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Monoclonal Antibodies Specific (monoclonal + antibody_specific)
Selected AbstractsProduction and partial characterization of mouse monoclonal antibodies recognizing common cytokine receptor gamma chain (,c) of human, mouse and primate origin,APMIS, Issue 10 2001KAROLINA LUNDIN Monoclonal antibodies specific for the common cytokine receptor gamma chain, ,c, were produced using traditional hybridoma technology. Fusion of P3X63-Ag8.653 myeloma cells with splenocytes from Balb/c mice immunized with Spodoptera frugiperda insect cells infected with the recombinant baculovirus VL1392-hIL-2R, resulted in several hybridoma cell clones producing monoclonal ,c -specific antibodies. Four of these antibody-producing clones, IIIC3, IIIE8, IG3 and IF10C5, were further characterized by immunoblotting, flow cytometry and ELISA. Data are presented demonstrating that the generated monoclonal antibodies can identify the extracellular domain of the common cytokine receptor , chain of human and mouse origin, and two of the antibodies recognize ,c of primate origin as well. [source] Preoperative hCG, and CA 72-4 are prognostic factors in gastric cancerINTERNATIONAL JOURNAL OF CANCER, Issue 6 2004Johanna Louhimo Abstract In gastric cancer, the role of tumour markers in assessment of prognosis is unconfirmed. In our study, we evaluated the prognostic significance of serum tumour markers carcinoembryonic antigen (CEA), CA 19-9, CA 72-4, CA 242 and free , subunit of human chorionic gonadotropin (hCG,) in gastric cancer. Preoperative serum samples were obtained from 146 patients with gastric cancer, including 29 with stage I, 11 with stage II, 42 with stage III and 64 patients with stage IV cancer. Quantitation of CEA, CA 19-9, CA 72-4 and CA 242 in serum was performed with commercial assays. HCG, was measured with an in-house immunofluorometric assay based on monoclonal antibodies specific for the free ,-subunit of hCG. Survival analysis was performed with Kaplan-Meier life-tables and log-rank test, and with multivariate Cox regression analysis. Disease-specific cumulative 2-year survival rate was 40%. Serum levels of CEA, CA 72-4, CA 242 and hCG, showed significant correlation with stage (p<0.027); for CA 19-9 the association was of borderline significance (p=0.056). Of the studied markers, CA 19-9, CA 72-4, CA 242 and hCG, were found to be prognostic factors in univariate analysis (p< 0.022). In multivariate analysis, stage had the statistically most significant association with prognosis followed by hCG,, tumour histology according to the Laurén classification and by CA 72-4. In gastric cancer, tumour markers hCG, and CA 72-4 are independent prognostic factors in addition to stage and histological type of the tumour. © 2004 Wiley-Liss, Inc. [source] Do G protein-coupled receptors expressed in human lingual epithelium interact with HPV11?JOURNAL OF MEDICAL VIROLOGY, Issue 10 2007Lukasz Durzy Abstract Human papillomaviruses infect epithelia but little is known about the nature of cell surface receptors interacting with the viral particles. It has been proposed that glycosaminoglycans and integrins may be involved in the attachment process. In the present study, the putative interactions of virus-like particles of human papillomavirus type 11 (HPV11), which present a tropism for nasopharyngeal epithelia, with olfactory and taste receptors expressed in the human lingual epithelium were studied. The L1 protein of HPV11 was produced in insect cells. The presence of L1 virus-like particles was analyzed by ELISA using monoclonal antibodies specific for full-size particles and by electron microscopy. Using immunofluorescence, it was observed that virus-like particles interacted with taste buds from murine tongue, with the tagged human olfactory receptor hJCG5 expressed in HEK-293 but not with the tagged taste receptor hT2R4. This therefore suggests that hJCG5 may be involved in the adsorption process of HPV11 to lingual epithelium serving as a so-called "adsorption-adhesive molecule." J. Med. Virol. 79:1545,1554, 2007. © Wiley-Liss, Inc. [source] Distribution pattern of versican, link protein and hyaluronic acid in the rat jreiodontal ligament during exjreimental tooth movementJOURNAL OF PERIODONTAL RESEARCH, Issue 1 2002R. Sato The ability of the jreiodontal ligament (PDL) to rapidly remodel is the basis of orthodontic tooth movement. During the tooth movement, matrix proteoglycans (PGs) may play important roles in spatial, mechanical and biological aspects for the maintenance and repair of the PDL. The aim of this study was to characterize the distribution of a large hyaluronic acid (HA)-binding proteoglycan, versican, link protein (LP) and HA in the rat molar PDL during exjreimental tooth movement by histochemical and immunohistochemical methods. Exjreimental tooth movement was jreformed according to Waldo's method. Histologically, regressive changes, such as decrease of fibroblasts and collagen fibers and exudative change of edema were observed in the compressive side and progressive changes, such as proliferation of fibroblasts and collagen fibers, in the strain side one day after treatment. By 3 days after tooth movement, regressive or progressive changes were not observed in either side. Using monoclonal antibodies specific to versican core protein or LP, the positive immunoreactivity for both molecules was constantly observed throughout the PDL. After the exjreimental force was applied to the tooth, however, the immunostainings of versican and LP became significantly intense only in the compressive side but decreased in the strain side. The intensity in the compressive side was strongest one day after the force was applied and gradually diminished thereafter. HA of both sides did not change during exjreimental tooth movement. Since HA is present in the PDL, large amounts of versican and LP expressed in the compressive side may create large hydrated aggregates via their association with HA that dissipates the compressive force applied to this tissue. [source] A novel mechanism for control of antigenic variation in the haemagglutinin gene family of Mycoplasma synoviaeMOLECULAR MICROBIOLOGY, Issue 4 2000A. H. Noormohammadi High-frequency phase and antigenic variation of homologous lipoprotein haemagglutinins has been seen in both the major avian mycoplasma pathogens, Mycoplasma synoviae and Mycoplasma gallisepticum. The expression and, hence, antigenic variation of the pMGA gene family (encoding these lipoproteins in M. gallisepticum) is controlled by variation in the length of a trinucleotide repeat motif 5, to the promoter of each gene. However, such a mechanism was not detected in preliminary observations on M. synoviae. Thus, the basis for control of variation in the vlhA gene family (which encodes the homologous haemagglutinin in M. synoviae) was investigated to enable comparison with its homologue in M. gallisepticum and with other lipoprotein gene families in mycoplasmas. The start point of transcription was identified 119 bp upstream of the initiation codon, but features associated with control of transcription in other mycoplasma lipoprotein genes were not seen. Comparison of three copies of vlhA revealed considerable sequence divergence at the 3, end of the gene, but conservation of the 5, end. Southern blot analysis of M. synoviae genomic DNA revealed that the promoter region and part of the conserved 5, coding sequence occurred as a single copy, whereas the remainder of the coding sequence occurred as multiple copies. A 9.7 kb fragment of the genome was found to contain eight tandemly repeated regions partially homologous to vlhA, all lacking the putative promoter region and the single-copy 5, end of vlhA, but extending over one of four distinct overlapping regions of the 3, coding sequence. Examination of sequential clones of M. synoviae established that unidirectional recombination occurs between the pseudogenes and the expressed vlhA, with duplication of pseudogene sequence and loss of the corresponding region previously seen in the expressed gene. Expression of the 5, end of two variants of the vlhA gene showed that they differed in their reaction with monoclonal antibodies specific for this region. These data suggest that the control of vlhA antigenic variation in M. synoviae is achieved by multiple gene conversion events using a repertoire of coding sequences to generate a chimeric expressed gene, with the greatest potential for variation generated in the region encoding the haemagglutinin. Thus, completely distinct mechanisms have been adopted to control antigenic variation in homologous gene families. [source] Toward a cure for type 1 diabetes mellitus: diabetes-suppressive dendritic cells and beyondPEDIATRIC DIABETES, Issue 3pt2 2008Nick Giannoukakis Abstract:, Insulin has been the gold standard therapy for diabetes since its discovery and commercial availability. It remains the only pharmacologic therapy for type 1 diabetes (T1D), an autoimmune disease in which autoreactive T cells specifically kill the insulin-producing beta cells. Nevertheless, not even molecularly produced insulin administered four or five times per day can provide a physiologic regulation able to prevent the complications that account for the morbidity and mortality of diabetic patients. Also, insulin does not eliminate the T1D hallmark: beta-cell-specific autoimmunity. In other words, insulin is not a ,cure'. A successful cure must meet the following criteria: (i) it must either replace or maintain the functional integrity of the natural, insulin-producing tissue, the endocrine islets of Langerhans' and, more specifically, the insulin-producing beta cells; (ii) it must, at least, control the autoimmunity or eliminate it altogether; and (iii) it must be easy to apply to a large number of patients. Criterion 1 has been partially realized by allogeneic islet transplantation. Criterion 2 has been partially realized using monoclonal antibodies specific for T-cell surface proteins. Criterion 3 has yet to be realized, given that most of the novel therapies are currently quasi-patient-specific. Herein, we outline the current status of non-insulin-based therapies for T1D, with a focus on cell-based immunomodulation which we propose can achieve all three criteria illustrated above. [source] Blood Lymphocyte Subpopulations, Neutrophil Phagocytosis and Proteinogram During Late Pregnancy and Postpartum in MaresREPRODUCTION IN DOMESTIC ANIMALS, Issue 2 2008R Agrícola Contents The aim of this study was to evaluate peripheral blood lymphocyte subpopulations, neutrophil phagocytic capacity and proteinogram characteristics in mares, during the last trimester of pregnancy and in postpartum. Measurement of phagocytosis and quantification of T-lymphocyte subsets were done by flow cytometry. Quantification of T-lymphocyte subsets was performed with monoclonal antibodies specific for CD2, CD3, CD4 and CD8 cell markers. Natural killer and B-cell counts were estimated mathematically. Serum proteinogram was obtained by electrophoresis. No significant differences were observed between gestation and postpartum on CD4+, CD8+ and NK+ lymphocyte subsets, CD4 : CD8 ratio and phagocytosis. The percentage of cells expressing CD3 (64.2 ± 1.8) and CD2 (68.4 ± 1.7) (Mean ± SEM) was reduced during gestation vs postpartum (69.7 ± 1.5 and 73.8 ± 1.4 respectively) (p < 0.05). During pregnancy, CD19+ (31.6 ± 1.7) was higher than in postpartum (26.2 ± 1.4) (p < 0.05). Total T cells (2911 ± 227 cells/,l), T helper cells (2144 ± 169 cells/,l) and T-cytotoxic cells (767 ± 68 cells/,l) were depressed in pregnancy, when compared with postpartum (4093 ± 337 cells/,l; 3004 ± 276 cells/,l; 1089 ± 94 cells/,l respectively) (p < 0.01). Total white blood cell count was reduced during pregnancy (8815 ± 427 cells/,l) with respect to postpartum (10742 ± 446 cells/,l) (p < 0.01), while neutrophil count did not change. Total proteins, albumin, ,1,,2,,1, ,2, , globulins and albumin : globulin did not differ. Our results suggest that the physiological immune depression occurring in mares, during gestation might be due to T-helper and T-cytotoxic lymphocytes reduction. [source] Morphological, Biochemical and Molecular Characterization of Herpetomonas samuelpessoai camargoi n. subsp., a Trypanosomatid Isolated from the Flower of the Squash Cucurbita moschataTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 1 2001JOAO E. FIORINI ABSTRACT. We report the morphological, biochemical and molecular characteristics of a trypanosomatid isolated from the flower of Cucurbita moschata. Although the trypanosomatid was isolated from a plant, the lack of recognition of Phytomonas-spccific molecular markers based on spliced-leader and ribosomal genes as well as by monoclonal antibodies specific for Phytomonas argues against assigning it to this genus. Because the isolate displayed typical opisthomastigote forms in culture, it is assigned to the genus Herpetomonas. Analysis of randomly amplified polymorphic DNA (RAPD) patterns and characterization of ribosomal SSU and ITS markers suggest that it is more closely related to H. samuelpessoai than to any other species. However, the presence of spined flagellates in culture (displaying lateral expansions of the plasma membrane originating near the flagellar pocket) and isolate-specific RAPD fingerprints argue strongly that the trypanosomatid belongs to a new subspecies, for which the name Herpetomonas samuelpessoai camargoi n. subsp. is proposed. [source] Assessment of in vitro immunity to Mycobacterium tuberculosis in a human peripheral blood infection model using a luciferase reporter construct of M. tuberculosis H37RvCLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 3 2006R. Al-Attiyah Summary Protective immune responses to tuberculosis in man are primarily cell-mediated and require the interaction of specific T cells, cytokines and activated macrophages. In the present study, Mycobacterium tuberculosis H37Rv labelled with luciferase reporter enzyme was used to analyse the anti-mycobacterial immunity in man using an in vitro whole blood infection model. Peripheral blood samples obtained from M. bovis bacille Calmette,Guérin (BCG)-vaccinated tuberculin-positive healthy volunteers (n = 23) were cultured with M. tuberculosis H37Rv reporter strain. The growth of bacteria in the whole blood cultures was monitored after 48 and 96 h of infection. The results showed that the growth of M. tuberculosis was significantly inhibited after 96 h (P < 0·029) of culture. Among the cytokines studied, interleukin (IL)-10 and IL-12 were not detected at all, whereas low levels of interferon (IFN)-, after 96 h (0·4 IU/ml) and tumour necrosis factor (TNF)-, after 48 (135 pg/ml) and 96 h (47 pg/ml) of culture were detected in the supernatants of whole blood infected with M. tuberculosis. The magnitude of bacterial growth correlated directly with the concentration of TNF-, detected after 48 h (r = 0·722) and 96 h (r = 0·747) of culture (P , 0·0001 and P , 0·0001, respectively). However, the addition of monoclonal antibodies specific to TNF-, and IFN-, to the blood cultures did not alter mycobacterial growth indicating the role of other mechanisms/factors in restricting the growth of M. tuberculosis in whole blood cultures. [source] Assessment of CD8 involvement in T,cell clone avidity by direct measurement of HLA-A2/Mage3 complex density using a high-affinity TCR like monoclonal antibodyEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 10 2005Karine Bernardeau Abstract Peptide affinity for MHC molecules determines the number of MHC/peptide complexes stabilized at the cell surface in in vitro tests or in vaccination protocols. We isolated a high affinity monoclonal antibody specific for the HLA-A2/Mage3 complex that enables an equilibrium binding assay to be performed on T2 cell line loaded with a range of Mage3 peptides. Binding of Mage3 to the HLA-A2 molecule can be modeled by a standard receptor-ligand interaction characterized by an affinity constant. This model enables the measurement of the affinity of other immunogenic peptides for HLA-A2 by a competition test and the calculation of the density of complexes stabilized at the T2 cell surface for all peptide concentrations. Quantification of the HLA-A2/Mage3 complexes at target cell surfaces was used to estimate the number of complexes required to reach cytotoxicity ED50 of human T,cell clones sorted from an unprimed repertoire. We confirm with this antibody the direct relationship between clone avidity and TCR affinity, and the moderate contribution of the CD8 co-receptor in the reinforcement of TCR-MHC/peptide contact. Nevertheless, CD8 plays a critical role in the amplification of the specific signal to establish an efficient T,cell response at low specific complex densities found in physiological situations. [source] Antibodies to non-bilayer phospholipid arrangements induce a murine autoimmune disease resembling human lupusEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 2 2004Isabel Baeza Abstract Antibodies recognizing non-bilayer phospholipid arrangements (NPA) in membrane models and in cell membranes in vivo, triggered an autoimmune-like disease in mice. This exhibited features similar to human lupus and was induced by injecting mice either with the H308 monoclonal antibody specific to NPA, with sera from mice which already had developed the autoimmune disease, or withliposomes treated with the NPA inductors chlorpromazine or procainamide; or with these NPA inductors alone. All these procedures revealed the involvement of antibodies to non-bilayer phospholipids in inducing this autoimmune-like disease. Unraveling the mechanisms of these antibodies might contribute to a better understanding of the molecular and immunological basis of autoimmune diseases like lupus and, hopefully, towards the development of better therapeutic strategies. [source] Pathogenesis of multifocal micronodular pneumocyte hyperplasia and lymphangioleiomyomatosis in tuberous sclerosis and association with tuberous sclerosis genes TSC1 and TSC2PATHOLOGY INTERNATIONAL, Issue 8 2001Hiroshi Maruyama Tuberous sclerosis (TSC) is a rare, genetically determined disorder / familial tumor syndrome, currently diagnosed using specific clinical criteria proposed by Gomez, including the presence of multiorgan hamartomas. Pulmonary involvement in TSC is well known as pulmonary lymphangioleiomyomatosis (LAM), which has an incidence of 1,2.3% in TSC patients. LAM has immunohistochemical expression of both smooth-muscle actin and a monoclonal antibody specific for human melanoma, HMB-45. It has recently been reported that multifocal micronodular pneumocyte hyperplasia (MMPH) associated with TSC should be considered as a distinct type of lung lesion, whether it occurs with or without LAM. Two predisposing genes have been found in families affected by TSC; approximately half of the families show linkage to TSC1 at 9q34.3, and the other half show linkage to TSC2 at 16p13.3. TSC genes are considered to be tumor suppressor genes, and mutations in them may lead to abnormal differentiation and proliferation of cells. Tuberin, the TSC2 gene product, has recently been found to be expressed in LAM and MMPH. In this article we discuss the histogenesis and genetic abnormalities of neoplastic lesions associated with TSC, and we review the current understanding of the pathogenesis of pulmonary hamartomatous lesions such as LAM and MMPH in TSC. [source] Rituximab for the treatment of post-bone marrow transplantation refractory hemolytic anemia in a child with Omenn's syndromePEDIATRIC TRANSPLANTATION, Issue 5 2007Briuglia Silvana Abstract:, Omenn's syndrome is a rare severe combined immunodeficiency that kills affected subjects before the end of the first year of life unless patients are treated with bone marrow transplantation (BMT). Unfortunately, post-BMT patients may develop autoimmune diseases, such as autoimmune hemolytic anemia (AIHA), which sometimes fails to respond to standard therapies. Rituximab is a chimeric, human, immunoglobulin G1/k monoclonal antibody specific for the CD20 antigen expressed on the surface of B lymphocytes. Rituximab is currently only labeled for treatment of B-cell lymphoproliferative disorders, such as B-cell non-Hodgkin's lymphoma and follicular lymphoma; however, it is also employed in the treatment of a variety of disorders mediated by auto-antibodies, such as AIHA and transplant-related autoimmune disorders. Herein, we describe the case of a 23-month-old male child with Omenn's syndrome, who had undergone BMT and was successfully treated with rituximab (375 mg/m2 intravenously, weekly for three times) for refractory post-BMT hemolytic anemia. Our findings evidence that rituximab should be considered for treatment of post-BMT AIHA refractory to traditional therapy also in children with primary immunodeficiencies; furthermore, rituximab might represent a means to obtain remissions without the toxic effects associated with corticosteroid and immunosuppressive agents. [source] A novel diagnostic monoclonal antibody specific for Helicobacter pylori CagA of East Asian typeAPMIS, Issue 12 2009AIKO YASUDA Molecular biological and epidemiological studies have suggested that Helicobacter pylori producing East Asian CagA protein variant is more virulent than that producing Western CagA. In the present study, we developed and validated an enzyme-linked immunosorbent assay (ELISA) using a monoclonal antibody specifically recognizing East Asian CagA-positive H. pylori. A total of 32 H. pylori strains were tested and the data were subjected to receiver-operator characteristic (ROC) curve analysis. The accuracy of the test, determined by calculating the area under the curve, was 0.96, which indicated a high level of accuracy. At the ROC optimized cutoff, the sensitivity and specificity of our ELISA method were 88.0% and 100%, respectively. The validated ELISA showed good performance in terms of sensitivity and specificity. These results suggest that this test is suitable for the diagnostic detection of East Asian CagA carrying strains. We also analyzed the localization of the CagA protein in H. pylori -infected gastric mucosa with fluorescence immunohistochemistry, and found that CagA protein expression was up-regulated by adhesion to epithelial cells. [source] Structure of the Fab fragment from F124, a monoclonal antibody specific for hepatitis B surface antigenACTA CRYSTALLOGRAPHICA SECTION D, Issue 8 2000F. A. Saul The crystal structure of the Fab fragment from the monoclonal anti-preS2 antibody F124 (IgG1,,) has been solved by molecular replacement and refined at 3.0,Å resolution. The Fab crystallizes with two independent molecules in the asymmetric unit. F124 recognizes an epitope contained within the preS2 segment between residues 120 and 132 of the surface antigen of hepatitis B virus. The antibody shows a high affinity for the glycan N-linked to Asn123, but it also cross-reacts with the non-glycosylated peptide fragment 120,132. Although crystallization was performed in the presence of an eightfold excess of the cross-reactive peptide, no evidence for the ligand was found in the antigen-binding site, which is close to a neighbouring molecule in the crystal lattice. The antigen-binding site has a groove-like topology which is modulated with pocket-like cavities. It is characterized by a large number of tyrosine and aspartate residues. The importance of germ-line mutations at the binding site is discussed. [source] A monoclonal antibody specific for a unique biomarker, virenose, in a lipopolysaccharide of Coxiella burnetiiCLINICAL MICROBIOLOGY AND INFECTION, Issue 2009K. Palkovicova No abstract is available for this article. [source] | |||||||||||||