Millipore Sigma Vibrant Logo
 

mouse monoclonal anti-phospho-ATM IgG


243 Results Advanced Search  
Showing
Products (29)
Documents (204)
Site Content (10)

Narrow Your Results Use the filters below to refine your search

Document Type

  • (109)
  • (95)
Can't Find What You're Looking For?
Contact Customer Service

 

  • Immunoglobulin G (IgG) attenuates neuroinflammation and improves neurobehavioral recovery after cervical spinal cord injury. 22998664

    Evidence suggests that the inflammatory events in the acute phase of spinal cord injury (SCI) exacerbate the initial trauma to the cord leading to poor functional recovery. As a result, minimizing the detrimental aspects of the inflammatory response after SCI is a promising treatment strategy. In this regard, immunoglobulin G (IgG) from pooled human serum is a promising treatment candidate. Due to its putative, though poorly characterized immuno-modulatory effects, IgG has been used clinically to treat neuroinflammatory disorders such as Guillain-Barré syndrome, but its effects in neurotrauma remain largely unexplored.This study examines the potential neuroprotective effects of IgG in a well-characterized cervical model of SCI. Female Wistar rats were subject to moderate-severe clip compression injury at the C7-T1 level. IgG (0.4 g/kg) or saline was injected intravenously to randomly selected animals at 15 min post SCI. At several time points post SCI, biochemical assays, histology and immunohistochemistry analyses, and neurobehavioral assessments were used to examine the neuroprotective effects of IgG at the molecular, cellular, and neurobehavioral levels.We found that intravenous treatment of IgG following acute clip-compression SCI at C7-T1 significantly reduced two important inflammatory cytokines: interleukin (IL)-1β and IL-6. This early reduction in pro-inflammatory signaling was associated with significant reductions in neutrophils in the spinal cord and reductions in the expression of myeloperoxidase and matrix metalloproteinase-9 in the injured spinal cord at 24 h after SCI. These beneficial effects of IgG were associated with enhanced tissue preservation, improved neurobehavioral recovery as measured by the BBB and inclined plane tests, and enhanced electrophysiological evidence of central axonal conduction as determined by motor-evoked potentials.The findings from this study indicate that IgG is a novel immuno-modulatory therapy which shows promise as a potential treatment for SCI.
    Document Type:
    Reference
    Product Catalog Number:
    Multiple
    Product Catalog Name:
    Multiple

  • Immunoglobulin G locus events in soft tissue sarcoma cell lines. 21731691

    Recently immunoglobulins (Igs) have been found to be expressed by cells other than B lymphocytes, including various human carcinoma cells. Sarcomas are derived from mesenchyme, and the knowledge about the occurrence of Ig production in sarcoma cells is very limited. Here we investigated the phenomenon of immunoglobulin G (IgG) expression and its molecular basis in 3 sarcoma cell lines. The mRNA transcripts of IgG heavy chain and kappa light chain were detected by RT-PCR. In addition, the expression of IgG proteins was confirmed by Western blot and immunofluorescence. Immuno-electron microscopy localized IgG to the cell membrane and rough endoplasmic reticulum. The essential enzymes required for gene rearrangement and class switch recombination, and IgG germ-line transcripts were also identified in these sarcoma cells. Chromatin immunoprecipitation results demonstrated histone H3 acetylation of both the recombination activating gene and Ig heavy chain regulatory elements. Collectively, these results confirmed IgG expression in sarcoma cells, the mechanism of which is very similar to that regulating IgG expression in B lymphocytes.
    Document Type:
    Reference
    Product Catalog Number:
    06-599
    Product Catalog Name:
    Anti-acetyl-Histone H3 Antibody

  • In vivo and in vitro specificity of protein tyrosine kinases for immunoglobulin G receptor (FcgammaRII) phosphorylation. 8756631

    Human B cells express four immunoglobulin G receptors, FcgammaRIIa, FcgammaRIIb1, FcgammaRIIb2, and FcgammaRIIc. Coligation of either FcgammaRII isoform with the B-cell antigen receptor (BCR) results in the abrogation of B-cell activation, but only the FcgammaRIIa/c and FcgammaIIb1 isoforms become phosphorylated. To identify the FcgammaRII-phosphorylating protein tyrosine kinase (PTK), we used the combination of an in vitro and an in vivo approach. In an in vitro assay using recombinant cytoplasmic tails of the different FcgammaRII isoforms as well as tyrosine exchange mutants, we show that each of the BCR-associated PTKs (Lyn, Blk, Fyn, and Syk) shows different phosphorylation patterns with regard to the different FcgammaR isoforms and point mutants. While each PTK phosphorylated FcgammaRIIa/c, FcgammaRIIb1 was phosphorylated by Lyn and Blk whereas FcgammaRIIb2 became phosphorylated only by Blk. Mutants lacking both tyrosine residues of the immune receptor tyrosine-based activation motif (ITAM) of FcgammaRIIa/c were not phosphorylated by Blk and Fyn, while Lyn-mediated phosphorylation was dependent on the presence of the C-terminal tyrosine of the ITAM. Results obtained in assays using an FcgammaR- B-cell line transfected with wild-type or mutated FcgammaRIIa demonstrated that exchange of the C-terminal tyrosine of the ITAM of FcgammaRIIa/c was sufficient to abolish FcgammaRIIa/c phosphorylation in B cells. Additionally, we could show that Lyn and Fyn bind to FcgammaRIIa/c, with the ITAM being necessary for association. Comparison of the phosphorylation pattern of each PTK observed in vitro with the phosphorylation pattern observed in vivo suggests that Lyn is the most likely candidate for FcgammaRIIa/c and FcgammaRIIb1 phosphorylation in vivo.
    Document Type:
    Reference
    Product Catalog Number:
    06-833

  • Oligodendrocytes are damaged by neuromyelitis optica immunoglobulin G via astrocyte injury. 20688809

    Devic's neuromyelitis optica is an inflammatory demyelinating disorder normally restricted to the optic nerves and spinal cord. Since the identification of a specific autoantibody directed against aquaporin 4, neuromyelitis optica-immunoglobulin G/aquaporin 4 antibody, neuromyelitis optica has been considered an entity distinct from multiple sclerosis. Recent findings indicate that the neuromyelitis optica-immunoglobulin G/aquaporin 4 antibody has a pathogenic role through complement-dependent astrocyte toxicity. However, the link with demyelination remains elusive. Autoantibodies can act as receptor agonists/antagonists or alter antigen density in their target cells. We hypothesized that the neuromyelitis optica-immunoglobulin G/aquaporin 4 antibody impairs astrocytic function and secondarily leads to demyelination. Rat astrocytes and oligodendrocytes from primary cultures and rat optic nerves were exposed long-term (24 h) to immunoglobulin G in the absence of complement. Immunoglobulin G was purified from the serum of patients with neuromyelitis optica who were either neuromyelitis optica-immunoglobulin G/aquaporin 4 antibody positive or negative, as well as from healthy controls. Flow cytometry analysis showed a reduction of membrane aquaporin 4 and glutamate transporter type 1 on astrocytes following contact with immunoglobulin G purified from neuromyelitis optica-immunoglobulin G/aquaporin 4 antibody positive serum only. The activity of glutamine synthetase, an astrocyte enzyme converting glutamate into glutamine, decreased in parallel, indicating astrocyte dysfunction. Treatment also reduced oligodendrocytic cell processes and approximately 30% oligodendrocytes died. This deleterious effect was confirmed ex vivo; exposed optic nerves showed reduction of myelin basic protein. Immunoglobulin G from neuromyelitis optica-immunoglobulin G/aquaporin 4 antibody seronegative patients and from healthy controls had no similar effect. Neuromyelitis optica-immunoglobulin G/aquaporin 4 antibody did not directly injure oligodendrocytes cultured without astrocytes. A toxic bystander effect of astrocytes damaged by neuromyelitis optica-immunoglobulin G/aquaporin 4 antibody on oligodendrocytes was identified. Progressive accumulation of glutamate in the culture medium of neuromyelitis optica-immunoglobulin G/aquaporin 4-antibody-treated glial cells supported the hypothesis of a glutamate-mediated excitotoxic death of oligodendrocytes in our models. Moreover, co-treatment of glial cultures with neuromyelitis optica-immunoglobulin G/aquaporin 4 antibody and d+2-amino-5-phosphonopentanoic acid, a competitive antagonist at the N-methyl-d-aspartate/glutamate receptor, partially protected oligodendrocytes. Co-immunolabelling of oligodendrocyte markers and neuromyelitis optica-immunoglobulin G/aquaporin 4 antibody showed that astrocytic positive processes were in close contact with oligodendrocytes and myelin in rat optic nerves and spinal cord, but far less so in other parts of the central nervous system. This suggests a bystander effect of neuromyelitis optica-immunoglobulin G-damaged astrocytes on oligodendrocytes in the nervous tissues affected by neuromyelitis optica. In conclusion, in these cell culture models we found a direct, complement-independent effect of neuromyelitis optica-immunoglobulin G/aquaporin 4 antibody on astrocytes, with secondary damage to oligodendrocytes possibly resulting from glutamate-mediated excitotoxicity. These mechanisms could add to the complement-induced damage, particularly the demyelination, seen in vivo.
    Document Type:
    Reference
    Product Catalog Number:
    Multiple
    Product Catalog Name:
    Multiple

  • Monoclonal antibody-based solid-phase immunoenzymometric assays for quantifying human immunoglobulin G and its subclasses in serum. 3905065

    We developed quantitative immunoenzymometric assays for human IgG and its subclasses by using monoclonal antibodies, an avidin-biotin detection system and, as the calibrant, the U.S. National Reference Preparation for Specific Human Proteins. The assays are sensitive (detecting as little as 6 micrograms/L), precise (average inter-assay CV less than 11%), and vary linearly with concentrations over a five- to 10-fold range, depending on the monoclonal antibody. We evaluated 22 different monoclonal antibodies, many of which remained highly reactive when immobilized in wells of microtiter plates coated with bovine serum albumin-glutaraldehyde to "capture" total IgG or subclasses of IgG in the sample. We demonstrated the specificity of the most reactive antibodies by using a panel of 20 purified myeloma proteins. The sum of IgG subclass concentrations correlated well (r = 0.84, p less than 0.001) with the total IgG measured in sera from 63 apparently healthy adults (26 men, 37 women). We estimated 95 percentile reference intervals for the immunoglobulins in these subjects and determined the following mean percentage distributions of IgG subclasses: IgG1 49, IgG2 33, IgG3 9, and IgG4 7. The availability of these assays should facilitate studies of the clinical significance of the subclasses.
    Document Type:
    Reference
    Product Catalog Number:
    Multiple
    Product Catalog Name:
    Multiple

  • Treatment response in Kawasaki disease is associated with sialylation levels of endogenous but not therapeutic intravenous immunoglobulin G. 24324693

    Although intravenous immunoglobulin (IVIG) is highly effective in Kawasaki disease (KD), mechanisms are not understood and 10-20% of patients are treatment-resistant, manifesting a higher rate of coronary artery aneurysms. Murine models suggest that α2-6-linked sialic acid (α2-6Sia) content of IVIG is critical for suppressing inflammation. However, pro-inflammatory states also up-regulate endogenous levels of β-galactoside:α2-6 sialyltransferase-I (ST6Gal-I), the enzyme that catalyzes addition of α2-6Sias to N-glycans. We asked whether IVIG failures correlated with levels of α2-6Sia on infused IVIG or on the patient's own endogenous IgG.We quantified levels of α2-6Sia in infused IVIG and endogenous IgG from 10 IVIG-responsive and 10 resistant KD subjects using multiple approaches. Transcript levels of ST6GAL1, in patient whole blood and B cell lines were evaluated by RT-PCR. Plasma soluble (s)ST6Gal-I levels were measured by ELISA.There was no consistent difference in median sialylation levels of infused IVIG between groups. However, α2-6Sia levels in endogenous IgG, ST6GAL1 transcript levels, and ST6Gal-I protein in serum from IVIG-resistant KD subjects were lower than in responsive subjects at both pre-treatment and one-year time points (p less than 0.001, respectively).Our data indicate sialylation levels of therapeutic IVIG are unrelated to treatment response in KD. Rather, lower sialylation of endogenous IgG and lower blood levels of ST6GALI mRNA and ST6Gal-I enzyme predict therapy resistance. These differences were stable over time, suggesting a genetic basis. Because IVIG-resistance increases risk of coronary artery aneurysms, our findings have important implications for the identification and treatment of such individuals.
    Document Type:
    Reference
    Product Catalog Number:
    MAB1304
    Product Catalog Name:
    Mouse Anti-Human IgG Antibody, Fd, clone HP6045

  • 192 immunoglobulin G-saporin produces graded behavioral and biochemical changes accompanying the loss of cholinergic neurons of the basal forebrain and cerebellar Purkinj ... 7777161

    Immunolesions of the cholinergic basal forebrain were produced in rats using various intraventricular doses of the immunotoxin 192 immunoglobulin G-saporin: 0.34, 1.34, 2.0, 2.7 and 4.0 micrograms/rat. A battery of behavioral tests, chosen on the basis of reported sensitivity to conventional medial septal or nucleus basalis lesions, was administered. Dose-dependent impairments were found in acquisition, spatial acuity and working memory in the water maze. Dose-dependent hyperactivity in the open field and in swimming speed was observed. The highest dose group (4.0 micrograms) exhibited motoric disturbances which were particularly apparent in swimming and in clinging to an inclined screen. Response and habituation to acoustic startle were diminished in the three higher dose groups. Histological results from acetylcholinesterase and low-affinity nerve growth factor receptor staining showed that the lesion was selective for cholinergic neurons bearing p75 nerve growth factor receptors in the basal forebrain nuclei. However, some Purkinje cells in the superficial layers of the cerebellum were also destroyed at the higher doses of immunotoxin. The activity of choline acetyltransferase, used as a marker of cholinergic deafferentation in regions innervated by the basal forebrain nuclei, was decreased with increasing doses to a plateau level of about 90% (average depletion) for the two highest dose groups. These two groups were the only ones to exhibit consistent and severe behavioral impairments on all behavioral tests performed. Thus, for a relatively selective cholinergic basal forebrain lesion, almost a 90% reduction in choline acetyltransferase activity is needed to produce substantial behavioral deficits. It appears that either a considerable safety factor exists or robust compensatory mechanisms can ameliorate behavioral deficits from a major, but incomplete loss of cholinergic basal forebrain innervation.
    Document Type:
    Reference
    Product Catalog Number:
    Multiple
    Product Catalog Name:
    Multiple

  • The ectodomain of a novel member of the immunoglobulin subfamily related to the poliovirus receptor has the attributes of a bona fide receptor for herpes simplex virus ty ... 9811737

    We report on the functional cloning of a hitherto unknown member of the immunoglobulin (Ig) superfamily selected for its ability to confer susceptibility to herpes simplex virus (HSV) infection on a highly resistant cell line (J1.1-2 cells), derived by exposure of BHKtk- cells to a recombinant HSV-1 expressing tumor necrosis factor alpha (TNF-alpha). The sequence of herpesvirus Ig-like receptor (HIgR) predicts a transmembrane protein with an ectodomain consisting of three cysteine-bracketed domains, one V-like and two C-like. HIgR shares its ectodomain with and appears to be an alternative splice variant of the previously described protein PRR-1 (poliovirus receptor-related protein). Both HIgR and PRR-1 conferred on J1.1-2 cells susceptibility to HSV-1, HSV-2, and bovine herpesvirus 1. The viral ligand of HIgR and PRR-1 is glycoprotein D, a constituent of the virion envelope long known to mediate viral entry into cells through interaction with cellular receptor molecules. Recently, PRR-1, renamed HveC (herpesvirus entry mediator C), and the related PRR-2, renamed HveB, were reported to mediate the entry of HSV-1, HSV-2, and bovine herpesvirus 1, and the homologous poliovirus receptor was reported to mediate the entry of pseudorabies virus (R. J. Geraghty, C. Krummenacher, G. H. Cohen, R. J. Eisenberg, and P. G. Spear, Science 280:1618-1620, 1998; M. S. Warner, R. J. Geraghty, W. M. Martinez, R. I. Montgomery, J. C. Whitbeck, R. Xu, R. J. Eisenberg, G. H. Cohen, and P. G. Spear, Virology 246:179-189, 1998). Here we further show that HIgR or PRR-1 proteins detected by using a monoclonal antibody to PRR-1 are widely distributed among human cell lines susceptible to HSV infection and commonly used for HSV studies. The monoclonal antibody neutralized virion infectivity in cells transfected with HIgR or PRR-1 cDNA, as well as in the human cell lines, indicating a direct interaction of virions with the receptor molecule, and preliminarily mapping this function to the ectodomain of HIgR and PRR-1. Northern blot analysis showed that HIgR or PRR-1 mRNAs were expressed in human tissues, with the highest expression being detected in nervous system samples. HIgR adds a novel member to the cluster of Ig superfamily members able to mediate the entry of alphaherpesviruses into cells. The wide distribution of HIgR or PRR-1 proteins among human cell lines susceptible to HSV infection, coupled with the neutralizing activity of the antibody in the same cells, provides direct demonstration of the actual use of this cluster of molecules as HSV-1 and HSV-2 entry receptors in human cell lines. The high level of expression in samples from nervous system makes the use of these proteins in human tissues very likely. This cluster of molecules may therefore be considered to constitute bona fide receptors for HSV-1 and HSV-2.
    Document Type:
    Reference
    Product Catalog Number:
    MABT61
    Product Catalog Name:
    Anti-Nectin-1/PVRL1 (CD111) Antibody, clone R1.302