Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024141 (systemic lupus erythematosus)
 44,322 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have studied the conditions of in vitro binding of platelet glycoprotein IIb/IIIa (GPIIb/IIIa) to fibrinogen and applied the results to identify and measure the serum inhibitors to the binding. For the enzyme-linked immunosorbent assay, platelet extract was delivered to a fibrinogen-coated microtiter plate that was incubated for 2 hours, followed by incubation with anti-GPIIb/IIIa monoclonal antibody for another 2 hours. The plate was then incubated with peroxidase-conjugated anti-mouse IgG for color development. The binding was shown to be calcium-dependent. The binding was partially blocked by treating the coated fibrinogen with anti-fibrinogen antibody. Reduction or dissociation of GPIIb/IIIa resulted in the total loss of its ability to bind to fibrinogen. Platelet extracts of patients with hemophilia showed decreased binding (25% and 14%, compared with control platelet extract), and an extract from a patient with Glanzmann's thrombasthenia showed no binding. With the enzyme-linked immunosorbent assay we have measured serum inhibitors to GPIIb/IIIa binding to fibrinogen in 35 hemophilia A, 17 immune thrombocytopenic purpura, 22 human immunodeficiency virus-related immune thrombocytopenic purpura, and 29 systemic lupus erythematosus serum samples. In those patients with inhibition by serum, polyethylene glycol precipitation of circulating immune complexes (CICs) decreased the inhibition by the supernatants, and all the resolubilized CIC precipitates demonstrated inhibition, which indicates that CICs play a major role in the inhibition of GPIIb/IIIa binding to fibrinogen. This, then, provides evidence of CIC-mediated impaired GPIIb/IIIa binding to fibrinogen in hemophilia A, HIV-ITP, and SLE.
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PMID:Inhibition of platelet GPIIb/IIIa binding to fibrinogen by serum factors: studies of circulating immune complexes and platelet antibodies in patients with hemophilia, immune thrombocytopenic purpura, human immunodeficiency virus-related immune thrombocytopenic purpura, and systemic lupus erythematosus. 200 77

C and CR1 have been shown to participate in the clearance of injected, preformed, immune complexes in humans and in non-human primates. Their role in the physiologic disposal of immune complexes formed in vivo in humans was investigated in three patients receiving radioimmunotherapy for ovarian carcinoma. On day 0 each patient received, by intraperitoneal injection, 10 mg of 131I-mouse anti-tumor mAb (10 mCi/mg). On days 1 and 2, 18 mg of trace-labeled, 125I-human anti-mouse IgG was administered by i.v. infusion over 15 min, to accelerate the clearance of the 131I-anti-tumor antibody from the circulation and reduce the radiation dose to the marrow. Sequential blood samples were obtained after the injection of the second (anti-mouse) antibody, to monitor clearance. Immune complexes (shown by sucrose gradient centrifugation to be 19 to 40 S in size) formed within 5 min, and were cleared with a half-life of 11 +/- 1.7 min in the liver. Complexes were measured by 4% polyethylene glycol precipitation, and by solid phase C3d- and C1q-binding assays. Between 8 and 11% of the total available complexed material bound to CR1 on E. Peak binding of immune complexes to red cells occurred 10 min after the maximal complex load was detected by precipitation with polyethylene glycol. At that time, immune complexes bound to E constituted one-fifth of the total circulating pool of complexes. Coincident with immune complex formation and clearance, a 47% fall in serum C4, C3, and CH50 was measured, with the deposition of up to 1230 molecules of C4, and 2590 molecules of C3 on the surface of red cells. During 20 min after immune complex formation there was a mean loss of 32% of erythrocyte CR1. The changes in complement and CR1 on E and in serum observed in these patients resembled those seen in patients with SLE: i.e., a reduction in CR1 and an increase in C3 and C4 on E, and reduced serum C.
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PMID:A study of in vivo immune complex formation and clearance in man. 214 Oct 40

In this paper we will briefly compare four assays in use in our institute for the measurement of antibodies to DNA: the anti-DNA ELISA, the PEG assay, the indirect immunofluorescence test on Crithidia luciliae and the Farr assay. Although with the use of sera from defined patients with systemic lupus erythematosus (SLE) quite good correlations were obtained between the various assays, these correlations were lost upon the use in routine screening of sera of undefined patients. It will be shown that the Farr assay has the highest specificity to systemic lupus erythematosus, whereas the ELISA and the PEG assay are the most sensitive methods. In its present form, however, the ELISA is not suited for the detection of IgM anti-DNA. Furthermore, this technique alone also detects DNA/-anti-DNA complexes present in sera or hybridoma culture supernatants.
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PMID:A comparison of assays used for the detection of antibodies to DNA. 220 95

A polyethylene glycol (PEG) precipitation F(ab')2 anti-C3 ELISA for the detection of complement-fixing IgG circulating immune complexes (CIC) is described. For this assay, test sera were treated with 3.5% PEG and then measured with F(ab')2 anti-C3 ELISA. The lower detection limit was 4 micrograms/ml of heat aggregated human IgG (HAHG). Intra-assay coefficient of variation (CV) was 4.9-8.3%. High levels of CIC are found in the sera of patients with systemic lupus erythematosus (SLE), hepatitis B and stomach cancer.
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PMID:Detection of circulating immune complexes with polyethylene glycol precipitation F(ab')2 anti-C3 ELISA. 227 58

A human DNA-binding monoclonal antibody was produced by fusing the hepatocytes from a 12-week-old human fetus with the lymphoblastoid cell line GM 4672 using polyethylene glycol. This antibody, designated BEG 2, binds to single-stranded (ss) DNA but also binds to double-stranded (ds) DNA, poly(dT), polyI and poly(ADP-ribose), but not to RNA, cardiolipin or K-30. The binding of BEG 2 to these polynucleotides can be inhibited by incubation with polynucleotides in the fluid phase. A rabbit polyclonal anti-idiotype was raised, and using this reagent it was shown that the BEG 2 idiotype is present in normal human serum (7%), systemic lupus erythematosus (SLE) sera (8%) and rheumatoid arthritis sera (23%). The extent of idiotypic sharing between BEG 2 and murine monoclonal DNA-binding antibodies, in particular monoclonal antibody (mAb) 423 (derived from a 15-day-old fetal MRL/Mp-lpr/lpr mouse) and mAb 402 (derived from an adult MRL/lpr mouse), was also investigated. Using a competition ELISA, it was shown that preincubation of BEG 2 with rabbit anti-423 and rabbit anti-402 inhibits the binding of BEG 2 to DNA, and the binding of 402 to DNA by anti-BEG 2 and anti-423. These data suggest that mAb BEG 2, 423 and 402 share common idiotypes, that autoreactivity is present in early fetal life, and that autoantibodies may be encoded for by germline genes, which have been conserved through evolution.
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PMID:A human fetal monoclonal DNA-binding antibody shares idiotypes with fetal and adult murine monoclonal DNA-binding antibodies. 231 59

In 40 patients with various autoimmune diseases antibodies against desoxyribonucleoprotein (DNP) were assessed by enzyme immunoanalysis (ELISA) in serum and after dissociation of the isolated precipitate of circulating immune complexes (CIC) in the presence of polyethylene glycol. The results indicate that antibodies against DNP are not specific for systemic lupus erythematosus (SLE) and can be detected in serum and in particular in CIC in various autoimmune conditions. In SLE they may be important for evaluation of the activity of the disease, in particular if estimated concurrently in serum and in CIC.
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PMID:[Antibodies against deoxyribonucleoproteins in circulating immune complexes in the blood of patients with autoimmune diseases]. 235 91

Hybridomas producing monoclonal antibodies to DNA were prepared from NZB/W F1 (n = 20), MRL/lpr (n = 13), mice with a chronical graft versus-host-disease (GVHD) (n = 8) and polyclonally stimulated mice (n = 9). Screening was performed by means of an anti-DNA ELISA. Reaction patterns in four different anti-DNA assays (anti-DNA ELISA, indirect immunofluorescence on Crithidia luciliae, PEG assay and Farr assay) as well as avidity and cross-reactivity of these monoclonals were studied in relation to anti-DNA (sub)class and murine origin of the clones. It was found that monoclonal anti-DNA derived from mice with chronic GVHD did not differ from monoclonal anti-DNA derived from NZB/W F1 or MRL/lpr mice, with respect to isotype distribution, avidity towards DNA, cross-reactivity and assay behaviour in the anti-DNA assays mentioned before. In contrast, monoclonal anti-DNA obtained from polyclonally stimulated mice were all of the IgM isotype and displayed a stronger cross-reactive behaviour than the other three models. Altogether, these results exclude the possibility that anti-DNA in the GVHD mice originates from the non-specific pool of natural autoantibodies and further emphasize the relevance of chronic GVHD as a murine model of systemic lupus erythematosus.
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PMID:Murine monoclonal antibodies to DNA. A comparison of MRL/lpr NZB/W and chronically graft-versus-host-diseased mice. 235 56

The authors describe the results of the use of hemosorption in combined treatment of 42 patients with rheumatic diseases. The main group comprised patients with thromboangitis obliterans (23), nonspecific aortoarteritis was recognized in 6 cases, systemic scleroderma and systemic lupus erythematosus in 4, nodular periarteritis in 2. The functional skin tests were made with the aid of the KDU-3 unit, the level of the peripheral blood flow was measured with tetrapolar rheography and impedometry. The degree of redox processes and oxygen tension in the tissues was studied by the polarographic technique, the character of microcirculatory processes with the aid of biomicroscopy of the eyeball conjunctiva, the intensity of immunologic shifts by means of precipitation with polyethylene glycol at different dilutions. In addition, alterations in cellular and serum enzymes were also examined. The data obtained suggest that hemosorption is one of the effective additional methods of the treatment of patients with rheumatic diseases.
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PMID:[Hemosorption in the complex treatment of rheumatic diseases]. 241 73

In recent years defective function of the complement-mediated clearance of immune complexes (IC) has been reported in patients with immune complex disease. The defect has been found at different levels in the clearance system. An important event in this sequential system is the binding of C3-coated particles to C3 receptors on erythrocytes and phagocytes. This study focuses on immunochemical properties of IC-bound C3 that reflect the functional state of the molecule. Sera from patients with primary biliary cirrhosis (PBC), rheumatoid arthritis (RA), and systemic lupus erythematosus (SLE) and from normal subjects were analyzed for their level of C3 precipitable in 2.7% (w/v) polyethylene glycol (PEG). The mean levels for the patient categories were significantly higher than that for the normal subjects. The immunochemical study revealed several differences among the different forms of PEG-precipitable C3. All forms expressed C3(D) antigens which are expressed by immune complex-associated and denatured forms but not by soluble physiological forms of C3. The expression of these antigens was proportionately lower for the complex-associated C3 of PBC compared to that of RA and SLE. Furthermore, employing monoclonal anti-C3(D) antibodies against the C3c and the C3d domain, distinct differences could be detected among all forms of PEG-precipitable C3. Sera from RA and SLE, in particular, contained PEG-precipitable C3 that exhibited distinctive immunochemical features with respect to these epitopes.
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PMID:Quantitation and antigenic characterization of bound C3 of circulating immune complexes in systemic lupus erythematosus, rheumatoid arthritis, and primary biliary cirrhosis. 244 29

Starting with spleen cells from MRL/lpr, NZB/W, and graft-vs-host-diseased mice, we prepared a total of 57 hybridomas that produce antibodies to DNA. Using various approaches, we studied the avidity of these monoclonals in relation to their behavior in four anti-DNA assays. From the results obtained, we postulate that on the basis of anti-DNA avidity the anti-DNA ELISA, the polyethylene glycol assay, the indirect immunofluorescence test on Crithidia luciliae, and the Farr assay (in this order) detect a decreasing amount of anti-dsDNA, the Farr assay being strictly selective for high avidity anti-dsDNA. mAb selected by the anti-DNA ELISA generally were of a low avidity toward DNA. Using cardiolipin and dextran sulfate, a polyanion that bears a resemblance in charge to DNA, we studied the cross-reactivity of the monoclonals. A total of 6 of the 57 monoclonals were found to cross-react with cardiolipin, and 26 with dextran sulfate. We observed an inverse relationship between anti-DNA avidity and cross-reactivity: the lower the avidity of the antibody, the more cross-reactive it is. Based on these findings, we postulate that it is at least questionable whether low avidity, cross-reactive (monoclonal) anti-DNA is representative for the anti-DNA found in patients with SLE.
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PMID:Reaction patterns of monoclonal antibodies to DNA. 245 55


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