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)

A lupus-like syndrome involving chronic urticaria with cutaneous vasculitis, systemic symptoms, hypocomplementemia with preferential depletion of C1q, and low m.w. (7S) C1q-precipitins has recently been defined. The C1q-precipitin activity (C1q-p) seems to represent a diagnostic marker of the disease, but its chemical nature is not yet clear. We have partially purified and characterized C1q-p from the serum of two patients with this syndrome and compared its activity with the C1q-precipitating activity of aggregated human gamma-globulin (AHGG) anti-C1q antibodies, and several polynucleotides including DNA and polyinosinic acid. C1q-p was found to partition with IgG during precipitation by ammonium sulfate and low ionic strength buffer as well as during column chromatography on DEAE-cellulose and G-200 Sephadex. Like AHGG, but in complete contrast to the polynucleotides, the C1q-precipitating activity of C1q-p was sensitive to pepsin, trypsin, and acidic conditions, but unaffected by DNAse or RNAse; the C1q-precipitating activity of anti-C1q antibody was not diminished by any of these procedures. Thus, C1q-p consists of gamma-migrating protein of low m.w., and its C1q-precipitating activity is indistinguishable from that of AHGG. These results are consistent with the concept that C1q-p is comprised, at least in part, of IgG that binds C1q via the Fc portion of the molecule.
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PMID:Low molecular weight C1q-precipitins in hypocomplementemic vasculitis-urticaria syndrome: partial purification and characterization as immunoglobulin. 2 69

The effect of non-specific binding caused by the interaction between gamma-globulin and denatured DNA was markedly reduced by addition of dextran sulfate or CaCl2 at alkaline pH. This method was shown to be applicable in the detection of anti-DNA antibodies in sera from cases of human systemic lupus erythematosus.
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PMID:Reduction of the non-specific binding of DNA to gamma-globulin in Farr radioimmunoassay by addition of dextran sulfate and calcium chloride. 8 42

An anti-membrane antibody was present in the sera of systemic lupus erythematosus patients in immunoelectrosyneresis with sodium dodecyl sulfate (SDS) solubilized erythrocyte membrane as antigen. The SDS bound to protein was detected by chromatography at 10(-3)M concentration under U.V. light, at 10(-5)M concentration by the distilled water spray method and at 10(-6)M concentration by using rosaniline hydrochloride colorimetry. SDS was removed from the membrane protein at a concentration of 10(-3)M by the first gel filtration of Sephadex G-25 column and at a concentration of 10(-6)M by rechromatography of the same column. More than 99% of SDS in the solubilized erythrocyte membrane was removed by gel filtration. The antigenicity was still positive in the refiltrated fractions of systemic lupus erythematosus patients. Therefore, all precipitates in the gels were antigen-antibody aggregates.
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PMID:Effect of sodium dodecyl sulfate on immuno-electrosyneresis between normal human erythrocyte membrane and sera of systemic lupus erythematosus patients. 13 42

Detection of antibody to double-stranded DNA by direct binding assays has proved useful in clinical management of patients with systemic lupus erythematosus (SLE). Recent confusion regarding specificity of these antibodies for SLE appears to be due, at least in part, to contamination of natural DNA preparations with nondouble-stranded DNA antigens. Measurement of binding of a synthetic, self-complementary DNA copolymer (dAT) rather than of natural DNA (KB) has been shown to obviate some of these difficulties, apparently because of freedom of dAT from nondouble-stranded DNA antigens. Among the advantages found in this way was a higher degree of specificity of antibodies to double-stranded DNA for clinically-judged active lupus nephritis than had been suspected. Since activity of nephritis is difficult to assess clinically, histologic data were sought to confirm these observations. Thirty-two kidney specimens were examined by light and/or electron microscopy. The degree of histologic activity and the amount and location of glomerular electron-dense deposits were semiquantitated blindly. The binding of both dAT and KB DNA was measured by the ammonium sulfate method. Correlation with the amount of electron-defense deposits was highly significant for dAT binding and somewhat less so for KB DNA binding as determined by both parametric and nonparametric statistical methods. Significant correlation with histologic activity was found for dAT but not KB DNA binding. These results are consistent with previous data and suggest that dAT binding may provide a useful, noninvasive means of clinically assessing both nephritis activity and the intensity of glomerular immune-complex deposition as reflected by the amount of electron-dense deposits. If it can be confirmed that the latter provides long-term prognostic information, then dAT binding (and perhaps its reponse to therapy) may also prove of value in this regard.
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PMID:Binding of synthetic double-stranded DNA by serum from patients with systemic lupus erythematosus: correlation with renal histology. 13 6

Electrophoresis in polyacrylamide gels in the presence of sodium dodecyl sulfate was used to separate and quantitate the components of a washed immune precipitate. Serum was from patients with systemic lupus erythematosus known to have antibodies to soluble nuclear ribonucleoprotein (RNP) or to a soluble nuclear non-nucleic acid protein (Sm). Amounts of antibody that was predominantly IgG ranged from 0.2 to 8 mg/ml of patients' serum, and in some cases accounted for over 20% of the total serum IgG. Results demonstrate that some patients respond to the disease by producing large amounts of a specific antibody, and that these antibodies can contribute significantly to hypergammaglobulinemia.
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PMID:Quantitation of precipitating antibodies to certain soluble nuclear antigens in SLE. 30 Oct 28

Ten patients with clinically active SLE and biopsy-proven renal involvement were studied. Antigen binding capacity (ABC) and avidity of anti-nDNA antibodies were measured, using 125I-nDNA, by the ammonium sulfate test of Minden and Farr. The glomerular localization of immune complexes was determined by morphological studies. Mean avidity in 7 patients with mesangial and subendothelial deposits was 0.387 +/- 0.022 (mean +/- SE), and in those with additional subepithelial deposits was 0.247 +/- 0.036 (P less than 0.01). When measured serially, the avidity was found to alter slowly either during treatment or spontaneously. Follow-up histology in 2 cases showed morphologic transitions; in one the transition from the initial mesangial proliferative type to the membranous form was associated with a shift of the avidity from a high level to a low one. There was no significant relation between the avidity and ABC (r = 0.235, P greater than 0.1), suggesting that avidity and the quantitative ABC of antibodies in immune complexes may not necessarily behave in parallel. Thus, the avidity measurement is useful in understanding the immunological events which underlie various clinicopathological features of SLE.
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PMID:Avidity of anti-native DNA antibody and glomerular immune complex localization in lupus nephritis. 30 13

Antibodies that bind tRNA are produced spontaneously in New Zealand Black/New Zealand White (NZB/NZW) F1 hybrid female mice. An assay for the detection of these antibodies has been developed by using gel filtration and radioactive tRNA. This assay was found superior to the widely used ammonium sulfate precipitation assay because of the nature of the interaction between the protein and the tRNA. The ant-bodies bound native tRNA preferentially to tRNA denatured by cross-linking with formaldehyde. This conformational specificity was confirmed in competition experiments. The antibodies to native tRNA had an average association constant of 5 x 10(7) leter/mole at 4 degrees C and could bind to more than one site per tRNA molecule. Experiments with immunoglobulin class-specific anti-mouse antisera, in solution and by radioimmunoelectrophoresis, showed that the antibodies were heterogeneous, but were predominantly of the IgG class. These antibodies may be useful for detection, localization, and conformational analysis of tRNA in solution as well as for understanding the pathogenesis of the lupus-like syndrome in these mice.
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PMID:Properties of tRNA-specific antibodies from NZB/NZW mice. 32 80

The 25,000 dalton protein of Mason-Pfizer monkey virus (MPMV) was isolated by gel filtration chromatography. In agreement with results from other laboratories, antisera to type-C and the non-type-C bovine leukemia and equine infectious anemia viruses did not precipitate 125I-labelled MPMV p25. In addition, these viruses did not cross-react in a competition radioimmunoassay for MPMV p25. Twenty-one human tissues (15 breast carcinomas, 2 normal breasts, 3 acute myelogenous leukemias and 1 sarcoma) were fractionated by detergent solubilization, ammonium sulfate precipitation, and DE-52 anion exchange chromatography. These methods were shown to be highly effective for purification of MPMV p25. Under assay conditions which minimized incubation damage to the 125I-MPMV p25, all tissues failed to react in the competition radioimmunoassay (RIAT). Two hundred and two human sera or plasma specimens, including those from patients with breast cancer and 33 age-matched controls, from 50 patients with hematologic malignancies, from 12 patients with amyotrophic lateral sclerosis, and from 14 patients with systemic lupus erythematosis, were examined for antibodies to MPMV p25. With the exception of two multiple myeloma plasma which produced artifactual false positive reactions based on hypergammaglobulinemia, a known complication of salt precipitation radioimmunoassays, the remainder of the specimens were negative for evidence of MPMV p25 antibodies.
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PMID:Radioimmunoassay for the major structural protein of Mason-Pfizer monkey virus: Attempts to detect the presence of antigen or antibody in humans. 40 48

A modification of the enzyme-linked immunosorbent assay (ELISA) is described, that permits determination of antibodies to native DNA (nDNA). The same approach can be used to measure antibodies to denatured DNA (dDNA). Poor binding of nDNA to the polystyrene solid phase has presented difficulties in using the ELISA method for assaying anti-nDNA activity (Engvall, 1976), but we find that precoating of the solid phase with protamine sulfate circumvents this problem. Assays for anti-dDNA are also enhanced by the use of protamine sulfate coated tubes. We have used the ELISA method to assay 15 SLE and 27 non-SLE sera for anti-nDNA and anti-dDNA activity. The results are compared with those obtained using the GF/A glass fiber filter assay, previously described by Lewis et al. (1973).
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PMID:An enzyme-linked immunosorbent assay for antibodies to native and denatured DNA. 47 14

In the course of examining polymorphonuclear leukocyte (PMN) chemotaxis in patients with systemic lupus erythematosus (SLE), we have found a previously undescribed serum inhibitor of complement (C5)-derived chemotactic activity. Serum from a 25-yr-old Black female with untreated SLE, when activated with zymosan, failed completely to attract either her own or normal PMN. Incubation of normal PMN with the patient's serum did not affect their subsequent random motility or chemotactic response toward normal zymosan-treated serum (ZTS). The patient's serum, however, did inhibit the chemotactic activity of normal ZTS and of column-purified C5-derived peptide(s), but had no effect on the chemotactic activity of either the synthetic peptide, N-formylmethionyl leucyl-phenylalanine or a filtrate prepared from a culture of Escherichia coli (bacterial chemotactic factor). The inhibitory activity in the patient's serum resisted heating at 56 degrees C for 30 min and could be separated from C5-derived chemotactic activity in the patient's ZTS (or normal ZTS that had been incubated with the patient's serum) by chromatography on Sephadex G-75. Despite its effect on C5-derived chemotactic activity, the patient's serum did not influence two other C5-derived biologic activities: PMN lysosomal enzyme-releasing activity and PMN-aggregating activity. Chromatography of the patient's serum (65% ammonium sulfate pellet) on Sephadex G-200 yielded three distinct peaks of inhibitory activity. Two were heat labile and exhibited other properties of the previously described chemotactic factor inactivators of normal human serum. The third and most active peak, however, resisted heating at 56 degrees C for 30 min, eluted with an apparent mol wt of 50,000-60,000, and acted specifically on C5-derived chemotactic activity. This uniquely specific, heat-stable inhibitor of C5-derived chemotactic activity has been found thus far in serum from 4 of 11 patients with active SLE and may account, in part, for altered host defenses against infections caused by pyogenic microorganisms.
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PMID:A specific inhibitor of complement (C5)-derived chemotactic activity in serum from patients with systemic lupus erythematosus. 65 35


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