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Immunoglobulin G (immunoglobulin + g)
Kinds of Immunoglobulin G Terms modified by Immunoglobulin G Selected AbstractsBiological Sensor Platforms: Photoluminescence Detection of Biomolecules by Antibody-Functionalized Diatom Biosilica (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 6 2009Mater. Microscopic shells of single-celled algae called diatoms possess intricate nanoscale features composed of photoluminescent biosilica. On page 926, the functionalization of the 10 µm centric diatom Cyclotella (center image) with the antibody Immunoglobulin G, and its use as a biosensor for immunocomplex formation are reported by D. K. Gale et al. Such formation is visible across the entire biosilica surface using FITC-labeled antigen (green image) and antigen labeled with 10 nm gold nanoparticles (top image). [source] Specific Protein Detection Using Thermally Reduced Graphene Oxide Sheet Decorated with Gold Nanoparticle-Antibody ConjugatesADVANCED MATERIALS, Issue 32 2010Shun Mao A highly sensitive and selectivefield-effect transistor biosensor using thermally reduced graphene oxide (TRGO) sheet decorated with gold nanoparticle-antibody conjugates is demonstrated. Probe antibody (anti-Immunoglobulin G) is labeled on the surface of the TRGO sheet through gold nanoparticles and electrical detection of the protein binding (Immunoglobulin G and anti-Immunoglobulin G) is accomplished by FET and dc measurements. [source] Diphenyl diselenide protects against hematological and immunological alterations induced by mercury in miceJOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 5 2008Ricardo Brandão Abstract Mercury is a heavy metal that can cause a variety of toxic effects on the organism, such as hematological and immunological alterations. In the present investigation, deleterious effects of mercury-intoxication in mice and a possible protective effect of diphenyl diselenide (PhSe)2 were studied. Male adult Swiss albino mice received daily a pretreatment with (PhSe)2 (15.6 mg/kg, orally) for 1 week. After this week, mice received daily mercuric chloride (1 mg/kg, subcutaneously) for 2 weeks. A number of hematological (erythrocytes, leukocytes, platelets, hemoglobin, hematocrit, reticulocytes, and leukocytes differential) and immunological (immunoglobulin G and M plasma concentration) parameters were evaluated. Another biomarker of tissue damage, lactate dehydrogenase (LDH), was also determined. The results demonstrated that mercury exposure caused a reduction in the erythrocyte, hematocrit, hemoglobin, leukocyte, and platelet counts and an increase in the reticulocyte percentages. (PhSe)2 was effective in protecting against the reduction in hematocrit, hemoglobin, and leukocyte levels. (PhSe)2 ameliorated reticulocyte percentages increased by mercury. However, (PhSe)2 was partially effective in preventing against the decrease in erythrocyte and platelet counts. Immunoglobulin G and M concentrations and LDH activity were increased by mercury exposure, and (PhSe)2 was effective in protecting against these effects. In conclusion, (PhSe)2 was effective in protecting against hematological and immunological alterations induced by mercury in mice. © 2008 Wiley Periodicals, Inc. J Biochem Mol Toxicol 22:311,319, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20242 [source] Pyoderma Gangrenosum in Association with Autoimmune Neutropenia of InfancyPEDIATRIC DERMATOLOGY, Issue 6 2008Anisha J. Mehta M.R.C.P. Histology showed changes consistent with pyoderma gangrenosum and the ulcer resolved rapidly with super-potent topical steroids under occlusion. Blood tests revealed a persistent neutropenia. Immunoglobulin G (IgG) antineutrophil antibodies were detected in the serum, directed against human neutrophil antigen (HNA)-1a. Bone marrow studies showed normocellular marrow with no evidence of dysplasia. T and B cell subsets and karotype analysis were normal. Autoimmune neutropenia is an uncommon self-limiting condition in young children. Pyoderma gangrenosum is rare in infants, although the buttocks are a common site of involvement in this age group. Pyoderma gangrenosum in infancy can be associated with systemic disease as in adults, particularly myelodysplasia and leukemia, arthritis and inflammatory bowel disease. However, the association of pyoderma gangrenosum and autoimmune neutropenia of infancy has not previously been reported. [source] Development of biosensor based on imaging ellipsometryPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 4 2008G. Jin Abstract The concept of biosensor based on imaging ellipsometry was proposed ten years ago. Its principle and the methodology as well as some solutions to problems which have to be faced during the development are mentioned. Its properties of phase sensitive, high throughput and fast sampling, as well as label-free, sensitivity better than 1 ng/ml for Immunoglobulin G, and real-time analysis for protein interaction process, etc. provide a potential for applications in biomedicine field. The recent biosensing development with total internal reflection imaging ellipsometry is presented also. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Effect of a combination of extract from several plants on Cell-mediated and humoral immunity of patients with advanced ovarian cancerPHYTOTHERAPY RESEARCH, Issue 5 2006N. Kormosh Abstract The influence of a plant preparation AdMax (Nulab Inc., Clearwater, FL, USA) on immunity in ovarian cancer patients was studied. The preparation is a combination of dried ethanol/water extracts from roots of Leuzea carthamoides, Rhodiola rosea, Eleutherococcus senticosus and fruits of Schizandra chinensis. Twenty eight patients with stage III,IV epithelial ovarian cancer were treated once with 75 mg/m2 cisplatin and 600 mg/m2 cyclophosphamide. Peripheral blood was collected 4 weeks after the chemotherapy. Subclasses of T, B and NK lymphocytes were tested for in the blood samples: CD3, CD4, CD5, CD7, CD8, CD11B, CD16, CD20, CD25, CD38, CD45RA, CD50, CD71 and CD95. Immunoglobulin G, A and M concentrations were also determined. Changes were observed in the following T cell subclasses: CD3, CD4, CD5 and CD8. In patients who took AdMax (270 mg a day) for 4 weeks following the chemotherapy, the mean numbers of the four T cell subclasses were increased in comparison with the mean numbers of the T cell subclasses in patients who did not take AdMax. In patients who took AdMax, the mean amounts of IgG and IgM were also increased. The obtained results suggest that the combination of extracts from adaptogenic plants may boost the suppressed immunity in ovarian cancer patients who are subject to chemotherapy. Copyright © 2006 John Wiley & Sons, Ltd. [source] Elevated Epstein,Barr virus-encoded nuclear antigen-1 immune responses predict conversion to multiple sclerosisANNALS OF NEUROLOGY, Issue 2 2010Jan D. Lünemann MD Objective The aims of the study were to determine the immune responses to candidate viral triggers of multiple sclerosis (MS) in patients with clinically isolated syndromes (CISs), and to evaluate their potential value in predicting conversion to MS. Methods Immune responses to Epstein,Barr virus (EBV), human herpesvirus 6, cytomegalovirus (HCMV), and measles were determined in a cohort of 147 CIS patients with a mean follow-up of 7 years and compared with 50 demographically matched controls. Results Compared with controls, CIS patients showed increased humoral (p < 0.0001) and cellular (p = 0.007) immune responses to the EBV-encoded nuclear antigen-1 (EBNA1), but not to other EBV-derived proteins. Immunoglobulin G (IgG) responses to other virus antigens and frequencies of T cells specific for HCMV and influenza virus gene products were unchanged in CIS patients. EBNA1 was the only viral antigen with which immune responses correlated with number of T2 lesions (p = 0.006) and number of Barkhof criteria (p=0.001) at baseline, and with number of T2 lesions (p = 0.012 at both 1 and 5 years), presence of new T2 lesions (p = 0.003 and p = 0.028 at 1 and 5 years), and Expanded Disability Status Scale score (p = 0.015 and p = 0.010 at 1 and 5 years) during follow-up. In a univariate Cox regression model, increased EBNA1-specific IgG responses predicted conversion to MS based on McDonald criteria (hazard ratio [95% confidence interval], 2.2 [1.2-4.3]; p = 0.003). Interpretation Our results indicate that elevated immune responses toward EBNA1 are selectively increased in CIS patients and suggest that EBNA1-specific IgG titers could be used as a prognostic marker for disease conversion and disability progression. ANN NEUROL 2010;67:159,169 [source] Circulating insulin antibodies: influence of continuous subcutaneous or intraperitoneal insulin infusion, and impact on glucose controlDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 6 2009R. P. Radermecker Abstract The purification of animal insulin preparations and the use of human recombinant insulin have markedly reduced the incidence, but not completely suppressed, the development of anti-insulin antibodies (IAs). Advances in technologies concerning the mode of delivery of insulin, i.e. continuous subcutaneous insulin infusion (CSII), continuous peritoneal insulin infusion (CPII) and more recently inhaled insulin administration, appear to significantly increase circulating levels of immunoglobulin G (IgG) anti-IAs in diabetic patients. However, the increase is usually moderate and mostly transient as compared to previous observations with poorly purified animal insulin preparations. The clinical impact of these circulating anti-IAs remains unclear. Nevertheless, several studies have suggested that antibodies could retard insulin action, leading to a worsening of postprandial hyperglycaemia and/or serve as a carrier, thus leading to unexpected hypoglycaemia. CPII may be associated with more marked and sustained increase in IAs levels, possibly related to the use of an unstable insulin and the formation of immunogenic aggregates of insulin. The possible clinical consequences of these high levels of IAs remain to be evaluated because a low-glucose morning syndrome or severe insulin resistance with ketone bodies production have been reported in some cases. In conclusion, even if CSII and CPII may promote the development of circulating IAs, this increase does not lead to immunological insulin resistance, compared to that previously described with animal non-purified insulin preparations, and seems to have only marginal influence on blood glucose control or complications in most diabetic patients. Copyright © 2009 John Wiley & Sons, Ltd. [source] CE-based noncompetitive immunoassay for immunoglobulin G in bovine colostrum productsELECTROPHORESIS, Issue 21 2007Jin Zhao Abstract A CE-based noncompetitive immunoassay for IgG in bovine colostrum products was established. FITC-labeled protein G (FITC-PrG) was tagged through noncovalent bindings to the Fc region of the mouse monoclonal antibovine IgG (Ab). The FITC-PrG, Ab, and IgG formed a sandwiched immunocomplex FITC-PrG-Ab-IgG under optimal incubation conditions. The immunocomplex was separated and analyzed by CZE with LIF detection in less than 2,min in an uncoated fused-silica capillary. Addition of PEG 20,000 (PEG 20M) in the running buffer significantly suppressed analyte adsorption and thus improved the reproducibility and the resolution. The precision of the method was 5.1% (n,=,7). A linear relationship was established for the IgG concentration in the range of 1,5,mg/L with a linear correlation coefficient (r,=,0.9917). The LOD was 0.1,mg/L (S/N,=,3). The method was successfully applied for the determination of IgG in bovine colostrum products and satisfactory results were achieved. [source] Fast immobilization of probe beads by dielectrophoresis-controlled adhesion in a versatile microfluidic platform for affinity assayELECTROPHORESIS, Issue 19 2005Janko Auerswald Dr. Abstract The use of probe beads for lab-on-chip affinity assays is very interesting from a practical point of view. It is easier to handle and trap beads than molecules in microfluidic systems. We present a method for the immobilization of probe beads at defined areas on a chip using dielectrophoresis (DEP)-controlled adhesion. The method is fast, i.e., it takes between 10 and 120,s , depending on the protocol , to functionalize a chip surface at defined areas. The method is versatile, i.e., it works for beads with different types of probe molecule coatings. The immobilization is irreversible, i.e., the retained beads are able to withstand high flow velocities in a flow-through device even after the DEP voltage is turned off, thus allowing the use of conventional high-conductivity analyte buffers in the following assay procedure. We demonstrate the on-chip immobilization of fluorescent beads coated with biotin, protein,A, and goat,antimouse immunoglobulin G (IgG). The number of immobilized beads at an electrode array can be determined from their fluorescence signal. Further, we use this method to demonstrate the detection of streptavidin and mouse IgG. Finally, we demonstrate the feasibility of the parallel detection of different analyte molecules on the same chip. [source] Carbamazepine-induced drug-induced hypersensitivity syndrome in a 14-year-old Japanese boyEPILEPSIA, Issue 12 2008Yuka Suzuki Summary Drug-induced hypersensitivity syndrome (DIHS) is a life-threatening idiosyncratic drug reaction, and an early accurate diagnosis is essential for its treatment. We describe a 14-year-old boy with localization-related epilepsy, who developed severe adverse cutaneous and systemic reactions after 3 weeks of carbamazepine administration. During the course of the clinical symptoms, reactivation of human herpesvirus 6 (HHV-6) was proven by detection of the HHV-6 genome in serum and elevation of HHV-6 immunoglobulin G (IgG). He fulfilled the newly established criteria for DIHS. Among eight identified medications that can precipitate DIHS, four are antiepileptic drugs. Establishing a treatment strategy for DIHS is warranted to improve its outcome. Therefore, it is important to raise awareness of DIHS among epileptologists. [source] Clinical importance of antibodies against platelet activating factor in antiphospholipid syndrome manifestationsEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 7 2000Tektonidou Background We assessed whether antibodies against platelet activating factor (PAF) are related to the presence of antiphospholipid syndrome (APS) clinical manifestations, in particular thrombosis, in patients with connective tissue diseases. Materials and methods Anti-PAF, anticardiolipin (aCL), anti,2 glycoprotein I (anti,2GPI) and antiphosphatidylcholine (anti-PC) antibodies were determined in 52 patients with APS, 29 patients with systemic lupus erythematosus (SLE) aCL but without APS, 30 patients with SLE without aCL, and 30 patients with scleroderma. A new enzyme-linked immunosorbent assay (ELISA) was developed for determining anti-PAF antibodies in a bovine serum-free fashion. Results The ELISA showed high specificity. Homologous inhibition experiments showed 60,70% inhibition. Anti-PAF antibodies were found in 18/52 APS patients, 10/29 SLE/aCL+ patients, 9/30 SLE/aCL, patients and 3/30 scleroderma patients. Anti-PAF antibodies were significantly associated with anti-PC antibodies (odds ratio [OR] 12.7, P < 0.01), and there was a modest association with immunoglobulin G (IgG) aCL (OR 3.1, P > 0.10), but not with IgM aCL or anti,2GPI. Three SLE/aCL+ patients and five SLE/aCL, patients had clinical manifestations characteristic of APS. All these patients had anti-PAF antibodies, while none had high titres of aCL or anti,2GPI antibodies and only one had anti-PC antibodies. Among the combined APS and SLE groups, the presence of anti-PAF antibodies was significantly associated with clinical manifestations which are characteristic of APS (OR 2.6, P = 0.02). The effect was independent of IgG aCL and anti,2GPI antibodies. Conclusions Anti-PAF antibodies are common in APS and SLE and comprise an independent factor for the development of thrombosis. Several patients experiencing thromboses have anti-PAF antibodies without other antiphospholipid specificities. [source] Vorinostat enhances the antimyeloma effects of melphalan and bortezomibEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 3 2010Richard A. Campbell Abstract Objectives:, Examine the antitumor activity of the histone deacetylase inhibitor vorinostat's antitumor activity against multiple myeloma (MM) using cell lines and a murine xenograft model. Methods:, RPMI8226, U266, and MM1S cells were cultured for 48 h in the presence of media, vorinostat, melphalan, or bortezomib alone, or combinations of vorinostat with melphalan or bortezomib. Cell proliferation was measured using the MTS [3-(4,5-dimethylthiazol-2yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfphophenyl)-2H-tetrazolium, inner salt] assay. Severe combined immunodeficient mice bearing LAG,-1B tumors were treated with vorinostat [30, 60, or 100 mg/kg daily for five consecutive days per week (qd×5d), 100 or 300 mg/kg daily for 2 d/wk (qd×2d)], melphalan (1, 3, or 10 mg/kg qd×1d), bortezomib (0.25 or 0.5 mg/kg qd×2d), or combinations thereof for 35 d. Tumor growth was determined via measurement of human immunoglobulin G (hIgG) levels and tumor volume. Results and Conclusions:, Vorinostat enhanced the anti-MM effects of melphalan and bortezomib in vitro. Synergism was observed with vorinostat and melphalan in RPMI8226 and U266 cell lines. Vorinostat 100 mg/kg in combination with melphalan 3 mg/kg resulted in significant inhibition of tumor growth in vivo, compared with control (tumor volume P = 0.0001; hIgG P = 0.0001), single-agent vorinostat (tumor volume P = 0.0025; hIgG P = 0.0137), and single-agent melphalan (tumor volume P = 0.0043; hIgG P = 0.0426). Vorinostat also enhanced the antimyeloma effects of bortezomib in vivo. Vorinostat enhances the anti-MM activity of melphalan and bortezomib in vitro and in vivo. This study provides rationale for further evaluation of vorinostat in combination with chemotherapeutic agents and bortezomib for the treatment of MM. [source] Arsenic trioxide is effective in the treatment of multiple myeloma in SCID miceEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 3 2004Philippe Rousselot Abstract: Objectives :,Pharmacological concentrations of arsenic trioxide (ATO) and organic arsenic melarsoprol induce apoptosis in malignant plasma cells. In an attempt to further document the interest of the arsenic in vivo, we treated severe combined immunodeficient (SCID) mice transplanted with human myeloma cells by ATO or melarsoprol. Methods :,Fifty-two SCID mice were irradiated before intraperitoneal (i.p.) injection of plasma cells from five myeloma patients. Engraftment was assessed by serial measurement of the human monoclonal immunoglobulin G (HuMIgG) concentration in mouse serum. Treatment with ATO (10 ,g/g i.p. 5 d a week), melarsoprol (30 ,g/g i.p. 5 d a week) or phosphate buffer saline was started when a sustained growth of the tumor cells was demonstrated. Results :,Seventeen mice developed the human tumor. A significant decrease in HuMIgG amounts was observed in three of five mice of the ATO group, including two that achieved an apparent complete remission persisting up to 5 months after ATO discontinuation. In these mice, no human plasma cells were detected in tissue samples collected postmortem. Soluble human interleukin-6 receptor amount, measured in mice sera as a surrogate marker of the plasma cell proliferation, varied in parallel with HuMIgG concentration. A significant difference in survival was observed between control and ATO treated mice (113 and 158 d, respectively; P = 0.01) whereas no difference could be evidenced in control and melarsoprol groups. Conclusion :,Present study confirms in vivo the in vitro effects of ATO on myeloma cells. Delayed relapses were observed suggesting that prolonged or maintenance therapy has to be considered in future clinical trials. Whether or not this will translate into clinically relevant effect of the drug in myeloma patients deserves further consideration. [source] Brain barrier dysfunction in Cuban Epidemic Optic NeuropathyEUROPEAN JOURNAL OF NEUROLOGY, Issue 6 2008A. González-Quevedo Monteagudo Background and purpose:, There are practically no references to cerebrospinal fluid(CSF) studies in tropical or nutritional neuropathies. In the present paper we present the results of CSF studies in patients with Cuban Epidemic Optic Neuropathy (CEON) during epidemic and endemic periods, with an appraisal as to the contribution of brain barriers, function in the pathophysiology of this disease. Methods:, Two hundred and five patients with CEON were studied during the epidemic period (1992,1993) and 12 patients outside the outbreak (1995,1997). CSF protein determination and electrophoresis were carried out, as well as serum and CSF albumin and immunoglobulin G (IgG) quantitation for calculating IgG and Qalb indexes, in order to evaluate intrathecal IgG synthesis and the permeability of the blood,CSF barrier (B-CSF B). Results:, One fourth of the patients had increased permeability of the B-CSF B, but damage was more frequent between 16 and 60 days from onset of disease, disappearing after 120 days. B-CSF B dysfunction was more prevalent in patients with severe neurological impairment, although it was not related to the severity of ophthalmological damage. The group of patients studied outside of the outbreak (endemic period) showed similar results. Discussion:, The possible association of increased permeability of the B-CSF B with oxidative stress, which lies on the basis of this epidemic outbreak, is discussed. [source] Pemphigus mouse model as a tool to evaluate various immunosuppressive therapiesEXPERIMENTAL DERMATOLOGY, Issue 3 2009Yujiro Takae Abstract:, Pemphigus vulgaris (PV) is an autoimmune bullous disease caused by immunoglobulin G (IgG) autoantibodies against desmoglein 3 (Dsg3). We have generated an active disease mouse model for PV by adoptive transfer of Dsg3,/, lymphocytes. In this study, we investigated the benefits and limitations of this model as a tool to evaluate various immunosuppressive therapeutic strategies. We used the following three measurements to evaluate the effects of the drugs during the time course: Dsg3 enzyme-linked immunosorbent assay scores that represent the level of production of anti-Dsg3 IgG, body weight loss that reflects the severity of oral erosions and PV score that reflects the extent of skin lesions. We examined various immunosuppressive agents currently used to treat patients with PV model mice in preventive protocol. Cyclophosphamide almost completely suppressed the production of anti-Dsg3 IgG, development of body weight loss and the appearance of the PV phenotype in contrast with the control group without the drug. Azathioprine, cyclosporin A and tacrolimus hydrate also showed suppressive effects to various degrees. However, methylprednisolone and dexamethasone failed to show significant effects in contrast to the findings reported in humans. Knowing the advantages and limitations of this model will provide an important foundation for the future evaluation and development of novel therapeutic strategies. [source] Oral vaccination of mice against Helicobacter pylori with recombinant Lactococcus lactis expressing urease subunit BFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 3 2009Qing Gu Abstract To determine whether a protective immune response could be elicited by oral delivery of a recombinant live bacterial vaccine, Helicobacter pylori urease subunit B (UreB) was expressed for extracellular expression in food-grade bacterium Lactococcus lactis. The UreB-producing strains were then administered orally to mice, and the immune response to UreB was examined. Orally vaccinated mice produced a significant UreB-specific serum immunoglobulin G (IgG) response. Specific anti-UreB IgA responses could be detected in the feces of mice immunized with the secreting lactococcal strain. Mice vaccinated orally were significantly protected against gastric Helicobacter infection following a challenge with H. pylori strain SS1. In conclusion, mucosal vaccination with L. lactis expressing UreB produced serum IgG and UreB-specific fecal IgA, and prevented gastric infection with H. pylori. [source] Carotenoid and melanin-based ornaments signal similar aspects of male quality in two populations of the common yellowthroatFUNCTIONAL ECOLOGY, Issue 1 2010Peter O. Dunn Summary 1.,Female preferences for particular male ornaments may shift between populations as a consequence of ecological differences that change the reliability and detectability of the ornament, but few studies have examined how ornaments function in different populations. 2.,We examined the signalling function of male plumage ornaments in a warbler, the common yellowthroat (Geothlypis trichas), breeding in New York (NY) and Wisconsin (WI), USA. Males have two prominent ornaments: a black facial mask pigmented with melanin and a yellow bib pigmented by carotenoids. Previous studies in WI indicate that the size of the mask, and not the bib, is primarily related to female choice and male reproductive success. In NY, however, the pattern is reversed and attributes of the bib (size and colour), and not the mask, are the target of sexual selection. 3.,We found that brightness of the yellow bib was the best signal of humoral immunity (immunoglobulin G) in NY and mask size was the best signal in WI, after controlling for breeding experience and capture date. Thus, similar aspects of male quality appeared to be signalled by different ornaments in different populations. 4.,There was no difference between populations in the level of plasma carotenoids or the prevalence of malarial parasites, which may affect the costs and benefits of choosing males with particular ornaments in each location. 5.,Even though females in different populations prefer different ornaments produced by different types of pigments, these ornaments appear to be signalling similar aspects of male quality. Our results caution against inferring the function of particular ornaments based simply on their type of pigment. [source] Human leukocyte antigen DR status and clinical features in Japanese patients with type 1 autoimmune hepatitisHEPATOLOGY RESEARCH, Issue 1 2008Yasuhiro Miyake Aim:, Human leukocyte antigen (HLA) DR status affects the clinical features of autoimmune hepatitis. In Caucasians, patients with DR3 have poorer outcomes. In Japan, the relationship between HLA DR status and clinical features has yet to be fully examined. Methods:, We investigated 79 patients with type 1 autoimmune hepatitis who underwent liver biopsy and were screened for HLA DR status by the polymerase chain reaction sequence specific oligonucleotide hybridization method. Results:, Fifty-five patients had DR4 and 23 had DR2. Thirteen patients had both DR2 and DR4. None had DR3. Of patients aged <30 years, 70% did not have DR4. A tendency toward higher serum levels of immunoglobulin G was seen in patients with DR4 compared to those without, while patients with neither DR2 nor DR4 had lower serum levels of immunoglobulin G than those with only DR2 and those with only DR4. Patients with DR2 had a lower frequency of concurrentautoimmune disease. Concurrence of thyroid disease was seen only in patients with DR4. The cumulative incidental rate of the normalization of serum alanine aminotransferase levels within six months after the introduction of corticosteroid treatment was not associated with HLA DR status. Conclusion:, HLA DR status is considered to affect the clinical features of Japanese patients with type 1 autoimmune hepatitis. Japanese patients with DR2 may have different clinical features from others. In addition, diagnoses of type 1 autoimmune hepatitis should be made carefully in Japanese patients with neither DR2 nor DR4 and in those aged <30 years. [source] The effect of combination antiretroviral therapy on CD5 B- cells, B-cell activation and hypergammaglobulinaemia in HIV-1-infected patientsHIV MEDICINE, Issue 5 2005BE Redgrave Objectives This study assessed B-cell activation, CD5 B-cells and circulating immunoglobulin levels in HIV-infected patients treated with combination antiretroviral therapy (CART). Methods Measurement of plasma immunoglobulin levels and electrophoresis of plasma proteins, and analyses of total numbers of B-cells and B-cells expressing CD38 and CD5 in whole blood, were undertaken in 47 consecutive HIV-1-infected patients attending an out-patient clinic. Results All HIV-infected patients had similar percentages and numbers of B-cells. Proportions of CD5 B-cells in all HIV-infected patients were significantly lower than those in HIV-negative controls. Aviraemic HIV-infected patients on CART had lower percentages of CD5, CD38 and CD5 CD38 B-cell subsets and lower plasma levels of immunoglobulin G (IgG) and immunoglobulin A (IgA) than viraemic HIV-infected patients (untreated or on CART). However, 33,37% of aviraemic HIV-infected patients had IgG and IgA levels above the 95th percentile of the normal range defined in HIV-seronegative donors. In aviraemic HIV-infected patients, plasma IgA levels correlated only with proportions of activated (CD38) B-cells. IgG levels did not correlate with the proportions of B-cell subsets or any marker of HIV disease activity. Monoclonal immunoglobulins were not detected in any plasma sample. Conclusions Aviraemic HIV-infected patients on CART have lower plasma levels of IgG and IgA than viraemic HIV-infected patients, but levels are often above the normal range. CD5 B-cell numbers are depressed, so these cells are unlikely to contribute to hypergammaglobulinaemia in HIV-infected patients. [source] Engineering therapeutic monoclonal antibodiesIMMUNOLOGICAL REVIEWS, Issue 1 2008Xiao-yun Liu Summary: During last two decades, the chimerization and humanization of monoclonal antibodies (mAbs) have led to the approval of several for the treatment of cancer, autoimmune diseases, and transplant rejection. Additional approaches have been used to further improve their in vivo activity. These include combining them with other modalities such as chemotherapy and redesigning them for improved pharmacokinetics, effector function, and signaling activity. The latter has taken advantage of new insights emerging from an increased understanding of the cellular and molecular mechanisms that are involved in the interaction of immunoglobulin G with Fc receptors and complement as well as the negative signaling resulting from the hypercrosslinking of their target antigens. Hence, mAbs have been redesigned to include mutations in their Fc portions, thereby endowing them with enhanced or decreased effector functions and more desirable pharmacokinetic properties. Their valency has been increased to decrease their dissociation rate from cells and enhance their ability to induce apoptosis and cell cycle arrest. In this review we discuss these redesigned mAbs and current data concerning their evaluation both in vitro and in vivo. [source] Decay-accelerating factor 1 (Daf1) deficiency exacerbates xenobiotic-induced autoimmunityIMMUNOLOGY, Issue 1 2010Christopher B. Toomey Summary Absence of decay-accelerating factor 1 (Daf1) has been shown to enhance T-cell responses and autoimmunity via increased expression of specific cytokines, most notably interferon (IFN)-,. To determine if Daf1 deficiency can exacerbate IFN-,-dependent murine mercury-induced autoimmunity (mHgIA), C57/BL6 Daf1+/+ and Daf1,/, mice were exposed to mercuric chloride (HgCl2) and examined for differences in cytokine expression, T-cell activation and features of humoral autoimmunity. In the absence of Daf1, mHgIA was exacerbated, with increased serum immunoglobulin G (IgG), anti-nuclear autoantibodies (ANAs) and anti-chromatin autoantibodies. This aggravated response could not be explained by increased T-cell activation but was associated with increased levels of IFN-,, interleukin (IL)-2, IL-4 and IL-10 but not IL-17 in Daf1-deficient mice. Anti-CD3/anti-CD28 costimulation of Daf1,/, CD4+ T cells in vitro was also found to increase cytokine expression, but the profile was different from that of mHgIA, suggesting that the cytokine changes observed in Daf1 deficiency reflect a response to mercury. The role of Daf1 in influencing cytokine expression was further examined by stimulation of CD4+ T cells in the presence of anti-CD3 and CD97, a molecular partner for Daf1. This resulted in increased IL-10, decreased IL-17 and IL-21 and decreased IFN-,. These findings demonstrate that the absence of Daf1 exacerbates mHgIA, with changes in the profile of expressed cytokines. Interaction between Daf1 and its molecular partner CD97 was found to modify expression of mHgIA-promoting cytokines, suggesting a possible approach for the suppression of overaggressive cytokine production in autoimmunity. [source] Effect of mucosal and systemic immunization with virus-like particles of severe acute respiratory syndrome coronavirus in miceIMMUNOLOGY, Issue 2 2010Baojing Lu Summary Nasal administration has emerged as a promising and attractive route for vaccination, especially for the prophylaxis of respiratory diseases. Our previous studies have shown that severe acute respiratory syndrome coronavirus (SARS-CoV) virus-like particles (VLPs) can be assembled using a recombinant baculovirus (rBV) expression system and such VLPs induce specific humoral and cellular immune responses in mice after subcutaneous injection. Here, we investigated mucosal immune responses to SARS-CoV VLPs in a mouse model. Mice were immunized in parallel, intraperitoneally or intranasally, with VLPs alone or with VLPs plus cytosine,phosphate,guanosine (CpG). Immune responses, including the production of SARS-CoV-specific serum immunoglobulin G (IgG) and secretory immunoglobulin A (sIgA), were determined in mucosal secretions and tissues. Both immunizations induced SARS-CoV-specific IgG, although the levels of IgG in groups immunized via the intraperitoneal (i.p.) route were higher. sIgA was detected in saliva in groups immunized intranasally but not in groups immunized intraperitoneally. CpG had an adjuvant effect on IgA production in genital tract washes when administered intranasally but only affected IgA production in faeces samples when administered intraperitoneally. In addition, IgA was also detected in mucosal tissues from the lung and intestine, while CpG induced an increased level of IgA in the intestine. Most importantly, neutralization antibodies were detected in sera after i.p. and intranasal (i.n.) immunizations. Secretions in genital tract washes from the i.n. group also showed neutralization activity. Furthermore, VLPs that were administered intraperitoneally elicited cellular immune responses as demonstrated by enzyme-linked immunospot (ELISPOT) assay analyses. In summary, our study indicates that mucosal immunization with rBV SARS-CoV VLPs represent an effective means for eliciting protective systemic and mucosal immune responses against SARS-CoV, providing important information for vaccine design. [source] The hinge region fragment of immunoglobulin G improves immunogenicity of recombinant gonadotrophin-releasing hormone conjugated to the T-helper epitope in designing peptide vaccinesIMMUNOLOGY, Issue 1pt2 2009Jinshu Xu Summary In our previous study, the hinge fragment (225,232/225,,232,) of human immunoglobulin G1 (IgG1) was used as a space peptide linker for synthesizing the GnRH3,hinge,MVP chimeric peptide, whereby three repeated gonadotrophin-releasing hormone (GnRH) units and a T-cell epitope from measles virus fusion protein (MVP) were amide-bond-linked at the N and C terminus, respectively, to the hinge peptide for producing anti-GnRH antibody responses. To investigate whether or not the hinge region fragment can improve the immunogenicity of GnRH, we further synthesized and purified GnRH3,hinge,MVP, GnRH3,hinge and GnRH3,MVP using recombinant DNA technology. Under high pH conditions, GnRH3,hinge,MVP was capable of forming double-chain structures. Immunization of male mice with the immunogens of GnRH3,hinge,MVP resulted in the generation of high-titre antibodies specific for GnRH. The synthetic GnRH3,hinge and GnRH3,MVP induced a lower titre of anti-GnRH antibody than GnRH3,hinge,MVP. This was followed by a decrease in serum testosterone levels, which resulted in a low level of expression of the relaxin-like factor gene in the testis. Our data suggest that peptide and T-cell epitopes oriented at the N-terminus or C-terminus of hinge peptides simplify the antigenic peptide conjugates and may be considered as potential synthetic immunogens. [source] Effect of immune serum and role of individual Fc, receptors on the intracellular distribution and survival of Salmonella enterica serovar Typhimurium in murine macrophagesIMMUNOLOGY, Issue 2 2006Hazel Uppington Summary Immune serum has a protective role against Salmonella infections in mice, domestic animals and humans. In this study, the effect of antibody on the interaction between murine macrophages and S. enterica serovar Typhimurium was examined. Detailed analysis at the single-cell level demonstrated that opsonization of the bacteria with immune serum enhanced bacterial uptake and altered bacterial distribution within individual phagocytic cells. Using gene-targeted mice deficient in individual Fc gamma receptors it was shown that immune serum enhanced bacterial internalization by macrophages via the high-affinity immunoglobulin G (IgG) receptor, Fc gamma receptor I. Exposure of murine macrophages to S. enterica serovar Typhimurium opsonized with immune serum resulted in increased production of superoxide, leading to enhanced antibacterial functions of the infected cells. However, opsonization of bacteria with immune serum did not increase either nitric oxide production in response to S. enterica serovar Typhimurium or fusion of phagosomes with lysosomes. [source] A variable number of tandem repeats polymorphism influences the transcriptional activity of the neonatal Fc receptor ,-chain promoterIMMUNOLOGY, Issue 1 2006Ulrich J. H. Sachs Summary The neonatal Fc receptor, FcRn, plays a central role in immunoglobulin G (IgG) transport across placental barriers. Genetic variations of FcRn-dependent transport across the placenta may influence antibody-mediated pathologies of the fetus and the newborn. Sequencing analysis of 20 unrelated individuals demonstrated no missense mutation within the five exons of the FcRn gene. However, a variable number of tandem repeats (VNTR) region within the FcRn promoter was observed, consisting of five different alleles (VNTR1,VNTR5). Alleles with two (VNTR2) and three (VNTR3) repeats were found to be most common in Caucasians (7·5 and 92·0%, respectively). Real-time polymerase chain reaction revealed that monocytes from VNTR3 homozygous individuals express 1·66-fold more FcRn transcript than do monocytes from VNTR2/VNTR3 heterozygous individuals (P = 0·002). In reporter plasmid assays, the VNTR3 allele supported the transcription of a reporter gene twice as effectively as did the VNTR2 allele (P = 0·003). Finally, under acidic conditions, monocytes from VNTR3 homozygous individuals showed an increased binding to polyvalent human IgG when compared with monocytes from VNTR2/VNTR3 heterozygous individuals (P = 0·021). These data indicate that a VNTR promoter polymorphism influences the expression of the FcRn receptor, leading to different IgG-binding capacities. [source] Characterization of cells of the B lineage in the human adult greater omentumIMMUNOLOGY, Issue 1 2006Laurent Boursier Summary Peritoneal B cells and their omental precursors play an important role in the immune response of the peritoneal cavity and mucosal surfaces in mice. We have previously shown that peritoneal and mucosal B lineage cells are unlikely to be significantly linked in humans. However, the status of the omentum remains unknown. Here, using immunohistochemistry, we observed that sparse, quiescent B cells and occasional clusters of B cells were present in the omentum and that plasma cells, predominantly with cytoplasmic immunoglobulin G (IgG), were present. We analysed sequences of immunoglobulin genes amplified using reverse transcriptase,polymerase chain reaction (RT-PCR) from the normal human greater omentum, and describe the characteristics of variable region genes used by IgG, IgA and IgM. We focused on the properties of IgVH4 and IgVH5 families to allow comparisons of like with like between different Ig isotypes and cells from different immune compartments. We observed that the IgM genes were derived from a mixed population with mutated and unmutated immunoglobulin sequences. All IgVH4 and IgVH5 genes used by IgA and IgG from omental cells showed evidence of somatic hypermutation but the load of mutations was not significantly different to that seen in either the systemic or the mucosal compartments. The trends observed, including the dominance of IgG plasma cells, the IgA1/IgA2 ratio being biased towards IgA1, JH1 usage, and a moderate level of somatic mutations, link omental B lineage cells with the systemic compartment. These observations reinforce previous studies highlighting the difference between human and murine B-cell compartments and their relationship to the mucosal immune system. [source] Non-functional immunoglobulin G transcripts in a case of hyper-immunoglobulin M syndrome similar to type 4IMMUNOLOGY, Issue 2 2004John M. Darlow Summary 86% of immunoglobulin G (IgG) heavy-chain gene transcripts were found to be non-functional in the peripheral blood B cells of a patient initially diagnosed with common variable immunodeficiency, who later developed raised IgM, whereas no non-functionally rearranged transcripts were found in the cells of seven healthy control subjects. All the patient's IgM heavy-chain and , light-chain transcripts were functional, suggesting that either non-functional rearrangements were being selectively class-switched to IgG, or that receptor editing was rendering genes non-functional after class-switching. The functional ,-chain sequences showed a normal rate of somatic hypermutation while non-functional sequences contained few somatic mutations, suggesting that most came from cells that had no functional gene and therefore were not receiving signals for hypermutation. However, apoptosis of peripheral blood lymphocytes was not impaired. No defects have been found in any of the genes currently known to be responsible for hyper-IgM syndrome but the phenotype fits best to type 4. [source] Retinoid- and carotenoid-enriched diets influence the ontogenesis of the immune system in miceIMMUNOLOGY, Issue 2 2003Ada L. Garcia Summary Vitamin A (VA) has been identified as an important factor for the development of the immune system, especially during ontogenesis. It has been shown that antibody secretion and proliferation of lymphocyte populations depend on retinoids. In the present study we investigated the influence of a base VA diet and diets enriched with VA, ,-carotene and lycopene, on the ontogenesis of the immune system in mice. We examined the absolute and relative concentrations of splenic B lymphocytes (CD45R/B220), T lymphocytes (CD3+) and their subpopulations (CD4+ and CD8+), and measured serum immunoglobulin G (IgG) concentrations in the offspring of supplemented dams at different ages (1, 3, 5, 7, 14, 21 and 65 days). The experimental diets resulted in higher numbers of T and B lymphocytes after VA and carotenoid enrichment, when compared, at various time-points, with the base diet. Higher values of total serum IgG were found in the ,-carotene-enriched diet group on day 7. On days 7 and 14, the enriched diets induced significant alterations in the percentages and total numbers of splenic lymphocytes in comparison to the base diet. Our results confirm that supplementation with VA and carotenoids affect the immune-cell function during ontogenesis and suggest a possible role of these nutritional factors on the development of the immune system. [source] Induction of a protective capsular polysaccharide antibody response to a multiepitope DNA vaccine encoding a peptide mimic of meningococcal serogroup C capsular polysaccharideIMMUNOLOGY, Issue 2 2003Deborah M. Prinz Summary Systemic infection by encapsulated organisms, such as Neisseria meningitidis, is a major cause of morbidity and mortality worldwide, especially in individuals less than 2 years of age. Antibodies directed at the capsular polysaccharide are shown to be protective against disease by inducing complement-dependent bactericidal activity. The current polysaccharide vaccine has been shown to be poorly immunogenic in high-risk groups and this is probably related to its T-independent properties. An alternative approach to eliciting a T-dependent serum immunoglobulin G (IgG) antibody response to encapsulated pathogens is DNA vaccination. We assessed the immunogenicity of a multiepitope DNA vaccine encoding a T-cell helper epitope and a peptide mimic of N. meningitidis serogroup C. The DNA construct induced a significant anti-polysaccharide antibody response that was bactericidal. Mice immunized with the DNA construct were subsequently protected against challenge with a lethal dose of N. meningitidis serogroup C. [source] | ||||||||||||||||||||||||||||||||||||||||||||||