR1-scFv-CAR-expressing Jurkat cells killed target cells via TR1-mediated apoptosis, whereas TR1-scFv-CAR-expressing KHYG-1 cells and PBLs killed target cells not only via TR1-mediated apoptosis but also via CAR signal-induced cytolysis, resulting in cytotoxicity on a broader range if target cells than with TR1-scFv-CAR-expressing Jurkat cells. The results suggest that TR1-scFv-CAR could be a new candidate for cancer gene therapy. Copyright © 2014 Elsevier Inc. All rights reserved.

Topical administration of adrenergic receptor pharmaceutics and nerve growth factor

Directory of Open Access Journals (Sweden)

Jena J Steinle

2010-06-01

Full Text Available Jena J SteinleDepartments of Ophthalmology and Anatomy and Neurobiology, Hamilton Eye Institute, University of Tennessee Health Science Center, Memphis, TN 38163, USAAbstract: Topical application of nerve growth factor (NGF and adrenergic receptor pharmaceutics are currently in use for corneal ulcers and glaucoma. A recent interest in the neuroprotective abilities of NGF has led to a renewed interest in NGF as a therapeutic for retinal and choroidal diseases. NGF can promote cell proliferation through actions of the TrkA receptor or promote apoptosis through receptor p75NTR. This understanding has led to novel interest in the role of NGF for diseases of the posterior eye. The role of β-adrenergic receptor agonists and antagonists for treatments of glaucoma, diabetic retinopathy, and their potential mechanisms of action, are still under investigation. This review discusses the current knowledge and applications of topical NGF and adrenergic receptor drugs for ocular disease.Keywords: NGF, β-adrenergic receptor agents, α-adrenergic receptor agents, retina, cornea, glaucoma

Preclinical Evaluation of (177)Lu-Nimotuzumab: A Potential Tool for Radioimmunotherapy of Epidermal Growth Factor Receptor-Overexpressing Tumors

Czech Academy of Sciences Publication Activity Database

Beckford, Denis R.; Eigner, Sebastian; Beran, Miloš; Eigner-Henke, Kateřina; Lázníček, M.; Melichar, František; Chinol, M.

2011-01-01

Roč. 26, č. 3 (2011), s. 287-297 ISSN 1084-9785 R&D Projects: GA MŠk OE08018 Institutional research plan: CEZ:AV0Z10480505 Keywords : EGFR * (177)Lu * monoclonal antibodies * Nimotuzumab Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 1.787, year: 2011

Binding of alpha-fetoprotein by immobilized monoclonal antibodies during episodes of zero-gravity obtained by parabolic flight

Science.gov (United States)

Spooner, Brian S.; Guikema, James A.; Barnes, Grady

1990-01-01

Alpha-fetoprotein (AFP), a single-chain polypeptide which is synthesized by the liver and yolk sac of the human fetus, provided a model ligand for assessing the effects of microgravity on ligand binding to surface-immobilized model receptor molecules. Monoclonal antibodies, used as receptors for AFP, were immobilized by covalent attachment to latex microparticles. Zero gravity environment was obtained by parabolic flight aboard NASA 930, a modified KC-135 aircraft. Buring the onset of an episode of zero gravity, ligand and receptor were mixed. Timed incubation (20 s) was terminated by centrifugation, the supernatant removed, and microparticies were assessed for bound AFP by immunochemical methods. The extent of binding was not influenced by microgravity, when compared with 1-G controls, which suggests that aberrant cellular activities observed in microgravity are not the simple expression of altered macromolecular interactions.

Monoclonal antibody FsC-47 against carp sperm creatine kinase

Czech Academy of Sciences Publication Activity Database

Koubek, Pavel; Elzeinová, Fatima; Šulc, Miroslav; Linhart, O.; Pěknicová, Jana

2006-01-01

Roč. 25, č. 3 (2006), s. 154-157 ISSN 1554-0014 R&D Projects: GA ČR(CZ) GA524/03/0178 Institutional research plan: CEZ:AV0Z50520514; CEZ:AV0Z50200510 Keywords : creatin kinase * monoclonal antibody * carp sperm Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.411, year: 2006

Targeting of the tumor necrosis factor receptor superfamily for cancer immunotherapy

NARCIS (Netherlands)

Bremer, Edwin

2013-01-01

The tumor necrosis factor (TNF) ligand and cognate TNF receptor superfamilies constitute an important regulatory axis that is pivotal for immune homeostasis and correct execution of immune responses. TNF ligands and receptors are involved in diverse biological processes ranging from the selective

Generation of a Monoclonal Antibody against Mycoplasma spp. following Accidental Contamination during Production of a Monoclonal Antibody against Lawsonia intracellularis

OpenAIRE

Hwang, Jeong-Min; Lee, Ji-Hye; Yeh, Jung-Yong

2012-01-01

This report describes Mycoplasma contamination of Lawsonia intracellularis cultures that led to the unintended acquisition of a monoclonal antibody against Mycoplasma spp. during the attempted generation of a monoclonal antibody against L. intracellularis.

Increase of tumor necrosis factor receptor 1 expression in women with unexplained early spontaneous abortion

Institute of Scientific and Technical Information of China (English)

YAN Chun-fang; YU Xue-wen; JIN Hui; LI Xu

2004-01-01

To investigate membrane tumor necrosis factor receptor 1 protein expression level in decidua andconcentration of soluble tumor necrosis factor receptor 1 in serum in women with unexplained early spontaneous abortion,threatened abortion, and compare the levels with healthy pregnant women. Methods: Thirty-seven women with unexplainedearly spontaneous abortion, 27 women with threatened abortion, and 34 healthy pregnant women undergoing artificial abortionof pregnancy at 6 - 10 weeks of gestation were selected. Decidual samples were collected when women were undergoing arti-ficial abortion, and blood samples were collected at the same time. The level of membrane tumor necrosis factor receptor 1 indecidua was detected by flow cytometer, and the concentration of soluble tumor necrosis factor receptor 1 in sera was mea-sured with an enzyme-linked immunosorbent assay. Results: The ercentages of membrane tumor necrosis factor receptor 1positive decidual cells were 16.42 ± 7.10 Mean ± SD for women with unexplained early spontaneous abortion and 13.14 ±6.30 for healthy pregnant women ( P ＜ 0.05). Serum oncentration of soluble tumor necrosis factor receptor 1 was signifi-cantly higher in women with unexplained early spontaneous abortion than in healthy pregnant women and in women withthreatened abortion, and no difference was found between healthy pregnant women and women with threatened abortion.Conclusion: Women with unexplained early spontaneous abortion present significantly higher expression of tumor necrosisfactor receptor 1 than healthy pregnant women, suggesting that over-expression of tumor necrosis factor receptor 1 may cont-ribute to the development of early spontaneous abortion.

GLP-1 receptor localization in monkey and human tissue

DEFF Research Database (Denmark)

Pyke, Charles; Heller, R Scott; Kirk, Rikke K

2014-01-01

and increase heart rate. Using a new monoclonal antibody for immunohistochemistry, we detected GLP-1 receptor (GLP-1R) in important target organs in humans and monkeys. In the pancreas, GLP-1R was predominantly localized in β-cells with a markedly weaker expression in acinar cells. Pancreatic ductal epithelial...

Anti-idiotypic antibody: A new strategy for the development of a growth hormone receptor antagonist.

Science.gov (United States)

Lan, Hainan; Zheng, Xin; Khan, Muhammad Akram; Li, Steven

2015-11-01

In general, traditional growth hormone receptor antagonist can be divided into two major classes: growth hormone (GH) analogues and anti-growth hormone receptor (GHR) antibodies. Herein, we tried to explore a new class of growth hormone receptor (GHR) antagonist that may have potential advantages over the traditional antagonists. For this, we developed a monoclonal anti-idiotypic antibody growth hormone, termed CG-86. A series of experiments were conducted to characterize and evaluate this antibody, and the results from a competitive receptor-binding assay, Enzyme Linked Immunosorbent Assays (ELISA) and epitope mapping demonstrate that CG-86 behaved as a typical Ab2β. Next, we examined its antagonistic activity using in vitro cell models, and the results showed that CG-86 could effectively inhibit growth hormone receptor-mediated signalling and effectively inhibit growth hormone-induced Ba/F3-GHR638 proliferation. In summary, these studies show that an anti-idiotypic antibody (CG-86) has promise as a novel growth hormone receptor antagonist. Furthermore, the current findings also suggest that anti-idiotypic antibody may represent a novel strategy to produce a new class of growth hormone receptor antagonist, and this strategy may be applied with other cytokines or growth factors. Copyright © 2015 Elsevier Ltd. All rights reserved.

Novel targeted approaches to treating biliary tract cancer: the dual epidermal growth factor receptor and ErbB-2 tyrosine kinase inhibitor NVP-AEE788 is more efficient than the epidermal growth factor receptor inhibitors gefitinib and erlotinib.

Science.gov (United States)

Wiedmann, Marcus; Feisthammel, Jürgen; Blüthner, Thilo; Tannapfel, Andrea; Kamenz, Thomas; Kluge, Annett; Mössner, Joachim; Caca, Karel

2006-08-01

Aberrant activation of the epidermal growth factor receptor is frequently observed in neoplasia, notably in tumors of epithelial origin. Attempts to treat such tumors with epidermal growth factor receptor antagonists resulted in remarkable success in recent studies. Little is known, however, about the efficacy of this therapy in biliary tract cancer. Protein expression of epidermal growth factor receptor, ErbB-2, and vascular endothelial growth factor receptor-2 was assessed in seven human biliary tract cancer cell lines by immunoblotting. In addition, histological sections from 19 patients with extrahepatic cholangiocarcinoma were analyzed for epidermal growth factor receptor, ErbB-2 and vascular endothelial growth factor receptor-2 expression by immunohistochemistry. Moreover, we sequenced the cDNA products representing the entire epidermal growth factor receptor coding region of the seven cell lines, and searched for genomic epidermal growth factor receptor amplifications and polysomy by fluorescence in-situ hybridization. Cell growth inhibition by gefitinib erlotinib and NVP-AEE788 was studied in vitro by automated cell counting. In addition, the anti-tumoral effect of erlotinib and NVP-AEE788 was studied in a chimeric mouse model. The anti-tumoral drug mechanism in this model was assessed by MIB-1 antibody staining, terminal deoxynucleotidyl transfer-mediated dUTP nick end-labelling assay, von Willebrand factor staining, and immunoblotting for p-p42/44 (p-Erk1/2, p-MAPK) and p-AKT. Immunoblotting revealed expression of epidermal growth factor receptor, ErbB-2, and vascular endothelial growth factor receptor-2 in all biliary tract cancer cell lines. EGFR was detectable in six of 19 (32%) extrahepatic human cholangiocarcinoma tissue samples, ErbB-2 in 16 of 19 (84%), and vascular endothelial growth factor receptor-2 in nine of 19 (47%). Neither epidermal growth factor receptor mutations nor amplifications or polysomy were found in the seven biliary tract cancer

Epidermal growth factor receptor expression in urinary bladder cancer

Directory of Open Access Journals (Sweden)

Dayalu S.L. Naik

2011-01-01

Full Text Available Objective : To evaluate the expression pattern of epidermal growth factor receptor (EGFR in urinary bladder cancer and its association with human epidermal growth factor receptor 2 (HER2, epidermal growth factor (EGF, interleukin-6 (IL-6, and high risk human papilloma virus (HPV types 16 and 18. Materials and Methods : Thirty cases of urothelial carcinoma were analyzed. EGFR, HER2, EGF, and IL-6 expressions in the tissue were evaluated by immunohistochemical staining. For HPV, DNA from tissue samples was extracted and detection of HPV was done by PCR technique. Furthermore, evaluation of different intracellular molecules associated with EGFR signaling pathways was performed by the western blot method using lysates from various cells and tissues. Results : In this study, the frequencies of immunopositivity for EGFR, HER2, EGF, and IL-6 were 23%, 60%, 47%, and 80%, respectively. No cases were positive for HPV-18, whereas HPV-16 was detected in 10% cases. Overall, expression of EGFR did not show any statistically significant association with the studied parameters. However, among male patients, a significant association was found only between EGFR and HER2. Conclusions : Overexpression of EGFR and/or HER2, two important members of the same family of growth factor receptors, was observed in a considerable proportion of cases. Precise knowledge in this subject would be helpful to formulate a rational treatment strategy in patients with urinary bladder cancer.

LIPOPOLYSACCHARIDE INDUCES THE PRODUCTION OF DIAGNOSTIC MONOCLONAL ANTIBODY BY HYBRIDOMA CELLS AGAINST CONGENITAL ADRENAL HYPERPLASIA

Directory of Open Access Journals (Sweden)

GEK KEE CHUA

2017-11-01

Full Text Available The purpose of this research is to screen and identify the potential inducers in maximizing the production of monoclonal antibody by hybridoma 192 cell line for Congenital Adrenal Hyperplasia diagnostic. There are nine inducers used in this research, namely lysozyme, aldolase, sodium butyrate, sodium phosphate, potassium phosphate, dimethyl sulfoxide, lipopolysaccharide, essential amino acids, and nonessential amino acids. Hybridoma 192 cell was cultured in 5% CO2 incubator at 37°C and ˃80% humidity in the medium with different concentrations of inducer agents. The inducers were added at the beginning of the culture and the samples were taken after 72 h of culture. The performance of these inducer agents was assessed based on the maximum monoclonal antibody titer achieved using Enzyme-linked Immunosorbent Assay. Lipopolysaccharide was found to increase the maximum monoclonal antibody titer when supplemented at 8 to 12 µg/mL. After optimization using one-factor central composite design at this range, the optimum point was determined to be 8 µg/mL. Verification experiments shows that lipopolysaccharide enhanced the average specific monoclonal antibody production rate by 56% relative to control. In conclusion, lipopolysaccharide at 8 µg/mL is able to increase the monoclonal antibody specific production of hybridoma 192 cell line.

Andrographolide regulates epidermal growth factor receptor and transferrin receptor trafficking in epidermoid carcinoma (A-431) cells

Science.gov (United States)

Tan, Y; Chiow, KH; Huang, D; Wong, SH

2010-01-01

Background and purpose: Andrographolide is the active component of Andrographis paniculata, a plant used in both Indian and Chinese traditional medicine, and it has been demonstrated to induce apoptosis in different cancer cell lines. However, not much is known about how it may affect the key receptors implicated in cancer. Knowledge of how andrographolide affects receptor trafficking will allow us to better understand new mechanisms by which andrographolide may cause death in cancer cells. Experimental approach: We utilized the well-characterized epidermal growth factor receptor (EGFR) and transferrin receptor (TfR) expressed in epidermoid carcinoma (A-431) cells as a model to study the effect of andrographolide on receptor trafficking. Receptor distribution, the total number of receptors and surface receptors were analysed by immunofluorescence, Western blot as well as flow-cytometry respectively. Key results: Andrographolide treatment inhibited cell growth, down-regulated EGFRs on the cell surface and affected the degradation of EGFRs and TfRs. The EGFR was internalized into the cell at an increased rate, and accumulated in a compartment that co-localizes with the lysosomal-associated membrane protein in the late endosomes. Conclusion and implications: This study sheds light on how andrographolide may affect receptor trafficking by inhibiting receptor movement from the late endosomes to lysosomes. The down-regulation of EGFR from the cell surface also indicates a new mechanism by which andrographolide may induce cancer cell death. PMID:20233216

Monoclonal antibodies based on hybridoma technology.

Science.gov (United States)

Yagami, Hisanori; Kato, Hiroshi; Tsumoto, Kanta; Tomita, Masahiro

2013-03-01

Based on the size and scope of the present global market for medicine, monoclonal antibodies (mAbs) have a very promising future, with applications for cancers through autoimmune ailments to infectious disease. Since mAbs recognize only their target antigens and not other unrelated proteins, pinpoint medical treatment is possible. Global demand is dramatically expanding. Hybridoma technology, which allows production of mAbs directed against antigens of interest is therefore privileged. However, there are some pivotal points for further development to generate therapeutic antibodies. One is selective generation of human mAbs. Employment of transgenic mice producing human antibodies would overcome this problem. Another focus is recognition sites and conformational epitopes in antigens may be just as important as linear epitopes, especially when membrane proteins such as receptors are targeted. Recognition of intact structures is of critical importance for medical purposes. In this review, we describe patent related information for therapeutic mAbs based on hybridoma technology and also discuss new advances in hybridoma technology that facilitate selective production of stereospecific mAbs.

Tumor necrosis factor receptor- associated factor 6 (TRAF6) regulation of development, function, and homeostasis of the immune system.

Science.gov (United States)

Walsh, Matthew C; Lee, JangEun; Choi, Yongwon

2015-07-01

Tumor necrosis factor receptor (TNFR)-associated factor 6 (TRAF6) is an adapter protein that mediates a wide array of protein-protein interactions via its TRAF domain and a RING finger domain that possesses non-conventional E3 ubiquitin ligase activity. First identified nearly two decades ago as a mediator of interleukin-1 receptor (IL-1R)-mediated activation of NFκB, TRAF6 has since been identified as an actor downstream of multiple receptor families with immunoregulatory functions, including members of the TNFR superfamily, the Toll-like receptor (TLR) family, tumor growth factor-β receptors (TGFβR), and T-cell receptor (TCR). In addition to NFκB, TRAF6 may also direct activation of mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K), and interferon regulatory factor pathways. In the context of the immune system, TRAF6-mediated signals have proven critical for the development, homeostasis, and/or activation of B cells, T cells, and myeloid cells, including macrophages, dendritic cells, and osteoclasts, as well as for organogenesis of thymic and secondary lymphoid tissues. In multiple cellular contexts, TRAF6 function is essential not only for proper activation of the immune system but also for maintaining immune tolerance, and more recent work has begun to identify mechanisms of contextual specificity for TRAF6, involving both regulatory protein interactions, and messenger RNA regulation by microRNAs. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Tumor necrosis factor receptor associated factor 6 (TRAF6) regulation of development, function, and homeostasis of the immune system

Science.gov (United States)

Walsh, Matthew C.; Lee, JangEun; Choi, Yongwon

2016-01-01

Summary Tumor necrosis factor receptor (TNFR)-associated factor 6 (TRAF6) is an adaptor protein that mediates a wide array of protein-protein interactions via its TRAF domain and a RING finger domain that possesses non-conventional E3 ubiquitin ligase activity. First identified nearly two decades ago as a mediator of IL-1 receptor (IL-1R)-mediated activation of NFκB, TRAF6 has since been identified as an actor downstream of multiple receptor families with immunoregulatory functions, including members of the TNFR superfamily, the toll-like receptor (TLR) family, tumor growth factor-β receptors (TGFβR), and T cell receptor (TCR). In addition to NFκB, TRAF6 may also direct activation of mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K), and interferon regulatory factor (IRF) pathways. In the context of the immune system, TRAF6-mediated signals have proven critical for the development, homeostasis, and/or activation of B cells, T cells, and myeloid cells, including macrophages, dendritic cells, and osteoclasts, as well as for organogenesis of thymic and secondary lymphoid tissues. In multiple cellular contexts, TRAF6 function is essential not only for proper activation of the immune system, but also for maintaining immune tolerance, and more recent works have begun to identify mechanisms of contextual specificity for TRAF6, involving both regulatory protein interactions, and messenger RNA regulation by microRNAs. PMID:26085208

Application of monoclonal antibodies against trophoblastic cells to study female infertility

Czech Academy of Sciences Publication Activity Database

Sedláková, Alena; Elzeinová, Fatima; Bukovský, A.; Madar, J.; Ulčová-Gallová, Z.; Pěknicová, Jana

2004-01-01

Roč. 51, č. 6 (2004), s. 482-483 ISSN 1046-7408. [European congress of reproductive immunology. Plzeň, 30.06.2004-03.07.2004] R&D Projects: GA MŠk LN00B030 Keywords : trophoblast * monoclonal antibody * ELISA Subject RIV: EC - Immunology Impact factor: 1.808, year: 2004

Development and Characterization of Canine Distemper Virus Monoclonal Antibodies.

Science.gov (United States)

Liu, Yuxiu; Hao, Liying; Li, Xiangdong; Wang, Linxiao; Zhang, Jianpo; Deng, Junhua; Tian, Kegong

2017-06-01

Five canine distemper virus monoclonal antibodies were developed by immunizing BALB/c mice with a traditional vaccine strain Snyder Hill. Among these monoclonal antibodies, four antibodies recognized both field and vaccine strains of canine distemper virus without neutralizing ability. One monoclonal antibody, 1A4, against hemagglutinin protein of canine distemper virus was found to react only with vaccine strain virus but not field isolates, and showed neutralizing activity to vaccine strain virus. These monoclonal antibodies could be very useful tools in the study of the pathogenesis of canine distemper virus and the development of diagnostic reagents.

Production and Purification of Monoclonal Antibody Against Tumor Marker of TPA

Directory of Open Access Journals (Sweden)

Seyyed Amir Abbas Ghodrat

2016-05-01

Full Text Available Considering the invasive nature of cancer cells, one of the most important and best indicator of them is the markers inside them. One of the most important markers that observed in some types of cancer cells in various parts of the body is the Cytokeratin. Tissue plasminogen activator antigen (TPA is a Cytokeratin composed of molecules with various molecular weights. The level of TPA serum as associated with cellular growth level and tumorization of cells. In this research, the hybrid of spleen cells in BALB/c female mouse with myeloma cells was conducted with a ratio of 10:1. The resulting monoclonal antibodies were confirmed by SDS-PAGE and western blot. Protein G chromatography was utilized to purify monoclonal antibodies. The results for determining isotypes showed IgM and IgG classes. The titer of the antibody obtained from various clones was capable of identifying Cytokeratin antigen with a dilution of 1/10000. The resulting antibodies were finally confirmed by western blot and all the 5 resulting monoclonal antibodies were capable of identifying a 48 kDa protein. The results indicate that with the help of TPA marker and the monoclonal antibodies produced against them, this marker can be recognized quickly with great accuracy in suspicious cases of cancer. Thus, appropriate measures will be taken to prevent and fight off its probable side effects. This factor can be further used to build a diagonal kit with high sensitivity.

Nerve growth factor receptor immunostaining suggests an extrinsic origin for hypertrophic nerves in Hirschsprung's disease.

OpenAIRE

Kobayashi, H; O'Briain, D S; Puri, P

1994-01-01

The expression of nerve growth factor receptor in colon from 20 patients with Hirshsprung's disease and 10 controls was studied immunohistochemically. The myenteric and submucous plexuses in the ganglionic bowel and hypertrophic nerve trunks in the aganglionic bowel displayed strong expression of nerve growth factor receptor. The most important finding was the identical localisation of nerve growth factor receptor immunoreactivity on the perineurium of both hypertrophic nerve trunks in Hirshs...

Effects of anti-vascular endothelial growth factor monoclonal antibody (bevacizumab on lens epithelial cells

Directory of Open Access Journals (Sweden)

Jun JH

2016-06-01

Full Text Available Jong Hwa Jun,1 Wern-Joo Sohn,2 Youngkyun Lee,2 Jae-Young Kim21Department of Ophthalmology, School of Medicine, Dongsan Medical Center, Keimyung University, 2Department of Oral Biochemistry, School of Dentistry, IHBR, Kyungpook National University, Daegu, South KoreaAbstract: The molecular and cellular effects of anti-vascular endothelial growth factor monoclonal antibody (bevacizumab on lens epithelial cells (LECs were examined using both an immortalized human lens epithelial cell line and a porcine capsular bag model. After treatment with various concentrations of bevacizumab, cell viability and proliferation patterns were evaluated using the water-soluble tetrazolium salt assay and 5-bromo-2'-deoxyuridine enzyme-linked immunosorbent assay, respectively. The scratch assay and Western blot analysis were employed to validate the cell migration pattern and altered expression levels of signaling molecules related to the epithelial–mesenchymal transition (EMT. Application of bevacizumab induced a range of altered cellular events in a concentration-dependent manner. A 0.1–2 mg/mL concentration demonstrated dose-dependent increase in proliferation and viability of LECs. However, 4 mg/mL decreased cell proliferation and viability. Cell migrations displayed dose-dependent retardation from 0.1 mg/mL bevacizumab treatment. Transforming growth factor-β2 expression was markedly increased in a dose-dependent manner, and α-smooth muscle actin, matrix metalloproteinase-9, and vimentin expression levels showed dose-dependent changes in a B3 cell line. Microscopic observation of porcine capsular bag revealed changes in cellular morphology and a decline in cell density compared to the control after 2 mg/mL treatment. The central aspect of posterior capsule showed delayed confluence, and the factors related to EMT revealed similar expression patterns to those identified in the cell line. Based on these results, bevacizumab modulates the proliferation

Monoclonal antibody Zt/g4 targeting RON receptor tyrosine kinase enhances chemosensitivity of bladder cancer cells to Epirubicin by promoting G1/S arrest and apoptosis.

Science.gov (United States)

Chen, Jun-Feng; Yu, Bi-Xia; Yu, Rui; Ma, Liang; Lv, Xiu-Yi; Cheng, Yue; Ma, Qi

2017-02-01

Epirubicin (EPI) is one of the most used intravesical chemotherapy agents after transurethral resection to non-muscle invasive bladder tumors (NMIBC) to prevent cancer recurrence and progression. However, even after resection of bladder tumors and intravesical chemotherapy, half of them will recur and progress. RON is a membrane tyrosine kinase receptor usually overexpressed in bladder cancer cells and associated with poor pathological features. This study aims to investigate the effects of anti-RON monoclonal antibody Zt/g4 on the chemosensitivity of bladder cells to EPI. After Zt/g4 treatment, cell cytotoxicity was significantly increased and cell invasion was markedly suppressed in EPI-treated bladder cancer cells. Further investigation indicated that combing Zt/g4 with EPI promoted cell G1/S-phase arrest and apoptosis, which are the potential mechanisms that RON signaling inhibition enhances chemosensitivity of EPI. Thus, combing antibody-based RON targeted therapy enhances the therapeutic effects of intravesical chemotherapy, which provides new strategy for further improvement of NMIBC patient outcomes.

Metabotropic glutamate receptor 2 and corticotrophin-releasing factor receptor-1 gene expression is differently regulated by BDNF in rat primary cortical neurons

DEFF Research Database (Denmark)

Jørgensen, Christinna V; Klein, Anders B; El-Sayed, Mona

2013-01-01

Brain-derived neurotrophic factor (BDNF) is important for neuronal survival and plasticity. Incorporation of matured receptor proteins is an integral part of synapse formation. However, whether BDNF increases synthesis and integration of receptors in functional synapses directly is unclear. We...... are particularly interested in the regulation of the 5-hydroxytryptamine receptor 2A (5-HT2A R). This receptor form a functional complex with the metabotropic glutamate receptor 2 (mGluR2) and is recruited to the cell membrane by the corticotrophin-releasing factor receptor 1 (CRF-R1). The effect of BDNF on gene...... expression for all these receptors, as well as a number of immediate-early genes, was pharmacologically characterized in primary neurons from rat frontal cortex. BDNF increased CRF-R1 mRNA levels up to fivefold, whereas mGluR2 mRNA levels were proportionally downregulated. No effect on 5-HT2A R mRNA was seen...

Fc receptors for mouse IgG1 on human monocytes: polymorphism and role in antibody-induced T cell proliferation.

Science.gov (United States)

Tax, W J; Hermes, F F; Willems, R W; Capel, P J; Koene, R A

1984-09-01

In previous studies, it was shown that there is polymorphism in the mitogenic effect of mouse IgG1 monoclonal antibodies against the T3 antigen of human T cells. This polymorphism implies that IgG1 anti-T3 antibodies are not mitogenic for T cells from 30% of healthy individuals. The present results demonstrate that this polymorphism is caused by polymorphism of an Fc receptor for mouse IgG1, present on human monocytes. The Fc receptor for murine IgG1 could be detected by a newly developed rosetting assay on monocytes from all individuals responsive to the mitogenic effect of IgG1 anti-T3 antibodies. This Fc receptor was not detectable on monocytes from those individuals exhibiting no mitogenic responses to IgG1 anti-T3 monoclonal antibodies. Cross-linking of T3 antigens appears to be essential for antibody-induced mitosis of T cells, because mononuclear cells that did not proliferate in response to WT 31 (an IgG1 antibody against T3 antigen) showed a proliferative response to Sepharose beads coated with WT 31. The Fc receptor--if functionally present--may be involved in the cross-linking of T3 antigens through anti-T3 antibodies. Further evidence for the involvement of this Fc receptor in antibody-induced T cell proliferation was provided by inhibition studies. Immune complexes containing IgG1 antibodies were able to inhibit the proliferative response to IgG1 anti-T3 antibodies. This inhibition by immune complexes appears to be mediated through the monocyte Fc receptor for mouse IgG1. These findings are important for the interpretation of previously described inhibitory effects of anti-T cell monoclonal antibodies on T cell proliferation, and show that such inhibitory effects may be monocyte-mediated (via immune complexes) rather than caused by a direct involvement of the respective T cell antigens in T cell mitosis. The Fc receptor for mouse IgG1 plays a role in antibody-induced T cell proliferation. Its polymorphism may have important implications for the

Multiple autophosphorylation sites of the epidermal growth factor receptor are essential for receptor kinase activity and internalization. Contrasting significance of tyrosine 992 in the native and truncated receptors

DEFF Research Database (Denmark)

Sorkin, A; Helin, K; Waters, C M

1992-01-01

The role of epidermal growth factor (EGF) receptor autophosphorylation sites in the regulation of receptor functions has been studied using cells transfected with mutant EGF receptors. Simultaneous point mutation of 4 tyrosines (Y1068, Y1086, Y1148, Y1173) to phenylalanine, as well as removal of ...

Development of an ErbB4 monoclonal antibody that blocks neuregulin-1-induced ErbB4 activation in cancer cells

Energy Technology Data Exchange (ETDEWEB)

Okazaki, Shogo [Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Nakatani, Fumi [Cell Biology Laboratory, Department of Pharmaceutical Sciences, Faculty of Pharmacy, Kinki University, Higashiosaka, Osaka 577-8502 Japan (Japan); Masuko, Kazue; Tsuchihashi, Kenji [Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Ueda, Shiho; Masuko, Takashi [Cell Biology Laboratory, Department of Pharmaceutical Sciences, Faculty of Pharmacy, Kinki University, Higashiosaka, Osaka 577-8502 Japan (Japan); Saya, Hideyuki [Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Nagano, Osamu, E-mail: osmna@sb3.so-net.ne.jp [Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan)

2016-01-29

The use of monoclonal antibodies (mAbs) for cancer therapy is one of the most important strategies for current cancer treatment. The epidermal growth factor receptor (EGFR) family of receptor tyrosine kinases, which regulates cancer cell proliferation, survival, and migration, is a major molecular target for antibody-based therapy. ErbB4/HER4, which contains a ligand-binding extracellular region, is activated by several ligands, including neuregulins (NRGs), heparin-binding EGF-like growth factor, betacellulin and epiregulin. Although there are clinically approved antibodies for ErbB1 and ErbB2, there are no available therapeutic mAbs for ErbB4, and it is not known whether ErbB4 is a useful target for antibody-based cancer therapy. In this study, we developed an anti-ErbB4 mAb (clone P6-1) that suppresses NRG-dependent activation of ErbB4 and examined its effect on breast cancer cell proliferation in the extracellular matrix. - Highlights: • We newly generated four clones of human ErbB4 specific mAb. • ErbB4 mAb clone P6-1 blocks ErbB4 phosphorylation induced by NRG-1. • ErbB4 mAb clone P6-1 suppresses NRG-1-promoted breast cancer cells proliferation on three dimensional culture condition.

Development of an ErbB4 monoclonal antibody that blocks neuregulin-1-induced ErbB4 activation in cancer cells

International Nuclear Information System (INIS)

Okazaki, Shogo; Nakatani, Fumi; Masuko, Kazue; Tsuchihashi, Kenji; Ueda, Shiho; Masuko, Takashi; Saya, Hideyuki; Nagano, Osamu

2016-01-01

The use of monoclonal antibodies (mAbs) for cancer therapy is one of the most important strategies for current cancer treatment. The epidermal growth factor receptor (EGFR) family of receptor tyrosine kinases, which regulates cancer cell proliferation, survival, and migration, is a major molecular target for antibody-based therapy. ErbB4/HER4, which contains a ligand-binding extracellular region, is activated by several ligands, including neuregulins (NRGs), heparin-binding EGF-like growth factor, betacellulin and epiregulin. Although there are clinically approved antibodies for ErbB1 and ErbB2, there are no available therapeutic mAbs for ErbB4, and it is not known whether ErbB4 is a useful target for antibody-based cancer therapy. In this study, we developed an anti-ErbB4 mAb (clone P6-1) that suppresses NRG-dependent activation of ErbB4 and examined its effect on breast cancer cell proliferation in the extracellular matrix. - Highlights: • We newly generated four clones of human ErbB4 specific mAb. • ErbB4 mAb clone P6-1 blocks ErbB4 phosphorylation induced by NRG-1. • ErbB4 mAb clone P6-1 suppresses NRG-1-promoted breast cancer cells proliferation on three dimensional culture condition.

Monoclonal antibody PAL-E specific for endothelium

NARCIS (Netherlands)

Schlingemann, R. O.; Dingjan, G. M.; Emeis, J. J.; Blok, J.; Warnaar, S. O.; Ruiter, D. J.

1985-01-01

A monoclonal antibody, PAL-E, is described that is specific for endothelial cells. The monoclonal antibody, an IgG2a, markedly stains endothelium of capillaries, medium-sized and small veins, and venules in frozen sections of human and some animal tissues tested. It reacts not at all or only weakly

Monoclonal for cancer detection and therapy

International Nuclear Information System (INIS)

Baldwin, R.W.; Byers, V.S.

1985-01-01

This book contains 18 chapters. Some of the chapter titles are: Monoclonal Antibodies to Breast Cancer and Their Application; Clinical Applications of Radioimmunolocalisation; Localisation of Cancer of the Ovary and Metastases Using 123 I-labelled Monoclonal Antibody HMFG-2 Compared to Surgical Findings; Interest of Globotriaosylceramide Membrane Antigen as Target for Immunotoxins; and Analysis, Results and Future Prospective of the Therapeutic Use of Radiolabeled Antibody in Cancer Therapy

Altered [125I]epidermal growth factor binding and receptor distribution in psoriasis

International Nuclear Information System (INIS)

Nanney, L.B.; Stoscheck, C.M.; Magid, M.; King, L.E. Jr.

1986-01-01

Stimulation of growth and differentiation of human epidermis by epidermal growth factor (EGF) is mediated by its binding to specific receptors. Whether EGF receptors primarily mediate cell division or differentiation in hyperproliferative disease such as psoriasis vulgaris is unclear. To study the pathogenesis of psoriasis, 4-mm2 punch biopsy specimens of normal, uninvolved, and involved psoriatic skin were assayed for EGF receptors by autoradiographic, immunohistochemical, and biochemical methods. Using autoradiographic and immunohistochemical methods, basal keratinocytes were found to contain the greatest number of EGF binding sites and immunoreactive receptors as compared to the upper layers of the epidermis in both normal epidermis and psoriatic skin. No EGF receptor differences between normal and psoriatic epidermis were observed in this layer. In the upper layers of the epidermis, a 2-fold increase in EGF binding capacity was observed in psoriatic skin as compared with normal thin or thick skin. Biochemical methods indicated that [ 125 I]EGF binding was increased in psoriatic epidermis as compared with similar thickness normal epidermis when measured on a protein basis. Epidermal growth factor was shown to increase phosphorylation of the EGF receptor in skin. EGF receptors retained in the nonmitotic stratum spinosum and parakeratotic stratum corneum may reflect the incomplete, abnormal differentiation that occurs in active psoriatic lesions. Alternatively, retained EGF receptors may play a direct role in inhibiting cellular differentiation in the suprabasal layers

Epidermal growth factor receptor (EGFR) and EGFR mutations, function and possible role in clinical trials

DEFF Research Database (Denmark)

Voldborg, B R; Damstrup, L; Spang-Thomsen, M

1997-01-01

The epidermal growth factor receptor (EGFR) is a growth factor receptor that induces cell differentiation and proliferation upon activation through the binding of one of its ligands. The receptor is located at the cell surface, where the binding of a ligand activates a tyrosine kinase in the intr...... aspects of therapeutic targeting of EGFR....

Internalization mechanisms of the epidermal growth factor receptor after activation with different ligands.

Directory of Open Access Journals (Sweden)

Lasse Henriksen

Full Text Available The epidermal growth factor receptor (EGFR regulates normal growth and differentiation, but dysregulation of the receptor or one of the EGFR ligands is involved in the pathogenesis of many cancers. There are eight ligands for EGFR, however most of the research into trafficking of the receptor after ligand activation focuses on the effect of epidermal growth factor (EGF and transforming growth factor-α (TGF-α. For a long time it was believed that clathrin-mediated endocytosis was the major pathway for internalization of the receptor, but recent work suggests that different pathways exist. Here we show that clathrin ablation completely inhibits internalization of EGF- and TGF-α-stimulated receptor, however the inhibition of receptor internalization in cells treated with heparin-binding EGF-like growth factor (HB-EGF or betacellulin (BTC was only partial. In contrast, clathrin knockdown fully inhibits EGFR degradation after all ligands tested. Furthermore, inhibition of dynamin function blocked EGFR internalization after stimulation with all ligands. Knocking out a number of clathrin-independent dynamin-dependent pathways of internalization had no effect on the ligand-induced endocytosis of the EGFR. We suggest that EGF and TGF-α lead to EGFR endocytosis mainly via the clathrin-mediated pathway. Furthermore, we suggest that HB-EGF and BTC also lead to EGFR endocytosis via a clathrin-mediated pathway, but can additionally use an unidentified internalization pathway or better recruit the small amount of clathrin remaining after clathrin knockdown.

Internalization Mechanisms of the Epidermal Growth Factor Receptor after Activation with Different Ligands

Science.gov (United States)

Henriksen, Lasse; Grandal, Michael Vibo; Knudsen, Stine Louise Jeppe; van Deurs, Bo; Grøvdal, Lene Melsæther

2013-01-01

The epidermal growth factor receptor (EGFR) regulates normal growth and differentiation, but dysregulation of the receptor or one of the EGFR ligands is involved in the pathogenesis of many cancers. There are eight ligands for EGFR, however most of the research into trafficking of the receptor after ligand activation focuses on the effect of epidermal growth factor (EGF) and transforming growth factor-α (TGF-α). For a long time it was believed that clathrin-mediated endocytosis was the major pathway for internalization of the receptor, but recent work suggests that different pathways exist. Here we show that clathrin ablation completely inhibits internalization of EGF- and TGF-α-stimulated receptor, however the inhibition of receptor internalization in cells treated with heparin-binding EGF-like growth factor (HB-EGF) or betacellulin (BTC) was only partial. In contrast, clathrin knockdown fully inhibits EGFR degradation after all ligands tested. Furthermore, inhibition of dynamin function blocked EGFR internalization after stimulation with all ligands. Knocking out a number of clathrin-independent dynamin-dependent pathways of internalization had no effect on the ligand-induced endocytosis of the EGFR. We suggest that EGF and TGF-α lead to EGFR endocytosis mainly via the clathrin-mediated pathway. Furthermore, we suggest that HB-EGF and BTC also lead to EGFR endocytosis via a clathrin-mediated pathway, but can additionally use an unidentified internalization pathway or better recruit the small amount of clathrin remaining after clathrin knockdown. PMID:23472148

Insulin and insulin-like growth factor receptors and responses

International Nuclear Information System (INIS)

Roth, R.A.; Steele-Perkins, G.; Hari, J.; Stover, C.; Pierce, S.; Turner, J.; Edman, J.C.; Rutter, W.J.

1988-01-01

Insulin is a member of a family of structurally related hormones with diverse physiological functions. In humans, the best-characterized members of this family include insulin, insulin-like growth factor (IGF)-I, and IGF-II. Each of these three polypeptide hormones has its own distinct receptor. The structures of each of these receptors have now been deduced from analyses of isolated cDNA clones. To study further the responses mediated through these three different receptors, the authors have been studying cells expressing the proteins encoded by these three cDNAs. The isolated cDNAs have been transfected into Chinese hamster ovary (CHO) cells, and the resulting transfected cell lines have been characterized as to the ligand-binding activities and signal-transducing activities of the expressed proteins

Transferrin receptors on human reticulocytes: variation in site number in hematologic disorders

International Nuclear Information System (INIS)

Shumak, K.H.; Rachkewich, R.A.

1984-01-01

Assays of binding of 125iodine-labeled ( 125 I) human transferrin were used to study transferrin receptor sites on reticulocytes from 15 normal subjects and from 66 patients with various hematologic disorders. In normal subjects, few or no transferrin receptors were detected whereas the average number of receptors per reticulocyte varied greatly from patient to patient, ranging from 0 to 67,700 in samples, from 35 patients, on which Scatchard analysis of binding of [ 125 I]-transferrin was done. Marked heterogeneity in the number of reticulocyte transferrin receptors in different hematologic disorders was also found in assays with [ 125 I]-OKT9 (monoclonal antibody to the human transferrin receptor). The number of receptors was not correlated with either the reticulocyte count or the hemoglobin

Monoclonal antibodies to drosophila cytochrome P-450's

International Nuclear Information System (INIS)

Sundseth, S.S.; Kennel, S.J.; Waters, L.C.

1987-01-01

Hybridomas producing monoclonal antibodies were prepared by the fusion of SP2/0 myeloma cells and spleen cells from a female BALB/c mouse immunized by cytochrome P-450-A and P-450-B purified from Drosophila Hikone-R (BG) microsomes. P-450-A and P-450-B are electrophoretically distinct subsets of Drosophila P-450. P-450-A is ubiquitous among strains tested, while P-450-B is present in only a few strains displaying unique enzyme activities and increased insecticide resistance. The Oregon-R strain contains only cytochromes P-450-A and is susceptible to insecticides. The authors Hikone-R (BG) strain expresses both cytochromes P-450-A and P-450-B and is insecticide resistant. Antibody producing hybridomas were detected in a solid-phase radioimmunoassay (RIA) by binding to Hikone-R (BG) or Oregon-R microsomes. Four independent hybridomas were identified as producing monoclonal antibodies that recognized proteins in the P-450 complex by immunoblot experiments. Three monoclonal antibodies recognized P-450-A proteins, while one monoclonal antibody bound predominantly P-450-B. This monoclonal antibody also recognized southern armyworm (Spodoptera eridania, Cramer) microsomal proteins

A monoclonal antibody to an early pregnancy factor-induced suppressor factor (EPF-S1) disrupts implantation in mice.

Science.gov (United States)

Athanasas-Platsis, S; Hoskin, M J; Rolfe, B E; Cavanagh, A C; Morton, H

1995-03-01

The importance of EPF during pregnancy has been established previously but the importance of the EPF-induced suppressor factor EPF-S1 in pregnancy has to date been unaddressed. Investigations were therefore conducted in order to study this. Monoclonal antibodies to EPF-S1 were produced, and one antibody, designated R2T gamma, was characterized. Mated mice were passively immunized with R2T gamma and the effect on implantation determined. Characterization of anti-EPF-S1 R2T gamma revealed that it cross-reacted with EPF-S1 of different MHC restriction but not with EPF or EPF-S2. When injected into mated mice on days 1 to 4, R2T gamma had no effect on pregnancy but when injections continued to day 5, pregnancy was affected; the number of embryos implanted on day 7 were significantly less than the number of corpora lutea counted, signifying embryonic loss. These studies show that anti-EPF-S1 R2T gamma disrupts implantation in mice when injected on days 1 to 5 of pregnancy but not when injected on days 1 to 4, demonstrating that EPF-S1 exerts its effects around the time of implantation.

Epidermal growth factor receptor: an independent predictor of survival in astrocytic tumors given definitive irradiation

International Nuclear Information System (INIS)

An Zhu; Shaeffer, James; Leslie, Susan; Kolm, Paul; El-Mahdi, Anas M.

1996-01-01

Purpose: To determine whether the expression of epidermal growth factor receptor (EGFR) protein was predictive of patient survival independently of other prognostic factors in astrocytic tumors. Methods and Materials: Epidermal growth factor receptor protein expression was investigated immunohistochemically in formalin-fixed, paraffin-embedded surgical specimens of 55 glioblastoma multiforme, 14 anaplastic astrocytoma, and 2 astrocytomas given definitive irradiation. We evaluated the relationship of EGFR protein expression and tumor grade, histologic features, age at diagnosis, sex, patient survival, and recurrence-free survival. Results: The percentage of tumor cells which were EGFR positive related to reduced survival by Cox regression analysis in both univariate (p = 0.0424) and multivariate analysis (p = 0.0016). Epidermal growth factor receptor positivity was the only 1 of 11 clinical and histological variables associated with decreased recurrence-free survival by either univariate (p = 0.0353) or multivariate (p = 0.0182) analysis. Epidermal growth factor receptor protein expression was not related to patient age, sex, or histologic features. Conclusion: Epidermal growth factor receptor positivity was a significant and independent prognostic indicator for overall survival and recurrence-free survival for irradiated patients with astrocytic gliomas

Early drug development of inhibitors of the insulin-like growth factor-I receptor pathway: lessons from the first clinical trials.

Science.gov (United States)

Rodon, Jordi; DeSantos, Victoria; Ferry, Robert Jean; Kurzrock, Razelle

2008-09-01

The insulin-like growth factor-I receptor (IGF-IR) was first cloned in 1986. Since then, intense work has defined classic phosphorelays activated via the IGF-IR, which regulate cell proliferation, apoptosis, motility, and fate. The understanding of the roles of hormones in cancer and the growth hormone-IGF-IGF-binding protein axis specifically has yield to a second wave of development: the design of specific inhibitors that interrupt the signaling associated with this axis. The ability to manipulate these pathways holds not only significant therapeutic implications but also increase the chance of deeper insight about the role of the axis in carcinogenesis and metastasis. Nowadays, >25 molecules with the same goal are at different stages of development. Here, we review the clinical and preclinical experience with the two most-investigated strategies, tyrosine kinase inhibitors and monoclonal antibodies, and the advantages and disadvantages of each strategy, as well as other alternatives and possible drug combinations. We also review the biomarkers explored in the first clinical trials, the strategies that have been explored thus far, and the clinical trials that are going to explore their role in cancer treatment.

Activated factor X signaling via protease-activated receptor 2 suppresses pro-inflammatory cytokine production from LPS-stimulated myeloid cells.

LENUS (Irish Health Repository)

Gleeson, Eimear M

2013-07-19

Vitamin K-dependent proteases generated in response to vascular injury and infection enable fibrin clot formation, but also trigger distinct immuno-regulatory signaling pathways on myeloid cells. Factor Xa, a protease crucial for blood coagulation, also induces protease-activated receptor-dependent cell signaling. Factor Xa can bind both monocytes and macrophages, but whether factor Xa-dependent signaling stimulates or suppresses myeloid cell cytokine production in response to Toll-like receptor activation is not known. In this study, exposure to factor Xa significantly impaired pro-inflammatory cytokine production from lipopolysaccharide-treated peripheral blood mononuclear cells, THP-1 monocytic cells and murine macrophages. Furthermore, factor Xa inhibited nuclear factor-kappa B activation in THP-1 reporter cells, requiring phosphatidylinositide 3-kinase activity for its anti-inflammatory effect. Active-site blockade, γ-carboxyglutamic acid domain truncation and a peptide mimic of the factor Xa inter-epidermal growth factor-like region prevented factor Xa inhibition of lipopolysaccharide-induced tumour necrosis factor-α release. In addition, factor Xa anti-inflammatory activity was markedly attenuated by the presence of an antagonist of protease-activated receptor 2, but not protease-activated receptor 1. The key role of protease-activated receptor 2 in eliciting factor Xa-dependent anti-inflammatory signaling on macrophages was further underscored by the inability of factor Xa to mediate inhibition of tumour necrosis factor-α and interleukin-6 release from murine bone marrow-derived protease-activated receptor 2-deficient macrophages. We also show for the first time that, in addition to protease-activated receptor 2, factor Xa requires a receptor-associated protein-sensitive low-density lipoprotein receptor to inhibit lipopolysaccharide-induced cytokine production. Collectively, this study supports a novel function for factor Xa as an endogenous, receptor

Receptores do factor estimulante de colónias de macrófagos do robalo

OpenAIRE

Oliveira, Márcio Adriano Guiomar de

2010-01-01

O receptor do factor estimulante de colónias de macrófagos, também conhecido como receptor do factor estimulante de colónias-1 (CSF1R), é um receptor de um factor de crescimento hematopoiético que é especificamente expresso em células do sistema fagocítico-mononuclear e desempenha um papel essencial no desenvolvimento e regulação destas células. O CSF1R já foi descrito em vários mamíferos e a sua biologia tem sido exaustivamente caracterizada nestes vertebrados mas o conheci...

Human Neutralizing Monoclonal Antibody Inhibition of Middle East Respiratory Syndrome Coronavirus Replication in the Common Marmoset.

Science.gov (United States)

Chen, Zhe; Bao, Linlin; Chen, Cong; Zou, Tingting; Xue, Ying; Li, Fengdi; Lv, Qi; Gu, Songzhi; Gao, Xiaopan; Cui, Sheng; Wang, Jianmin; Qin, Chuan; Jin, Qi

2017-06-15

Middle East respiratory syndrome coronavirus (MERS-CoV) infection in humans is highly lethal, with a fatality rate of 35%. New prophylactic and therapeutic strategies to combat human infections are urgently needed. We isolated a fully human neutralizing antibody, MCA1, from a human survivor. The antibody recognizes the receptor-binding domain of MERS-CoV S glycoprotein and interferes with the interaction between viral S and the human cellular receptor human dipeptidyl peptidase 4 (DPP4). To our knowledge, this study is the first to report a human neutralizing monoclonal antibody that completely inhibits MERS-CoV replication in common marmosets. Monotherapy with MCA1 represents a potential alternative treatment for human infections with MERS-CoV worthy of evaluation in clinical settings. © Crown copyright 2017.

Management of Patients With Hepatitis C Virus, Monoclonal Gammopathy of Undetermined Significance, and Multiple Myeloma

Directory of Open Access Journals (Sweden)

Alisse Hannaford BS

2017-04-01

Full Text Available Background and Aim: The vast majority of the 2.7 million individuals in the United States who are currently infected with hepatitis C virus (HCV were born between 1945 and 1965. The median age of these patients in this particular generation at the time of this writing was 55 years. In the general population, older age is a risk factor for multiple myeloma (MM and other monogammopathies. As the baby boomer population ages, HCV providers are increasingly likely to encounter HCV-infected patients with a monoclonal gammopathy. Guidelines for managing these patients are needed. Methods: We conducted a detailed case series investigation of 4 HCV-positive patients with MM or a monoclonal gammopathy disorder. Patients were followed at the Mount Sinai Faculty Practice liver clinic. We also performed a detailed review of the literature exploring if there is any known association between HCV, MM, and monoclonal gammopathy. Results and Conclusions: There is no convincing evidence of a causal association between HCV and MM. HCV is linked to type II and type III cryoglobulinemia, specific kinds of monoclonal gammopathies of determinable significance. Whether a link exists between HCV and MM or monoclonal gammopathy of undetermined significance is unclear. Our case series provides the first evidence that modern HCV treatments with direct-acting antivirals can be safely and effectively co-administered with MM chemotherapy.

ADCC responses and blocking of EGFR-mediated signaling and cell growth by combining the anti-EGFR antibodies imgatuzumab and cetuximab in NSCLC cells

NARCIS (Netherlands)

Kol, Arjan; Terwisscha van Scheltinga, Anton; Pool, Martin; Gerdes, Christian; de Vries, Elisabeth; de Jong, Steven

2017-01-01

Imgatuzumab is a novel glycoengineered anti-epidermal growth factor receptor (EGFR) monoclonal antibody optimized to induce both antibody-dependent cellular cytotoxicity (ADCC) and EGFR signal transduction inhibition. We investigated antiEGFR monoclonal antibodies imgatuzumab and cetuximab-induced

Analysis of receptor signaling pathways by mass spectrometry: identification of vav-2 as a substrate of the epidermal and platelet-derived growth factor receptors

DEFF Research Database (Denmark)

Pandey, A; Podtelejnikov, A V; Blagoev, B

2000-01-01

Oligomerization of receptor protein tyrosine kinases such as the epidermal growth factor receptor (EGFR) by their cognate ligands leads to activation of the receptor. Transphosphorylation of the receptor subunits is followed by the recruitment of signaling molecules containing src homology 2 (SH2...

Identification of fibroblast growth factor receptor 3 (FGFR3 as a protein receptor for botulinum neurotoxin serotype A (BoNT/A.

Directory of Open Access Journals (Sweden)

Birgitte P S Jacky

Full Text Available Botulinum neurotoxin serotype A (BoNT/A causes transient muscle paralysis by entering motor nerve terminals (MNTs where it cleaves the SNARE protein Synaptosomal-associated protein 25 (SNAP25206 to yield SNAP25197. Cleavage of SNAP25 results in blockage of synaptic vesicle fusion and inhibition of the release of acetylcholine. The specific uptake of BoNT/A into pre-synaptic nerve terminals is a tightly controlled multistep process, involving a combination of high and low affinity receptors. Interestingly, the C-terminal binding domain region of BoNT/A, HC/A, is homologous to fibroblast growth factors (FGFs, making it a possible ligand for Fibroblast Growth Factor Receptors (FGFRs. Here we present data supporting the identification of Fibroblast Growth Factor Receptor 3 (FGFR3 as a high affinity receptor for BoNT/A in neuronal cells. HC/A binds with high affinity to the two extra-cellular loops of FGFR3 and acts similar to an agonist ligand for FGFR3, resulting in phosphorylation of the receptor. Native ligands for FGFR3; FGF1, FGF2, and FGF9 compete for binding to FGFR3 and block BoNT/A cellular uptake. These findings show that FGFR3 plays a pivotal role in the specific uptake of BoNT/A across the cell membrane being part of a larger receptor complex involving ganglioside- and protein-protein interactions.

Monoclonal gammopathy in rheumatic diseases.

Science.gov (United States)

Yang, Yue; Chen, Long; Jia, Yuan; Liu, Yang; Wen, Lei; Liang, Yaoxian; An, Yuan; Chen, Shi; Su, Yin; Li, Zhanguo

2018-07-01

To analyze the clinical spectrum, laboratory characteristics, and outcomes of monoclonal gammopathy (MG) in patients with rheumatic diseases. Screening for the presence of MG was performed in 872 inpatients with rheumatic diseases from January 2010 to July 2017. A total of 41 patients were enrolled. Their clinical and biological features in addition to outcomes were described. For each patient with primary Sjögren syndrome (pSS), 2 age- and sex-matched pSS patients without MG were selected as controls. Risk factors for the presence of MG and malignant hematological neoplasias were assessed. MG was observed in patients with SS, rheumatoid arthritis, systemic lupus erythematosus, ankylosing spondylitis, primary biliary cirrhosis, polymyositis, hypomyopathic dermatomyositis, psoriatic arthritis, ANCA-associated vasculitis, polyarteritis nodosa, and polymyalgia rheumatic, with SS the most frequent type. Serum M protein was detected in 37 patients. The monoclonal bands identified in serum were 16 IgG (5 κ, 11 λ), 11 IgA (6 κ, 5 λ), 6 IgM (5 κ, 1 λ), and 4 free λ chains. M components were observed in urine in the other 4 patients. High ESR, albumin/globulin inversion, rheumatoid factor positivity, hypergammaglobulinemia, and hypocomplementemia were common features, presented in more than half of the 41 patients. Patients with pSS, when complicated with MG, showed a higher rate of abnormal urine NAG (71.4 vs 15.8%, P = 0.025), higher levels of ESR [55.0 (53.5) mm/h vs 21.0 (31.8) mm/h, P = 0.001], ESSDAI [26.0 (25.0) vs 12.0 (9.0), P = 0.006], and ClinESSDAI scores [24.0 (25.0) vs 10.5 (10.0), P = 0.011]. Multivariate analysis revealed that the disease activity, assessed by either ESSDAI [adjusted OR 1.127 (95%CI 1.015-1.251), P = 0.025] or ClinESSDAI [adjusted OR 1.121 (95%CI 1.011-1.242), P = 0.030], was the only independent risk factor for the presence of MG. During the follow-up, 2 patients had transient serum M protein, 2 had isotype

Epitope Mapping of Monoclonal Antibody PMab-48 Against Dog Podoplanin.

Science.gov (United States)

Yamada, Shinji; Kaneko, Mika K; Itai, Shunsuke; Chang, Yao-Wen; Nakamura, Takuro; Yanaka, Miyuki; Ogasawara, Satoshi; Murata, Takeshi; Uchida, Hiroaki; Tahara, Hideaki; Harada, Hiroyuki; Kato, Yukinari

2018-04-02

Podoplanin (PDPN), a type I transmembrane sialoglycoprotein, is expressed on normal renal podocytes, pulmonary type I alveolar cells, and lymphatic endothelial cells. Increased expression of PDPN in cancers is associated with poor prognosis and hematogenous metastasis through interactions with C-type lectin-like receptor 2 (CLEC-2) on platelets. We previously reported a novel PMab-48 antibody, which is an anti-dog PDPN (dPDPN) monoclonal antibody (mAb) recognizing PDPN expressed in lymphatic endothelial cells. However, the binding epitope of PMab-48 is yet to be clarified. In this study, an enzyme-linked immunosorbent assay and flow cytometry were used to investigate epitopes of PMab-48. The results revealed that the critical epitope of PMab-48 comprises Asp29, Asp30, Ile31, Ile32, and Pro33 of dPDPN.

Phenobarbital indirectly activates the constitutive active androstane receptor (CAR) by inhibition of epidermal growth factor receptor signaling.

Science.gov (United States)

Mutoh, Shingo; Sobhany, Mack; Moore, Rick; Perera, Lalith; Pedersen, Lee; Sueyoshi, Tatsuya; Negishi, Masahiko

2013-05-07

Phenobarbital is a central nervous system depressant that also indirectly activates nuclear receptor constitutive active androstane receptor (CAR), which promotes drug and energy metabolism, as well as cell growth (and death), in the liver. We found that phenobarbital activated CAR by inhibiting epidermal growth factor receptor (EGFR) signaling. Phenobarbital bound to EGFR and potently inhibited the binding of EGF, which prevented the activation of EGFR. This abrogation of EGFR signaling induced the dephosphorylation of receptor for activated C kinase 1 (RACK1) at Tyr(52), which then promoted the dephosphorylation of CAR at Thr(38) by the catalytic core subunit of protein phosphatase 2A. The findings demonstrated that the phenobarbital-induced mechanism of CAR dephosphorylation and activation is mediated through its direct interaction with and inhibition of EGFR.

Monoclonal antibodies in oncology. Review article

Energy Technology Data Exchange (ETDEWEB)

Chan, S Y.T.; Sikora, K

1986-05-01

Monoclonal antibodies (MCAs) can be used to differentiate between normal and neoplastic cells and thus exploited for diagnostic and, ultimately, therapeutic gain. The evidence for the existence of human tumour antigens is reviewed. Several areas of diagnosis are already benefiting from the application of the monoclonal technology. Immunohistology can help the pathologist with difficult diagnostic problems. New classifications of lymphoma and leukaemia can be based on specific surface molecules. Similarly, the detection of shed tumour antigens is already established as part of the routine assessment of many patients with common solid tumours. Isotopically labeled monoclonal antibodies have been used to localise primary and metastatic tumours. The use of antibodies in this way is not only a promising diagnostic tool but also the first step in studying the possibility of arming antibodies to provide therapeutic agents. Such trials are currently in progress. 69 refs.; 7 figs.; 3 tabs.

New monoclonal antibodies to rat testicular antigen, TEC-21

Czech Academy of Sciences Publication Activity Database

Hálová, Ivana; Dráberová, Lubica; Dráber, Petr

2001-01-01

Roč. 47, č. 5 (2001), s. 180-182 ISSN 0015-5500 R&D Projects: GA ČR GV312/96/K205; GA ČR GA204/00/0204; GA ČR GA310/00/0205; GA AV ČR IAA5052005; GA AV ČR IAA7052006; GA MŠk LN00A026 Keywords : Monoclonal antibody * lipid raft * testicular cells Subject RIV: EC - Immunology Impact factor: 0.519, year: 2001

Development of therapeutic antibodies to G protein-coupled receptors and ion channels: Opportunities, challenges and their therapeutic potential in respiratory diseases.

Science.gov (United States)

Douthwaite, Julie A; Finch, Donna K; Mustelin, Tomas; Wilkinson, Trevor C I

2017-01-01

The development of recombinant antibody therapeutics continues to be a significant area of growth in the pharmaceutical industry with almost 50 approved monoclonal antibodies on the market in the US and Europe. Therapeutic drug targets such as soluble cytokines, growth factors and single transmembrane spanning receptors have been successfully targeted by recombinant monoclonal antibodies and the development of new product candidates continues. Despite this growth, however, certain classes of important disease targets have remained intractable to therapeutic antibodies due to the complexity of the target molecules. These complex target molecules include G protein-coupled receptors and ion channels which represent a large target class for therapeutic intervention with monoclonal antibodies. Although these targets have typically been addressed by small molecule approaches, the exquisite specificity of antibodies provides a significant opportunity to provide selective modulation of these important regulators of cell function. Given this opportunity, a significant effort has been applied to address the challenges of targeting these complex molecules and a number of targets are linked to the pathophysiology of respiratory diseases. In this review, we provide a summary of the importance of GPCRs and ion channels involved in respiratory disease and discuss advantages offered by antibodies as therapeutics at these targets. We highlight some recent GPCRs and ion channels linked to respiratory disease mechanisms and describe in detail recent progress made in the strategies for discovery of functional antibodies against challenging membrane protein targets such as GPCRs and ion channels. Copyright © 2016 Elsevier Inc. All rights reserved.

ErbB2 resembles an autoinhibited invertebrate epidermal growth factor receptor

Energy Technology Data Exchange (ETDEWEB)

Alvarado, Diego; Klein, Daryl E.; Lemmon, Mark A.; (UPENN-MED)

2009-09-25

The orphan receptor tyrosine kinase ErbB2 (also known as HER2 or Neu) transforms cells when overexpressed, and it is an important therapeutic target in human cancer. Structural studies have suggested that the oncogenic (and ligand-independent) signalling properties of ErbB2 result from the absence of a key intramolecular 'tether' in the extracellular region that autoinhibits other human ErbB receptors, including the epidermal growth factor (EGF) receptor. Although ErbB2 is unique among the four human ErbB receptors, here we show that it is the closest structural relative of the single EGF receptor family member in Drosophila melanogaster (dEGFR). Genetic and biochemical data show that dEGFR is tightly regulated by growth factor ligands, yet a crystal structure shows that it, too, lacks the intramolecular tether seen in human EGFR, ErbB3 and ErbB4. Instead, a distinct set of autoinhibitory interdomain interactions hold unliganded dEGFR in an inactive state. All of these interactions are maintained (and even extended) in ErbB2, arguing against the suggestion that ErbB2 lacks autoinhibition. We therefore suggest that normal and pathogenic ErbB2 signalling may be regulated by ligands in the same way as dEGFR. Our findings have important implications for ErbB2 regulation in human cancer, and for developing therapeutic approaches that target novel aspects of this orphan receptor.

Crossreactivity of boar sperm monoclonal antibodies with human ...

African Journals Online (AJOL)

Monoclonal antibodies against the head (H mabs) and tail (Tmabs) of boar spermatozoa were produced. Spermatozoa from boar, stallion, bull, human, ram, goat and rabbit were independently incubated with the monoclonal antibodies and later stained by immunofluorescence method. There were positive reactions of the ...

The development of epidermal growth factor receptor molecular imaging in cancer

International Nuclear Information System (INIS)

Zhou Xiaoliang; Wang Hao; Shi Peiji; Liu Jianfeng; Meng Aimin

2013-01-01

In vivo epidermal growth factor receptor (EGFR) targeted therapy has great potential for cancer diagnosis and the evaluation of curative effects. Enhancement of EGFR-targeted therapy needs a reliable quantitative molecular imaging method which could enable monitoring of receptor drug binding and receptor occupancy in vivo, and identification of the mutation in EGFR. PET or SPECT is the most advanced molecular imaging technology of non-invasively selecting responders, predicting therapeutic outcome and monitoring EGFR-targeted treatment. This review analyzed the present situation and research progress of molecular imaging agents. (authors)

Two signaling molecules share a phosphotyrosine-containing binding site in the platelet-derived growth factor receptor.

Science.gov (United States)

Nishimura, R; Li, W; Kashishian, A; Mondino, A; Zhou, M; Cooper, J; Schlessinger, J

1993-11-01

Autophosphorylation sites of growth factor receptors with tyrosine kinase activity function as specific binding sites for Src homology 2 (SH2) domains of signaling molecules. This interaction appears to be a crucial step in a mechanism by which receptor tyrosine kinases relay signals to downstream signaling pathways. Nck is a widely expressed protein consisting exclusively of SH2 and SH3 domains, the overexpression of which causes cell transformation. It has been shown that various growth factors stimulate the phosphorylation of Nck and its association with autophosphorylated growth factor receptors. A panel of platelet-derived growth factor (PDGF) receptor mutations at tyrosine residues has been used to identify the Nck binding site. Here we show that mutation at Tyr-751 of the PDGF beta-receptor eliminates Nck binding both in vitro and in living cells. Moreover, the Y751F PDGF receptor mutant failed to mediate PDGF-stimulated phosphorylation of Nck in intact cells. A phosphorylated Tyr-751 is also required for binding of phosphatidylinositol-3 kinase to the PDGF receptor. Hence, the SH2 domains of p85 and Nck share a binding site in the PDGF receptor. Competition experiments with different phosphopeptides derived from the PDGF receptor suggest that binding of Nck and p85 is influenced by different residues around Tyr-751. Thus, a single tyrosine autophosphorylation site is able to link the PDGF receptor to two distinct SH2 domain-containing signaling molecules.

Lessons from the Crystal Structure of the S. aureus Surface Protein Clumping Factor A in Complex With Tefibazumab, an Inhibiting Monoclonal Antibody

Directory of Open Access Journals (Sweden)

Vannakambadi K. Ganesh

2016-11-01

Full Text Available The Staphylococcus aureus fibrinogen binding MSCRAMM (Microbial Surface Components Recognizing Adhesive Matrix Molecules, ClfA (clumping factor A is an important virulence factor in staphylococcal infections and a component of several vaccines currently under clinical evaluation. The mouse monoclonal antibody aurexis (also called 12-9, and the humanized version tefibazumab are therapeutic monoclonal antibodies targeting ClfA that in combination with conventional antibiotics were effective in animal models but showed less impressive efficacy in a limited Phase II clinical trial. We here report the crystal structure and a biochemical characterization of the ClfA/tefibazumab (Fab complex. The epitope for tefibazumab is located to the “top” of the N3 subdomain of ClfA and partially overlaps with a previously unidentified second binding site for fibrinogen. A high-affinity binding of ClfA to fibrinogen involves both an interaction at the N3 site and the previously identified docking of the C-terminal segment of the fibrinogen γ-chain in the N2N3 trench. Although tefibazumab binds ClfA with high affinity we observe a modest IC50 value for the inhibition of fibrinogen binding to the MSCRAMM. This observation, paired with a common natural occurring variant of ClfA that is not effectively recognized by the mAb, may partly explain the modest effect tefibazumab showed in the initial clinic trail. This information will provide guidance for the design of the next generation of therapeutic anti-staphylococcal mAbs targeting ClfA.

SH2 domains of the p85 alpha subunit of phosphatidylinositol 3-kinase regulate binding to growth factor receptors.

Science.gov (United States)

McGlade, C J; Ellis, C; Reedijk, M; Anderson, D; Mbamalu, G; Reith, A D; Panayotou, G; End, P; Bernstein, A; Kazlauskas, A

1992-01-01

The binding of cytoplasmic signaling proteins such as phospholipase C-gamma 1 and Ras GTPase-activating protein to autophosphorylated growth factor receptors is directed by their noncatalytic Src homology region 2 (SH2) domains. The p85 alpha regulatory subunit of phosphatidylinositol (PI) 3-kinase, which associates with several receptor protein-tyrosine kinases, also contains two SH2 domains. Both p85 alpha SH2 domains, when expressed individually as fusion proteins in bacteria, bound stably to the activated beta receptor for platelet-derived growth factor (PDGF). Complex formation required PDGF stimulation and was dependent on receptor tyrosine kinase activity. The bacterial p85 alpha SH2 domains recognized activated beta PDGF receptor which had been immobilized on a filter, indicating that SH2 domains contact autophosphorylated receptors directly. Several receptor tyrosine kinases within the PDGF receptor subfamily, including the colony-stimulating factor 1 receptor and the Steel factor receptor (Kit), also associate with PI 3-kinase in vivo. Bacterially expressed SH2 domains derived from the p85 alpha subunit of PI 3-kinase bound in vitro to the activated colony-stimulating factor 1 receptor and to Kit. We infer that the SH2 domains of p85 alpha bind to high-affinity sites on these receptors, whose creation is dependent on receptor autophosphorylation. The SH2 domains of p85 are therefore primarily responsible for the binding of PI 3-kinase to activated growth factor receptors. Images PMID:1372092

Decreased expression of serum and microvascular vascular endothelial growth factor receptor-2 in meningococcal sepsis*.

NARCIS (Netherlands)

Flier, M. van der; Baerveldt, E.M.; Miedema, A.; Hartwig, N.G.; Hazelzet, J.A.; Emonts, M.; Groot, R. de; Prens, E.P.; Vught, A.J. van; Jansen, N.J.

2013-01-01

OBJECTIVES: To determine the skin microvessel expression of vascular endothelial growth factor receptor 2 and serum-soluble vascular endothelial growth factor receptor 2 levels in children with meningococcal sepsis. DESIGN: Observational study. SETTING: Two tertiary academic children hospital PICUs.

Production of two hemopoietic growth factors is differentially regulated in single T lymphocytes activated with an anti-T cell receptor antibody

DEFF Research Database (Denmark)

Kelso, A; Owens, T

1988-01-01

A method has been developed to measure the production by single activated T lymphocytes of two hemopoietic growth factors, granulocyte-macrophage CSF (GM-CSF) and multipotential CSF (multi-CSF or IL-3). When individual cells of the L3T4 (CD4)+ F23.1+ T cell clone E9.D4 were transferred by microma......A method has been developed to measure the production by single activated T lymphocytes of two hemopoietic growth factors, granulocyte-macrophage CSF (GM-CSF) and multipotential CSF (multi-CSF or IL-3). When individual cells of the L3T4 (CD4)+ F23.1+ T cell clone E9.D4 were transferred...... by micromanipulation into wells coated with the monoclonal anti-T cell receptor antibody F23.1, up to 90% of cells produced CSF as detected by CSF-dependent hemopoietic cell lines. Production occurred in the absence of proliferation and did not require the addition of accessory cells or IL-2. Both the frequency of CSF......-producing cells and the average production per positive cell depended on the density of the immobilized stimulating ligand, indicating that the response of each cell is not an all-or-none phenomenon but varies with the strength of stimulation. Individual cells of the clone varied over a 100-fold range...

Internalization mechanisms of the epidermal growth factor receptor after activation with different ligands

DEFF Research Database (Denmark)

Henriksen, Lasse; Grandal, Michael Vibo; Knudsen, Stine Louise Jeppe

2013-01-01

after ligand activation focuses on the effect of epidermal growth factor (EGF) and transforming growth factor-α (TGF-α). For a long time it was believed that clathrin-mediated endocytosis was the major pathway for internalization of the receptor, but recent work suggests that different pathways exist....... Here we show that clathrin ablation completely inhibits internalization of EGF- and TGF-α-stimulated receptor, however the inhibition of receptor internalization in cells treated with heparin-binding EGF-like growth factor (HB-EGF) or betacellulin (BTC) was only partial. In contrast, clathrin knockdown...... fully inhibits EGFR degradation after all ligands tested. Furthermore, inhibition of dynamin function blocked EGFR internalization after stimulation with all ligands. Knocking out a number of clathrin-independent dynamin-dependent pathways of internalization had no effect on the ligand...

Antitumor efficacy of triple monoclonal antibody inhibition of epidermal growth factor receptor (EGFR) with MM151 in EGFR-dependent and in cetuximab-resistant human colorectal cancer cells

Science.gov (United States)

Napolitano, Stefania; Martini, Giulia; Martinelli, Erika; Della Corte, Carminia Maria; Morgillo, Floriana; Belli, Valentina; Cardone, Claudia; Matrone, Nunzia; Ciardiello, Fortunato; Troiani, Teresa

2017-01-01

Purpose We investigated the effect of triple monoclonal antibody inhibition of EGFR to overcome acquired resistance to first generation of anti-EGFR inhibitors. Experimental design MM151 is a mixture of three different monoclonal IgG1 antibodies directed toward three different, non-overlapping, epitopes of the EGFR. We performed an in vivo study by using human CRC cell lines (SW48, LIM 1215 and CACO2) which are sensitive to EGFR inhibitors, in order to evaluate the activity of MM151 as compared to standard anti-EGFR mAbs, such as cetuximab, as single agent or in a sequential strategy of combination MM151 with irinotecan (induction therapy) followed by MM151 with a selective MEK1/2 inhibitor (MEKi) (maintenance therapy). Furthermore, the ability of MM151 to overcome acquired resistance to cetuximab has been also evaluated in cetuximab-refractory CRC models. Results MM151 shown stronger antitumor activity as compared to cetuximab. The maintenance treatment with MM151 plus MEKi resulted the most effective therapeutic modality. In fact, this combination caused an almost complete suppression of tumor growth in SW48, LIM 1215 and CACO2 xenografts model at 30 week. Moreover, in this treatment group, mice with no evidence of tumor were more than double as compared to single agent treated mice. Its superior activity has also been demonstrated, in cetuximab-refractory CRC models. Conclusions These results provide experimental evidence that more efficient and complete EGFR blockade may determine better antitumor activity and could contribute to prevent and/or overcome acquired resistance to EGFR inhibitors. PMID:29137301

Pharmacokinetics and safety in rhesus monkeys of a monoclonal antibody-GDNF fusion protein for targeted blood-brain barrier delivery.

Science.gov (United States)

Pardridge, William M; Boado, Ruben J

2009-10-01

Glial-derived neurotrophic factor (GDNF) is a potential therapy for stroke, Parkinson's disease, or drug addiction. However, GDNF does not cross the blood-brain barrier (BBB). GDNF is re-engineered as a fusion protein with a chimeric monoclonal antibody (MAb) to the human insulin receptor (HIR), which acts as a molecular Trojan horse to deliver the GDNF across the BBB. The pharmacokinetics (PK), toxicology, and safety pharmacology of the HIRMAb-GDNF fusion protein were investigated in Rhesus monkeys. The fusion protein was administered as an intravenous injection at doses up to 50 mg/kg over a 60 h period to 56 Rhesus monkeys. The plasma concentration of the HIRMAb-GDNF fusion protein was measured with a 2-site sandwich ELISA. No adverse events were observed in a 2-week terminal toxicology study, and no neuropathologic changes were observed. The PK analysis showed a linear relationship between plasma AUC and dose, a large systemic volume of distribution, as well as high clearance rates of 8-10 mL/kg/min. A no-observable-adverse-effect level is established in the Rhesus monkey for the acute administration of the HIRMAb-GDNF fusion protein. The fusion protein targeting the insulin receptor has a PK profile similar to a classical small molecule.

Production of monoclonal antibodies against Mycobacterium leprae and armadillo-derived mycobacteria

NARCIS (Netherlands)

Kolk, A. H.; Ho, M. L.; Klatser, P. R.; Eggelte, T. A.; Portaels, F.

1985-01-01

Six monoclonal antibodies to Mycobacterium leprae and armadillo-derived mycobacteria were produced. The monoclonal antibodies were characterized by an immunofluorescence assay using 22 mycobacterial strains. One monoclonal antibody, F47-21-3, reacted only with M. leprae; two, F45-9 and F45-15,

Molecular imaging of rheumatoid arthritis by radiolabelled monoclonal antibodies: new imaging strategies to guide molecular therapies

Energy Technology Data Exchange (ETDEWEB)

Malviya, G.; Dierckx, R.A. [Department of Nuclear Medicine and Molecular Imaging, University Medical Centre Groningen, University of Groningen (Netherlands); Conti, F. [Rheumatology Unit, I Faculty of Medicine and Surgery, Sapienza University of Rome (Italy); Chianelli, M. [Department of Nuclear Medicine and Molecular Imaging, University Medical Centre Groningen, University of Groningen (Netherlands); Unit of Nuclear Medicine, Regina apostolorum Hospital, Albano, Rome (Italy); Scopinaro, F. [Nuclear Medicine Department, Sapienza University of Rome, St. Andrea Hospital, Rome (Italy); Signore, A. [Department of Nuclear Medicine and Molecular Imaging, University Medical Centre Groningen, University of Groningen (Netherlands); Nuclear Medicine Department, Sapienza University of Rome, St. Andrea Hospital, Rome (Italy)

2010-02-15

The closing of the last century opened a wide variety of approaches for inflammation imaging and treatment of patients with rheumatoid arthritis (RA). The introduction of biological therapies for the management of RA started a revolution in the therapeutic armamentarium with the development of several novel monoclonal antibodies (mAbs), which can be murine, chimeric, humanised and fully human antibodies. Monoclonal antibodies specifically bind to their target, which could be adhesion molecules, activation markers, antigens or receptors, to interfere with specific inflammation pathways at the molecular level, leading to immune-modulation of the underlying pathogenic process. These new generation of mAbs can also be radiolabelled by using direct or indirect method, with a variety of nuclides, depending upon the specific diagnostic application. For studying rheumatoid arthritis patients, several monoclonal antibodies and their fragments, including anti-TNF-{alpha}, anti-CD20, anti-CD3, anti-CD4 and anti-E-selectin antibody, have been radiolabelled mainly with {sup 99m}Tc or {sup 111}In. Scintigraphy with these radiolabelled antibodies may offer an exciting possibility for the study of RA patients and holds two types of information: (1) it allows better staging of the disease and diagnosis of the state of activity by early detection of inflamed joints that might be difficult to assess; (2) it might provide a possibility to perform 'evidence-based biological therapy' of arthritis with a view to assessing whether an antibody will localise in an inflamed joint before using the same unlabelled antibody therapeutically. This might prove particularly important for the selection of patients to be treated since biological therapies can be associated with severe side-effects and are considerably expensive. This article reviews the use of radiolabelled mAbs in the study of RA with particular emphasis on the use of different radiolabelled monoclonal antibodies for

Molecular imaging of rheumatoid arthritis by radiolabelled monoclonal antibodies: new imaging strategies to guide molecular therapies

International Nuclear Information System (INIS)

Malviya, G.; Dierckx, R.A.; Conti, F.; Chianelli, M.; Scopinaro, F.; Signore, A.

2010-01-01

The closing of the last century opened a wide variety of approaches for inflammation imaging and treatment of patients with rheumatoid arthritis (RA). The introduction of biological therapies for the management of RA started a revolution in the therapeutic armamentarium with the development of several novel monoclonal antibodies (mAbs), which can be murine, chimeric, humanised and fully human antibodies. Monoclonal antibodies specifically bind to their target, which could be adhesion molecules, activation markers, antigens or receptors, to interfere with specific inflammation pathways at the molecular level, leading to immune-modulation of the underlying pathogenic process. These new generation of mAbs can also be radiolabelled by using direct or indirect method, with a variety of nuclides, depending upon the specific diagnostic application. For studying rheumatoid arthritis patients, several monoclonal antibodies and their fragments, including anti-TNF-α, anti-CD20, anti-CD3, anti-CD4 and anti-E-selectin antibody, have been radiolabelled mainly with 99m Tc or 111 In. Scintigraphy with these radiolabelled antibodies may offer an exciting possibility for the study of RA patients and holds two types of information: (1) it allows better staging of the disease and diagnosis of the state of activity by early detection of inflamed joints that might be difficult to assess; (2) it might provide a possibility to perform 'evidence-based biological therapy' of arthritis with a view to assessing whether an antibody will localise in an inflamed joint before using the same unlabelled antibody therapeutically. This might prove particularly important for the selection of patients to be treated since biological therapies can be associated with severe side-effects and are considerably expensive. This article reviews the use of radiolabelled mAbs in the study of RA with particular emphasis on the use of different radiolabelled monoclonal antibodies for therapy decision-making and

Characterization of a receptor for human monocyte-derived neutrophil chemotactic factor/interleukin-8

International Nuclear Information System (INIS)

Grob, P.M.; David, E.; Warren, T.C.; DeLeon, R.P.; Farina, P.R.; Homon, C.A.

1990-01-01

Monocyte-derived neutrophil chemotactic factor/interleukin-8 (MDNCF/IL-8) is an 8,000-dalton protein produced by monocytes which exhibits activity as a chemoattractant for neutrophils with maximal activity achieved at a concentration of 50 ng/ml. This polypeptide has been iodinated by chloramine-T methodology (350 Ci/mM), and specific receptors for MDNCF/IL-8 have been detected on human neutrophils, U937 cells, THP-1 cells, and dimethyl sulfoxide-differentiated HL-60 cells. The binding of MDNCF/IL-8 to human neutrophils is not inhibited by interleukin-1 alpha, tumor necrosis factor-alpha, insulin, or epidermal growth factor. In addition, chemoattractants such as C5a, fMet-Leu-Phe, leukotriene B4, and platelet-activating factor fail to inhibit binding, suggesting that MDNCF/IL-8 utilizes a unique receptor. The receptor for MDNCF/IL-8 is apparently glycosylated since ligand binding is inhibited by the presence of wheat germ agglutinin, a lectin with a binding specificity for N-acetylglucosamine and neuraminic acid. Steady state binding experiments indicate Kd values of 4 and 0.5 nM and receptor numbers of 75,000 and 7,400 for human neutrophils and differentiated HL-60 cells, respectively. 125I-MDNCF/IL-8 bound to human neutrophils is rapidly internalized and subsequently released from cells as trichloroacetic acid-soluble radioactivity. Affinity labeling experiments suggest that the human neutrophil MDNCF/IL-8 receptor exhibits a mass of approximately 58,000 daltons

Virus-resembling nano-structures for near infrared fluorescence imaging of ovarian cancer HER2 receptors

Science.gov (United States)

Guerrero, Yadir A.; Bahmani, Baharak; Singh, Sheela P.; Vullev, Valentine I.; Kundra, Vikas; Anvari, Bahman

2015-10-01

Ovarian cancer remains the dominant cause of death due to malignancies of the female reproductive system. The capability to identify and remove all tumors during intraoperative procedures may ultimately reduce cancer recurrence, and lead to increased patient survival. The objective of this study is to investigate the effectiveness of an optical nano-structured system for targeted near infrared (NIR) imaging of ovarian cancer cells that over-express the human epidermal growth factor receptor 2 (HER2), an important biomarker associated with ovarian cancer. The nano-structured system is comprised of genome-depleted plant-infecting brome mosaic virus doped with NIR chromophore, indocyanine green, and functionalized at the surface by covalent attachment of monoclonal antibodies against the HER2 receptor. We use absorption and fluorescence spectroscopy, and dynamic light scattering to characterize the physical properties of the constructs. Using fluorescence imaging and flow cytometry, we demonstrate the effectiveness of these nano-structures for targeted NIR imaging of HER2 receptors in vitro. These functionalized nano-materials may provide a platform for NIR imaging of ovarian cancer.

Virus-resembling nano-structures for near infrared fluorescence imaging of ovarian cancer HER2 receptors

International Nuclear Information System (INIS)

Guerrero, Yadir A; Bahmani, Baharak; Vullev, Valentine I; Anvari, Bahman; Singh, Sheela P; Kundra, Vikas

2015-01-01

Ovarian cancer remains the dominant cause of death due to malignancies of the female reproductive system. The capability to identify and remove all tumors during intraoperative procedures may ultimately reduce cancer recurrence, and lead to increased patient survival. The objective of this study is to investigate the effectiveness of an optical nano-structured system for targeted near infrared (NIR) imaging of ovarian cancer cells that over-express the human epidermal growth factor receptor 2 (HER2), an important biomarker associated with ovarian cancer. The nano-structured system is comprised of genome-depleted plant-infecting brome mosaic virus doped with NIR chromophore, indocyanine green, and functionalized at the surface by covalent attachment of monoclonal antibodies against the HER2 receptor. We use absorption and fluorescence spectroscopy, and dynamic light scattering to characterize the physical properties of the constructs. Using fluorescence imaging and flow cytometry, we demonstrate the effectiveness of these nano-structures for targeted NIR imaging of HER2 receptors in vitro. These functionalized nano-materials may provide a platform for NIR imaging of ovarian cancer. (paper)

MUSCARINIC ACETYLCHOLINE RECEPTOR-EXPRESSION IN ASTROCYTES IN THE CORTEX OF YOUNG AND AGED RATS

NARCIS (Netherlands)

VANDERZEE, EA; DEJONG, GI; STROSBERG, AD; LUITEN, PGM

The present report describes the cellular and subcellular distribution pattern of immunoreactivity to M35, a monoclonal antibody raised against purified muscarinic acetylcholine receptor protein, in astrocytes in the cerebral cortex of young and aged rats. Most M35-positive astrocytes were localized

Analysis of monoclonal antibodies reactive with molecules upregulated or expressed only on activated lymphocytes.

Science.gov (United States)

Davis, W C; Naessens, J; Brown, W C; Ellis, J A; Hamilton, M J; Cantor, G H; Barbosa, J I; Ferens, W; Bohach, G A

1996-08-01

Monoclonal antibodies potentially specific for antigens expressed or upregulated on activated leukocytes were selected for further analysis from the panel submitted to the third international workshop on ruminant leukocyte antigens. The kinetics of expression of these activation antigens on resting peripheral mononuclear cells (PBMC) and PBMC stimulated with concanavalin A or staphylococcal superantigen SECI for 4, 24 or 96 h were compared, as well as their appearance on various subsets of cells. For some of them, a molecular mass could be determined after immunoprecipitation from radio-labeled, lectin-stimulated cells. Based on the results from the clustering, kinetic studies and biochemical data, evidence was gathered for assigning two additional mAbs to cluster BoCD25 (IL-2 receptor) and two mAbs to cluster BoCD71 (transferrin receptor). Four mAbs recognized an early activation antigen predominantly expressed on gamma delta T cells in short-term cultures. A number of other activation antigens were further characterized.

Identification of a human monoclonal antibody to replace equine diphtheria antitoxin for treatment of diphtheria intoxication.

Science.gov (United States)

Sevigny, Leila M; Booth, Brian J; Rowley, Kirk J; Leav, Brett A; Cheslock, Peter S; Garrity, Kerry A; Sloan, Susan E; Thomas, William; Babcock, Gregory J; Wang, Yang

2013-11-01

Diphtheria antitoxin (DAT) has been the cornerstone of the treatment of Corynebacterium diphtheriae infection for more than 100 years. Although the global incidence of diphtheria has declined steadily over the last quarter of the 20th century, the disease remains endemic in many parts of the world, and significant outbreaks still occur. DAT is an equine polyclonal antibody that is not commercially available in the United States and is in short supply globally. A safer, more readily available alternative to DAT would be desirable. In the current study, we obtained human monoclonal antibodies (hMAbs) directly from antibody-secreting cells in the circulation of immunized human volunteers. We isolated a panel of diverse hMAbs that recognized diphtheria toxoid, as well as a variety of recombinant protein fragments of diphtheria toxin. Forty-five unique hMAbs were tested for neutralization of diphtheria toxin in in vitro cytotoxicity assays with a 50% effective concentration of 0.65 ng/ml for the lead candidate hMAb, 315C4. In addition, 25 μg of 315C4 completely protected guinea pigs from intoxication in an in vivo lethality model, yielding an estimated relative potency of 64 IU/mg. In comparison, 1.6 IU of DAT was necessary for full protection from morbidity and mortality in this model. We further established that our lead candidate hMAb binds to the receptor-binding domain of diphtheria toxin and physically blocks the toxin from binding to the putative receptor, heparin-binding epidermal growth factor-like growth factor. The discovery of a specific and potent human neutralizing antibody against diphtheria toxin holds promise as a potential therapeutic.

Association of coatomer proteins with the beta-receptor for platelet-derived growth factor

DEFF Research Database (Denmark)

Hansen, Klaus; Rönnstrand, L; Rorsman, C

1997-01-01

The nonreceptor tyrosine kinase Src binds to and is activated by the beta-receptor for platelet-derived growth factor (PDGF). The interaction leads to Src phosphorylation of Tyr934 in the kinase domain of the receptor. In the course of the functional characterization of this phosphorylation, we...... of intracellular vesicle transport. In order to explore the functional significance of the interaction between alpha- and beta'-COP and the PDGF receptor, a receptor mutant was made in which the conserved histidine residue 928 was mutated to an alanine residue. The mutant receptor, which was unable to bind alpha...

Adenovirus E4-ORF1 Dysregulates Epidermal Growth Factor and Insulin/Insulin-Like Growth Factor Receptors To Mediate Constitutive Myc Expression

OpenAIRE

Kong, Kathleen; Kumar, Manish; Taruishi, Midori; Javier, Ronald T.

2015-01-01

The E4-ORF1 protein encoded by human adenovirus stimulates viral replication in human epithelial cells by binding and activating cellular phosphatidylinositol 3-kinase (PI3K) at the plasma membrane and cellular Myc in the nucleus. In this study, we showed that E4-ORF1 hijacks the tyrosine kinase activities of cellular epidermal growth factor receptor (EGFR) and insulin receptor (InsR)/insulin-like growth factor receptor 1 (IGF1R), as well as the lipid kinase activity of PI3K, to mediate const...

Soluble tumor necrosis factor receptor-1 in preterm infants with chronic lung disease.

Science.gov (United States)

Sato, Miho; Mori, Masaaki; Nishimaki, Shigeru; An, Hiromi; Naruto, Takuya; Sugai, Toshiyuki; Shima, Yoshio; Seki, Kazuo; Yokota, Shumpei

2010-04-01

It is clear that inflammation plays an important role in developing chronic lung disease in preterm infants. The purpose of the present study is to investigate changes of serum soluble tumor necrosis factor receptor-1 levels over time in infants with chronic lung disease. The serum levels of soluble tumor necrosis factor receptor-1 were measured after delivery, and at 7, 14, 21 and 28 days of age in 10 infants with chronic lung disease and in 18 infants without chronic lung disease. The serum level of soluble tumor necrosis factor receptor-1 was significantly higher in infants with chronic lung disease than in infants without chronic lung disease after delivery. The differences between these two groups remained up to 28 days of age. Prenatal inflammation with persistence into postnatal inflammation may be involved in the onset of chronic lung disease.

IGF-II receptors and IGF-II-stimulated glucose transport in human fat cells

International Nuclear Information System (INIS)

Sinha, M.K.; Buchanan, C.; Raineri-Maldonado, C.; Khazanie, P.; Atkinson, S.; DiMarchi, R.; Caro, J.F.

1990-01-01

Insulin-like growth factor II (IGF-II) receptors have been described in rat but not in human adipocytes. In both species, IGF-II has been reported to stimulate glucose transport by interacting with the insulin receptor. In this study, we have unequivocally demonstrated the presence of IGF-II receptors in human adipocytes. 125I-labeled IGF-II specifically binds to intact adipocytes, membranes, and lectin-purified detergent solubilized extracts. Through the use of 0.5 mM disuccinimidyl suberate, 125I-IGF-II is cross-linked to a 260-kDa protein that is identified as the IGF-II receptor by displacement experiments with unlabeled IGF-II, IGF-I, and insulin and either by immunoprecipitation or by Western blot analysis with mannose 6-phosphate receptor antibodies. The concentrations of IGF-II required for half-maximal and maximal stimulation of glucose transport in human adipocytes are 35 and 100 times more than that of insulin. The possibility of IGF-II stimulating glucose transport by interacting predominantly with the insulin receptor is suggested by the following: (1) the concentration of IGF-II that inhibits half of insulin binding is only 20 times more than that of insulin; (2) the lack of an additive effect of IGF-II and insulin for maximal stimulation of glucose transport; (3) the ability of monoclonal insulin receptor antibodies to decrease glucose transport stimulated by submaximal concentrations of both IGF-II and insulin; and (4) the ability of IGF-II to stimulate insulin receptor autophosphorylation albeit at a reduced potency when compared with insulin

Hierarchical classification strategy for Phenotype extraction from epidermal growth factor receptor endocytosis screening

NARCIS (Netherlands)

L. Cao (Lu); M. Graauw (Marjo de); K. Yan (Kuan); L.C.J. Winkel (Leah C.J.); F.J. Verbeek (Fons)

2016-01-01

textabstractBackground: Endocytosis is regarded as a mechanism of attenuating the epidermal growth factor receptor (EGFR) signaling and of receptor degradation. There is increasing evidence becoming available showing that breast cancer progression is associated with a defect in EGFR endocytosis. In

Emerging growth factor receptor antagonists for the treatment of renal cell carcinoma.

Science.gov (United States)

Zahoor, Haris; Rini, Brian I

2016-12-01

The landscape of systemic treatment for metastatic renal cell carcinoma (RCC) has dramatically changed with the introduction of targeted agents including vascular endothelial growth factor (VEGF) inhibitors. Recently, multiple new agents including growth factor receptor antagonists and a checkpoint inhibitor were approved for the treatment of refractory metastatic RCC based on encouraging benefit shown in clinical trials. Areas covered: The background and biological rationale of existing treatment options including a brief discussion of clinical trials which led to their approval, is presented. This is followed by reviewing the limitations of these therapeutic options, medical need to develop new treatments and major goals of ongoing research. We then discuss two recently approved growth factor receptor antagonists i.e. cabozantinib and lenvatinib, and a recently approved checkpoint inhibitor, nivolumab, and issues pertaining to drug development, and future directions in treatment of metastatic RCC. Expert opinion: Recently approved growth factor receptor antagonists have shown encouraging survival benefit but associated drug toxicity is a major issue. Nivolumab, a programmed death 1 (PD-1) checkpoint inhibitor, has similarly shown survival benefit and is well tolerated. With multiple options now available in this patient population, the right sequence of these agents remains to be determined.

Monoclonal gammopathy: a diagnosis for to keep in mind

International Nuclear Information System (INIS)

Howland Alvarez, Ivon; Figueredo Peguero, Yrving; Luna Conde, Clara

2011-01-01

How to identify monoclonal gammopathies at risk for progression has been studied for the last year. 40 patients were studied in which a monoclonal band had been detected, in some of the cases de novo. The electrophoresis was performed in the Hydrasys system. Of the total of electrophoresis carried out, the 14% was monoclonal gammopathy. In 36% a diagnostic assumption was not stated. Most frequent diagnosis in the group of patients with a diagnosis was multiple myeloma. Average age of patients was 61.5 years and there were differences among percentages for sex

Nature of the bifunctional chelating agent used for radioimmunotherapy with yttrium-88 monoclonal antibodies: critical factors in determining in vivo survival and organ toxicity

Energy Technology Data Exchange (ETDEWEB)

Kozak, R.W.; Raubitschek, A.; Mirzadeh, S.; Brechbiel, M.W.; Junghaus, R.; Gansow, O.A.; Waldmann, T.A. (Center for Biologics Evaluation and Research, FDA, Bethesda, MD (USA))

1989-05-15

One factor that is critical to the potential effectiveness of radioimmunotherapy is the design of radiometal-chelated antibodies that will be stable in vivo. Stability in vivo depends on the condition that both the chelate linkage and radiolabeling procedures not alter antibody specificity and biodistribution. In addition, synthesis and selection of the chelating agent is critical for each radiometal in order to prevent inappropriate release of the radiometal in vivo. In the present study, we compare the in vivo stability of seven radioimmunoconjugates that use different polyaminocarboxylate chelating agents to complex yttrium-88 to the mouse anti-human interleukin-2 receptor monoclonal antibody, anti-Tac. Chelate linkage and radiolabeling procedures did not alter the immunospecificity of anti-Tac. In order to assess whether yttrium was inappropriately released from the chelate-coupled antibody in vivo, iodine-131-labeled and yttrium-88 chelate-coupled antibodies were simultaneously administered to the same animals to correlate the decline in yttrium and radioiodinated antibody activity. The four stable yttrium-88 chelate-coupled antibodies studied displayed similar iodine-131 and yttrium-88 activity, indicating minimal elution of yttrium-88 from the complex. In contrast, the unstable yttrium-88 chelate-coupled antibodies had serum yttrium-88 activities that declined much more rapidly than their iodine-131 activities, suggesting loss of the radiolabel yttrium-88 from the chelate. Furthermore, high rates of yttrium-88 elution correlated with deposition in bone. Four chelating agents emerged as promising immunotherapeutic reagents: isothiocyanate benzyl DTPA and its derivatives 1B3M, MX, and 1M3B.

Studies of a murine monoclonal antibody directed against DARC: reappraisal of its specificity.

Directory of Open Access Journals (Sweden)

Dorota Smolarek

Full Text Available Duffy Antigen Receptor for Chemokines (DARC plays multiple roles in human health as a blood group antigen, a receptor for chemokines and the only known receptor for Plasmodium vivax merozoites. It is the target of the murine anti-Fy6 monoclonal antibody 2C3 which binds to the first extracellular domain (ECD1, but exact nature of the recognized epitope was a subject of contradictory reports. Here, using a set of complex experiments which include expression of DARC with amino acid substitutions within the Fy6 epitope in E. coli and K562 cells, ELISA, surface plasmon resonance (SPR and flow cytometry, we have resolved discrepancies between previously published reports and show that the basic epitope recognized by 2C3 antibody is 22FEDVW26, with 22F and 26W being the most important residues. In addition, we demonstrated that 30Y plays an auxiliary role in binding, particularly when the residue is sulfated. The STD-NMR studies performed using 2C3-derived Fab and synthetic peptide corroborated most of these results, and together with the molecular modelling suggested that 25V is not involved in direct interactions with the antibody, but determines folding of the epitope backbone.

The under-appreciated promiscuity of the epidermal growth factor receptor family.

Directory of Open Access Journals (Sweden)

Sean P Kennedy

2016-08-01

Full Text Available Each member of the epidermal growth factor receptor (EGFR family plays a key role in normal development, homeostasis and a variety of pathophysiological conditions, most notably in cancer. According to the prevailing dogma, these four receptor tyrosine kinases (RTKs; EGFR, ERBB2, ERBB3 and ERBB4 function exclusively through the formation of homodimers and heterodimers within the EGFR family. These combinatorial receptor interactions are known to generate increased interactome diversity and therefore influence signalling output, subcellular localization and function of the heterodimer. This molecular plasticity is also thought to play a role in the development of resistance towards targeted cancer therapies aimed at these known oncogenes. Interestingly, many studies now challenge this dogma and suggest that the potential for EGFR family receptors to interact with more distantly related RTKs is much greater than currently appreciated. Here we discuss how the promiscuity of these oncogenic receptors may lead to the formation of many unexpected receptor pairings and the significant implications for the efficiency of many targeted cancer therapies.

Immunoautoradiographic analysis of epidermal growth factor receptors: a sensitive method for the in situ identification of receptor proteins and for studying receptor specificity

International Nuclear Information System (INIS)

Fernandez-Pol, J.A.

1982-01-01

The use of an immunoautoradiographic system for the detection and analysis of epidermal growth factor (EGF) receptors in human epidermoid carcinoma A-431 cells is reported. By utilizing this technique, the interaction between EGF and its membrane receptor in A-431 cells can be rapidly visualized. The procedure is simple, rapid, and very sensitive, and it provides conclusive evidence that the 150K dalton protein is the receptor fo EGF in A-431 cells. In summary, the immunoautoradiographic procedure brings to the analysis of hormone rceptor proteins the power that the radioimmunoassay technique has brought to the analysis of hormones. Thus, this assay system is potentially applicable in a wide spectrum in many fields of nuclear medicine and biology

A transcription factor active on the epidermal growth factor receptor gene

International Nuclear Information System (INIS)

Kageyama, R.; Merlino, G.T.; Pastan, I.

1988-01-01

The authors have developed an in vitro transcription system for the epidermal growth factor receptor (EGFR) oncogene by using nuclear extracts of A431 human epidermoid carcinoma cells, which overproduce EGFR. They found that a nuclear factor, termed EGFR-specific transcription factor (ETF), specifically stimulated EGFR transcription by 5- to 10-fold. In this report, ETF, purified by using sequence-specific oligonucleotide affinity chromatography, is shown by renaturing material eluted from a NaDodSO 4 /polyacrylamide gel to be a protein with a molecular mass of 120 kDa. ETF binds to the promoter region, as measured by DNase I footprinting and gel-mobility-shift assays, and specifically stimulates the transcription of the EGFR gene in a reconstituted in vitro transcription system. These results suggest that ETF could play a role in the overexpression of the cellular oncogene EGFR

New monoclonal antibodies to rat testicular antigen, TEC-21

Czech Academy of Sciences Publication Activity Database

Hálová, Ivana; Dráberová, Lubica; Dráber, Petr

2001-01-01

Roč. 47, č. 5 (2001), s. 180-182 ISSN 0015-5500 R&D Projects: GA ČR GV312/96/K205; GA ČR GA204/00/0204; GA ČR GA310/00/0205; GA AV ČR IAA5052005; GA AV ČR IAA7052006; GA MŠk LN00A026 Institutional research plan: CEZ:AV0Z5052915 Keywords : monoclonal antibody * GPI-anchored * testicular antigen Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.519, year: 2001

α-transforming growth factor secreted by untransformed bovine anterior pituitary cells in culture. II. Identification using a sequence-specific monoclonal antibody

International Nuclear Information System (INIS)

Kobrin, M.S.; Samsoondar, J.; Kudlow, J.E.

1986-01-01

Untransformed bovine anterior pituitary cells cultured in serum-free defined medium secrete an epidermal growth factor (EGF)-like peptide with an amino acid composition similar to rat or human α-transforming growth factor (αTGF). To further characterize the bovine pituitary αTGF, it was compared to a human αTGF partially purified from the conditioned medium of a human melanoma cell line. An anti-αTGF monoclonal antibody, MF9, was produced from hybridomas derived from mice immunized with a 17-residue synthetic peptide corresponding to the carboxyl-terminal sequence of rat αTGF. The hybridoma supernatants were initially screened for the ability to immunoprecipitate 125 I-peptide and then tested for recognition of human αTGF. Only 2 of 36 antipeptide antibodies recognized the native αTGF. The binding of 125 I-peptide to MF9 was displaced by human αTGF but not by EGF. Bovine pituitary αTGF also displaced the binding of 125 I-peptide to MF9 in a similar manner to human αTGF. Both iodinated human and bovine pituitary αTGF were immunoprecipitated by MF9 whereas 125 I-EGF was not. Tryptic digests of both 125 I-αTGFs chromatographed to give a single, indistinguishable peak of iodinated material on a reverse-phase C 18 high performance liquid chromatography column when eluted with two different solvent systems, suggesting the generation of a single and identical tyrosine-containing tryptic peptide from both αTGFs. The comparisons of the bovine pituitary and human melanoma αTGF using a sequence-specific monoclonal antibody and peptide mapping suggest that these αTGFs are related and that αTGF production is not limited to transformed or fetal sources

Enzyme immunoassay of oestrogen receptors in needle biopsies from human liver

DEFF Research Database (Denmark)

Becker, U; Andersen, J; Poulsen, H S

1991-01-01

For quantitative assessments of sex hormone receptors in liver tissue, ligand binding assays are inconvenient, as they require large biopsies (0.5-1.0 g). The present study shows that it is possible to measure oestrogen receptors (ER) quantitatively in needle biopsy specimens as small as 10 mg...... by modifications of a commercial enzyme immunoassay employing monoclonal antibodies. Sucrose gradient centrifugation and the dextran charcoal method served as reference methods. A consecutive series of needle biopsies from patients suspected of liver disease were investigated. The biopsies (n = 37) had a median...

Assay for the specificity of monoclonal antibodies in crossed immunoelectrophoresis

DEFF Research Database (Denmark)

Skjødt, K; Schou, C; Koch, C

1984-01-01

A method is described based on crossed immunoelectrophoresis of a complex antigen mixture in agarose gel followed by incubation of the gel with the monoclonal antibody. The bound monoclonal antibody is detected by the use of a secondary enzyme-labelled antibody. Using this technique we have been ...... I molecules. In other experiments using the same technique we demonstrated the reaction of a monoclonal antibody specific for chicken Ig light chains. Udgivelsesdato: 1984-Aug-3...

Distribution of corticotropin-releasing factor receptors in primate brain

International Nuclear Information System (INIS)

Millan, M.A.; Jacobowitz, D.M.; Hauger, R.L.; Catt, K.J.; Aguilera, G.

1986-01-01

The distribution and properties of receptors for corticotropin-releasing factor (CRF) were analyzed in the brain of cynomolgus monkeys. Binding of [ 125 I]tyrosine-labeled ovine CRF to frontal cortex and amygdala membrane-rich fractions was saturable, specific, and time- and temperature-dependent, reaching equilibrium in 30 min at 23 0 C. Scatchard analysis of the binding data indicated one class of high-affinity sites with a K/sub d/ of 1 nM and a concentration of 125 fmol/mg. As in the rat pituitary and brain, CRF receptors in monkey cerebral cortex and amygdala were coupled to adenylate cyclase. Autoradiographic analysis of specific CRF binding in brain sections revealed that the receptors were widely distributed in the cerebral cortex and limbic system. Receptor density was highest in the pars tuberalis of the pituitary and throughout the cerebral cortex, specifically in the prefrontal, frontal, orbital, cingulate, insular, and temporal areas, and in the cerebellar cortex. A low binding density was present in the superior colliculus, locus coeruleus, substantia gelatinosa, preoptic area, septal area, and bed nucleus of the stria terminalis. These data demonstrate that receptors for CRF are present within the primate brain at areas related to the central control of visceral function and behavior, suggesting that brain CRF may serve as a neurotransmitter in the coordination of endocrine and neural mechanisms involved in the response to stress

EphA2 is a functional receptor for the growth factor progranulin.

Science.gov (United States)

Neill, Thomas; Buraschi, Simone; Goyal, Atul; Sharpe, Catherine; Natkanski, Elizabeth; Schaefer, Liliana; Morrione, Andrea; Iozzo, Renato V

2016-12-05

Although the growth factor progranulin was discovered more than two decades ago, the functional receptor remains elusive. Here, we discovered that EphA2, a member of the large family of Ephrin receptor tyrosine kinases, is a functional signaling receptor for progranulin. Recombinant progranulin bound with high affinity to EphA2 in both solid phase and solution. Interaction of progranulin with EphA2 caused prolonged activation of the receptor, downstream stimulation of mitogen-activated protein kinase and Akt, and promotion of capillary morphogenesis. Furthermore, we found an autoregulatory mechanism of progranulin whereby a feed-forward loop occurred in an EphA2-dependent manner that was independent of the endocytic receptor sortilin. The discovery of a functional signaling receptor for progranulin offers a new avenue for understanding the underlying mode of action of progranulin in cancer progression, tumor angiogenesis, and perhaps neurodegenerative diseases. © 2016 Neill et al.

Signaling by Kit protein-tyrosine kinase--the stem cell factor receptor.

Science.gov (United States)

Roskoski, Robert

2005-11-11

Signaling by stem cell factor and Kit, its receptor, plays important roles in gametogenesis, hematopoiesis, mast cell development and function, and melanogenesis. Moreover, human and mouse embryonic stem cells express Kit transcripts. Stem cell factor exists as both a soluble and a membrane-bound glycoprotein while Kit is a receptor protein-tyrosine kinase. The complete absence of stem cell factor or Kit is lethal. Deficiencies of either produce defects in red and white blood cell production, hypopigmentation, and sterility. Gain-of-function mutations of Kit are associated with several human neoplasms including acute myelogenous leukemia, gastrointestinal stromal tumors, and mastocytomas. Kit consists of an extracellular domain, a transmembrane segment, a juxtamembrane segment, and a protein kinase domain that contains an insert of about 80 amino acid residues. Binding of stem cell factor to Kit results in receptor dimerization and activation of protein kinase activity. The activated receptor becomes autophosphorylated at tyrosine residues that serve as docking sites for signal transduction molecules containing SH2 domains. The adaptor protein APS, Src family kinases, and Shp2 tyrosyl phosphatase bind to phosphotyrosine 568. Shp1 tyrosyl phosphatase and the adaptor protein Shc bind to phosphotyrosine 570. C-terminal Src kinase homologous kinase and the adaptor Shc bind to both phosphotyrosines 568 and 570. These residues occur in the juxtamembrane segment of Kit. Three residues in the kinase insert domain are phosphorylated and attract the adaptor protein Grb2 (Tyr703), phosphatidylinositol 3-kinase (Tyr721), and phospholipase Cgamma (Tyr730). Phosphotyrosine 900 in the distal kinase domain binds phosphatidylinositol 3-kinase which in turn binds the adaptor protein Crk. Phosphotyrosine 936, also in the distal kinase domain, binds the adaptor proteins APS, Grb2, and Grb7. Kit has the potential to participate in multiple signal transduction pathways as a result of

Multistep change in epidermal growth factor receptors during spontaneous neoplastic progression in Chinese hamster embryo fibroblasts

International Nuclear Information System (INIS)

Wakshull, E.; Kraemer, P.M.; Wharton, W.

1985-01-01

Whole Chinese hamster embryo lineages have been shown to undergo multistep spontaneous neoplastic progression during serial passage in culture. The authors have studied the binding, internalization, and degradation of 125 I-labeled epidermal growth factor at four different stages of transformation. The whole Chinese hamster embryo cells lost cell surface epidermal growth factor receptors gradually during the course of neoplastic progression until only 10% of the receptor number present in the early-passage cells (precrisis) were retained in the late-passage cells (tumorigenic). No differences in internalization rates, chloroquine sensitivity, or ability to degrade hormone between the various passage levels were seen. No evidence for the presence in conditioned medium of transforming growth factors which might mask or down-regulate epidermal growth factor receptor was obtained. These results suggest that a reduction in cell surface epidermal growth factor receptor might be an early event during spontaneous transformation in whole Chinese hamster embryo cells

Passive vaccination with a human monoclonal antibody: generation of antibodies and studies for efficacy in Bacillus anthracis infections.

Science.gov (United States)

vor dem Esche, Ulrich; Huber, Maria; Zgaga-Griesz, Andrea; Grunow, Roland; Beyer, Wolfgang; Hahn, Ulrike; Bessler, Wolfgang G

2011-07-01

A major difficulty in creating human monoclonal antibodies is the lack of a suitable myeloma cell line to be used for fusion experiments. In order to create fully human monoclonal antibodies for passive immunization, the human mouse heteromyeloma cell line CB-F7 was evaluated. Using this cell line, we generated human monoclonal antibodies against Bacillus anthracis toxin components. Antibodies against protective antigen (PA) and against lethal factor (LF) were obtained using peripheral blood lymphocytes (PBLs) from persons vaccinated with the UK anthrax vaccine. PBL were fused with the cell line CB-F7. We obtained several clones producing PA specific Ig and one clone (hLF1-SAN) producing a monoclonal antibody (hLF1) directed against LF. The LF binding antibody was able to neutralize Anthrax toxin activity in an in vitro neutralization assay, and preliminary in vivo studies in mice also indicated a trend towards protection. We mapped the epitope of the antibody binding to LF by dot blot analysis and ELIFA using 80 synthetic LF peptides of 20 amino acid lengths with an overlapping range of 10 amino acids. Our results suggest the binding of the monoclonal antibody to the peptide regions 121-150 or 451-470 of LF. The Fab-fragment of the antibody hLF1 was cloned in Escherichia coli and could be useful as part of a fully human monoclonal antibody for the treatment of Anthrax infections. In general, our studies show the applicability of the CB-F7 line to create fully human monoclonal antibodies for vaccination. Copyright © 2010 Elsevier GmbH. All rights reserved.

Making Recombinant Monoclonal Antibody And Radiolabelling For Medical Purpose

International Nuclear Information System (INIS)

Nguyen Thi Thu; Duong Van Dong; Vo Thi Cam Hoa; Bui Van Cuong; Chu Van Khoa; Vu Bich Huong; Le Quang Huan

2008-01-01

Recombinant monoclonal antibody labeling with 131 I specific to tumor cell has been studied and prepared for treatment of Hodgkin lymphoma. In this study, a recombinant monoclonal antibody with two specific properties is a hybrid molecule created by coupling an antibody variable fragments with peptide melittin. The gene coding the antibody fragment has been obtained from human synthetic Fv libraries using for panning and screening on populations of lymphocytes fragmented from human blood cells with Hodgkin diseases. The gene encoding peptit melittin has been cloned from honeybee Apis cerana DNA. The gene coding recombinant monoclonal antibody has been expressed in E.coli BL21 (DE3) at 37 o C and was induced with 0.6 mM IPTG. The recombinant compound has been purified by affinity chromatography with HiTrap affinity column. The obtained recombinant monoclonal antibody has showed cytolytic activities when added to cell culture medium for LU cancer cell line with the amount of 100 - 200 mg/ml. This monoclonal antibody is labeled with 131 I using chloramine T procedure. ChT mass for the oxidation of 50 μg monoclonal antibody in 76 MBq was 10 μg. Sodium metabisulfite was used as a reducing agent. Reaction time was above 3 mins. The radiochemical purity was determined using electrophoresis and TLC methods. Radiochemical yield was > 97%. Radiochemical purity after purification was > 99%. Nuclear purity was > 99%. Stability of the label antibody was 12 days. This is the product promise potential used in the diagnostic and therapeutic of Hodgkin lymphoma. (author)

Targeting the TAM Receptors in Leukemia.

Science.gov (United States)

Huey, Madeline G; Minson, Katherine A; Earp, H Shelton; DeRyckere, Deborah; Graham, Douglas K

2016-11-08

Targeted inhibition of members of the TAM (TYRO-3, AXL, MERTK) family of receptor tyrosine kinases has recently been investigated as a novel strategy for treatment of hematologic malignancies. The physiologic functions of the TAM receptors in innate immune control, natural killer (NK) cell differentiation, efferocytosis, clearance of apoptotic debris, and hemostasis have previously been described and more recent data implicate TAM kinases as important regulators of erythropoiesis and megakaryopoiesis. The TAM receptors are aberrantly or ectopically expressed in many hematologic malignancies including acute myeloid leukemia, B- and T-cell acute lymphoblastic leukemia, chronic lymphocytic leukemia, and multiple myeloma. TAM receptors contribute to leukemic phenotypes through activation of pro-survival signaling pathways and interplay with other oncogenic proteins such as FLT3, LYN, and FGFR3. The TAM receptors also contribute to resistance to both cytotoxic chemotherapeutics and targeted agents, making them attractive therapeutic targets. A number of translational strategies for TAM inhibition are in development, including small molecule inhibitors, ligand traps, and monoclonal antibodies. Emerging areas of research include modulation of TAM receptors to enhance anti-tumor immunity, potential roles for TYRO-3 in leukemogenesis, and the function of the bone marrow microenvironment in mediating resistance to TAM inhibition.

Targeting the TAM Receptors in Leukemia

Directory of Open Access Journals (Sweden)

Madeline G. Huey

2016-11-01

Full Text Available Targeted inhibition of members of the TAM (TYRO-3, AXL, MERTK family of receptor tyrosine kinases has recently been investigated as a novel strategy for treatment of hematologic malignancies. The physiologic functions of the TAM receptors in innate immune control, natural killer (NK cell differentiation, efferocytosis, clearance of apoptotic debris, and hemostasis have previously been described and more recent data implicate TAM kinases as important regulators of erythropoiesis and megakaryopoiesis. The TAM receptors are aberrantly or ectopically expressed in many hematologic malignancies including acute myeloid leukemia, B- and T-cell acute lymphoblastic leukemia, chronic lymphocytic leukemia, and multiple myeloma. TAM receptors contribute to leukemic phenotypes through activation of pro-survival signaling pathways and interplay with other oncogenic proteins such as FLT3, LYN, and FGFR3. The TAM receptors also contribute to resistance to both cytotoxic chemotherapeutics and targeted agents, making them attractive therapeutic targets. A number of translational strategies for TAM inhibition are in development, including small molecule inhibitors, ligand traps, and monoclonal antibodies. Emerging areas of research include modulation of TAM receptors to enhance anti-tumor immunity, potential roles for TYRO-3 in leukemogenesis, and the function of the bone marrow microenvironment in mediating resistance to TAM inhibition.

Monoclonal antibodies in animal production : their use in diagnostics and passive immunization

NARCIS (Netherlands)

Booman, P.

1989-01-01

One of the landmarks in immunology was the invention and development of monoclonal antibody-secreting hybridomas by Milstein and his coworkers. The enormous promise of monoclonal antibody technology, which became apparent soon after its discovery, may explain the unusual speed with which monoclonal

Use of commercially available rabbit monoclonal antibodies for immunofluorescence double staining

DEFF Research Database (Denmark)

Bzorek, M.; Stamp, I.M.; Frederiksen, L.

2008-01-01

Immunohistochemistry, that is, the use of polyclonal and monoclonal antibodies to detect cell and tissue antigens at a microscopical level is a powerful tool for both research and diagnostic purposes. Especially in the field of hematologic disease, there is often a need to detect several antigens...... synchronously, and we report here a fast and easy technique for demonstrating more than 1 antigen in 1 slide using immunofluorescence. We have used commercially available rabbit monoclonal antibodies (Cyclin D1, CD3, CD5, CD23, etc.) paired with mouse monoclonal antibodies (CD7, CD20, CD79a, Pax-5, etc.......) for double immunofluorescence labeling on paraffin-embedded tissue sections. Commercially available rabbit monoclonal antibodies in combination with mouse monoclonal antibodies proved useful in double immunofluorescence labeling on paraffin-embedded tissue, and all combinations used yielded excellent results...

Changing the insulin receptor to possess insulin-like growth factor I ligand specificity

International Nuclear Information System (INIS)

Andersen, A.S.; Kjeldsen, T.; Wiberg, F.C.; Christensen, P.M.; Rasmussen, J.S.; Norris, K.; Moeller, K.B.; Moeller, N.P.H.

1990-01-01

To examine the role of the N-terminal part of the insulin-like growth factor I (IGF-I) receptor and insulin receptor in determining ligand specificity, the authors prepared an expression vector encoding a hybrid receptor where exon 1 (encoding the signal peptide and seven amino acids of the α-subunit), exon 2, and exon 3 of the insulin receptor were replaced with the corresponding IGF-I receptor cDNA (938 nucleotides). To allow direct quantitative comparison of the binding capabilities of this hybrid receptor with those of the human IGF-I receptor and the insulin receptor, all three receptors were expressed in baby hamster kidney (BHK) cells as soluble molecules and partially purified before characterization. The hybrid IGF-I/insulin receptor bound IGF-I with an affinity comparable to that of the wild-type IGF-I receptor. In contrast, the hybrid receptor no longer displayed high-affinity binding of insulin. These results directly demonstrate that it is possible to change the specificity of the insulin receptor to that of the IGF-I receptor and, furthermore, that the binding specificity for IGF-I is encoded within the nucleotide sequence from 135 to 938 of the IGF-I receptor cDNA. Since the hybrid receptor only bound insulin with low affinity, the insulin binding region is likely to be located within exons 2 and 3 of the insulin receptor

Intravenous Immunoglobulins Improve Survival in Monoclonal Gammopathy-Associated Systemic Capillary-Leak Syndrome.

Science.gov (United States)

Pineton de Chambrun, Marc; Gousseff, Marie; Mauhin, Wladimir; Lega, Jean-Christophe; Lambert, Marc; Rivière, Sophie; Dossier, Antoine; Ruivard, Marc; Lhote, François; Blaison, Gilles; Alric, Laurent; Agard, Christian; Saadoun, David; Graveleau, Julie; Soubrier, Martin; Lucchini-Lecomte, Marie-Josée; Christides, Christine; Bosseray, Annick; Levesque, Hervé; Viallard, Jean-François; Tieulie, Nathalie; Lovey, Pierre-Yves; Le Moal, Sylvie; Bibes, Béatrice; Malizia, Giuseppe; Abgueguen, Pierre; Lifermann, François; Ninet, Jacques; Hatron, Pierre-Yves; Amoura, Zahir

2017-10-01

Monoclonal gammopathy-associated systemic capillary-leak syndrome, also known as Clarkson disease, is a rare condition characterized by recurrent life-threatening episodes of capillary hyperpermeability in the context of a monoclonal gammopathy. This study was conducted to better describe the clinical characteristics, natural history, and long-term outcome of monoclonal gammopathy-associated systemic capillary-leak syndrome. We conducted a cohort analysis of all patients included in the European Clarkson disease (EurêClark) registry between January 1997 and March 2016. From diagnosis to last follow-up, studied outcomes (eg, the frequency and severity of attacks, death, and evolution toward multiple myeloma) and the type of preventive treatments administered were monitored every 6 months. Sixty-nine patients (M/F sex ratio 1:1; mean ± SD age at disease onset 52 ± 12 years) were included in the study. All patients had monoclonal gammopathy of immunoglobulin G type, with kappa light chains in 47 (68%). Median (interquartile range) follow-up duration was 5.1 (2.5-9.7) years. Twenty-four patients (35%) died after 3.3 (0.9-8) years. Fifty-seven (86%) patients received at least one preventive treatment, including intravenous immunoglobulins (IVIg) n = 48 (73.8%), theophylline n = 22 (33.8%), terbutaline n = 22 (33.8%), and thalidomide n = 5 (7.7%). In the 65 patients with follow-up, 5- and 10-year survival rates were 78% (n = 35) and 69% (n = 17), respectively. Multivariate analysis found preventive treatment with IVIg (hazard ratio 0.27; 95% confidence interval, 0.10-0.70; P = .007) and terbutaline (hazard ratio 0.35; 95% confidence interval, 0.13-0.96; P = .041) to be independent predictors of mortality. We describe the largest cohort to date of patients with well-defined monoclonal gammopathy-associated systemic capillary-leak syndrome. Preventive treatment with IVIg was the strongest factor associated with survival, suggesting the use of IVIg as the first

Up-regulation of proproliferative genes and the ligand/receptor pair placental growth factor and vascular endothelial growth factor receptor 1 in hepatitis C cirrhosis.

Science.gov (United States)

Huang, Xiao X; McCaughan, Geoffrey W; Shackel, Nicholas A; Gorrell, Mark D

2007-09-01

Cirrhosis can lead to hepatocellular carcinoma (HCC). Non-diseased liver and hepatitis C virus (HCV)-associated cirrhosis with or without HCC were compared. Proliferation pathway genes, immune response genes and oncogenes were analysed by a quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and immunostaining. Real-time RT-PCR showed up-regulation of genes in HCV cirrhosis including the proliferation-associated genes bone morphogenetic protein 3 (BMP3), placental growth factor 3 (PGF3), vascular endothelial growth factor receptor 1 (VEGFR1) and soluble VEGFR1, the oncogene FYN, and the immune response-associated genes toll-like receptor 9 (TLR9) and natural killer cell transcript 4 (NK4). Expressions of TLR2 and the oncogenes B-cell CLL/lymphoma 9 (BCL9) and PIM2 were decreased in HCV cirrhosis. In addition, PIM2 and TLR2 were increased in HCV cirrhosis with HCC compared with HCV cirrhosis. The ligand/receptor pair PGF and VEGFR1 was intensely expressed by the portal tract vascular endothelium. VEGFR1 was expressed in reactive biliary epithelial structures in fibrotic septum and in some stellate cells and macrophages. PGF and VEGFR1 may have an important role in the pathogenesis of the neovascular response in cirrhosis.

A Monoclonal Antibody against Wnt-1 Induces Apoptosis in Human Cancer Cells

Directory of Open Access Journals (Sweden)

Biao He

2004-01-01

Full Text Available Aberrant activation of the Wingless-type (Wnt/β-catenin signaling pathway is associated with a variety of human cancers. Little is known regarding the role that Wnt ligands play in human carcinogenesis. To test whether a Wnt-1 signal is a survival factor in human cancer cells and thus may serve as a potential cancer therapeutic target, we investigated the effect of inhibition of Wnt-1 signaling in a variety of human cancer cell lines, including non small cell lung cancer, breast cancer, mesothelioma, and sarcoma. Both monoclonal antibody and RNA interference (RNAi were used to inhibit Wnt-1 signaling. We found that incubation of a monoclonal anti-Wnt-1 antibody induced apoptosis and caused downstream protein changes in cancer cells overexpressing Wnt-1. In contrast, apoptosis was not detected in cells lacking or having minimal Wnt-1 expression after the antibody incubation. RNAi targeting of Wnt-1 in cancer cells overexpressing Wnt-1 demonstrated similar downstream protein changes and induction of apoptosis. The antibody also suppressed tumor growth in vivo. Our results indicate that both monoclonal anti-Wnt-1 antibody and Wnt-1 siRNA inhibit Wnt-1 signaling and can induce apoptosis in human cancer cells. These findings hold promise as a novel therapeutic strategy for cancer.

Preclinical evaluation of radiolabelled nimotuzumab, a promising monoclonal antibody targeting the epidermal growth factor receptor

Czech Academy of Sciences Publication Activity Database

Bárta, P.; Lázníčková, A.; Lázníček, M.; Beckford, Denis R.; Beran, Miloš

2013-01-01

Roč. 56, č. 5 (2013), s. 280-288 ISSN 0362-4803 Grant - others:GA ČR(CZ) GAP304/10/1738 Institutional support: RVO:61389005 Keywords : radiopharmaceutical * 177Lu * 131I * nimotuzumab * EGFR * preclinical biodistribution Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 1.187, year: 2013

A new monoclonal antibody detects downregulation of protein tyrosine phosphatase receptor type γ in chronic myeloid leukemia patients

Directory of Open Access Journals (Sweden)

Marzia Vezzalini

2017-06-01

Full Text Available Abstract Background Protein tyrosine phosphatase receptor gamma (PTPRG is a ubiquitously expressed member of the protein tyrosine phosphatase family known to act as a tumor suppressor gene in many different neoplasms with mechanisms of inactivation including mutations and methylation of CpG islands in the promoter region. Although a critical role in human hematopoiesis and an oncosuppressor role in chronic myeloid leukemia (CML have been reported, only one polyclonal antibody (named chPTPRG has been described as capable of recognizing the native antigen of this phosphatase by flow cytometry. Protein biomarkers of CML have not yet found applications in the clinic, and in this study, we have analyzed a group of newly diagnosed CML patients before and after treatment. The aim of this work was to characterize and exploit a newly developed murine monoclonal antibody specific for the PTPRG extracellular domain (named TPγ B9-2 to better define PTPRG protein downregulation in CML patients. Methods TPγ B9-2 specifically recognizes PTPRG (both human and murine by flow cytometry, western blotting, immunoprecipitation, and immunohistochemistry. Results Co-localization experiments performed with both anti-PTPRG antibodies identified the presence of isoforms and confirmed protein downregulation at diagnosis in the Philadelphia-positive myeloid lineage (including CD34+/CD38bright/dim cells. After effective tyrosine kinase inhibitor (TKI treatment, its expression recovered in tandem with the return of Philadelphia-negative hematopoiesis. Of note, PTPRG mRNA levels remain unchanged in tyrosine kinase inhibitors (TKI non-responder patients, confirming that downregulation selectively occurs in primary CML cells. Conclusions The availability of this unique antibody permits its evaluation for clinical application including the support for diagnosis and follow-up of these disorders. Evaluation of PTPRG as a potential therapeutic target is also facilitated by the

Bone marrow dosimetry for monoclonal antibody therapy

International Nuclear Information System (INIS)

Bigler, R.E.; Zanzonico, P.B.; Leonard, R.

1986-01-01

Immunoglobulins must permeate through the basement membrane of capillaries in order to enter the extracellular space (ECS) of tissue. Since the process is quite slow, the blood plasma activity in various organs contributes considerably to the radiation dose of the dose-limiting tissues. In bone marrow the basement membrane is absent and the blood circulation is functionally open. Therefore, blood plasma and marrow ECS maintain equal concentrations of labeled immunoglobulins. A combination of factors including intravenous administration, slow absorption into most tissues, slow breakdown and elimination of labeled immunoglobulin, and rapid entry into bone marrow ECS as well as known radiosensitivity of marrow led the authors to expect this tissue would prove to be the primary tissue at risk for systemic monoclonal antibody therapy. They have developed and applied in a Phase I clinical study of 131 I labeled CEA antibody a procedure for estimation of radiation dose to red bone marrow. Serieal measurements of blood plasma and total body retention are carried out. Binding of labeled antibody to the cellular components of blood is verified to be very low. They have observed bone marrow depression at doses greater than 400 rad. If no special procedures are used to reconstitute marrow after radiation treatment, this level represents a much greater than generally recognized limitation to radiolabeled monoclonal antibody therapy. 25 references, 4 tables

Selective binding and oligomerization of the murine granulocyte colony-stimulating factor receptor by a low molecular weight, nonpeptidyl ligand.

Science.gov (United States)

Doyle, Michael L; Tian, Shin-Shay; Miller, Stephen G; Kessler, Linda; Baker, Audrey E; Brigham-Burke, Michael R; Dillon, Susan B; Duffy, Kevin J; Keenan, Richard M; Lehr, Ruth; Rosen, Jon; Schneeweis, Lumelle A; Trill, John; Young, Peter R; Luengo, Juan I; Lamb, Peter

2003-03-14

Granulocyte colony-stimulating factor regulates neutrophil production by binding to a specific receptor, the granulocyte colony-stimulating factor receptor, expressed on cells of the granulocytic lineage. Recombinant forms of granulocyte colony-stimulating factor are used clinically to treat neutropenias. As part of an effort to develop granulocyte colony-stimulating factor mimics with the potential for oral bioavailability, we previously identified a nonpeptidyl small molecule (SB-247464) that selectively activates murine granulocyte colony-stimulating factor signal transduction pathways and promotes neutrophil formation in vivo. To elucidate the mechanism of action of SB-247464, a series of cell-based and biochemical assays were performed. The activity of SB-247464 is strictly dependent on the presence of zinc ions. Titration microcalorimetry experiments using a soluble murine granulocyte colony-stimulating factor receptor construct show that SB-247464 binds to the extracellular domain of the receptor in a zinc ion-dependent manner. Analytical ultracentrifugation studies demonstrate that SB-247464 induces self-association of the N-terminal three-domain fragment in a manner that is consistent with dimerization. SB-247464 induces internalization of granulocyte colony-stimulating factor receptor on intact cells, consistent with a mechanism involving receptor oligomerization. These data show that small nonpeptidyl compounds are capable of selectively binding and inducing productive oligomerization of cytokine receptors.

Efficacy of Wnt-1 monoclonal antibody in sarcoma cells

International Nuclear Information System (INIS)

Mikami, Iwao; Koizumi, Kiyoshi; Jablons, David M; You, Liang; He, Biao; Xu, Zhidong; Batra, Sonny; Lee, Amie Y; Mazieres, Julien; Reguart, Noemi; Uematsu, Kazutsugu

2005-01-01

Sarcomas are one of the most refractory diseases among malignant tumors. More effective therapies based on an increased understanding of the molecular biology of sarcomas are needed as current forms of therapy remain inadequate. Recently, it has been reported that Wnt-1/β-catenin signaling inhibits apoptosis in several cancers. In this study, we investigated the efficacy of a monoclonal anti-Wnt-1 antibody in sarcoma cells. We treated cell lines A-204, SJSA-1, and fresh primary cultures of lung metastasis of sarcoma with a monoclonal anti-Wnt-1 antibody. Wnt-1 siRNA treatment was carried out in A-204. We assessed cell death using Crystal Violet staining. Apoptosis induction was estimated by flow cytometry analysis (Annexin V and PI staining). Cell signaling changes were determined by western blotting analysis. We detected Wnt-1 expression in all tissue samples and cell lines. Significant apoptosis induction was found in monoclonal anti-Wnt-1 antibody treated cells compared to control monoclonal antibody treated cells (p < 0.02). Similarly, we observed increased apoptosis in Wnt-1 siRNA treated cells. Blockade of Wnt-1 signaling in both experiments was confirmed by analyzing intracellular levels of Dishevelled-3 and of cytosolic β-catenin. Furthermore, the monoclonal anti-Wnt-1 antibody also induced cell death in fresh primary cultures of metastatic sarcoma in which Wnt-1 signaling was active. Our results indicate that Wnt-1 blockade by either monoclonal antibody or siRNA induces cell death in sarcoma cells. These data suggest that Wnt-1 may be a novel therapeutic target for the treatment of a subset of sarcoma cells in which Wnt-1/β-catenin signaling is active

Tumor necrosis factor receptor-associated factor 6 (TRAF6) participates in anti-lipopolysaccharide factors (ALFs) gene expression in mud crab.

Science.gov (United States)

Sun, Wan-Wei; Zhang, Xin-Xu; Wan, Wei-Song; Wang, Shu-Qi; Wen, Xiao-Bo; Zheng, Huai-Ping; Zhang, Yue-Ling; Li, Sheng-Kang

2017-02-01

Tumor necrosis factor receptor-associated factor 6 (TRAF6) is a key cytoplasm signal adaptor that mediates signals activated by tumor necrosis factor receptor (TNFR) superfamily and the Interleukin-1 receptor/Toll-like receptor (IL-1/TLR) superfamily. The full-length 2492 bp TRAF6 (Sp-TRAF6) from Scylla paramamosain contains 1800 bp of open reading frame (ORF) encoding 598 amino acids, including an N-terminal RING-type zinc finger, two TRAF-type zinc fingers and a conserved C-terminal meprin and TRAF homology (MATH) domain. Multiple alignment analysis shows that the putative amino acid sequence of Sp-TRAf6 has highest identity of 88% with Pt-TRAF6 from Portunus trituberculatus, while the similarity of Sp-TRAF6 with other crustacean sequences was 54-55%. RT-PCR analysis indicated that Sp-TRAF6 transcripts were predominantly expressed in the hepatopancreas and stomach, whereas it was barely detected in the heart and hemocytes in our study. Moreover, Sp-TRAF6 transcripts were significantly up-regulated after Vibrio parahemolyticus and LPS challenges. RNA interference assay was carried out used by siRNA to investigate the genes expression patterns regulated by Sp-TRAF6. The qRT-PCR results showed that silencing Sp-TRAF6 gene could inhibit SpALF1, SpALF2, SpALF5 and SpALF6 expression in hemocytes, while inhibit SpALF1, SpALF3, SpALF4, SpALF5 and SpALF6 expression in hepatopancreas. Taken together, the acute-phase response to immune challenges and the inhibition of SpALFs gene expression indicate that Sp-TRAF6 plays an important role in host defense against pathogen invasions via regulation of ALF gene expression in S. paramamosain. Copyright © 2016. Published by Elsevier Ltd.

Monoclonal antibodies and Fc fragments for treating solid tumors

Directory of Open Access Journals (Sweden)

Eisenbeis AM

2012-01-01

Full Text Available Andrea M Eisenbeis, Stefan J GrauDepartment of Neurosurgery, University Hospital of Cologne, Cologne, GermanyAbstract: Advances in biotechnology, better understanding of pathophysiological processes, as well as the identification of an increasing number of molecular markers have facilitated the use of monoclonal antibodies and Fc fragments in various fields in medicine. In this context, a rapidly growing number of these substances have also emerged in the field of oncology. This review will summarize the currently approved monoclonal antibodies used for the treatment of solid tumors with a focus on their clinical application, biological background, and currently ongoing trials.Keywords: targeted therapy, monoclonal antibodies, cancer, biological therapy

Tyrosine 769 of the keratinocyte growth factor receptor is required for receptor signaling but not endocytosis

International Nuclear Information System (INIS)

Ceridono, Mara; Belleudi, Francesca; Ceccarelli, Simona; Torrisi, Maria Rosaria

2005-01-01

Keratinocyte growth factor receptor (KGFR) is a receptor tyrosine kinase expressed on epithelial cells which belongs to the family of fibroblast growth factor receptors (FGFRs). Following ligand binding, KGFR is rapidly autophosphorylated on specific tyrosine residues in the intracellular domain, recruits substrate proteins, and is rapidly internalized by clathrin-mediated endocytosis. The role of different autophosphorylation sites in FGFRs, and in particular the role of the tyrosine 766 in FGFR1, first identified as PLCγ binding site, has been extensively studied. We analyzed here the possible role of the tyrosine 769 in KGFR, corresponding to tyrosine 766 in FGFR1, in the regulation of KGFR signal transduction and MAPK activation as well as in the control of the endocytic process of KGFR. A mutant KGFR in which tyrosine 769 was substituted by phenylalanine was generated and transfected in NIH3T3 and HeLa cells. Our results indicate that tyrosine 769 is required for the binding to KGFR and tyrosine phosphorylation of PLCγ as well as for the full activation of MAPKs and for cell proliferation through the regulation of FRS2 tyrosine phosphorylation, suggesting that this residue represents a key regulator of KGFR signal transduction. Our data also show that tyrosine 769 is not involved in the regulation of the endocytic process of KGFR

Polyclonal and monoclonal antibodies in clinic.

Science.gov (United States)

Wootla, Bharath; Denic, Aleksandar; Rodriguez, Moses

2014-01-01

Immunoglobulins (Ig) or antibodies are heavy plasma proteins, with sugar chains added to amino-acid residues by N-linked glycosylation and occasionally by O-linked glycosylation. The versatility of antibodies is demonstrated by the various functions that they mediate such as neutralization, agglutination, fixation with activation of complement and activation of effector cells. Naturally occurring antibodies protect the organism against harmful pathogens, viruses and infections. In addition, almost any organic chemical induces antibody production of antibodies that would bind specifically to the chemical. These antibodies are often produced from multiple B cell clones and referred to as polyclonal antibodies. In recent years, scientists have exploited the highly evolved machinery of the immune system to produce structurally and functionally complex molecules such as antibodies from a single B clone, heralding the era of monoclonal antibodies. Most of the antibodies currently in the clinic, target components of the immune system, are not curative and seek to alleviate symptoms rather than cure disease. Our group used a novel strategy to identify reparative human monoclonal antibodies distinct from conventional antibodies. In this chapter, we discuss the therapeutic relevance of both polyclonal and monoclonal antibodies in clinic.

Radioimmunoimaging of experimental gliomas using radiolabelled monoclonal antibodies

International Nuclear Information System (INIS)

Glaessner, H.

1986-01-01

The biodistribution and tumour uptake of radiolabelled (131 I) glioma-seeking monoclonal antibodies (14 AC1) and their F(ab') 2 fragments were investigated in nude mice having received glioma transplants. Radioimmunoimaging by external scintigraphy at 48 and 96 hours pointed to a superior tumour localisation by the fragments that was clearly related to the dose. Wholebody determinations of the biokinetic behaviour led to the following results: Faster clearance anc more ready elimination from the blood pool for the fragments, preferential uptake in the tumour; intact antibodies; binding in the liver, spleen and lungs. The study confirmed the value of fragments of monoclonal antibodies in the diagnosis of tumours and pointed to the possibility of using intact monoclonal antibodies as carriers of radioisotopes and cytotoxic drugs within the scope of therapeutic programmes. (TRV) [de

Insulin-like growth factors (IGFs) as autocrine/paracrine regulators of granulosa cell differentiation and growth: Studies with a neutralizing monoclonal antibody to IGF-I

International Nuclear Information System (INIS)

Mondschein, J.S.; Canning, S.F.; Miller, D.Q.; Hammond, J.M.

1989-01-01

Evidence that granulosa cells secrete and respond to insulin-like growth factors (IGFs) suggests, but does not prove, the importance of IGFs as intraovarian regulators. To further assess the role of these peptides in ovarian function, a neutralizing monoclonal antibody to IGF-I was employed to block the actions of IGFs in porcine follicular fluid and in granulosa cell-conditioned medium. In one series of experiments, granulosa cells from immature porcine follicles were cultured in medium containing porcine follicular fluid that had been charcoal-treated to remove steroids. As noted before, fluid from large follicles (LFF) stimulated progesterone production in a dose-dependent manner. The stimulatory effect of LFF (30% v/v) could be inhibited by greater than 50% by the anti-IGF monoclonal antibody. This inhibitory action was specific for the anti-IGF antibody and could be overcome by the addition of excess exogenous IGFs. In another series of experiments, granulosa cells were made dependent on endogenously produced IGFs by culturing them in a serum-free medium without exogenous growth factors. The effects of follicle-stimulating hormone (FSH), estradiol (E2), growth hormone (GH), and combinations thereof on progesterone production were inhibited by approximately 50% by the anti-IGF antibody. The effects of IGFs on indices of cell growth (judged by the criterion of being inhibited by the anti-IGF antibody) were less dramatic. A modest 18% increase in cell number was observed with FSH and E2 treatment in serum-free medium; this effect was virtually abolished by the antibody

Insulin-like growth factors (IGFs) as autocrine/paracrine regulators of granulosa cell differentiation and growth: Studies with a neutralizing monoclonal antibody to IGF-I

Energy Technology Data Exchange (ETDEWEB)

Mondschein, J.S.; Canning, S.F.; Miller, D.Q.; Hammond, J.M. (Pennsylvania State Univ., Hershey (USA))

1989-07-01

Evidence that granulosa cells secrete and respond to insulin-like growth factors (IGFs) suggests, but does not prove, the importance of IGFs as intraovarian regulators. To further assess the role of these peptides in ovarian function, a neutralizing monoclonal antibody to IGF-I was employed to block the actions of IGFs in porcine follicular fluid and in granulosa cell-conditioned medium. In one series of experiments, granulosa cells from immature porcine follicles were cultured in medium containing porcine follicular fluid that had been charcoal-treated to remove steroids. As noted before, fluid from large follicles (LFF) stimulated progesterone production in a dose-dependent manner. The stimulatory effect of LFF (30% v/v) could be inhibited by greater than 50% by the anti-IGF monoclonal antibody. This inhibitory action was specific for the anti-IGF antibody and could be overcome by the addition of excess exogenous IGFs. In another series of experiments, granulosa cells were made dependent on endogenously produced IGFs by culturing them in a serum-free medium without exogenous growth factors. The effects of follicle-stimulating hormone (FSH), estradiol (E2), growth hormone (GH), and combinations thereof on progesterone production were inhibited by approximately 50% by the anti-IGF antibody. The effects of IGFs on indices of cell growth (judged by the criterion of being inhibited by the anti-IGF antibody) were less dramatic. A modest 18% increase in cell number was observed with FSH and E2 treatment in serum-free medium; this effect was virtually abolished by the antibody.

Tumor detection using radiolabeled monoclonal antibodies

International Nuclear Information System (INIS)

Moldofsky, P.J.; Powe, J.; Hammond, N.D.

1987-01-01

Radioisotope conjugated to monoclonal antibody products has been used for imaging tumors targeted by the antibody. As imaging progresses, new sets of procedural and technical questions arise. In this chapter, we discuss several current problems in imaging tumor with radiolabeled monoclonal antibody. These include (1) methods for selection of specific antibody and, once the particular antibody is selected, which fragment form is to be used; (2) imaging procedures: what are the optimum imaging parameters, such as optimum time for imaging after administration of tracer and considerations regarding background subtraction; and (3) noninvasive quantitative techniques: quantitation of localization of antibody indirectly from quantitative information in the images.100 references

Neurotrophin receptors expression and JNK pathway activation in human astrocytomas

Directory of Open Access Journals (Sweden)

Maraziotis Theodore

2007-10-01

Full Text Available Abstract Background Neurotrophins are growth factors that regulate cell growth, differentiation and apoptosis in the nervous system. Their diverse actions are mediated through two different transmembrane – receptor signaling systems: Trk receptor tyrosine kinases (TrkA, TrkB, TrkC and p75NTR neurotrophin receptor. Trk receptors promote cell survival and differentiation while p75NTR induces, in most cases, the activity of JNK-p53-Bax apoptosis pathway or suppresses intracellular survival signaling cascades. Robust Trk activation blocks p75NTR -induced apoptosis by suppressing the JNK-p53-Bax pathway. The aim of this exploratory study was to investigate the expression levels of neurotrophin receptors, Trks and p75NTR, and the activation of JNK pathway in human astrocytomas and in adjacent non-neoplastic brain tissue. Methods Formalin-fixed paraffin-embedded serial sections from 33 supratentorial astrocytomas (5 diffuse fibrillary astrocytomas, WHO grade II; 6 anaplastic astrocytomas, WHO grade III; 22 glioblastomas multiforme, WHO grade IV were immunostained following microwave pretreatment. Polyclonal antibodies against TrkA, TrkB, TrkC and monoclonal antibodies against p75NTR and phosphorylated forms of JNK (pJNK and c-Jun (pc-Jun were used. The labeling index (LI, defined as the percentage of positive (labeled cells out of the total number of tumor cells counted, was determined. Results Moderate to strong, granular cytoplasmic immunoreactivity for TrkA, TrkB and TrkC receptors was detected in greater than or equal to 10% of tumor cells in the majority of tumors independently of grade; on the contrary, p75NTR receptor expression was found in a small percentage of tumor cells (~1% in some tumors. The endothelium of tumor capillaries showed conspicuous immunoreactivity for TrkB receptor. Trk immunoreactivity seemed to be localized in some neurons and astrocytes in non-neoplastic tissue. Phosphorylated forms of JNK (pJNK and c-Jun (pc-Jun were

An automated robotic platform for rapid profiling oligosaccharide analysis of monoclonal antibodies directly from cell culture.

Science.gov (United States)

Doherty, Margaret; Bones, Jonathan; McLoughlin, Niaobh; Telford, Jayne E; Harmon, Bryan; DeFelippis, Michael R; Rudd, Pauline M

2013-11-01

Oligosaccharides attached to Asn297 in each of the CH2 domains of monoclonal antibodies play an important role in antibody effector functions by modulating the affinity of interaction with Fc receptors displayed on cells of the innate immune system. Rapid, detailed, and quantitative N-glycan analysis is required at all stages of bioprocess development to ensure the safety and efficacy of the therapeutic. The high sample numbers generated during quality by design (QbD) and process analytical technology (PAT) create a demand for high-performance, high-throughput analytical technologies for comprehensive oligosaccharide analysis. We have developed an automated 96-well plate-based sample preparation platform for high-throughput N-glycan analysis using a liquid handling robotic system. Complete process automation includes monoclonal antibody (mAb) purification directly from bioreactor media, glycan release, fluorescent labeling, purification, and subsequent ultra-performance liquid chromatography (UPLC) analysis. The entire sample preparation and commencement of analysis is achieved within a 5-h timeframe. The automated sample preparation platform can easily be interfaced with other downstream analytical technologies, including mass spectrometry (MS) and capillary electrophoresis (CE), for rapid characterization of oligosaccharides present on therapeutic antibodies. Copyright © 2013 Elsevier Inc. All rights reserved.

Flow cytometric detection of growth factor receptors in autografts and analysis of growth factor concentrations in autologous stem cell transplantation: possible significance for platelet recovery

DEFF Research Database (Denmark)

Schiødt, I; Jensen, Charlotte Harken; Kjaersgaard, E

2000-01-01

In order to improve prediction of hematopoietic recovery, we conducted a pilot study, analyzing the significance of growth factor receptor expression in autografts as well as endogenous growth factor levels in blood before, during and after stem cell transplantation. Three early acting (stem cell......-CSF receptor positive, CD34+ progenitor cells were measured by flow cytometry in the leukapheresis product used for transplantation in a subgroup of 15 patients (NHL, n = 8, MM, n = 7). Three factors were identified as having a significant impact on platelet recovery. First, the level of Tpo in blood...... at the time of the nadir (day +7). Second, the percentage of re-infused thrombopoietin receptor positive progenitors and finally, the percentage of Flt3 receptor positive progenitors. On the other hand, none of the analyzed factors significantly predicted myeloid or erythroid recovery. These findings need...

A receptor model for urban aerosols based on oblique factor analysis

DEFF Research Database (Denmark)

Keiding, Kristian; Sørensen, Morten S.; Pind, Niels

1987-01-01

A procedure is outlined for the construction of receptor models of urban aerosols, based on factor analysis. The advantage of the procedure is that the covariation of source impacts is included in the construction of the models. The results are compared with results obtained by other receptor......-modelling procedures. It was found that procedures based on correlating sources were physically sound as well as in mutual agreement. Procedures based on non-correlating sources were found to generate physically obscure models....

Dissecting Immunogenicity of Monoclonal Antibodies

National Research Council Canada - National Science Library

Snyder, Christopher

2003-01-01

The potential of monoclonal antibodies, (mAbs), for use in therapeutic and diagnostic applications has not been fully realized in part due to counter-immune responses that often arise in patient recipients of mAb...

Cell-cell adhesion mediated by binding of membrane-anchored transforming growth factor α to epidermal growth factor receptors promotes cell proliferation

International Nuclear Information System (INIS)

Anklesaria, P.; Greenberger, J.S.; Teixido, J.; Laiho, M.; Massague, J.; Pierce, J.H.

1990-01-01

The precursor for transforming growth factor α, pro-TGF-α, is a cell surface glycoprotein that can establish contact with epidermal growth factor (EGF) receptors on adjacent cells. To examine whether the pro-TGF-α/EGF receptor pair can simultaneously mediate cell adhesion and promote cell proliferation, the authors have expressed pro-TGF-α in a bone marrow stromal cell line labeled with [ 35 S] cysteine. Expression of pro-TGF-α allows these cells to support long-term attachment of an EGF/interleukin-3-dependent hematopoietic progenitor cell line that expresses EGF receptors but is unable to adhere to normal stroma. This interaction is inhibited by soluble EGF receptor ligands. Further, the hematopoietic progenitor cells replicate their DNA while they are attached to the stromal cell layer and become foci of sustained cell proliferation. Thus, pro-TGF-α and the EGF receptor can function as mediators of intercellular adhesion and this interaction may promote a mitogenic response. They propose the term juxtacrine to designate this form of stimulation between adjacent cells

Structural model for the interaction of a designed Ankyrin Repeat Protein with the human epidermal growth factor receptor 2.

Directory of Open Access Journals (Sweden)

V Chandana Epa

Full Text Available Designed Ankyrin Repeat Proteins are a class of novel binding proteins that can be selected and evolved to bind to targets with high affinity and specificity. We are interested in the DARPin H10-2-G3, which has been evolved to bind with very high affinity to the human epidermal growth factor receptor 2 (HER2. HER2 is found to be over-expressed in 30% of breast cancers, and is the target for the FDA-approved therapeutic monoclonal antibodies trastuzumab and pertuzumab and small molecule tyrosine kinase inhibitors. Here, we use computational macromolecular docking, coupled with several interface metrics such as shape complementarity, interaction energy, and electrostatic complementarity, to model the structure of the complex between the DARPin H10-2-G3 and HER2. We analyzed the interface between the two proteins and then validated the structural model by showing that selected HER2 point mutations at the putative interface with H10-2-G3 reduce the affinity of binding up to 100-fold without affecting the binding of trastuzumab. Comparisons made with a subsequently solved X-ray crystal structure of the complex yielded a backbone atom root mean square deviation of 0.84-1.14 Ångstroms. The study presented here demonstrates the capability of the computational techniques of structural bioinformatics in generating useful structural models of protein-protein interactions.

Negative hyper-selection of metastatic colorectal cancer patients for anti-EGFR monoclonal antibodies: the PRESSING case-control study.

Science.gov (United States)

Cremolini, C; Morano, F; Moretto, R; Berenato, R; Tamborini, E; Perrone, F; Rossini, D; Gloghini, A; Busico, A; Zucchelli, G; Baratelli, C; Tamburini, E; Tampellini, M; Sensi, E; Fucà, G; Volpi, C; Milione, M; Di Maio, M; Fontanini, G; De Braud, F; Falcone, A; Pietrantonio, F

2017-12-01

Refining the selection of metastatic colorectal cancer patients candidates for anti-epidermal growth factor receptor (EGFR) monoclonal antibodies beyond RAS and BRAF testing is a challenge of precision oncology. Several uncommon genomic mechanisms of primary resistance, leading to activation of tyrosine kinase receptors other than EGFR or downstream signalling pathways, have been suggested by preclinical and retrospective studies. We conducted this multicentre, prospective, case-control study to demonstrate the negative predictive impact of a panel of rare genomic alterations [PRESSING (PRimary rESiStance IN RAS and BRAF wild-type metastatic colorectal cancer patients treated with anti-eGfr monoclonal antibodies) panel], including HER2/MET amplifications, ALK/ROS1/NTRK1-3/RET fusions and PIK3CA mutations. Hypothesizing a prevalence of candidate alterations of 15% and 0% in resistant and sensitive RAS and BRAF wild-type patients, respectively, with two-sided α and β errors of 0.05 and 0.20, 47 patients per group were needed. Forty-seven patients per group were included. PRESSING panel alterations were significantly more frequent in resistant (24 out of 47, 51.1%) than in sensitive (1 out of 47, 2.1%) patients (P < 0.001) and in right- (12 out of 29, 41.4%) than left-sided (13 out of 65, 20.0%) tumours (P = 0.03). The predictive accuracy of PRESSING panel and sidedness was 75.3% and 70.2%, respectively. Among hyper-selected patients, right-sidedness was still associated with resistance (P = 0.002). The predictive accuracy of the combined evaluation of PRESSING panel and sidedness was 80.4%. As a secondary analysis, 8 (17.0%) resistant and 0 sensitive patients showed microsatellite instability (P < 0.001). The investigated panel of genomic alterations allows refining the selection of RAS and BRAF wild-type metastatic colorectal cancer patients candidates for anti-EGFRs, partially explaining and further corroborating the predictive ability of primary

Inhibition of Epidermal Growth Factor Receptor and Vascular Endothelial Growth Factor Receptor Phosphorylation on Tumor-Associated Endothelial Cells Leads to Treatment of Orthotopic Human Colon Cancer in Nude Mice

Directory of Open Access Journals (Sweden)

Takamitsu Sasaki

2007-12-01

Full Text Available The purpose of our study was to determine whether the dual inhibition of epidermal growth factor receptor (EGFR and vascular endothelial growth factor receptor (VEGFR signaling pathways in tumor-associated endothelial cells can inhibit the progressive growth of human colon carcinoma in the cecum of nude mice. SW620CE2 human colon cancer cells growing in culture and orthotopically in the cecum of nude mice expressed a high level of transforming growth factor alpha (TGF-α and vascular endothelial growth factor (VEGF but were negative for EGFR, human epidermal growth factor receptor 2 (HER2, VEGFR. Double immunofluorescence staining revealed that tumorassociated endothelial cells expressed EGFR, VEGFR2, phosphorylated EGFR (pEGFR, phosphorylated VEGFR (pVEGFR. Treatment of mice with either 7H-pyrrolo [2,3-d]-pyrimidine lead scaffold (AEE788; an inhibitor of EGFR and VEGFR tyrosine kinase or CPT-11 as single agents significantly inhibited the growth of cecal tumors (P < .01; this decrease was even more pronounced with AEE788 combined with CPT-11 (P < .001. AEE788 alone or combined with CPT-11 also inhibited the expression of pEGFR and pVEGFR on tumor-associated endothelial cells, significantly decreased vascularization and tumor cell proliferation, increased the level of apoptosis in both tumorassociated endothelial cells and tumor cells. These data demonstrate that targeting EGFR and VEGFR signaling on tumor-associated endothelial cells provides a viable approach for the treatment of colon cancer.

Molecular mechanism for the action of the anti-CD44 monoclonal antibody MEM-85

Czech Academy of Sciences Publication Activity Database

Škerlová, Jana; Král, V.; Kachala, M.; Fábry, M.; Bumba, L.; Svergun, D. I.; Tošner, Z.; Veverka, Václav; Řezáčová, Pavlína

2015-01-01

Roč. 191, č. 2 (2015), s. 214-223 ISSN 1047-8477 R&D Projects: GA MŠk(CZ) LK11205; GA MŠk(CZ) LO1304 Institutional support: RVO:61388963 Keywords : CD44 * epitope mapping * monoclonal antibody * MEM-85 * NMR * SAXS Subject RIV: CE - Biochemistry Impact factor: 2.570, year: 2015

Factors associated with an increased risk of vertebral fracture in monoclonal gammopathies of undetermined significance

International Nuclear Information System (INIS)

Piot, J M; Royer, M; Schmidt-Tanguy, A; Hoppé, E; Gardembas, M; Bourrée, T; Hunault, M; François, S; Boyer, F; Ifrah, N; Renier, G; Chevailler, A; Audran, M; Chappard, D; Libouban, H; Mabilleau, G; Legrand, E; Bouvard, B

2015-01-01

Monoclonal gammopathies of undetermined significance (MGUS) have been shown to be associated with an increased risk of fractures. This study describes prospectively the bone status of MGUS patients and determines the factors associated with vertebral fracture. We included prospectively 201 patients with MGUS, incidentally discovered, and with no known history of osteoporosis: mean age 66.6±12.5 years, 48.3% women, 51.7% immunoglobulin G (IgG), 33.3% IgM and 10.4% IgA. Light chain was kappa in 64.2% patients. All patients had spinal radiographs and bone mineral density measurement in addition to gammopathy assessment. At least one prevalent non-traumatic vertebral fracture was discovered in 18.4% patients and equally distributed between men and women. Fractured patients were older, had a lower bone density and had also more frequently a lambda light chain isotype. Compared with patients with κ light chain, the odds ratio of being fractured for patients with λ light chain was 4.32 (95% confidence interval 1.80–11.16; P=0.002). These results suggest a high prevalence of non-traumatic vertebral fractures in MGUS associated with lambda light chain isotype and not only explained by low bone density

Epidermal growth factor receptor in primary human lung cancer

International Nuclear Information System (INIS)

Yu Xueyan; Hu Guoqiang; Tian Keli; Wang Mingyun

1996-01-01

Cell membranes were prepared from 12 human lung cancers for the study of the expression of epidermal growth factor receptors (EGFR). EGFR concentration was estimated by ligand binding studies using 125 I-radiolabeled EGF. The dissociation constants of the high affinity sites were identical, 1.48 nmol and 1.1 nmol in cancer and normal lung tissues, the EGFR contents were higher in lung cancer tissues (range: 2.25 to 19.39 pmol·g -1 membrane protein) than that in normal tissues from the same patients (range: 0.72 to 7.43 pmol·g -1 membrane protein). These results suggest that EGF and its receptor may play a role in the regulatory mechanisms in the control of lung cellular growth and tumor promotion

Thyroid hormone and retinoic acid nuclear receptors: specific ligand-activated transcription factors

International Nuclear Information System (INIS)

Brtko, J.

1998-01-01

Transcriptional regulation by both the thyroid hormone and the vitamin A-derived 'retinoid hormones' is a critical component in controlling many aspects of higher vertebrate development and metabolism. Their functions are mediated by nuclear receptors, which comprise a large super-family of ligand-inducible transcription factors. Both the thyroid hormone and the retinoids are involved in a complex arrangement of physiological and development responses in many tissues of higher vertebrates. The functions of 3,5,3'-triiodothyronine (T 3 ), the thyromimetically active metabolite of thyroxine as well as all-trans retinoic acid, the biologically active vitamin A metabolite are mediated by nuclear receptor proteins that are members of the steroid/thyroid/retinoid hormone receptor family. The functions of all members of the receptor super family are discussed. (authors)

Potent neutralization of hepatitis A virus reveals a receptor mimic mechanism and the receptor recognition site.

Science.gov (United States)

Wang, Xiangxi; Zhu, Ling; Dang, Minghao; Hu, Zhongyu; Gao, Qiang; Yuan, Shuai; Sun, Yao; Zhang, Bo; Ren, Jingshan; Kotecha, Abhay; Walter, Thomas S; Wang, Junzhi; Fry, Elizabeth E; Stuart, David I; Rao, Zihe

2017-01-24

Hepatitis A virus (HAV) infects ∼1.4 million people annually and, although there is a vaccine, there are no licensed therapeutic drugs. HAV is unusually stable (making disinfection problematic) and little is known of how it enters cells and releases its RNA. Here we report a potent HAV-specific monoclonal antibody, R10, which neutralizes HAV infection by blocking attachment to the host cell. High-resolution cryo-EM structures of HAV full and empty particles and of the complex of HAV with R10 Fab reveal the atomic details of antibody binding and point to a receptor recognition site at the pentamer interface. These results, together with our observation that the R10 Fab destabilizes the capsid, suggest the use of a receptor mimic mechanism to neutralize virus infection, providing new opportunities for therapeutic intervention.

SPECT assay of radiolabeled monoclonal antibodies

International Nuclear Information System (INIS)

Jaszczak, R.J.

1992-02-01

The long-term goal of this research project is to develop methods to improve the utility of single photon emission computed tomography (SPECI) to quantify the biodistribution of monoclonal antibodies (MoAbs) labeled with clinically relevant radionuclides ( 123 I, 131 I, and 111 In) and with another radionuclide, 211 At, recently used in therapy. We describe here our progress in developing quantitative SPECT methodology for 111 In and 123 I. We have focused our recent research thrusts on the following aspects of SPECT: (1) The development of improved SPECT hardware, such as improved acquisition geometries. (2) The development of better reconstruction methods that provide accurate compensation for the physical factors that affect SPECT quantification. (3) The application of carefully designed simulations and experiments to validate our hardware and software approaches

Identifying risk factors for exposure to culturable allergenic moulds in energy efficient homes by using highly specific monoclonal antibodies

Energy Technology Data Exchange (ETDEWEB)

Sharpe, Richard A. [European Centre for Environment and Human Health, University of Exeter Medical School, Truro TR1 3HD (United Kingdom); Cocq, Kate Le [Rothamsted Research, North Wyke, Okehampton EX20 2SB (United Kingdom); Nikolaou, Vasilis [University of Exeter Medical School, The Veysey Building, Salmon Pool Lane, Exeter EX2 4SG (United Kingdom); Osborne, Nicholas J. [European Centre for Environment and Human Health, University of Exeter Medical School, Truro TR1 3HD (United Kingdom); Clinical Pharmacology and Toxicology Research Group, Discipline of Pharmacology, Sydney Medical School, The University of Sydney, NSW (Australia); Thornton, Christopher R., E-mail: c.r.thornton@exeter.ac.uk [Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD (United Kingdom)

2016-01-15

The aim of this study was to determine the accuracy of monoclonal antibodies (mAbs) in identifying culturable allergenic fungi present in visible mould growth in energy efficient homes, and to identify risk factors for exposure to these known allergenic fungi. Swabs were taken from fungal contaminated surfaces and culturable yeasts and moulds isolated by using mycological culture. Soluble antigens from cultures were tested by ELISA using mAbs specific to the culturable allergenic fungi Aspergillus and Penicillium spp., Ulocladium, Alternaria, and Epicoccum spp., Cladosporium spp., Fusarium spp., and Trichoderma spp. Diagnostic accuracies of the ELISA tests were determined by sequencing of the internally transcribed spacer 1 (ITS1)-5.8S-ITS2-encoding regions of recovered fungi following ELISA. There was 100% concordance between the two methods, with ELISAs providing genus-level identity and ITS sequencing providing species-level identities (210 out of 210 tested). Species of Aspergillus/Penicillium, Cladosporium, Ulocladium/Alternaria/Epicoccum, Fusarium and Trichoderma were detected in 82% of the samples. The presence of condensation was associated with an increased risk of surfaces being contaminated by Aspergillus/Penicillium spp. and Cladosporium spp., whereas moisture within the building fabric (water ingress/rising damp) was only associated with increased risk of Aspergillus/Penicillium spp. Property type and energy efficiency levels were found to moderate the risk of indoor surfaces becoming contaminated with Aspergillus/Penicillium and Cladosporium which in turn was modified by the presence of condensation, water ingress and rising damp, consistent with previous literature. - Highlights: • Monoclonal antibodies were used to track culturable allergenic moulds in homes. • Allergenic moulds were recovered from 82% of swabs from contaminated surfaces. • The mAbs were highly specific with 100% agreement to PCR of recovered fungi. • Improvements to energy

Identifying risk factors for exposure to culturable allergenic moulds in energy efficient homes by using highly specific monoclonal antibodies

International Nuclear Information System (INIS)

Sharpe, Richard A.; Cocq, Kate Le; Nikolaou, Vasilis; Osborne, Nicholas J.; Thornton, Christopher R.

2016-01-01

The aim of this study was to determine the accuracy of monoclonal antibodies (mAbs) in identifying culturable allergenic fungi present in visible mould growth in energy efficient homes, and to identify risk factors for exposure to these known allergenic fungi. Swabs were taken from fungal contaminated surfaces and culturable yeasts and moulds isolated by using mycological culture. Soluble antigens from cultures were tested by ELISA using mAbs specific to the culturable allergenic fungi Aspergillus and Penicillium spp., Ulocladium, Alternaria, and Epicoccum spp., Cladosporium spp., Fusarium spp., and Trichoderma spp. Diagnostic accuracies of the ELISA tests were determined by sequencing of the internally transcribed spacer 1 (ITS1)-5.8S-ITS2-encoding regions of recovered fungi following ELISA. There was 100% concordance between the two methods, with ELISAs providing genus-level identity and ITS sequencing providing species-level identities (210 out of 210 tested). Species of Aspergillus/Penicillium, Cladosporium, Ulocladium/Alternaria/Epicoccum, Fusarium and Trichoderma were detected in 82% of the samples. The presence of condensation was associated with an increased risk of surfaces being contaminated by Aspergillus/Penicillium spp. and Cladosporium spp., whereas moisture within the building fabric (water ingress/rising damp) was only associated with increased risk of Aspergillus/Penicillium spp. Property type and energy efficiency levels were found to moderate the risk of indoor surfaces becoming contaminated with Aspergillus/Penicillium and Cladosporium which in turn was modified by the presence of condensation, water ingress and rising damp, consistent with previous literature. - Highlights: • Monoclonal antibodies were used to track culturable allergenic moulds in homes. • Allergenic moulds were recovered from 82% of swabs from contaminated surfaces. • The mAbs were highly specific with 100% agreement to PCR of recovered fungi. • Improvements to energy

Quantitative imaging with radiolabeled monoclonal antibodies

International Nuclear Information System (INIS)

Moldofsky, P.J.; Hammond, N.D.

1988-01-01

The ability to image tumor by using radiolabeled monoclonal antibody products has been widely demonstrated. The questions of safety and efficacy remain open and require further experience, but at least in some clinical situations radioimmunoimaging has provided clinically useful information. Imaging tumor with radiolabeled monoclonal and polyclonal antibodies has been widely reported, and several summaries have recently appeared. For extensive review of recent clinical imaging the reader is referred to these excellent sources. Having demonstrated the possibility of imaging tumor with radiolabeled antibody, the question now apparent is: will the imaging modality provide information new and different from the already available with established techniques in computed tomography, magnetic resonance imaging, and standard nuclear medicine?

Autocrine growth induced by the insulin-related factor in the insulin-independent teratoma cell line 1246-3A

International Nuclear Information System (INIS)

Yamada, Yukio; Serrero, G.

1988-01-01

An insulin-independent teratoma-derived cell line, called 1246-3A, has been isolated from the adipogenic cell line 1246, which stringently requires insulin for proliferation. The 1246-3A cell line, which can proliferate in the absence of exogenous insulin, produces in its conditioned medium a growth factor similar to pancreatic insulin by its biological and immunological properties. This factor, called insulin-related factor (IRF), was purified and iodinated to study its binding to cell surface receptors. 125 I-labeled IRF binding to intact 1246-3A cells is lower than to 1246 cells. Cell surface binding can be restored by culturing the 1246-3A cells in the presence of an anti-porcine insulin monoclonal antibody of by acid prewash of the cells prior to performing the binding. Scatchard analysis of binding indicates that IRF secreted by the 1246-3A cells partially occupies high-affinity binding sites on the producer cells. Moreover, insulin monoclonal antibody inhibits the proliferation of the IRF-producing 1246-3A cells, suggesting that these cells are dependent on the secreted IRF for growth in culture. The authors conclude that the insulin-related factor secreted by the insulin-independent 1246-3A cells stimulates their proliferation in an autocrine fashion

Epitope Mapping of Monoclonal Antibody PMab-38 Against Dog Podoplanin.

Science.gov (United States)

Chang, Yao-Wen; Yamada, Shinji; Kaneko, Mika K; Kato, Yukinari

2017-12-01

Podoplanin (PDPN), a type I transmembrane sialoglycoprotein, is extensively expressed by normal lymphatic endothelial cells, renal podocytes, and pulmonary type I alveolar cells. Nevertheless, increased expression of PDPN in malignant tumors not only associates with poor prognosis but also facilitates hematogenous metastasis through interaction with C-type lectin-like receptor-2 presented on platelets, followed by PDPN-mediated platelet activation. We previously reported a novel PMab-38 antibody, an anti-dog PDPN (dPDPN) monoclonal antibody, which specifically recognizes PDPN in squamous cell carcinomas melanomas and cancer-associated fibroblasts in canine cancer tissues. However, the specific binding with the epitope of PMab-38 remains undefined. In this study, flow cytometry was utilized to investigate the epitope of PMab-38, which was determined using a series of deletion or point mutants of dPDPN. The results revealed that the critical epitope of PMab-38 is Tyr67 and Glu68 of dPDPN.

A monoclonal antibody that specifically recognizes m6A nucleoside

OpenAIRE

Espuny, Ruth; Castro, Ana; Codony, Carles; Eritja Casadellà, Ramón; Bach-Elias, Montse

1998-01-01

A hybridoma against the nucleoside m6A has been obtained from mouse spleen. This hybridoma was named H65 and it secretes monoclonal antibodies anti-m6A. The competition assays showed that the monoclonal antibody was highly specific for m6A nucleoside.

In-vitro inhibition of IFNγ+ iTreg mediated by monoclonal antibodies against cell surface determinants essential for iTreg function

Directory of Open Access Journals (Sweden)

Daniel Volker

2012-08-01

Full Text Available Abstract Background IFNγ-producing CD4+CD25+Foxp3+ PBL represent a subtype of iTreg that are associated with good long-term graft outcome in renal transplant recipients and suppress alloresponses in-vitro. To study the mechanism of immunosuppression, we attempted to block cell surface receptors and thereby inhibited the function of this iTreg subset in-vitro using monoclonal antibodies and recombinant proteins. Methods PBL of healthy control individuals were stimulated polyclonally in-vitro in the presence of monoclonal antibodies or recombinant proteins against/of CD178, CD152, CD279, CD28, CD95, and HLA-DR. Induction of IFNγ+ iTreg and proliferation of effector cells was determined using four-color fluorescence flow cytometry. Blockade of iTreg function was analyzed using polyclonally stimulated co-cultures with separated CD4+CD25+CD127-IFNγ+ PBL. Results High monoclonal antibody concentrations inhibited the induction of CD4+CD25+Foxp3+IFNγ+ PBL (anti-CD152, anti-CD279, anti-CD95: p +CD25+CD127-IFNγ+ PBL (anti-CD178, anti-CD152, anti-CD279, anti-CD95: p +CD25+Foxp3+IFNγ+ PBL (rCD152 and rCD95: p +CD25+CD127-IFNγ+ PBL showed lower cell proliferation than co-cultures with CD4+CD25+CD127-IFNγ- PBL (p +CD25+CD127-IFNγ- PBL-containing co-cultures in the presence of monoclonal antibody (anti-CD28, anti-CD152, anti-CD279: p +CD25+CD127-IFNγ+ PBL (with the exception anti-CD28 monoclonal antibody: p +CD25+CD127-IFNγ- PBL but do not efficiently block suppressive iTreg function in co-cultures with CD4+CD25+CD127-IFNγ+ PBL. Conclusions CD178, CD152, CD279, CD28, CD95, and HLA-DR determinants are important for induction and suppressive function of IFNγ+ iTreg.

The detection of ovarian cancer using 123I monoclonal antibody

International Nuclear Information System (INIS)

Granowska, M.; Britton, K.E.; Shepherd, J.

1984-01-01

The technique of the production of monoclonal antibodies is described. Antibodies show reactivity with epithelial surfaces of cancer of breast, colon and ovary. The iodogen reaction is used for labelling monoclonal antibodies with 123 I. Description of labelling technique and quality control. After intravenous injection of 74 MBq 123 I-labelled monoclonal antibody (0.5 mg) static camera images of the abdomen were recorded at 10 min, 4 and 22 hours in anterior and posterior position. 20 out of 22 patients with ovarian cancer with and without metastases were correctly diagnosed and confirmed at surgery. (author)

Macrophage colony-stimulating factor, CSF-1, and its proto-oncogene-encoded receptor

International Nuclear Information System (INIS)

Sherr, C.J.; Rettenmier, C.W.; Roussel, M.F.

1988-01-01

The macrophage colony-stimulating factor, CSF-1, or M-CSF, is one of a family of hematopoietic growth factors that stimulates the proliferation of monocytes, macrophages, and their committed bone marrow progenitors. Unlike pluripotent hemopoietins such as granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-3 (IL-3 or multi-CSF), which affect the growth of myeloid cells of several different hematopoietic lineages, CSF-1 acts only on cells of the mononuclear phagocyte series to stimulate their growth and enhance their survival. Retroviral transduction of the feline c-fms gene in the Susan McDonough and Hardy Zuckerman-5 (HZ-5) strains of feline sarcoma virus (FeSV) led to genetic alterations that endowed the recombined viral oncogene (v-fms) with the ability to transform cells in culture morphologically and to induce firbrosarcomas and hematopoietic neoplasms in susceptible animals. The v-fms oncogene product differs from the normal CSF-1 receptor in certain of its cardinal biochemical properties, most notably in exhibiting constitutively high basal levels of tyrosine kinase activity in the absence of its ligand. Comparative studies of the c-fms and v-fms genes coupled with analyses of engineered mutants and receptor chimeras have begun to pinpoint pertinent genetic alterations in the normal receptor gene that unmask its latent oncogenic potential. In addition, the availability of biologically active c-fms, v-fms, and CSF-1 cDNAs has allowed these genes to be mobilized and expressed in naive cells, thereby facilitating assays for receptor coupling with downstream components of the mitogenic pathway in diverse cell types

Monoclonal antibodies in myeloma

DEFF Research Database (Denmark)

Sondergeld, P.; van de Donk, N. W. C. J.; Richardson, P. G.

2015-01-01

The development of monoclonal antibodies (mAbs) for the treatment of disease goes back to the vision of Paul Ehrlich in the late 19th century; however, the first successful treatment with a mAb was not until 1982, in a lymphoma patient. In multiple myeloma, mAbs are a very recent and exciting add...

Monoclonal antibodies to human chorionic gonadotropin and their application to two-site sandwich radioimmunoassay

International Nuclear Information System (INIS)

Mizuchi, A.; Iio, M.; Miyachi, Y.

1984-01-01

Monoclonal antibodies were prepared against human chorionic gonadotropin (HCG). One monoclonal antibody recognized a conformational determinant expressed only on native HCG molecule and another monoclonal antibody had the specificity for the epitopes located on the β-subunit of HCG. Monoclonal antibodies reacting with different antigenic determinants on the HCG molecule were used to develop a simplified 2-site sandwich radioimmunoassay in which one monoclonal antibody was immobilized and another labeled with 125 iodine. This assay was highly specific for HCG and there was no cross-reactivity with α,β-subunit of HCG, luteinizing hormone and follicle stimulating hormone. (Auth.)

Embryonic expression of the transforming growth factor beta ligand and receptor genes in chicken.

Science.gov (United States)

Cooley, James R; Yatskievych, Tatiana A; Antin, Parker B

2014-03-01

Transforming growth factor-beta (TGFβ) signaling regulates a myriad of biological processes during embryogenesis, in the adult, and during the manifestation of disease. TGFβ signaling is propagated through one of three TGFβ ligands interacting with Type I and Type II receptors, and Type III co-receptors. Although TGFβ signaling is regulated partly by the combinatorial expression patterns of TGFβ receptors and ligands, a comprehensive gene expression analysis has not been published. Here we report the embryonic mRNA expression patterns in chicken embryos of the canonical TGFβ ligands (TGFB1, TGFB2, and TGFB3) and receptors (TGFBR1, TGFBR2, TGFBR3), plus the Activin A receptor, type 1 (ACVR1) and co receptor Endoglin (ENG) that also transduce TGFβ signaling. TGFB ligands and receptors show dynamic and frequently overlapping expression patterns in numerous embryonic cell layers and structures. Integrating expression information identifies combinations of ligands and receptors that are involved in specific developmental processes including somitogenesis, cardiogenesis and vasculogenesis. Copyright © 2013 Wiley Periodicals, Inc.

Czech Registry of Monoclonal Gammopathies - Technical Solution, Data Collection and Visualisation.

Science.gov (United States)

Brozova, L; Schwarz, D; Snabl, I; Kalina, J; Pavlickova, B; Komenda, M; Jarkovský, J; Němec, P; Horinek, D; Stefanikova, Z; Pour, L; Hájek, R; Maisnar, V

2017-01-01

The Registry of Monoclonal Gammopathies (RMG) was established by the Czech Myeloma Group in 2007. RMG is a registry designed for the collection of clinical data concerning diagnosis, treatment, treatment results and survival of patients with monoclonal gammopathies. Data on patients with monoclonal gammopathy of undetermined significance (MGUS), Waldenström macroglobulinaemia (WM), multiple myeloma (MM) or primary AL ("amyloid light-chain") amyloidosis are collected in the registry. Nineteen Czech centres and four Slovak centres currently contribute to the registry. The registry currently contains records on more than 5,000 patients with MM, almost 3,000 patients with MGUS, 170 patients with WM and 26 patients with primary AL amyloidosis, i.e. more than 8,000 records on patients with monoclonal gammopathies altogether. This paper describes technology employed for the collection, storage and subsequent online visualisation of data. The CLADE-IS platform is introduced as a new system for the collection and storage of data from the registry. The form structure and functions of the new system are described for all diagnoses in general; these functions facilitate data entry to the registry and minimise the error rate in data. Publicly available online visualisations of data on patients with MGUS, WM, MM or primary AL amyloidosis from all Czech or Slovak centres are introduced, together with authenticated visualisations of data on patients with MM from selected centres. The RMG represents a data basis that makes it possible to monitor the disease course in patients with monoclonal gammopathies on the population level.Key words: Registry of Monoclonal Gammopathies - RMG - registries - monoclonal gammopathies - CLADE-IS - data visualisation - database.

Rapid screening of monoclonal antibodies: new 'microstick' radioimmunoassay

International Nuclear Information System (INIS)

Scheinberg, D.A.; Strand, M.; Wilsnack, R.

1983-01-01

A new system for assaying monoclonal antibodies consisting of an 8 x 12 array of sticks which fits into a 96-well microtiter plate is described. Tests using virus specific monoclonal antibodies and virus proteins demonstrated sensitivity equivalent to the conventional microtiter plate assay. Antibody production, antigen specific antibody, and immunoglobulin isotypes could be measured under sterile conditions directly in the original fusion mixture wells and much greater rapidity than with the microtiter plate assay. (Auth.)

Immunological Reactivity Using Monoclonal and Polyclonal Antibodies of Autoimmune Thyroid Target Sites with Dietary Proteins

Directory of Open Access Journals (Sweden)

Datis Kharrazian

2017-01-01

Full Text Available Many hypothyroid and autoimmune thyroid patients experience reactions with specific foods. Additionally, food interactions may play a role in a subset of individuals who have difficulty finding a suitable thyroid hormone dosage. Our study was designed to investigate the potential role of dietary protein immune reactivity with thyroid hormones and thyroid axis target sites. We identified immune reactivity between dietary proteins and target sites on the thyroid axis that includes thyroid hormones, thyroid receptors, enzymes, and transport proteins. We also measured immune reactivity of either target specific monoclonal or polyclonal antibodies for thyroid-stimulating hormone (TSH receptor, 5′deiodinase, thyroid peroxidase, thyroglobulin, thyroxine-binding globulin, thyroxine, and triiodothyronine against 204 purified dietary proteins commonly consumed in cooked and raw forms. Dietary protein determinants included unmodified (raw and modified (cooked and roasted foods, herbs, spices, food gums, brewed beverages, and additives. There were no dietary protein immune reactions with TSH receptor, thyroid peroxidase, and thyroxine-binding globulin. However, specific antigen-antibody immune reactivity was identified with several purified food proteins with triiodothyronine, thyroxine, thyroglobulin, and 5′deiodinase. Laboratory analysis of immunological cross-reactivity between thyroid target sites and dietary proteins is the initial step necessary in determining whether dietary proteins may play a potential immunoreactive role in autoimmune thyroid disease.

Identification of a second T-cell antigen receptor in human and mouse by an anti-peptide γ-chain-specific monoclonal antibody

International Nuclear Information System (INIS)

Ioannides, C.G.; Itoh, K.; Fox, F.E.; Pahwa, R.; Good, R.A.; Platsoucas, C.D.

1987-01-01

The authors developed a monoclonal antibody (mAb) (9D7) against a synthetic peptide (P13K) selected from the deduced amino acid sequence of the constant region of the λ chain of the murine T-cell antigen receptor (TCR) (amino acids 118-130). Using this mAb, they identified a putative second TCR expressed on peripheral blood lymphocytes from a patient with severe combined immunodeficiency (SCID) that were propagated in culture with recombinant interleukin 2 (rIL-2) and Con A. This mAb immunoprecipitated two polypeptide chains of 40 and 58 kDa under nonreducing conditions and of 40 and 56 kDa under reducing conditions from 125 I-labeled denatured lysates of T3 + WT31 - lymphocytes expanded in culture from a SCID patient. Chemical crosslinking of 125 I-labeled cells followed by immunoprecipitation with anti-Leu-4 mAb under nonreducing or reducing conditions revealed that the 40- and 56-kDa polypeptide chains were associated with the T3 differentiation antigen. These experiments were done with polyclonal cell populations. Cloned T3 + WT31 - cell populations are required to determine whether the TCR contains two λ polypeptide chains. Using the same 9D7 anti-P18K mAb and immunoblotting analysis, they identified a 35 kDa γ-chain polypeptide under reducing conditions expressed on purified L3T4 - Lyt2 - BALB/c mouse thymocytes. This γ-chain TCR is disulfide linked and has a molecular mass of 80 kDa under nonreducing conditions

Antitumor activity of ZD6126, a novel vascular-targeting agent, is enhanced when combined with ZD1839, an epidermal growth factor receptor tyrosine kinase inhibitor, and potentiates the effects of radiation in a human non-small cell lung cancer xenograft model.

Science.gov (United States)

Raben, David; Bianco, Cataldo; Damiano, Vincenzo; Bianco, Roberto; Melisi, Davide; Mignogna, Chiara; D'Armiento, Francesco Paolo; Cionini, Luca; Bianco, A Raffaele; Tortora, Giampaolo; Ciardiello, Fortunato; Bunn, Paul

2004-08-01

Targeting the tumor vasculature may offer an alternative or complementary therapeutic approach to targeting growth factor signaling in lung cancer. The aim of these studies was to evaluate the antitumor effects in vivo of the combination of ZD6126, a tumor-selective vascular-targeting agent; ZD1839 (gefitinib, Iressa), an epidermal growth factor receptor tyrosine kinase inhibitor; and ionizing radiation in the treatment of non-small cell lung cancer xenograft model. Athymic nude mice with established flank A549 human non-small cell lung cancer xenograft model xenografts were treated with fractionated radiation therapy, ZD6126, ZD1839, or combinations of each treatment. ZD6126 (150 mg/kg) was given i.p. the day after each course of radiation. Animals treated with ZD1839 received 100 mg/kg per dose per animal, 5 or 7 days/wk for 2 weeks. Immunohistochemistry was done to evaluate the effects on tumor growth using an anti-Ki67 monoclonal antibody. Effects on tumor-induced vascularization were quantified using an anti-factor VIII-related antigen monoclonal antibody. ZD6126 attenuated the growth of human A549 flank xenografts compared with untreated animals. Marked antitumor effects were observed when animals were treated with a combination of ZD6126 and fractionated radiation therapy with protracted tumor regression. ZD6126 + ZD1839 resulted in a greater tumor growth delay than either agent alone. Similar additive effects were seen with ZD1839 + fractionated radiation. Finally, the addition of ZD6126 to ZD1839 and radiation therapy seemed to further improve tumor growth control, with a significant tumor growth delay compared with animals treated with single agent or with double combinations. Immunohistochemistry showed that ZD1839 induced a marked reduction in A549 tumor cell proliferation. Both ZD1839 and ZD6126 treatment substantially reduced tumor-induced angiogenesis. ZD6126 caused marked vessel destruction through loss of endothelial cells and thrombosis

Molecular mechanism for the action of the anti-CD44 monoclonal antibody MEM-85

Czech Academy of Sciences Publication Activity Database

Škerlová, Jana; Král, Vlastimil; Kachala, M.; Fábry, Milan; Bumba, Ladislav; Svergun, D.I.; Tosner, Z.; Veverka, V.; Řezáčová, Pavlína

2015-01-01

Roč. 191, č. 2 (2015), s. 214-223 ISSN 1047-8477 R&D Projects: GA ČR(CZ) GA15-11851S EU Projects: European Commission 264257 Institutional support: RVO:68378050 ; RVO:61388971 Keywords : CD44 * Epitope mapping * Monoclonal antibody * MEM-85 * SAXS * NMR Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.570, year: 2015

Decreased numbers of chemotactic factor receptors in chronic neutropenia with defective chemotaxis: spontaneous recovery from the neutrophil abnormalities during early childhood

International Nuclear Information System (INIS)

Yasui, K.; Yamazaki, M.; Miyagawa, Y.; Komiyama, A.; Akabane, T.

1987-01-01

Childhood chronic neutropenia with decreased numbers of chemotactic factor receptors as well as defective chemotaxis was first demonstrated in an 8-month-old girl. Chemotactic factor receptors on neutrophils were assayed using tritiated N-formyl-methionyl-leucyl-phenylalanine ( 3 H-FMLP). The patient's neutrophils had decreased numbers of the receptors: numbers of the receptors were 20,000 (less than 3 SD) as compared with those of control cells of 52,000 +/- 6000 (mean +/- SD) (n = 10). The neutropenia disappeared spontaneously by 28 months of age parallel with the improvement of chemotaxis and increase in numbers of chemotactic factor receptors. These results demonstrate a transient decrease of neutrophil chemotactic factor receptors as one of the pathophysiological bases of a transient defect of neutrophil chemotaxis in this disorder

The combination of anti-KIR monoclonal antibodies with anti-PD-1/PD-L1 monoclonal antibodies could be a critical breakthrough in overcoming tumor immune escape in NSCLC

Directory of Open Access Journals (Sweden)

He YY

2018-04-01

Full Text Available Yayi He,1,2,* Sangtian Liu,1,* Jane Mattei,3 Paul A Bunn Jr,2 Caicun Zhou,1 Daniel Chan2 1Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, Shanghai, China; 2Division of Medical Oncology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA; 3Oncology Department, Moinhos de Vento Hospital, Porto Alegre, Brazil *These authors contributed equally to this work Background: The anti-programmed death-1 (PD-1/programmed death ligand-1 (PD-L1 monoclonal antibody has a good effect in the treatment of non-small cell lung cancer (NSCLC, but not all PD-1/PD-L1 positive patients can get benefit from it. Compensatory expression of other immune checkpoints may be correlated with the poor efficacy of anti-PD-1/PD-L1 monoclonal antibodies. The inhibitory human leukocyte antigen (HLA/killer cell Ig-like receptor (KIR can effectively block the killing effect of natural killer (NK cells on tumors. Our previous studies have confirmed that high expression of KIR was correlated with poor prognosis of NSCLC. Inhibitory KIR expression was positively correlated with the expression of PD-1. Methods: The expressions of KIR 2D (L1, L3, L4, S4 (BC032422/ADQ31987/NP_002246/NP_036446, Abcam and PD-1 (NAT 105, Cell marque proteins was assessed by immunohis­tochemistry. Results: The expression of inhibitory KIR in tumor cells or tumor infiltrating lymphocytes (TILs is associated with PD-1 expression. Among PD-1 positive patients, 76.3% were KIR 2D (L1, L3, L4, S4 positive on tumor cells, and 74.6% were KIR 2D (L1, L3, L4, S4 positive on TILs. We compared the expression of inhibitory KIR before and after treatment with nivolumab in 11 patients with NSCLC. We found that five (45.5% patients had positive expression of inhibitory KIR in tumor tissue after being treated with anti-PD-1 monoclonal antibodies, two of whom exhibited a significant

Development of a monoclonal-based enzyme-linked immunoassay for saxitoxin-induced protein.

Science.gov (United States)

Smith, D S; Kitts, D D

1994-03-01

A monoclonal antibody was generated against saxitoxin-induced protein (SIP) from the small shore crab Hemigrapsus oregenesis. SIP was induced by saxitoxin injection and could be detected in the crude crab extracts with both polyclonal and monoclonal antibody preparations. On Western blots, the polyclonal serum reacted against several bands which were induced by saxitoxin in the crude extracts. These bands represented proteins related to SIP. The monoclonal (4G5), however, was specific for the 79,000 mol. wt subunit of SIP. A triple antibody sandwich ELISA was developed in which polyclonal anti-SIP IgG was used as a trapping layer and monoclonal 4G5 was used as the detection layer. This assay was shown to be more specific and more accurate than a direct bind assay which employed the polyclonal antiserum alone. Although the polyclonal serum was more sensitive than the monoclonal on Western blots, the triple antibody sandwich and direct bind ELISAs were of comparable sensitivity.

Characterization of receptors for recombinant human tumor necrosis factor-alpha from human placental membranes

International Nuclear Information System (INIS)

Aiyer, R.A.; Aggarwal, B.B.

1990-01-01

High affinity receptors for recombinant human tumor necrosis factor-alpha (rhTNF-alpha) were identified on membranes prepared from full term human placenta. Highly purified rhTNF-alpha iodinated by the iodogen method was found to bind placental membranes in a displaceable manner with an approximate dissociation constant (KD) of 1.9 nM. The membrane bound TNF-alpha receptor could be solubilized by several detergents with optimum extraction being obtained with 1% Triton X-100. The binding of 125I-rhTNF-alpha to the solubilized receptor was found to be time and temperature dependent, yielding maximum binding within 1 h, 24 h and 48 h at 37 degrees C, 24 degrees C and 4 degrees C, respectively. However, the maximum binding obtainable at 4 degrees C was only 40% of that at 37 degrees C. The binding 125I-rhTNF-alpha to solubilized placental membrane extracts was displaceable by unlabeled rhTNF-alpha, but not by a related protein recombinant human tumor necrosis factor-beta (rhTNF-beta; previously called lymphotoxin). This is similar to the behavior of TNF-alpha receptors derived from detergent-solubilized cell extracts, although on intact cells, both rhTNF-alpha and rhTNF-beta bind with equal affinity to TNF receptors. The Scatchard analysis of the binding data of the solubilized receptor revealed high affinity binding sites with a KD of approximately 0.5 nM and a receptor concentration of about 1 pmole/mg protein. Gel filtration of the solubilized receptor-ligand complexes on Sephacryl S-300 revealed two different peaks of radioactivity at approximate molecular masses of 50,000 Da and 400,000 Da. The 400,000 dalton peak corresponded to the receptor-ligand complex. Overall, our results suggest that high affinity receptors for TNF-alpha are present on human placental membranes and provide evidence that these receptors may be different from that of rhTNF-beta

Tissue factor is an angiogenic-specific receptor for factor VII-targeted immunotherapy and photodynamic therapy.

Science.gov (United States)

Hu, Zhiwei; Cheng, Jijun; Xu, Jie; Ruf, Wolfram; Lockwood, Charles J

2017-02-01

Identification of target molecules specific for angiogenic vascular endothelial cells (VEC), the inner layer of pathological neovasculature, is critical for discovery and development of neovascular-targeting therapy for angiogenesis-dependent human diseases, notably cancer, macular degeneration and endometriosis, in which vascular endothelial growth factor (VEGF) plays a central pathophysiological role. Using VEGF-stimulated vascular endothelial cells (VECs) isolated from microvessels, venous and arterial blood vessels as in vitro angiogenic models and unstimulated VECs as a quiescent VEC model, we examined the expression of tissue factor (TF), a membrane-bound receptor on the angiogenic VEC models compared with quiescent VEC controls. We found that TF is specifically expressed on angiogenic VECs in a time-dependent manner in microvessels, venous and arterial vessels. TF-targeted therapeutic agents, including factor VII (fVII)-IgG1 Fc and fVII-conjugated photosensitizer, can selectively bind angiogenic VECs, but not the quiescent VECs. Moreover, fVII-targeted photodynamic therapy can selectively and completely eradicate angiogenic VECs. We conclude that TF is an angiogenic-specific receptor and the target molecule for fVII-targeted therapeutics. This study supports clinical trials of TF-targeted therapeutics for the treatment of angiogenesis-dependent diseases such as cancer, macular degeneration and endometriosis.

The original Pathologische Anatomie Leiden-Endothelium monoclonal antibody recognizes a vascular endothelial growth factor binding site within neuropilin-1

NARCIS (Netherlands)

Jaalouk, Diana E.; Ozawa, Nfichael G.; Sun, Jessica; Lahdenranta, Johanna; Schlingemann, Reinier O.; Pasqualini, Renata; Arap, Wadih

2007-01-01

For two decades, the antigen recognized by the Pathologische Anatomie Leiden-Endothelium (PAL-E) monoclonal antibody, a standard vascular endothelial cell marker, has remained elusive. Here, we used a combinatorial phage display-based approach ("epitope mapping") to select peptides binding to the

Rat Monoclonal Antibodies Specific for LST1 Proteins

OpenAIRE

Schiller, Christian; Nitschké, Maximilian J. E.; Seidl, Alexander; Kremmer, Elisabeth; Weiss, Elisabeth H.

2009-01-01

The LST1 gene is located in the human MHC class III region and encodes transmembrane and soluble isoforms that have been suggested to play a role in the regulation of the immune response and are associated with inflammatory diseases such as rheumatoid arthritis. Here we describe the generation and characterization of the first monoclonal antibodies against LST1. Two hybridoma lines secreting monoclonal antibodies designated 7E2 and 8D12 were established. The 7E2 antibody detects recombinant a...

Neurotrophin receptors expression and JNK pathway activation in human astrocytomas

International Nuclear Information System (INIS)

Assimakopoulou, Martha; Kondyli, Maria; Gatzounis, George; Maraziotis, Theodore; Varakis, John

2007-01-01

Neurotrophins are growth factors that regulate cell growth, differentiation and apoptosis in the nervous system. Their diverse actions are mediated through two different transmembrane – receptor signaling systems: Trk receptor tyrosine kinases (TrkA, TrkB, TrkC) and p75 NTR neurotrophin receptor. Trk receptors promote cell survival and differentiation while p75 NTR induces, in most cases, the activity of JNK-p53-Bax apoptosis pathway or suppresses intracellular survival signaling cascades. Robust Trk activation blocks p75 NTR -induced apoptosis by suppressing the JNK-p53-Bax pathway. The aim of this exploratory study was to investigate the expression levels of neurotrophin receptors, Trks and p75 NTR , and the activation of JNK pathway in human astrocytomas and in adjacent non-neoplastic brain tissue. Formalin-fixed paraffin-embedded serial sections from 33 supratentorial astrocytomas (5 diffuse fibrillary astrocytomas, WHO grade II; 6 anaplastic astrocytomas, WHO grade III; 22 glioblastomas multiforme, WHO grade IV) were immunostained following microwave pretreatment. Polyclonal antibodies against TrkA, TrkB, TrkC and monoclonal antibodies against p75 NTR and phosphorylated forms of JNK (pJNK) and c-Jun (pc-Jun) were used. The labeling index (LI), defined as the percentage of positive (labeled) cells out of the total number of tumor cells counted, was determined. Moderate to strong, granular cytoplasmic immunoreactivity for TrkA, TrkB and TrkC receptors was detected in greater than or equal to 10% of tumor cells in the majority of tumors independently of grade; on the contrary, p75 NTR receptor expression was found in a small percentage of tumor cells (~1%) in some tumors. The endothelium of tumor capillaries showed conspicuous immunoreactivity for TrkB receptor. Trk immunoreactivity seemed to be localized in some neurons and astrocytes in non-neoplastic tissue. Phosphorylated forms of JNK (pJNK) and c-Jun (pc-Jun) were significantly co-expressed in a tumor

A Plant Immune Receptor Detects Pathogen Effectors that Target WRKY Transcription Factors.

Science.gov (United States)

Sarris, Panagiotis F; Duxbury, Zane; Huh, Sung Un; Ma, Yan; Segonzac, Cécile; Sklenar, Jan; Derbyshire, Paul; Cevik, Volkan; Rallapalli, Ghanasyam; Saucet, Simon B; Wirthmueller, Lennart; Menke, Frank L H; Sohn, Kee Hoon; Jones, Jonathan D G

2015-05-21

Defense against pathogens in multicellular eukaryotes depends on intracellular immune receptors, yet surveillance by these receptors is poorly understood. Several plant nucleotide-binding, leucine-rich repeat (NB-LRR) immune receptors carry fusions with other protein domains. The Arabidopsis RRS1-R NB-LRR protein carries a C-terminal WRKY DNA binding domain and forms a receptor complex with RPS4, another NB-LRR protein. This complex detects the bacterial effectors AvrRps4 or PopP2 and then activates defense. Both bacterial proteins interact with the RRS1 WRKY domain, and PopP2 acetylates lysines to block DNA binding. PopP2 and AvrRps4 interact with other WRKY domain-containing proteins, suggesting these effectors interfere with WRKY transcription factor-dependent defense, and RPS4/RRS1 has integrated a "decoy" domain that enables detection of effectors that target WRKY proteins. We propose that NB-LRR receptor pairs, one member of which carries an additional protein domain, enable perception of pathogen effectors whose function is to target that domain. Copyright © 2015 Elsevier Inc. All rights reserved.

Exploration of novel strategies to enhance monoclonal antibodies targeting

International Nuclear Information System (INIS)

Khawli, L.A.; Epstein, A.L.

1997-01-01

This paper highlights the major obstacles and prospects of antibody targeting for the radio imaging and therapy of human malignant lymphomas and more challenging solid tumors. To improve the therapeutic potential of monoclonal antibodies, the authors have focused their attention on the development of new and successful methods to augment antibody uptake in the tumor. These approaches include the use of radiolabeled streptavidin to target biotinylated monoclonal antibodies already bound to tumor, pretreatment with vasoactive immunoconjugates, and the use of chemically modified antibodies. Because of the promising preclinical data obtained with these three newer approaches, plans are underway to test them in the clinic. More generally, these approaches are applicable to the use of other monoclonal antibody/tumor systems for the diagnosis and therapy of human cancers and related diseases

Expression of Vascular Endothelial Growth Factor Receptors in Benign Vascular Lesions of the Orbit: A Case Series.

Science.gov (United States)

Atchison, Elizabeth A; Garrity, James A; Castillo, Francisco; Engman, Steven J; Couch, Steven M; Salomão, Diva R

2016-01-01

Vascular lesions of the orbit, although not malignant, can cause morbidity because of their location near critical structures in the orbit. For the same reason, they can be challenging to remove surgically. Anti-vascular endothelial growth factor (VEGF) drugs are increasingly being used to treat diseases with prominent angiogenesis. Our study aimed to determine to what extent VEGF receptors and their subtypes are expressed on selected vascular lesions of the orbit. Retrospective case series of all orbital vascular lesions removed by one of the authors (JAG) at the Mayo Clinic. A total of 52 patients who underwent removal of vascular orbital lesions. The pathology specimens from the patients were retrieved, their pathologic diagnosis was confirmed, demographic and clinical information were gathered, and sections from vascular tumors were stained with vascular endothelial growth factor receptor (VEGFR), vascular endothelial growth factor receptor type 1 (VEGFR1), vascular endothelial growth factor receptor type 2 (VEGFR2), and vascular endothelial growth factor receptor type 3 (VEGFR3). The existence and pattern of staining with VEGF and its subtypes on these lesions. There were 28 specimens of venous malformations, 4 capillary hemangiomas, 7 lymphatic malformations, and 6 lymphaticovenous malformations. All samples stained with VEGF, 55% stained with VEGFR1, 98% stained with VEGFR2, and 96% stained with VEGFR3. Most (94%) of the VEGFR2 staining was diffuse. Most orbital vascular lesions express VEGF receptors, which may suggest a future target for nonsurgical treatment. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Monoclonal antibodies for use in an immunoradiometric assay for α-foetoprotein

International Nuclear Information System (INIS)

Hunter, W.M.; Bennie, J.G.

1982-01-01

The advantages offered by a mouse IgG 1 monoclonal antibody to human α-foetoprotein (AFP) for the preparation of [ 125 I]antibody for use in an immunoradiometric assay (IRMA) have been investigated. The antibody was isolated from ascites fluid by sodium sulphate precipitation followed by gel filtration on Sephadex G-200. The freeze-dried powder and solutions thereof were stable and were used for iodination to 1 atom 125 I/molecule antibody by the chloramine-T procedure. At high antigen concentrations 70-80% of the added [ 125 ]Ab was present in the sandwich. Linear response curves in the range 1-100 μg antigen/l incubate were obtained when [ 125 I]Ab was in slight excess. In this region an Ag : Ab ratio 1.9 : 1 was obtained which is consistent with the saturation of a bifunctional antibody. Although non-specific binding (in the absence of antigen) was consistently 125 I]Ab, this was the main factor in determining assay detection limits. The serum AFP levels from both non-pregnant and pregnant subjects as measured by the IRMA using the [ 125 I]monoclonal Ab and by radioimmunoassay (RIA) using a sheep antiserum to AFP were in excellent agreement. The IRMA was manipulatively simple, employed a shorter incubation time (2h), required shorter counting times than the RIA and gave a much wider working range. The provision of a monoclonal antibody for labelling removes the one major practicability barrier which otherwise limits the development and use of the potentially superior IRMA system. (Auth.)

Single-domain antibodies that compete with the natural ligand fibroblast growth factor block the internalization of the fibroblast growth factor receptor 1

Energy Technology Data Exchange (ETDEWEB)

Veggiani, Gianluca; Ossolengo, Giuseppe; Aliprandi, Marisa; Cavallaro, Ugo [IFOM-IEO Campus, Via Adamello 16, 20139 Milano (Italy); Marco, Ario de, E-mail: ario.demarco@ung.si [IFOM-IEO Campus, Via Adamello 16, 20139 Milano (Italy); Dept. Environmental Sciences, University of Nova Gorica (UNG), Vipavska 13, P.O. Box 301-SI-5000, Rozna Dolina, Nova Gorica (Slovenia)

2011-05-20

Highlights: {yields} Recombinant antibodies for FGFR1 were isolated from a llama naive library in VHH format. {yields} These antibodies compete with the natural ligand FGF-2 for the same epitope on FGFR1. {yields} The antibody competition inhibits the FGF-2-dependent internalization of FGFR1. -- Abstract: Single-domain antibodies in VHH format specific for fibroblast growth factor receptor 1 (FGFR1) were isolated from a phage-display llama naive library. In particular, phage elution in the presence of the natural receptor ligand fibroblast growth factor (FGF) allowed for the identification of recombinant antibodies that compete with FGF for the same region on the receptor surface. These antibodies posses a relatively low affinity for FGFR1 and were never identified when unspecific elution conditions favoring highly affine binders were applied to panning procedures. Two populations of competitive antibodies were identified that labeled specifically the receptor-expressing cells in immunofluorescence and recognize distinct epitopes. Antibodies from both populations effectively prevented FGF-dependent internalization and nuclear accumulation of the receptor in cultured cells. This achievement indicates that these antibodies have a capacity to modulate the receptor physiology and, therefore, constitute powerful reagents for basic research and a potential lead for therapeutic applications.

Single-domain antibodies that compete with the natural ligand fibroblast growth factor block the internalization of the fibroblast growth factor receptor 1

International Nuclear Information System (INIS)

Veggiani, Gianluca; Ossolengo, Giuseppe; Aliprandi, Marisa; Cavallaro, Ugo; Marco, Ario de

2011-01-01

Highlights: → Recombinant antibodies for FGFR1 were isolated from a llama naive library in VHH format. → These antibodies compete with the natural ligand FGF-2 for the same epitope on FGFR1. → The antibody competition inhibits the FGF-2-dependent internalization of FGFR1. -- Abstract: Single-domain antibodies in VHH format specific for fibroblast growth factor receptor 1 (FGFR1) were isolated from a phage-display llama naive library. In particular, phage elution in the presence of the natural receptor ligand fibroblast growth factor (FGF) allowed for the identification of recombinant antibodies that compete with FGF for the same region on the receptor surface. These antibodies posses a relatively low affinity for FGFR1 and were never identified when unspecific elution conditions favoring highly affine binders were applied to panning procedures. Two populations of competitive antibodies were identified that labeled specifically the receptor-expressing cells in immunofluorescence and recognize distinct epitopes. Antibodies from both populations effectively prevented FGF-dependent internalization and nuclear accumulation of the receptor in cultured cells. This achievement indicates that these antibodies have a capacity to modulate the receptor physiology and, therefore, constitute powerful reagents for basic research and a potential lead for therapeutic applications.

Immunohistochemical detection of estrogen receptors in canine mammary tumors

Directory of Open Access Journals (Sweden)

Elena Atanaskova Petrov

2016-03-01

Full Text Available Mammary tumors are among the most common neoplasms in intact female dogs.They have a complex morphology, usually affecting middle age and older bitches. Almost 50% of the mammary tumors in dogs are malignant neoplasms. Prognosis is based on several factors: stage, age, tumor size, metastasis, histopathology, ovariectomy status and hormone-receptor activity. Immunohistochemical (IHC measurement has become increasingly an important diagnostic and prognostic parameter, with the development of monoclonal antibodies against nuclear estrogen and progestin receptors. The aim of this study was to detect the presence of ER receptors in malignant canine mammary tumors and to identify their association with the clinical course of the tumor. Mammary tumor samples have been obtained by mastectomy from dogs presented at our clinic. Detailed clinical examination, CBC and basic serum biochemical profile were performed in all patients. Surgery was the only treatment. Histopathological examination and immunohistochemical detection of estrogen α receptors (ERα was performed on 8 formalin-fixed, paraffin-embedded tissue samples, using the PT LINK immunoperoxidase technique. Histopathological examination of the mammary tumor samples (n=11 revealed tubular adenocarcinoma (n=6,54.5% and ductal adenocarcinoma (n=3, 27.3%, one patient with benign adenoma and one with mastitis. Patients with positive ER tumors are alive, without remission, while 3 of the patients that were ER negative died due to lung metastases. According to our results, it can be concluded that the appearance and development of canine mammary tumors is highly connected with ovarian steroid hormones and that immunostaining of the tumors may be used as a good prognostic parameter in these patients.

Prevalence and type of monoclonal gammopathy of undetermined significance in an apparently healthy Nigerian population: a cross sectional study.

Science.gov (United States)

Onwah, A Lawretta; Adeyemo, Titilope A; Adediran, Adewumi; Ajibola, Sarah O; Akanmu, Alani S

2012-06-28

The prevalence of monoclonal gammopathy of undetermined significance (MGUS), a premalignant plasma-cell disorder has not been determined in our geographic area Nigeria. A cross sectional survey was carried on apparently healthy Nigerians selected by multistage sampling technique from the cosmopolitan city of Lagos, Nigeria. Subjects enrolled into the study had 2-step screening for the presence, type and concentration of monoclonal band. Agarose-gel electrophoresis was performed on all serum samples, and any serum sample with a discrete band of monoclonal protein or thought to have a localized band was subjected to Immunofixation. Subjects were also evaluated for Bence jones proteinuria, haematological and biochemical parameters. Four hundred and ten subjects with a mean age of 45.68 ± 10.3 years, a median of 45.00 years and a range of 20 to 80 years were enrolled into the study. MGUS was identified in only one (0.24 percent) of the 410 study subject. This subject was demonstrated to have a double monoclonal gammopathy; IgGλ at 16.9 g/L and IgAκ at 8.5 g/L. None of them including the sole subject with MGUS had a monoclonal urinary light chain. Among residents of Lagos, Nigeria, MGUS was found in only 0.24% percent of apparently normal persons with a median age of 45 years. This suggests that MGUS which represents the earliest stage of monoclonal plasma/lymphoid cell proliferation is not a common finding in the relatively young population of Nigeria. Future epidemiologic studies dealing with plasma cell disorders in older people are required to carefully examine the relationship between environmental factors and prevalence of MGUS and its ultimate progression to MM.

Receptors for insulin-like growth factors I and II: autoradiographic localization in rat brain and comparison to receptors for insulin

International Nuclear Information System (INIS)

Lesniak, M.A.; Hill, J.M.; Kiess, W.; Rojeski, M.; Pert, C.B.; Roth, J.

1988-01-01

Receptors for insulin-like growth factor I (IGF-I) in rat brain were visualized using autoradiography with [125I]IGF-I. The binding of the labeled peptide was competed for fully by high concentrations of unlabeled IGF-I. At intermediate concentrations of unlabeled peptide the binding of [125I]IGF-I was competed for by unlabeled IGF-I more effectively than by IGF-II or insulin, which is typical of receptors for IGF-I. Essentially every brain section shows specific binding of IGF-I, and the pattern of binding of IGF-I to its receptors correlated well with the cytoarchitectonic structures. In parallel studies we showed that [125I]IGF-II was bound to tissue sections of rat brain and that the binding was competed for by an excess of unlabeled IGF-II. However, intermediate concentrations of unlabeled peptides gave inconclusive results. To confirm that the binding of [125I]IGF-II was to IGF-II receptors, we showed that antibodies specific for the IGF-II receptor inhibited the binding of labeled IGF-II. Furthermore, the binding of the antibody to regions of the brain section, visualized by the application of [125I]protein-A, gave patterns indistinguishable from those obtained with [125I]IGF-II alone. Again, the binding was very widely distributed throughout the central nervous system, and the patterns of distribution corresponded well to the underlying neural structures. Densitometric analysis of the receptors enabled us to compare the distribution of IGF-I receptors with that of IGF-II receptors as well as retrospectively with that of insulin receptors

Increased Eps15 homology domain 1 and RAB11FIP3 expression regulate breast cancer progression via promoting epithelial growth factor receptor recycling.

Science.gov (United States)

Tong, Dandan; Liang, Ya-Nan; Stepanova, A A; Liu, Yu; Li, Xiaobo; Wang, Letian; Zhang, Fengmin; Vasilyeva, N V

2017-02-01

Recent research indicates that the C-terminal Eps15 homology domain 1 is associated with epithelial growth factor receptor-mediated endocytosis recycling in non-small-cell lung cancer. The aim of this study was to determine the clinical significance of Eps15 homology domain 1 gene expression in relation to phosphorylation of epithelial growth factor receptor expression in patients with breast cancer. Primary breast cancer samples from 306 patients were analyzed for Eps15 homology domain 1, RAB11FIP3, and phosphorylation of epithelial growth factor receptor expression via immunohistochemistry. The clinical significance was assessed via a multivariate Cox regression analysis, Kaplan-Meier curves, and the log-rank test. Eps15 homology domain 1 and phosphorylation of epithelial growth factor receptor were upregulated in 60.46% (185/306) and 53.92% (165/306) of tumor tissues, respectively, as assessed by immunohistochemistry. The statistical correlation analysis indicated that Eps15 homology domain 1 overexpression was positively correlated with the increases in phosphorylation of epithelial growth factor receptor ( r = 0.242, p breast cancer for the overall survival in the total, chemotherapy, and human epidermal growth factor receptor 2 (-) groups. However, the use of combined expression of Eps15 homology domain 1 and phosphorylation of epithelial growth factor receptor markers is more effective for the disease-free survival in the overall population, chemotherapy, and human epidermal growth factor receptor 2 (-) groups. Moreover, the combined markers are also significant prognostic markers of breast cancer in the human epidermal growth factor receptor 2 (+), estrogen receptor (+), and estrogen receptor (-) groups. Eps15 homology domain 1 has a tumor suppressor function, and the combined marker of Eps15 homology domain 1/phosphorylation of epithelial growth factor receptor expression was identified as a better prognostic marker in breast cancer diagnosis

The beta-glucan receptor dectin-1 recognizes specific morphologies of Aspergillus fumigatus.

Directory of Open Access Journals (Sweden)

Chad Steele

2005-12-01

Full Text Available Alveolar macrophages represent a first-line innate host defense mechanism for clearing inhaled Aspergillus fumigatus from the lungs, yet contradictory data exist as to which alveolar macrophage recognition receptor is critical for innate immunity to A. fumigatus. Acknowledging that the A. fumigatus cell wall contains a high beta-1,3-glucan content, we questioned whether the beta-glucan receptor dectin-1 played a role in this recognition process. Monoclonal antibody, soluble receptor, and competitive carbohydrate blockage indicated that the alveolar macrophage inflammatory response, specifically the production of tumor necrosis factor-alpha (TNF-alpha, interleukin-1alpha (IL-1alpha, IL-1beta, IL-6, CXCL2/macrophage inflammatory protein-2 (MIP-2, CCL3/macrophage inflammatory protein-1alpha (MIP-1alpha, granulocyte-colony stimulating factor (G-CSF, and granulocyte monocyte-CSF (GM-CSF, to live A. fumigatus was dependent on recognition via the beta-glucan receptor dectin-1. The inflammatory response was triggered at the highest level by A. fumigatus swollen conidia and early germlings and correlated to the levels of surface-exposed beta glucans, indicating that dectin-1 preferentially recognizes specific morphological forms of A. fumigatus. Intratracheal administration of A. fumigatus conidia to mice in the presence of a soluble dectin-Fc fusion protein reduced both lung proinflammatory cytokine/chemokine levels and cellular recruitment while modestly increasing the A. fumigatus fungal burden, illustrating the importance of beta-glucan-initiated dectin-1 signaling in defense against this pathogen. Collectively, these data show that dectin-1 is centrally required for the generation of alveolar macrophage proinflammatory responses to A. fumigatus and to our knowledge provides the first in vivo evidence for the role of dectin-1 in fungal innate defense.

Adenosine inhibits neutrophil vascular endothelial growth factor release and transendothelial migration via A2B receptor activation.

LENUS (Irish Health Repository)

Wakai, A

2012-02-03

The effects of adenosine on neutrophil (polymorphonuclear neutrophils; PMN)-directed changes in vascular permeability are poorly characterized. This study investigated whether adenosine modulates activated PMN vascular endothelial growth factor (vascular permeability factor; VEGF) release and transendothelial migration. PMN activated with tumour necrosis factor-alpha (TNF-alpha, 10 ng\\/mL) were incubated with adenosine and its receptor-specific analogues. Culture supernatants were assayed for VEGF. PMN transendothelial migration across human umbilical vein endothelial cell (HUVEC) monolayers was assessed in vitro. Adhesion molecule receptor expression was assessed flow cytometrically. Adenosine and some of its receptor-specific analogues dose-dependently inhibited activated PMN VEGF release. The rank order of potency was consistent with the affinity profile of human A2B receptors. The inhibitory effect of adenosine was reversed by 3,7-dimethyl-1-propargylxanthine, an A2 receptor antagonist. Adenosine (100 microM) or the A2B receptor agonist 5\\'-N-ethylcarboxamidoadenosine (NECA, 100 microM) significantly reduced PMN transendothelial migration. However, expression of activated PMN beta2 integrins and HUVEC ICAM-1 were not significantly altered by adenosine or NECA. Adenosine attenuates human PMN VEGF release and transendothelial migration via the A2B receptor. This provides a novel target for the modulation of PMN-directed vascular hyperpermeability in conditions such as the capillary leak syndrome.

Development of an Anti-HER2 Monoclonal Antibody H2Mab-139 Against Colon Cancer.

Science.gov (United States)

Kaneko, Mika K; Yamada, Shinji; Itai, Shunsuke; Kato, Yukinari

2018-02-01

Human epidermal growth factor receptor 2 (HER2) expression has been reported in several cancers, such as breast, gastric, lung, pancreatic, and colorectal cancers. HER2 is overexpressed in those cancers and is associated with poor clinical outcomes. Trastuzumab, a humanized anti-HER2 antibody, provides significant survival benefits for patients with HER2-overexpressing breast cancers and gastric cancers. In this study, we developed a novel anti-HER2 monoclonal antibody (mAb), H 2 Mab-139 (IgG 1 , kappa) and investigated it against colon cancers using flow cytometry, western blot, and immunohistochemical analyses. Flow cytometry analysis revealed that H 2 Mab-139 reacted with colon cancer cell lines, such as Caco-2, HCT-116, HCT-15, HT-29, LS 174T, COLO 201, COLO 205, HCT-8, SW1116, and DLD-1. Although H 2 Mab-139 strongly reacted with LN229/HER2 cells on the western blot, we did not observe a specific signal for HER2 in colon cancer cell lines. Immunohistochemical analyses revealed sensitive and specific reactions of H 2 Mab-139 against colon cancers, indicating that H 2 Mab-139 is useful in detecting HER2 overexpression in colon cancers using flow cytometry and immunohistochemical analyses.

Effects of Monoclonal Antibody Cetuximab on Proliferation of Non-small Cell Lung Cancer Cell lines

Directory of Open Access Journals (Sweden)

Zhen CHEN

2010-08-01

Full Text Available Background and objective The epidermal growth factor receptor (EGFR monoclonal antibody cetuximab has been used widely in non-small cell lung cancer patients. The aim of this study is to explore the effect of lung cancer cells (A549, H460, H1299, SPC-A-1 which were treated by cetuximab in vitro. Methods We studied the effects of increasing concentrations of cetuximab (1 nmol/L-625 nmol/L in four human lung cancer cell lines (A549, SPC-A-1, H460, H1229. CCK8 measured the inhibition of cell proliferation in each group. A549, SPC-A-1 were marked by PI and the statuses of apoptosis were observed. Western blot were used to detect the proliferation-related signaling protein and apoptosis-related protein in A549. Results The treatment with cetuximab resulted in the effect on cell proliferation and apoptosis in a time- and dosedependent manner. The expression of activated key enzymes (p-AKT, p-EGFR, p-MAPK in EGFR signaling transduction pathway were down-regulated more obviously. Conclusion Cetuximab is an effective targeted drug in the treatment of lung cancer cell lines, tissues, most likely to contribute to the inhibition of key enzymes in EGFR signaling transduction pathway.

Nonclinical safety of mavrilimumab, an anti-GMCSF receptor alpha monoclonal antibody, in cynomolgus monkeys: Relevance for human safety

Energy Technology Data Exchange (ETDEWEB)

Ryan, Patricia C., E-mail: ryanp@medimmune.com [MedImmune, LLC, Gaithersburg, MD (United States); Sleeman, Matthew A. [MedImmune, LLC, Cambridge (United Kingdom); Rebelatto, Marlon [MedImmune, LLC, Gaithersburg, MD (United States); Wang, Bing; Lu, Hong [MedImmune, LLC, Moutain View, CA (United States); Chen, Xiaomin [Novartis, East Hanover, NJ (United States); Wu, Chi-Yuan [MedImmune, LLC, Moutain View, CA (United States); Hinrichs, Mary Jane; Roskos, Lorin [MedImmune, LLC, Gaithersburg, MD (United States); Towers, Heidi [MedImmune, LLC, Cambridge (United Kingdom); McKeever, Kathleen; Dixit, Rakesh [MedImmune, LLC, Gaithersburg, MD (United States)

2014-09-01

Mavrilimumab (CAM-3001) is an investigational human IgG4 monoclonal antibody (MAb) targeting GM-CSF receptor alpha which is currently being developed for the treatment of RA. GM-CSF plays a central role in the pathogenesis of rheumatoid arthritis (RA) through the activation, differentiation, and survival of macrophages and neutrophils. To support clinical development, the nonclinical safety of mavrilimumab was evaluated in several studies with cynomolgus monkeys as the pharmacologically relevant species. Comprehensive toxicity parameters were assessed in each study, and treatment duration ranged from 4 to 26 weeks. Mavrilimumab has an acceptable safety profile in monkeys with no changes in any parameters other than microscopic findings in lung. In several studies, minimal accumulation of foamy alveolar macrophages was observed. This finding was only seen in studies of at least 11 weeks duration, was reversible following a dose-free recovery period and was considered non-adverse. At higher dose levels (≥ 30 mg/kg/week), in a 26-week repeat-IV dose study, the presence of lung foreign material, cholesterol clefts, and granulomatous inflammation was also observed in a few animals and was considered adverse. The dose- and time-related accumulation of foamy macrophages in lung following exposure to mavrilimumab observed in several NHP studies was expected based upon the known role of GM-CSFRα signaling in the function of alveolar macrophages. Overall, a clean no-observed-adverse-effect-level (NOAEL) without any effects in lung was established and provided adequate clinical safety margins. In clinical studies in RA patients, mavrilimumab has demonstrated good clinical activity with adequate safety to support further clinical development. A Phase 2b study of mavrilimumab in subjects with RA is in progress. - Highlights: • Mavrilimumab is a MAB targeting GM-CSFRα being developed for RA therapy. • Mavrilimumab has an acceptable safety profile in cynomolgus monkeys. �

Nonclinical safety of mavrilimumab, an anti-GMCSF receptor alpha monoclonal antibody, in cynomolgus monkeys: Relevance for human safety

International Nuclear Information System (INIS)

Ryan, Patricia C.; Sleeman, Matthew A.; Rebelatto, Marlon; Wang, Bing; Lu, Hong; Chen, Xiaomin; Wu, Chi-Yuan; Hinrichs, Mary Jane; Roskos, Lorin; Towers, Heidi; McKeever, Kathleen; Dixit, Rakesh

2014-01-01

Mavrilimumab (CAM-3001) is an investigational human IgG4 monoclonal antibody (MAb) targeting GM-CSF receptor alpha which is currently being developed for the treatment of RA. GM-CSF plays a central role in the pathogenesis of rheumatoid arthritis (RA) through the activation, differentiation, and survival of macrophages and neutrophils. To support clinical development, the nonclinical safety of mavrilimumab was evaluated in several studies with cynomolgus monkeys as the pharmacologically relevant species. Comprehensive toxicity parameters were assessed in each study, and treatment duration ranged from 4 to 26 weeks. Mavrilimumab has an acceptable safety profile in monkeys with no changes in any parameters other than microscopic findings in lung. In several studies, minimal accumulation of foamy alveolar macrophages was observed. This finding was only seen in studies of at least 11 weeks duration, was reversible following a dose-free recovery period and was considered non-adverse. At higher dose levels (≥ 30 mg/kg/week), in a 26-week repeat-IV dose study, the presence of lung foreign material, cholesterol clefts, and granulomatous inflammation was also observed in a few animals and was considered adverse. The dose- and time-related accumulation of foamy macrophages in lung following exposure to mavrilimumab observed in several NHP studies was expected based upon the known role of GM-CSFRα signaling in the function of alveolar macrophages. Overall, a clean no-observed-adverse-effect-level (NOAEL) without any effects in lung was established and provided adequate clinical safety margins. In clinical studies in RA patients, mavrilimumab has demonstrated good clinical activity with adequate safety to support further clinical development. A Phase 2b study of mavrilimumab in subjects with RA is in progress. - Highlights: • Mavrilimumab is a MAB targeting GM-CSFRα being developed for RA therapy. • Mavrilimumab has an acceptable safety profile in cynomolgus monkeys. �

Sperm Impairment by Sperm Agglutinating Factor Isolated from Escherichia coli: Receptor Specific Interactions

Directory of Open Access Journals (Sweden)

Kiranjeet Kaur

2013-01-01

Full Text Available In an earlier work done in our laboratory, we have been able to isolate a sperm agglutinating strain of Escherichia coli from the semen sample of a male attending infertility clinic. Further, factor responsible for sperm agglutination (SAF was isolated and purified, and, using SAF as a tool, corresponding SAF binding receptor from human spermatozoa has been purified. Characterization of SAF and SAF binding receptor using MALDI-TOF showed homology to glutamate decarboxylase and MHC class I molecule, respectively. Coincubation of SAF with spermatozoa not only resulted in spermagglutination but could also compromise other sperm parameters, namely, Mg2+ dependent ATPase activity and apoptosis. Intravaginal administration of SAF could lead to infertility in Balb/c mice. SAF induced impairment of sperm parameters, and infertility was observed to be due to interaction of SAF with sperm surface receptor component as, when purified receptor was introduced, receptor completely inhibited all the detrimental effects induced by SAF. From these results, it could be concluded that interaction of SAF with spermatozoa is receptor mediated.

Monoclonal antibodies in the treatment of metastatic colorectal cancer: a review

NARCIS (Netherlands)

Tol, Jolien; Punt, Cornelis J. A.

2010-01-01

Two groups of agents targeting either the vascular endothelial growth factor (VEGF) receptor or the epidermal growth factor receptor (EGFR) have been added to the therapeutic arsenal against metastatic colorectal cancer (mCRC). Currently available agents in these groups are the anti-VEGF antibody

Monoclonal antibodies in the treatment of metastatic colorectal cancer: a review.

NARCIS (Netherlands)

Tol, J.; Punt, C.J.A.

2010-01-01

BACKGROUND: Two groups of agents targeting either the vascular endothelial growth factor (VEGF) receptor or the epidermal growth factor receptor (EGFR) have been added to the therapeutic arsenal against metastatic colorectal cancer (mCRC). Currently available agents in these groups are the anti-VEGF

Insulin-like growth factor receptor inhibitors: baby or the bathwater?

Science.gov (United States)

Yee, Douglas

2012-07-03

The success of targeted therapies for cancer is undisputed; strong preclinical evidence has resulted in the approval of several new agents for cancer treatment. The type I insulin-like growth factor receptor (IGF1R) appeared to be one of these promising new targets. Substantial population and preclinical data have all pointed toward this pathway as an important regulator of tumor cell biology. Although early results from clinical trials that targeted the IGF1R showed some evidence of response, larger randomized phase III trials have not shown clear clinical benefit of targeting this pathway in combination with conventional strategies. These disappointing results have resulted in the discontinuation of several anti-IGF1R programs. However, the conduct of these trials has brought to the forefront several important factors that need to be considered in the conduct of future clinical trials. The need to develop biomarkers, a clearer understanding of insulin receptor function, and defining rational combination regimens all require further consideration. In this commentary, the current state of IGF1R inhibitors in cancer therapy is reviewed.

Immunolocalization of progesterone receptors in binucleate trophoblast cells of the buffalo placenta (Bubalus bubalis

Directory of Open Access Journals (Sweden)

Carlos Eduardo Ambrósio

2007-06-01

Full Text Available The binucleate trophoblast cells (CTBs of the water buffalo placenta (Bubalus bubalis were studied with emphasis on the presence of progesterone receptor. Placentomal tissues from 27 buffalos (2-10 months of pregnancy were processed and embedded in paraplast (Paraplast Embedding Media – Paraplast Plus to locate the progesterone receptors using the immunohistochemistry technique. The immunohistochemical reaction for progesterone receptor through monoclonal antibody PgR Ab2 showed staining of CTBs, caruncular epithelial and estromal cells and blood vessel estromal pericitos present in the placentome throughout the entire gestational period analyzed. These results indicate the production of progesterone with autocrine and paracrine action in the placentome growth, differentiation and functional regulation.

Identification of antibody glycosylation structures that predict monoclonal antibody Fc-effector function.

Science.gov (United States)

Chung, Amy W; Crispin, Max; Pritchard, Laura; Robinson, Hannah; Gorny, Miroslaw K; Yu, Xiaojie; Bailey-Kellogg, Chris; Ackerman, Margaret E; Scanlan, Chris; Zolla-Pazner, Susan; Alter, Galit

2014-11-13

To determine monoclonal antibody (mAb) features that predict fragment crystalizable (Fc)-mediated effector functions against HIV. Monoclonal antibodies, derived from Chinese hamster ovary cells or Epstein-Barr virus-immortalized mouse heteromyelomas, with specificity to key regions of the HIV envelope including gp120-V2, gp120-V3 loop, gp120-CD4(+) binding site, and gp41-specific antibodies, were functionally profiled to determine the relative contribution of the variable and constant domain features of the antibodies in driving robust Fc-effector functions. Each mAb was assayed for antibody-binding affinity to gp140(SR162), antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP) and for the ability to bind to FcγRIIa, FcγRIIb and FcγRIIIa receptors. Antibody glycan profiles were determined by HPLC. Neither the specificity nor the affinity of the mAbs determined the potency of Fc-effector function. FcγRIIIa binding strongly predicted ADCC and decreased galactose content inversely correlated with ADCP, whereas N-glycolylneuraminic acid-containing structures exhibited enhanced ADCP. Additionally, the bi-antenary glycan arm onto which galactose was added predicted enhanced binding to FcγRIIIa and ADCC activity, independent of the specificity of the mAb. Our studies point to the specific Fc-glycan structures that can selectively promote Fc-effector functions independently of the antibody specificity. Furthermore, we demonstrated antibody glycan structures associated with enhanced ADCP activity, an emerging Fc-effector function that may aid in the control and clearance of HIV infection.

Amplification of epidermal growth factor receptor gene in renal cell carcinoma

DEFF Research Database (Denmark)

El-Hariry, Iman; Powles, Thomas; Lau, Mike R

2010-01-01

Expression of epidermal growth factor receptor (EGFR) may be of prognostic value in renal cell cancer (RCC). Gene amplification of EGFR was investigated in a cohort of 315 patients with advanced RCC from a previously reported randomised study. Using fluorescent in situ hybridisation, only 2...

Production and characterization of monoclonal antibodies against rat platelet GPIIb/IIIa

International Nuclear Information System (INIS)

Miyazaki, H.; Tamura, S.; Sudo, T.; Suzuki, T.

1990-01-01

Four murine monoclonal antibodies against rat platelets were produced by fusion of spleen cells from mice intravenously immunized with whole rat platelets. All four antibodies immunoprecipitated two major platelet membrane proteins with apparent molecular weights of 130,000 and 82,000 (nonreduced) and of 120,000 and 98,000 (reduced), which were structurally analogous to human glycoprotein (GP) IIb/IIIa, i.e. rat GPIIb/IIIa. Two of four antibodies, named P9 and P55, strongly inhibited adenosine diphosphate (ADP)-induced aggregation of washed rat platelets and caused approximately 50% inhibition of human fibrinogen binding to ADP-stimulated rat platelets, suggesting that rat GPIIb/IIIa serves as a fibrinogen receptor in ADP-induced aggregation. In contrast, two other antibodies, named P14 and P34, themselves caused aggregation of rat platelets in platelet-rich plasma (PRP) and the secretion of 14C-serotonin from 14C-serotonin-labeled PRP. These results indicate that rat GPIIb/IIIa plays an important role in platelet aggregation

Two-site sandwich radioimmunoassay of human gamma interferon with monoclonal antibodies

Energy Technology Data Exchange (ETDEWEB)

Tanaka, E; Imai, M; Usuda, S; Tachibana, K; Okamoto, H; Ohike, Y; Nakamura, T; Miyakawa, Y; Mayumi, M [Jichi Medical School, Minamikawachi, Tochigi (Japan)

1985-03-18

Two monoclonal antibodies were raised against human gamma interferon (IFN-..gamma..) derived from E. coli harboring the recombinant cDNA for IFN-..gamma.., and one against a synthetic peptide representing its C-terminus amino acid sequence of 20 residues. The monoclonal antibody against the synthetic peptide reacted either with IFN-..gamma.. or the synthetic peptide. One monoclonal anti-IFN-..gamma.. did not react with the synthetic peptide, while the other showed a weak binding with the peptide. A 2-site '1-step' radioimmunoassay was developed. The assay was rapid with a sensitivity capable of detecting a few ng/ml of IFN-..gamma...

Binding characteristics of brain-derived neurotrophic factor to its receptors on neurons from the chick embryo

Energy Technology Data Exchange (ETDEWEB)

Rodriguez-Tebar, A.; Barde, Y.A.

1988-09-01

Brain-derived neurotrophic factor (BDNF), a protein known to support the survival of embryonic sensory neurons and retinal ganglion cells, was derivatized with 125I-Bolton-Hunter reagent and obtained in a biologically active, radioactive form (125I-BDNF). Using dorsal root ganglion neurons from chick embryos at 9 d of development, the basic physicochemical parameters of the binding of 125I-BDNF with its receptors were established. Two different classes of receptors were found, with dissociation constants of 1.7 x 10(-11) M (high-affinity receptors) and 1.3 x 10(-9) M (low-affinity receptors). Unlabeled BDNF competed with 125I-BDNF for binding to the high-affinity receptors with an inhibition constant essentially identical to the dissociation constant of the labeled protein: 1.2 x 10(-11) M. The association and dissociation rates from both types of receptors were also determined, and the dissociation constants calculated from these kinetic experiments were found to correspond to the results obtained from steady-state binding. The number of high-affinity receptors (a few hundred per cell soma) was 15 times lower than that of low-affinity receptors. No high-affinity receptors were found on sympathetic neurons, known not to respond to BDNF, although specific binding of 125I-BDNF to these cells was detected at a high concentration of the radioligand. These results are discussed and compared with those obtained with nerve growth factor on the same neuronal populations.

Binding characteristics of brain-derived neurotrophic factor to its receptors on neurons from the chick embryo

International Nuclear Information System (INIS)

Rodriguez-Tebar, A.; Barde, Y.A.

1988-01-01

Brain-derived neurotrophic factor (BDNF), a protein known to support the survival of embryonic sensory neurons and retinal ganglion cells, was derivatized with 125I-Bolton-Hunter reagent and obtained in a biologically active, radioactive form (125I-BDNF). Using dorsal root ganglion neurons from chick embryos at 9 d of development, the basic physicochemical parameters of the binding of 125I-BDNF with its receptors were established. Two different classes of receptors were found, with dissociation constants of 1.7 x 10(-11) M (high-affinity receptors) and 1.3 x 10(-9) M (low-affinity receptors). Unlabeled BDNF competed with 125I-BDNF for binding to the high-affinity receptors with an inhibition constant essentially identical to the dissociation constant of the labeled protein: 1.2 x 10(-11) M. The association and dissociation rates from both types of receptors were also determined, and the dissociation constants calculated from these kinetic experiments were found to correspond to the results obtained from steady-state binding. The number of high-affinity receptors (a few hundred per cell soma) was 15 times lower than that of low-affinity receptors. No high-affinity receptors were found on sympathetic neurons, known not to respond to BDNF, although specific binding of 125I-BDNF to these cells was detected at a high concentration of the radioligand. These results are discussed and compared with those obtained with nerve growth factor on the same neuronal populations

Epidermal growth factor and its receptors in human pancreatic carcinoma

International Nuclear Information System (INIS)

Chen, Y.F.; Pan, G.Z.; Hou, X.; Liu, T.H.; Chen, J.; Yanaihara, C.; Yanaihara, N.

1990-01-01

The role of epidermal growth factor (EGF) in oncogenesis and progression of malignant tumors is a subject of vast interest. In this study, radioimmunoassay and radioreceptor assay of EGF were established. EGF contents in malignant and benign pancreatic tumors, in normal pancreas tissue, and in culture media of a human pancreatic carcinoma cell line were determined. EGF receptor binding studies were performed. It was shown that EGF contents in pancreatic carcinomas were significantly higher than those in normal pancreas or benign pancreatic tumors. EGF was also detected in the culture medium of a pancreatic carcinoma cell line. The binding of 125I-EGF to the pancreatic carcinoma cells was time and temperature dependent, reversible, competitive, and specific. Scatchard analysis showed that the dissociation constant of EGF receptor was 2.1 X 10(-9) M, number of binding sites was 1.3 X 10(5) cell. These results indicate that there is an over-expression of EGF/EGF receptors in pancreatic carcinomas, and that an autocrine regulatory mechanism may exist in the growth-promoting effect of EGF on tumor cells

Role of polymorphic Fc receptor Fc gammaRIIa in cytokine release and adverse effects of murine IgG1 anti-CD3/T cell receptor antibody (WT31).

Science.gov (United States)

Tax, W J; Tamboer, W P; Jacobs, C W; Frenken, L A; Koene, R A

1997-01-15

Anti-CD3 monoclonal antibody (mAb) OKT3 is immunosuppressive, but causes severe adverse effects during the first administration ("first-dose reaction"). These adverse effects are presumably caused by cytokine release that results from T-cell activation. In vitro, T-cell activation by anti-CD3 mAb requires interaction with monocyte Fc receptors. The Fc receptor for murine IgG1, Fc gammaRIIa, is polymorphic. In some individuals, murine IgG1 anti-CD3 mAb causes T-cell proliferation and cytokine release in vitro (high responders [HR]), whereas in individuals with the low-responder (LR) phenotype it does not. We have now investigated the role of this Fc gammaRIIa polymorphism in the release of cytokines in vivo and the occurrence of adverse effects after the administration of WT31, a murine IgG1 anti-CD3/T cell receptor mAb. WT31 caused an increase of plasma tumor necrosis factor-alpha in all four HR patients and none of the five LR patients. In all HR patients except one, plasma gamma-interferon and interleukin 6 also increased, and a first-dose response was observed, whereas no cytokine release or adverse effects occurred in any of the LR patients. WT31 caused lymphopenia in all HR and none of the LR patients. FACS analysis demonstrated that in HR patients, after the initial disappearance of CD3+ cells from peripheral blood, modulation of CD3 occurred, whereas in LR patients a high degree of coating of the lymphocytes was observed. Surprisingly, WT31 also induced a marked granulocytopenia, as well as a decrease of thrombocytes, in three of the four HR patients (and in none of the LR patients). These data provide direct clinical evidence that Fc receptor interaction determines the release of cytokines and the occurrence of adverse effects after administration of anti-CD3/T cell receptor mAb. Furthermore, these data suggest that tumor necrosis factor-alpha by itself is not sufficient to induce the first-dose reaction.

In vitro invasion of small-cell lung cancer cell lines correlates with expression of epidermal growth factor receptor

DEFF Research Database (Denmark)

Damstrup, L; Rude Voldborg, B; Spang-Thomsen, M

1998-01-01

receptor (EGFR) in a panel of 21 small-cell lung cancer (SCLC) cell lines. We have previously reported that ten of these cell lines expressed EGFR protein detected by radioreceptor and affinity labelling assays. In 11 small-cell lung cancer (SCLC) cell lines, EGFR mRNA was detected by Northern blot...... analysis. In vitro invasion in a Boyden chamber assay was found in all EGFR-positive cell lines, whereas no invasion was detected in the EGFR-negative cell lines. Quantification of the in vitro invasion in 12 selected SCLC cell lines demonstrated that, in the EGFR-positive cell lines, between 5% and 16......-PCR). However, in vitro invasive SCLC cell lines could not be distinguished from non-invasive cell lines based on the expression pattern of these molecules. In six SCLC cell lines, in vitro invasion was also determined in the presence of the EGFR-neutralizing monoclonal antibody mAb528. The addition...

Sex-specific hormone receptors in urothelial carcinomas of the human urinary bladder: a comparative analysis of clinicopathological features and survival outcomes according to receptor expression.

Science.gov (United States)

Tuygun, Can; Kankaya, Duygu; Imamoglu, Abdurrahim; Sertcelik, Ayse; Zengin, Kursad; Oktay, Murat; Sertcelik, Nurettin

2011-01-01

To investigate the expression of sex-specific hormone receptors in normal bladder urothelium and urothelial carcinomas (UCs) of the bladder, and to analyze clinicopathological features and survival outcomes according to receptor expression. We evaluated the clinical data and tumor specimens of 139 patients with bladder cancer (BC). In addition, 72 samples of normal urothelium were included. Immunohistochemistry was performed using streptavidin-biotin peroxidase method, a monoclonal androgen receptor (AR), and an estrogen receptor-β (ERβ) antibody on paraffin-embedded tissue sections. Expression levels of each receptor were assessed by evaluating 500 tumor cells for each case and the percentage of positively-stained nuclei was recorded. None of the 58 male control cases showed any AR and ERβ expression. Five (35, 71%) of the 14 female control cases expressed ERβ. Of the 139 patients with UCs, 71 (51, 07%) expressed AR (62 male vs. 9 female; P = 0.413) and 44 (31, 65%) (39 male vs. 5 female; P = 0.402) showed ERβ expression (P receptors alone cannot be responsible for gender differences in BC rates because they were expressed in similar rates in both sexes. Copyright © 2011 Elsevier Inc. All rights reserved.

The diminished expression of proangiogenic growth factors and their receptors in gastric ulcers of cirrhotic patients.

Science.gov (United States)

Luo, Jiing-Chyuan; Peng, Yen-Ling; Hou, Ming-Chih; Huang, Kuang-Wei; Huang, Hui-Chun; Wang, Ying-Wen; Lin, Han-Chieh; Lee, Fa-Yauh; Lu, Ching-Liang

2013-01-01

The pathogenesis of the higher occurrence of peptic ulcer disease in cirrhotic patients is complex. Platelets can stimulate angiogenesis and promote gastric ulcer healing. We compared the expressions of proangiogenic growth factors and their receptors in the gastric ulcer margin between cirrhotic patients with thrombocytopenia and those of non-cirrhotic patients to elucidate possible mechanisms. Eligible cirrhotic patients (n = 55) and non-cirrhotic patients (n = 55) who had gastric ulcers were enrolled. Mucosa from the gastric ulcer margin and non-ulcer areas were sampled and the mRNA expressions of the proangiogenic growth factors (vascular endothelial growth factor [VEGF], platelet derived growth factor [PDGF], basic fibroblast growth factor [bFGF]) and their receptors (VEGFR1, VEGFR2, PDGFRA, PDGFRB, FGFR1, FGFR2) were measured and compared. Platelet count and the expressions of these growth factors and their receptors were correlated with each other. The two groups were comparable in terms of gender, ulcer size and infection rate of Helicobacter pylori. However, the cirrhotic group were younger in age, had a lower platelet count than those in the non-cirrhotic group (pexpressions of PDGFB, VEGFR2, FGFR1, and FGFR2 in gastric ulcer margin when compared with those of the non-cirrhotic patients (pexpressions of PDGFB and VEGFR2, FGFR1, and FGFR2 were well correlated with the degree of thrombocytopenia in these cirrhotic patients (ρ>0.5, pimplied that diminished activity of proangiogenic factors and their receptors may contribute to the pathogenesis of gastric ulcers in cirrhotic patients.

Relationship between hyperthyroidism and monoclonal gammapathy

International Nuclear Information System (INIS)

Canas, Carlos Alberto

2007-01-01

A 66-year-old man with primary hyperparathyroidism (PHPT) and monoclonal gammapathy associated to it of uncertain significance (MGUS). A possible pathogenic relationship between HPTP and MGUS is analyzed. Interleukin 6 could play a pivotal role.

Interactions between Type III receptor tyrosine phosphatases and growth factor receptor tyrosine kinases regulate tracheal tube formation in Drosophila

Directory of Open Access Journals (Sweden)

Mili Jeon

2012-04-01

The respiratory (tracheal system of the Drosophila melanogaster larva is an intricate branched network of air-filled tubes. Its developmental logic is similar in some ways to that of the vertebrate vascular system. We previously described a unique embryonic tracheal tubulogenesis phenotype caused by loss of both of the Type III receptor tyrosine phosphatases (RPTPs, Ptp4E and Ptp10D. In Ptp4E Ptp10D double mutants, the linear tubes in unicellular and terminal tracheal branches are converted into bubble-like cysts that incorporate apical cell surface markers. This tube geometry phenotype is modulated by changes in the activity or expression of the epidermal growth factor receptor (Egfr tyrosine kinase (TK. Ptp10D physically interacts with Egfr. Here we demonstrate that the Ptp4E Ptp10D phenotype is the consequence of the loss of negative regulation by the RPTPs of three growth factor receptor TKs: Egfr, Breathless and Pvr. Reducing the activity of any of the three kinases by tracheal expression of dominant-negative mutants suppresses cyst formation. By competing dominant-negative and constitutively active kinase mutants against each other, we show that the three RTKs have partially interchangeable activities, so that increasing the activity of one kinase can compensate for the effects of reducing the activity of another. This implies that SH2-domain downstream effectors that are required for the phenotype are likely to be able to interact with phosphotyrosine sites on all three receptor TKs. We also show that the phenotype involves increases in signaling through the MAP kinase and Rho GTPase pathways.

PMab-52: Specific and Sensitive Monoclonal Antibody Against Cat Podoplanin for Immunohistochemistry.

Science.gov (United States)

Yamada, Shinji; Itai, Shunsuke; Nakamura, Takuro; Yanaka, Miyuki; Saidoh, Noriko; Chang, Yao-Wen; Handa, Saori; Harada, Hiroyuki; Kagawa, Yumiko; Ichii, Osamu; Konnai, Satoru; Kaneko, Mika K; Kato, Yukinari

2017-10-01

Podoplanin (PDPN) is expressed in several normal tissues, such as lymphatic endothelial cells, podocytes of renal glomerulus, and type I alveolar cells of lung. PDPN activates platelet aggregation by binding to C-type lectin-like receptor-2 (CLEC-2) on platelet. Although monoclonal antibodies (mAbs) against human PDPN, mouse PDPN, rat PDPN, rabbit PDPN, dog PDPN, and bovine PDPN have been established, anticat PDPN (cPDPN) mAbs have not been developed. In this study, we immunized mice with Chinese hamster ovary (CHO)-K1 cell lines expressing cPDPN, and developed anti-cPDPN mAbs. One of the clones, PMab-52 (IgM, kappa), detected cPDPN specifically in flow cytometry and Western blot analysis. PMab-52 is also useful for detecting feline squamous cell carcinoma cells in immunohistochemical analysis. PMab-52 is expected to be useful for investigating the function of cPDPN in feline carcinomas.

A sensitive radioimmunoassay for the detection of monoclonal anti-idiotype antibodies

International Nuclear Information System (INIS)

Morahan, G.

1983-01-01

A radioimmunoassay was developed in order to detect anti-idiotypic antibodies in the supernatants of hybrid cells. This assay is both sensitive and specific for anti-idiotypic (but not anti-allotypic) antibodies. Monoclonal antibodies present in test supernatants are bound by an anti-immunoglobulin coated solid phase. Subsequent incubation with a source of mouse immunoglobulin 'blocks' unreacted anti-immunoglobulin antibodies on the solid phase. Anti-idiotypic antibodies are then detected by their ability to bind 125 I-labelled idiotype-bearing antibody. This paper describes the use of this assay to detect monoclonal anti-idiotypic antibodies in 2 systems; the cross-reactive idiotype of A/J anti-ABA antibodies, and the idiotype expressed by the myeloma protein HOPC 8. Similarly, 125 I-labelled anti-idiotype antibodies may be used in this assay to detect monoclonal idiotype-bearing antibodies. Further modifications are described which would allow the detection of monoclonal anti-allotype antibodies. (Auth.)

Monoclonal antibodies: an overview of their advantages and limitations in nuclear medicine

International Nuclear Information System (INIS)

Revillard, J.P.; Cohen, J.

1982-01-01

The following topics were reviewed: antigen recognition by the immune system; development of immunoassays for antigenic components of biological fluids; monoclonal antibodies against infectious agents; monochonal antibodies against tumor and differentiation antigens; human monoclonal antibodies

Improved radioimaging and tumor localization with monoclonal F(ab')2

International Nuclear Information System (INIS)

Wahl, R.L.; Parker, C.W.; Philpott, G.W.

1983-01-01

Monoclonal anti-tumor antibodies have great promise for radioimmunodetection and localization of tumors. Fab and F(ab')2 fragments, which lack the Fc fragment of antibody (Ab), are cleared more rapidly from the circulation and may have less nonspecific tissue binding than intact Ab. In radioimaging studies using a murine monoclonal antibody to carcinoembryonic antigen in a human colon carcinoma xenografted into hamsters, F(ab')2 fragments were shown superior to Fab fragments and intact antibody for scintiscanning. In double-label experiments with anti-CEA antibody and control monoclonal IgG, F(ab')2 fragments were found to give better and more rapid specific tumor localization than intact antibody or Fab fragments. F(ab')2 fragments offer significant promise for tumor imaging and possibly therapy

Epidermal growth factor receptor inhibition by anti-CD147 therapy in cutaneous squamous cell carcinoma.

Science.gov (United States)

Frederick, John W; Sweeny, Larissa; Hartman, Yolanda; Zhou, Tong; Rosenthal, Eben L

2016-02-01

Advanced cutaneous squamous cell carcinoma (SCC) is an uncommon and aggressive malignancy. As a result, there is limited understanding of its biology and pathogenesis. CD147 and epidermal growth factor receptor (EGFR) have been identified as oncologically important targets, but their relationship remains undefined in cutaneous SCC. Multiple cutaneous SCC cell lines (Colo-16, SRB-1, and SRB-12), were treated in vitro with a range of chimeric anti-CD147 monoclonal antibody (mAb) (0, 50, 100, and 200 µg/mL) or transfected with a small interfering RNA against CD147 (SiCD147). Cell proliferation, migration (scratch wound healing assay), and protein expression was then assessed. In vivo, Colo-16 flank xenografts were treated anti-CD147 mAb (150 µg i.p. triweekly). After treatment with anti-CD147 (200 µg/mL), there was a significant decrease in proliferation for all cell lines relative to controls (p CD147 (200 µg/mL) resulted in decreased cell migration for all cell lines, with an average of 43% reduction in closure compared to controls (p CD147 antibody therapy and siRNA mediated reduction in CD147 expression were both found to decrease protein expression of EGFR, which correlated with a reduction in downstream total and phosphorylated protein kinase B (pAKT). Tumor growth in vivo was reduced for both the anti-CD147 treatment group and the SiCD147 group relative to controls. Inhibition and downregulation of CD147 in cutaneous SCC resulted in suppression of the malignant phenotype in vitro and in vivo, which may be mediated in part by an alteration in EGFR expression. As a result, CD147 may serve as a potential therapeutic target for advanced cutaneous SCC. © 2014 Wiley Periodicals, Inc.

Preparation of monoclonal antibodies against radiation-induced protein

International Nuclear Information System (INIS)

Nozawa, R.; Tanaka, A.; Watanabe, H.; Kitayama, S.

1992-01-01

We obtained the 6 monoclonal antibodies against gamma-induced proteins of Deinococcus radiodurans, and these antibodies were designated as Mab-3F, 4B, 4D, 4F, 4G and 12G. Using these antibodies, we investigated the relations between gamma-induced proteins and other stress protein in strain R1, and the induction of proteins were compared among strain R1, resistant mutant (rec1) and radiosensitive mutant (rec30). We found new 6 proteins recognized by these monoclonal antibodies which were induced after gamma-irradiation especially in strain R1 and rec 1, but not induced in strain rec30. We suppose that these proteins participate in repair of DNA damages including double strand breaks caused by gamma-irradiation. One of them was around 46kDa protein band recognized by Mab-12G, and this protein was so induced in a large quantity after irradiation that the protein could detect by gold staining. In addition to this observation, we found some proteins which were induced in R1 and rec 1 by gamma-irradiation and other stress, but not in strain rec30, such as 31kDa protein band recognized by Mab-3F, 4B and 4G, and other 11 proteins which were especially induced in irradiated strain R1. The latter proteins might be reinforcement factor to radioresistance such as GroE and DnaK, or participant in repair of damage by gamma-irradiation in strain R1. (author)

Prevalence and type of monoclonal gammopathy of undetermined significance in an apparently healthy Nigerian population: a cross sectional study

Directory of Open Access Journals (Sweden)

Onwah A

2012-06-01

Full Text Available Abstract Background The prevalence of monoclonal gammopathy of undetermined significance (MGUS, a premalignant plasma-cell disorder has not been determined in our geographic area Nigeria. Methods A cross sectional survey was carried on apparently healthy Nigerians selected by multistage sampling technique from the cosmopolitan city of Lagos, Nigeria. Subjects enrolled into the study had 2-step screening for the presence, type and concentration of monoclonal band. Agarose-gel electrophoresis was performed on all serum samples, and any serum sample with a discrete band of monoclonal protein or thought to have a localized band was subjected to Immunofixation. Subjects were also evaluated for Bence jones proteinuria, haematological and biochemical parameters. Results Four hundred and ten subjects with a mean age of 45.68 ± 10.3 years, a median of 45.00 years and a range of 20 to 80 years were enrolled into the study. MGUS was identified in only one (0.24 percent of the 410 study subject. This subject was demonstrated to have a double monoclonal gammopathy; IgGλ at 16.9 g/L and IgAκ at 8.5 g/L. None of them including the sole subject with MGUS had a monoclonal urinary light chain. Conclusion Among residents of Lagos, Nigeria, MGUS was found in only 0.24% percent of apparently normal persons with a median age of 45 years. This suggests that MGUS which represents the earliest stage of monoclonal plasma/lymphoid cell proliferation is not a common finding in the relatively young population of Nigeria. Future epidemiologic studies dealing with plasma cell disorders in older people are required to carefully examine the relationship between environmental factors and prevalence of MGUS and its ultimate progression to MM.

Design and Synthesis of Benzimidazoles As Novel Corticotropin-Releasing Factor 1 Receptor Antagonists.

Science.gov (United States)

Mochizuki, Michiyo; Kori, Masakuni; Kobayashi, Katsumi; Yano, Takahiko; Sako, Yuu; Tanaka, Maiko; Kanzaki, Naoyuki; Gyorkos, Albert C; Corrette, Christopher P; Cho, Suk Young; Pratt, Scott A; Aso, Kazuyoshi

2016-03-24

Benzazole derivatives with a flexible aryl group bonded through a one-atom linker as a new scaffold for a corticotropin-releasing factor 1 (CRF1) receptor antagonist were designed, synthesized, and evaluated. We expected that structural diversity could be expanded beyond that of reported CRF1 receptor antagonists. In a structure-activity relationship study, 4-chloro-N(2)-(4-chloro-2-methoxy-6-methylphenyl)-1-methyl-N(7),N(7)-dipropyl-1H-benzimidazole-2,7-diamine 29g had the most potent binding activity against a human CRF1 receptor and the antagonistic activity (IC50 = 9.5 and 88 nM, respectively) without concerns regarding cytotoxicity at 30 μM. Potent CRF1 receptor-binding activity in brain in an ex vivo test and suppression of stress-induced activation of the hypothalamus-pituitary-adrenocortical (HPA) axis were also observed at 138 μmol/kg of compound 29g after oral administration in mice. Thus, the newly designed benzimidazole 29g showed in vivo CRF1 receptor antagonistic activity and good brain penetration, indicating that it is a promising lead for CRF1 receptor antagonist drug discovery research.

Targeting the epidermal growth factor receptor in non-small cell lung cancer cells: the effect of combining RNA interference with tyrosine kinase inhibitors or cetuximab

Directory of Open Access Journals (Sweden)

Chen Gang

2012-03-01

Full Text Available Abstract Background The epidermal growth factor receptor (EGFR is a validated therapeutic target in non-small cell lung cancer (NSCLC. However, current single agent receptor targeting does not achieve a maximal therapeutic effect, and some mutations confer resistance to current available agents. In the current study we have examined, in different NSCLC cell lines, the combined effect of RNA interference targeting the EGFR mRNA, and inactivation of EGFR signaling using different receptor tyrosine kinase inhibitors (TKIs or a monoclonal antibody cetuximab. Methods NSCLC cells (cell lines HCC827, H292, H358, H1650, and H1975 were transfected with EGFR siRNA and/or treated with the TKIs gefitinib, erlotinib, and afatinib, and/or with the monoclonal antibody cetuximab. The reduction of EGFR mRNA expression was measured by real-time quantitative RT-PCR. The down-regulation of EGFR protein expression was measured by western blot, and the proliferation, viability, caspase3/7 activity, and apoptotic morphology were monitored by spectrophotometry, fluorimetry, and fluorescence microscopy. The combined effect of EGFR siRNA and different drugs was evaluated using a combination index. Results EGFR-specific siRNA strongly inhibited EGFR protein expression almost equally in all cell lines and inhibited cell growth and induced cell apoptosis in all NSCLC cell lines studied, albeit with a different magnitude. The effects on growth obtained with siRNA was strikingly different from the effects obtained with TKIs. The effects of siRNA probably correlate with the overall oncogenic significance of the receptor, which is only partly inhibited by the TKIs. The cells which showed weak response to TKIs, such as the H1975 cell line containing the T790M resistance mutation, were found to be responsive to siRNA knockdown of EGFR, as were cell lines with downstream TKI resistance mutations. The cell line HCC827, harboring an exon 19 deletion mutation, was more than 10-fold

Role of tissue factor and protease-activated receptors in a mouse model of endotoxemia.

Science.gov (United States)

Pawlinski, Rafal; Pedersen, Brian; Schabbauer, Gernot; Tencati, Michael; Holscher, Todd; Boisvert, William; Andrade-Gordon, Patricia; Frank, Rolf Dario; Mackman, Nigel

2004-02-15

Sepsis is associated with a systemic activation of coagulation and an excessive inflammatory response. Anticoagulants have been shown to inhibit both coagulation and inflammation in sepsis. In this study, we used both genetic and pharmacologic approaches to analyze the role of tissue factor and protease-activated receptors in coagulation and inflammation in a mouse endotoxemia model. We used mice expressing low levels of the procoagulant molecule, tissue factor (TF), to analyze the effects of TF deficiency either in all tissues or selectively in hematopoietic cells. Low TF mice had reduced coagulation, inflammation, and mortality compared with control mice. Similarly, a deficiency of TF expression by hematopoietic cells reduced lipopolysaccharide (LPS)-induced coagulation, inflammation, and mortality. Inhibition of the down-stream coagulation protease, thrombin, reduced fibrin deposition and prolonged survival without affecting inflammation. Deficiency of either protease activated receptor-1 (PAR-1) or protease activated receptor-2 (PAR-2) alone did not affect inflammation or survival. However, a combination of thrombin inhibition and PAR-2 deficiency reduced inflammation and mortality. These data demonstrate that hematopoietic cells are the major pathologic site of TF expression during endotoxemia and suggest that multiple protease-activated receptors mediate crosstalk between coagulation and inflammation.

Complement-mediated bactericidal activity of anti-factor H binding protein monoclonal antibodies against the meningococcus relies upon blocking factor H binding.

Science.gov (United States)

Giuntini, Serena; Reason, Donald C; Granoff, Dan M

2011-09-01

Binding of the complement-downregulating protein factor H (fH) to the surface of the meningococcus is important for survival of the organism in human serum. The meningococcal vaccine candidate factor H binding protein (fHbp) is an important ligand for human fH. While some fHbp-specific monoclonal antibodies (MAbs) block binding of fH to fHbp, the stoichiometry of blocking in the presence of high serum concentrations of fH and its effect on complement-mediated bactericidal activity are unknown. To investigate this question, we constructed chimeric antibodies in which the human IgG1 constant region was paired with three murine fHbp-specific binding domains designated JAR 3, JAR 5, and MAb502. By surface plasmon resonance, the association rates for binding of all three MAbs to immobilized fHbp were >50-fold higher than that for binding of fH to fHbp, and the MAb dissociation rates were >500-fold lower than that for fH. While all three MAbs elicited similar C1q-dependent C4b deposition on live bacteria (classical complement pathway), only those antibodies that inhibited binding of fH to fHbp (JAR 3 and JAR 5) had bactericidal activity with human complement. MAb502, which did not inhibit fH binding, had complement-mediated bactericidal activity only when tested with fH-depleted human complement. When an IgG1 anti-fHbp MAb binds to sparsely exposed fHbp on the bacterial surface, there appears to be insufficient complement activation for bacteriolysis unless fH binding also is inhibited. The ability of fHbp vaccines to elicit protective antibodies, therefore, is likely to be enhanced if the antibody repertoire is of high avidity and includes fH-blocking activity.

Epitope Mapping of Monoclonal Antibody PMab-52 Against Cat Podoplanin.

Science.gov (United States)

Chang, Yao-Wen; Kaneko, Mika K; Yamada, Shinji; Kato, Yukinari

2018-02-02

The mucin-type membrane glycoprotein podoplanin (PDPN) is frequently overexpressed in numerous malignant cancers, including squamous cell carcinoma, germinal neoplasia, mesothelioma, lung cancer, oral cancer, and brain tumor. PDPN expression is strongly associated with cancer progression and poor prognosis. Furthermore, PDPN binds to C-type lectin-like receptor 2 (CLEC-2) on platelets, followed by PDPN-mediated platelet aggregation to facilitate tumor metastasis. We have previously reported a novel anti-cat PDPN (cPDPN) monoclonal antibody (mAb), PMab-52, which specifically detects cPDPN using flow cytometry analysis and successfully identifies cPDPN in feline squamous cell carcinomas. However, the specific binding epitope of cPDPN for PMab-52 remains unelucidated. In this study, a series of deletion or point mutants of cPDPN were utilized for investigating the binding epitopes of PMab-52 using flow cytometry and Western blotting. The findings of this study revealed that the critical epitopes of platelet aggregation-stimulating domain 4 (PLAG4) of cPDPN are responsible for the binding of PMab-52 to cPDPN.

Foreign or Domestic CARs: Receptor Ligands as Antigen-Binding Domains

Directory of Open Access Journals (Sweden)

Donald R. Shaffer

2014-01-01

Full Text Available Chimeric antigen receptors (CARs are increasingly being used in clinical trials to treat a variety of malignant conditions and recent results with CD19-specific CARs showing complete tumor regressions has sparked the interest of researchers and the public alike. Traditional CARs have been generated using single-chain variable fragments (scFv, often derived from murine monoclonal antibodies, for antigen specificity. As the clinical experience with CAR T cells grows, so does the potential for unwanted immune responses against the foreign transgene. Strategies that may reduce the immunogenicity of CAR T cells are humanization of the scFv and the use of naturally occurring receptor ligands as antigen-binding domains. Herein, we review the experience with alternatively designed CARs that contain receptor ligands rather than scFv. While most of the experiences have been in the pre-clinical setting, clinical data is also emerging.

Biochemical and immunological studies of the Muscarinic acetylcholine receptor

International Nuclear Information System (INIS)

Gainer, M.W.

1985-01-01

Muscarinic acetylcholine receptors were solubilized from bovine brain membranes with 3[3-cholamidopropyl)dimethylammonio]propanesulfonate (CHAPS). A combination of 10 mM CHAPS and 1 M NaCl solubilized 15-40% of the specific receptor binding sites from these membranes. The solubilized receptors displayed high affinity binding of the muscarinic antagonist, [ 3 H]quinuclidinyl benzilate with a K/sub D/ = 300 pM. In addition, the solubilized and retained guanyl nucleotide regulation of agonist binding characteristic of membrane bound receptors. Gel filtration experiments showed that solubilized receptors from cortex and cerebellum had different elution profiles. Analysis by sucrose density gradient centrifugation showed that receptors in the lower molecular weight peak sedimented with a coefficient of 5S. Receptors in the larger molecular weight peak sedimented to the bottom of the gradient. Attempts to purify receptors by chromatography on propylbenzilycholine Sepharose were unsuccessful. The technique used to attach the ligand to the solid support, however, was used to synthesize a PrBCM-BSA conjugate and the conjugate used as an antigen in the production of anti-ligand antibodies. Two anti-PrBCM monoclonal antibodies were isolated that recognize muscarinic but not nicotinic cholinergic ligands. The abilities of the antibodies to recognize other muscarinic ligands indicated the antibodies recognized a portion of PrBCM involved in binding to the receptor. Construction of an antibody affinity resin resulted in the purification of this fragment a minimum of 170 fold

Expression of the epidermal growth factor receptor in human small cell lung cancer cell lines

DEFF Research Database (Denmark)

Damstrup, L; Rygaard, K; Spang-Thomsen, M

1992-01-01

of EGF receptor mRNA in all 10 cell lines that were found to be EGF receptor-positive and in one cell line that was found to be EGF receptor-negative in the radioreceptor assay and affinity labeling. Our results provide, for the first time, evidence that a large proportion of a broad panel of small cell......Epidermal growth factor (EGF) receptor expression was evaluated in a panel of 21 small cell lung cancer cell lines with radioreceptor assay, affinity labeling, and Northern blotting. We found high-affinity receptors to be expressed in 10 cell lines. Scatchard analysis of the binding data...... demonstrated that the cells bound between 3 and 52 fmol/mg protein with a KD ranging from 0.5 x 10(-10) to 2.7 x 10(-10) M. EGF binding to the receptor was confirmed by affinity-labeling EGF to the EGF receptor. The cross-linked complex had a M(r) of 170,000-180,000. Northern blotting showed the expression...

ATAR, a novel tumor necrosis factor receptor family member, signals through TRAF2 and TRAF5.

Science.gov (United States)

Hsu, H; Solovyev, I; Colombero, A; Elliott, R; Kelley, M; Boyle, W J

1997-05-23

Members of tumor necrosis factor receptor (TNFR) family signal largely through interactions with death domain proteins and TRAF proteins. Here we report the identification of a novel TNFR family member ATAR. Human and mouse ATAR contain 283 and 276 amino acids, respectively, making them the shortest known members of the TNFR superfamily. The receptor is expressed mainly in spleen, thymus, bone marrow, lung, and small intestine. The intracellular domains of human and mouse ATAR share only 25% identity, yet both interact with TRAF5 and TRAF2. This TRAF interaction domain resides at the C-terminal 20 amino acids. Like most other TRAF-interacting receptors, overexpression of ATAR activates the transcription factor NF-kappaB. Co-expression of ATAR with TRAF5, but not TRAF2, results in synergistic activation of NF-kappaB, suggesting potentially different roles for TRAF2 and TRAF5 in post-receptor signaling.

Monoclonal Antibody Therapy for Advanced Neuroblastoma

Science.gov (United States)

NCI is sponsoring two clinical trials of a monoclonal antibody called ch14.18, in combination with other drugs, to see if the antibody may be helpful for children or young adults (up to age 21) with relapsed or refractory neuroblastoma.

A rapid one-step radiometric assay for hepatitis B surface antigen utilising monoclonal antibodies

International Nuclear Information System (INIS)

Goodall, A.H.; Meek, F.L.; Waters, J.A.; Miescher, G.C.; Janossy, G.; Thomas, H.C.

1982-01-01

A two-site antigen assay for HBsAg has been developed that employs 3 monoclonal antibodies. The antibodies were selected for their high affinity and their particular epitope specificity to establish an assay with a sensitivity for the antigen comparable with that of a conventional assay with heterologous antisera. In addition, by selecting a monoclonal antibody for use as a tracer which does not compete for antigenic binding sites with the solid-phase monoclonal antibodies, it has been possible to perform a two-site assay in a single 1 h incubation step, achieving the same degree of sensitivity. This principle of using monoclonal antibodies in a one-step assay therefore gives advantages of speed and simplicity over assays using heterologous antisera and would be applicable to a variety of antigen assays for which appropriate monoclonal antibodies are available. (Auth.)

Insulin-like growth factor II: complexity of biosynthesis and receptor binding

DEFF Research Database (Denmark)

Gammeltoft, S; Christiansen, Jan; Nielsen, F C

1991-01-01

Insulin-like growth factor II (IGF-II) belongs to the insulin family of peptides and acts as a growth factor in many fetal tissues and tumors. The gene expression of IGF-II is initiated at three different promoters which gives rise to multiple transcripts. In a human rhabdomyosarcoma cell line......, Man-6-P induces cellular responses. We have studied rat brain neuronal precursor cells where Man-6-P acted as a mitogen suggesting that phosphomannosylated proteins may act as growth factors via the Man-6-P/IGF-II receptor. In conclusion, the gene expression and mechanism of action of IGF-II is very...

Molecular characterization of the haptoglobin.hemoglobin receptor CD163. Ligand binding properties of the scavenger receptor cysteine-rich domain region

DEFF Research Database (Denmark)

Madsen, Mette; Møller, Holger J; Nielsen, Marianne Jensby

2004-01-01

CD163 is the macrophage receptor for endocytosis of haptoglobin.hemoglobin complexes. The extracellular region consisting of nine scavenger receptor cysteine rich (SRCR) domains also circulates in plasma as a soluble protein. By ligand binding analysis of a broad spectrum of soluble CD163...... truncation variants, the amino-terminal third of the SRCR region was shown to be crucial for the binding of haptoglobin.hemoglobin complexes. By Western blotting of the CD163 variants, a panel of ten monoclonal antibodies was mapped to SRCR domains 1, 3, 4, 6, 7, and 9, respectively. Only the two antibodies...... to CD163 demonstrated that optimal ligand binding requires physiological plasma calcium concentrations, and an immediate ligand release occurs at the low calcium concentrations measured in acidifying endosomes. In conclusion, SRCR domain 3 of CD163 is an exposed domain and a critical determinant...

Orphan nuclear receptor TR4 and fibroblast growth factor 1 in metabolism

NARCIS (Netherlands)

Liu, Weilin

2016-01-01

Metabolic homeostasis is achieved, in part, through the coordinated activities of members of the Nuclear Receptor (NR) family, a superfamily of ligand-modulated transcription factors (TFs) that mediate responses to a wide range of lipophilic signaling molecules including lipids, steroids, retinoids,

Insulin-like growth factor-II receptors in cultured rat hepatocytes: regulation by cell density

International Nuclear Information System (INIS)

Scott, C.D.; Baxter, R.C.

1987-01-01

Insulin-like growth factor-II (IGF-II) receptors in primary cultures of adult rat hepatocytes were characterized and their regulation by cell density examined. In hepatocytes cultured at 5 X 10(5) cells per 3.8 cm2 plate [ 125 I]IGF-II bound to specific, high affinity receptors (Ka = 4.4 +/- 0.5 X 10(9) l/mol). Less than 1% cross-reactivity by IGF-I and no cross-reactivity by insulin were observed. IGF-II binding increased when cells were permeabilized with 0.01% digitonin, suggesting the presence of an intracellular receptor pool. Determined by Scatchard analysis and by polyacrylamide gel electrophoresis after affinity labeling, the higher binding was due solely to an increase in binding sites present on 220 kDa type II IGF receptors. In hepatocytes cultured at low densities, the number of cell surface receptors increased markedly, from 10-20,000 receptors per cell at a culture density of 6 X 10(5) cells/well to 70-80,000 receptors per cell at 0.38 X 10(5) cells/well. The increase was not due simply to the exposure of receptors from the intracellular pool, as a density-related increase in receptors was also seen in cells permeabilized with digitonin. There was no evidence that IGF binding proteins, either secreted by hepatocytes or present in fetal calf serum, had any effect on the measurement of receptor concentration or affinity. We conclude that rat hepatocytes in primary culture contain specific IGF-II receptors and that both cell surface and intracellular receptors are regulated by cell density

An intelligent identification algorithm for the monoclonal picking instrument

Science.gov (United States)

Yan, Hua; Zhang, Rongfu; Yuan, Xujun; Wang, Qun

2017-11-01

The traditional colony selection is mainly operated by manual mode, which takes on low efficiency and strong subjectivity. Therefore, it is important to develop an automatic monoclonal-picking instrument. The critical stage of the automatic monoclonal-picking and intelligent optimal selection is intelligent identification algorithm. An auto-screening algorithm based on Support Vector Machine (SVM) is proposed in this paper, which uses the supervised learning method, which combined with the colony morphological characteristics to classify the colony accurately. Furthermore, through the basic morphological features of the colony, system can figure out a series of morphological parameters step by step. Through the establishment of maximal margin classifier, and based on the analysis of the growth trend of the colony, the selection of the monoclonal colony was carried out. The experimental results showed that the auto-screening algorithm could screen out the regular colony from the other, which meets the requirement of various parameters.

Epidermal Growth Factor Receptor (EGFR) Crosstalks in Liver Cancer

International Nuclear Information System (INIS)

Berasain, Carmen; Latasa, María Ujue; Urtasun, Raquel; Goñi, Saioa; Elizalde, María; Garcia-Irigoyen, Oihane; Azcona, María; Prieto, Jesús; Ávila, Matías A.

2011-01-01

Hepatocarcinogenesis is a complex multistep process in which many different molecular pathways have been implicated. Hepatocellular carcinoma (HCC) is refractory to conventional chemotherapeutic agents, and the new targeted therapies are meeting with limited success. Interreceptor crosstalk and the positive feedback between different signaling systems are emerging as mechanisms of targeted therapy resistance. The identification of such interactions is therefore of particular relevance to improve therapeutic efficacy. Among the different signaling pathways activated in hepatocarcinogenesis the epidermal growth factor receptor (EGFR) system plays a prominent role, being recognized as a “signaling hub” where different extracellular growth and survival signals converge. EGFR can be transactivated in response to multiple heterologous ligands through the physical interaction with multiple receptors, the activity of intracellular kinases or the shedding of EGFR-ligands. In this article we review the crosstalk between the EGFR and other signaling pathways that could be relevant to liver cancer development and treatment

Dissociation of alloantigen recognition from self major histocompatibility complex-restricted recognition of cytolytic T lymphocytes by monoclonal antireceptor antibodies

International Nuclear Information System (INIS)

Kanagawa, O.; Nagasawa, R.

1987-01-01

Two monoclonal antibodies (mAb) directed to the dual reactive cytolytic T lymphocyte clone OH8 (D/sup b/T H-Y and H-2/sup d/) were established. Analysis by cell surface staining and immunoprecipitation of radiolabeled surface molecules of OH8 followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis reveled that both mAb recognized an identical heterodimeric, clonotypic structure on OH8 cells, i.e., T cell receptor. However, although the MR3-2 mAb inhibited the lysis of either D/sup b/ + H-Y or H-2/sup d/ targets by OH8, the MR3-6 mAb inhibited the lysis of H-2/sup d/ target cells, but not that of D/sup b/ + H-Y target cells. Modulation of T cell receptor by either MR3-2 or MR3-6 mAb rendered the OH8 cytolytic T lyrphocyte incapable of killing both D/sup b/ + H-Y and H-2/sup d/ target cells. These finding suggest that different epitopes of OH8 T cell receptor were involved for the recognition of self + antigen and alloantigen

Interleukin-6-receptor polymorphisms rs12083537, rs2228145, and rs4329505 as predictors of response to tocilizumab in rheumatoid arthritis

DEFF Research Database (Denmark)

Enevold, Christian; Baslund, Bo; Linde, Louise

2014-01-01

Tocilizumab (TCZ), a monoclonal antibody targeting the human interleukin-6-receptor (IL-6R), is indicated for the treatment of rheumatoid arthritis (RA). We examined whether three IL6R single-nucleotide polymorphisms rs12083537, rs2228145 (formerly rs8192284), and rs4329505 with previously report...

Improving food and agricultural production. Thailand. Application on monoclonal antibodies for progesterone measurement

International Nuclear Information System (INIS)

Butcher, G.W.

1991-01-01

The duties of the mission were to provide instructions on the maintenance of hybridoma cell lines and their culture and the harvesting of monoclonal antibodies; to assist the counterparts in Thailand to develop work plans for the use of monoclonal antibodies in radioimmunoassay measurements of progesterone; and to assess the need for and feasibility of establishing a laboratory for producing monoclonal antibodies directed against progesterone. The report contains a summary of the activities performed in fulfillment of these duties

Epitope Dampening Monotypic Measles Virus Hemagglutinin Glycoprotein Results in Resistance to Cocktail of Monoclonal Antibodies

Science.gov (United States)

Lech, Patrycja J.; Tobin, Gregory J.; Bushnell, Ruth; Gutschenritter, Emily; Pham, Linh D.; Nace, Rebecca; Verhoeyen, Els; Cosset, François-Loïc; Muller, Claude P.; Russell, Stephen J.; Nara, Peter L.

2013-01-01

The measles virus (MV) is serologically monotypic. Life-long immunity is conferred by a single attack of measles or following vaccination with the MV vaccine. This is contrary to viruses such as influenza, which readily develop resistance to the immune system and recur. A better understanding of factors that restrain MV to one serotype may allow us to predict if MV will remain monotypic in the future and influence the design of novel MV vaccines and therapeutics. MV hemagglutinin (H) glycoprotein, binds to cellular receptors and subsequently triggers the fusion (F) glycoprotein to fuse the virus into the cell. H is also the major target for neutralizing antibodies. To explore if MV remains monotypic due to a lack of plasticity of the H glycoprotein, we used the technology of Immune Dampening to generate viruses with rationally designed N-linked glycosylation sites and mutations in different epitopes and screened for viruses that escaped monoclonal antibodies (mAbs). We then combined rationally designed mutations with naturally selected mutations to generate a virus resistant to a cocktail of neutralizing mAbs targeting four different epitopes simultaneously. Two epitopes were protected by engineered N-linked glycosylations and two epitopes acquired escape mutations via two consecutive rounds of artificial selection in the presence of mAbs. Three of these epitopes were targeted by mAbs known to interfere with receptor binding. Results demonstrate that, within the epitopes analyzed, H can tolerate mutations in different residues and additional N-linked glycosylations to escape mAbs. Understanding the degree of change that H can tolerate is important as we follow its evolution in a host whose immunity is vaccine induced by genotype A strains instead of multiple genetically distinct wild-type MVs. PMID:23300970

[Production of monoclonal antibodies against a wild strain of rabies virus].

Science.gov (United States)

Akacem, O; Benmansour, A; Coulon, P; Brahimi, M; Benhassine, M

1992-01-01

Production of monoclonal antibodies against a wild strain of rabies virus. Cell fusion of SP 2/O, a murine myeloma against a wild strain of rabies virus has originated five monoclonal antibodies (M.A.) specific for virus nucleocapsid , one M.A. specific for virus glycoprotein and one M.A. specific for a viral membrane protein.

The classification of Sejroe group serovars of Leptospira interrogans with monoclonal antibodies

NARCIS (Netherlands)

Terpstra, W. J.; Korver, H.; van Leeuwen, J.; Klatser, P. R.; Kolk, A. H.

1985-01-01

Using the hybridoma technique we produced monoclonal antibodies to serovars of Leptospira interrogans. We focussed on serovar hardjo which is an important pathogen for humans and animals, and on other serovars of the Sejroe group. With combinations of monoclonals, characteristic patterns of

Insulin-like growth factor-II (IGF II) receptor from rat brain is of lower apparent molecular weight than the IGF II receptor from rat liver

International Nuclear Information System (INIS)

McElduff, A.; Poronnik, P.; Baxter, R.C.

1987-01-01

The binding subunits of the insulin and insulin-like growth factor-I (IGF I) receptors from rat brain are of lower molecular weight than the corresponding receptor in rat liver, possibly due to variations in sialic acid content. We have compared the IGF II receptor from rat brain and rat liver. The brain receptor is of smaller apparent mol wt (about 10 K) on sodium dodecyl sulfate polyacrylamide gel electrophoresis. This size difference is independent of ligand binding as it persists in iodinated and specifically immunoprecipitated receptors. From studies of wheat germ agglutinin binding and the effect of neuraminidase on receptor mobility, we conclude that this difference is not simply due to variations in sialic acid content. Treatment with endoglycosidase F results in reduction in the molecular size of both liver and brain receptors and after this treatment the aglycoreceptors are of similar size. We conclude that in rat brain tissue the IGF II receptor like the binding subunits of the insulin and IGF I receptors is of lower molecular size than the corresponding receptors in rat liver. This difference is due to differences in N-linked glycosylation

Customizing monoclonal antibodies for the treatment of methamphetamine abuse: current and future applications.

Science.gov (United States)

Peterson, Eric C; Gentry, W Brooks; Owens, S Michael

2014-01-01

Monoclonal antibody-based medications designed to bind (+)-methamphetamine (METH) with high affinity are among the newest approaches to the treatment of METH abuse and the associated medical complications. The potential clinical indications for these medications include treatment of overdose, reduction of drug dependence, and protection of vulnerable populations from METH-related complications. Research designed to discover and conduct preclinical and clinical testing of these antibodies suggests a scientific vision for how intact monoclonal antibody (mAb) (singular and plural) or small antigen-binding fragments of mAb could be engineered to optimize the proteins for specific therapeutic applications. In this review, we discuss keys to success in this development process including choosing predictors of specificity, efficacy, duration of action, and safety of the medications in disease models of acute and chronic drug abuse. We consider important aspects of METH-like hapten design and how hapten structural features influence specificity and affinity, with an example of a high-resolution X-ray crystal structure of a high-affinity antibody to demonstrate this structural relationship. Additionally, several prototype anti-METH mAb forms such as antigen-binding fragments and single-chain variable fragments are under development. Unique, customizable aspects of these fragments are presented with specific possible clinical indications. Finally, we discuss clinical trial progress of the first in kind anti-METH mAb, for which METH is the disease target instead of vulnerable central nervous system networks of receptors, binding sites, and neuronal connections. © 2014 Elsevier Inc. All rights reserved.

Isolation and functional effects of monoclonal antibodies binding to thymidylate synthase.

Science.gov (United States)

Jastreboff, M M; Todd, M B; Malech, H L; Bertino, J R

1985-01-29

Monoclonal antibodies against electrophoretically pure thymidylate synthase from HeLa cells have been produced. Antibodies (M-TS-4 and M-TS-9) from hybridoma clones were shown by enzyme-linked immunoassay to recognize thymidylate synthase from a variety of human cell lines, but they did not bind to thymidylate synthase from mouse cell lines. The strongest binding of antibodies was observed to enzyme from HeLa cells. These two monoclonal antibodies bind simultaneously to different antigenic sites on thymidylate synthase purified from HeLa cells, as reflected by a high additivity index and results of cross-linked radioimmunoassay. Both monoclonal antibodies inhibit the activity of thymidylate synthase from human cell lines. The strongest inhibition was observed with thymidylate synthase from HeLa cells. Monoclonal antibody M-TS-9 (IgM subclass) decreased the rate of binding of [3H]FdUMP to thymidylate synthase in the presence of 5,10-methylenetetrahydrofolate while M-TS-4 (IgG1) did not change the rate of ternary complex formation. These data indicate that the antibodies recognize different epitopes on the enzyme molecule.

Cloning and expression of a cDNA coding for the human platelet-derived growth factor receptor: Evidence for more than one receptor class

International Nuclear Information System (INIS)

Gronwald, R.G.K.; Grant, F.J.; Haldeman, B.A.; Hart, C.E.; O'Hara, P.J.; Hagen, F.S.; Ross, R.; Bowen-Pope, D.F.; Murray, M.J.

1988-01-01

The complete nucleotide sequence of a cDNA encoding the human platelet-derived growth factor (PDGF) receptor is presented. The cDNA contains an open reading frame that codes for a protein of 1106 amino acids. Comparison to the mouse PDGF receptor reveals an overall amino acid sequence identity of 86%. This sequence identity rises to 98% in the cytoplasmic split tyrosine kinase domain. RNA blot hybridization analysis of poly(A) + RNA from human dermal fibroblasts detects a major and a minor transcript using the cDNA as a probe. Baby hamster kidney cells, transfected with an expression vector containing the receptor cDNA, express an ∼ 190-kDa cell surface protein that is recognized by an anti-human PDGF receptor antibody. The recombinant PDGF receptor is functional in the transfected baby hamster kidney cells as demonstrated by ligand-induced phosphorylation of the receptor. Binding properties of the recombinant PDGF receptor were also assessed with pure preparations of BB and AB isoforms of PDGF. Unlike human dermal fibroblasts, which bind both isoforms with high affinity, the transfected baby hamster kidney cells bind only the BB isoform of PDGF with high affinity. This observation is consistent with the existence of more than one PDGF receptor class

T cell clones which share T cell receptor epitopes differ in phenotype, function and specificity

NARCIS (Netherlands)

Yssel, H.; Blanchard, D.; Boylston, A.; de Vries, J. E.; Spits, H.

1986-01-01

Recently, we described a monoclonal antibody (3D6) that reacts with the T cell receptor (Ti) of the T leukemic cell line HPB-ALL and that cross-reacts with 2-10% of the T cells of normal healthy individuals. In this study we report the establishment of T cell clones that are 3D6+ but that differ in

Antibody-induced activation of the epidermal growth factor receptor tyrosine kinase requires the presence of detergent

NARCIS (Netherlands)

Spaargaren, M.; Defize, L. H.; de Laat, S. W.; Boonstra, J.

1990-01-01

Activation of the epidermal growth factor receptor (EGF-R) tyrosine kinase was investigated in membrane preparations as well as intact A431 cells, using anti-EGF-R antibodies directed against extra- and intracellular receptor domains. In vitro assay conditions were mimicked on whole cells by a mild