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PubMed1986

Complement C3b receptors on erythrocytes, circulating immune complexes, and complement C3 split products in patients with primary Sjögren's syndrome.

Twenty-one patients with primary Sjögren's syndrome (SS) and 22 age- and sex-matched healthy controls were examined for levels of C3b receptors (CR1) on erythrocytes (by an enzyme-linked immunosorbent assay), levels of circulating immune complexes (IC) (by a polyethylene glycol precipitation complement consumption method), and C3 split products, C3d and C3c (by intermediate gel rocket immunoelectrophoresis). CR1 varied within a wide range (20-124%), and a preponderance of low numbers was found among patients with primary SS (P less than 0.05). The levels of circulating IC and C3d were elevated in primary SS patients (P less than 0.01) and were mutually correlated (P less than 0.01; tau = 0.5), but levels of circulating IC and C3d did not correlate with CR1 values. C3c concentrations were the same in patients and controls. It is possible that the CR1 level serves as a predictor for the development of IC-induced manifestations, and the C3d concentration serves as an objective parameter for disease activity in primary SS.

Adult↗
PubMed1983

Complement activation in shock associated with a surgically provoked bacteriaemia.

The activation of complement (C) factors in a patient exhibiting an anaphylactoid shock 10 min after the initiation of transurethral coagulation of vesical papillomas was studied. Streptococcus faecalis was cultured from he urine before and after the shock and from the blood on two occasions within 2 days after the shock. The shock was associated with a marked but transient complement activation as judged from serial determinations of C3d and C3c by doubledecker rocket immuno electrophoresis and native C3 and C3c by crossed immuno electrophoresis. Conventional total C3 quantitation by rocket immuno electrophoresis did not reveal the activation. A decrease of native C4 to 20% of normal values and the appearance of C4 split products indicated classical pathway activation. Factor B conversion showed the alternative pathway to be involved as well. Total haemolytic complement activity was temporarily reduced, increasing without reaching normal values within 20 hours. The results indicated that the classical pathway was transiently activated, pointing to an acute antigen-antibody reaction, probably caused by the entrance of bacteria and bacterial products into the circulation of an immunized host.

Anaphylaxis↗
PubMed2003

Innate immune system is implicated in recurrent aphthous ulcer pathogenesis.

BACKGROUND: Recurrent aphthous ulcers (RAU) is a chronic inflammatory disease with evidence of inappropriate immune response. This study presents the status of innate immune system in RAU. METHODS: Twenty RAU patients and 19 healthy individuals were selected. The status of peripheral blood neutrophils (reactive oxygen intermediates (ROI) production, CD11b, TNF-RI and TNF-RII expression), concentration of antioxidants, sTNF-R, C3c, C4 and haemolytic activity of the complement system, as well as mannose-binding lectin (MBL), in the serum of RAU patients in active stage and in remission of the disease were determined. RESULTS: Peripheral blood neutrophils were primed in RAU, which resulted in increased ROI production by resting and fMLP-stimulated neutrophils and diminished ROI production after in vitro priming. The increased expression of CD11b on resting and fMLP-stimulated neutrophils in RAU may also point to their previous in vivo stimulation. The decreased total antioxidant status of serum observed in RAU may be a result of increased ROI production by peripheral blood neutrophils. The levels of C3c, C4 and haemolytic activity of the complement system were higher in RAU than in healthy people. No significant differences between active and remission RAU were noted. CONCLUSION: Presented observations confirm that the innate immune system is involved in RAU pathogenesis.

Adolescent↗
PubMed1998

Studies on protein adsorption and activation of complement on hydrated aluminium surfaces in vitro.

Adsorption of human plasma and serum proteins onto hydrated aluminium was studied by ellipsometry/antibody techniques, and soluble complement components iC3b, Bb, and C4d with commercial ELISA plates. Aluminium that was incubated in plasma for 1 min bound significant amounts of anti-lipoproteins (anti-LP), no antibodies against contact activation of coagulation proteins, and no anti-fibrinogen (anti-Fib). Time course studies with serum revealed increasing deposition of anti-C3c with time. Complement factor 1q (C1q) was antibody detectable only after short-time serum incubations, but no anti-IgG and anti-properdin bound to the protein film at any time. Anti-C3c was not deposited after exposure of the surfaces to Clq-depleted serum. Intriguingly, and in spite of increasing deposition of C3 to the surface with time, the combined ellipsometry and ELISA results gave no unequivocal proof of activation of complement by hydrated aluminium.

Adsorption↗
PubMed1997

The value of immunoglobulin and complement levels in the early diagnosis of neonatal sepsis.

Serum IgG, IgG1, G2, G3, G4, IgM, C3c and C4 concentrations were measured in 24 term neonates with sepsis and 17 healthy normal neonates of similar age, sex and weight (control group). The serum IgG, IgG1, G2, G3, G4, IgM, C3c, and C4 levels were similar in the patients with sepsis and the control group (p > 0.05). In the neonates with sepsis, serum IgG, G1, G2, IgM and C4 levels were not significantly different between the 1st and 10th days, while there were significant differences for IgG3, G4 and C3c (p < 0.05). We conclude that the serum levels of IgG, IgG1, G2, G3, G4, IgM, C3c and C4 concentrations are of no value for the early diagnosis of neonatal sepsis.

Bacteremia↗
PubMed1992

[Effect of re-utilization of cuprophan capillary dialysers with different liquids on their biocompatibility and effectiveness of elimination].

In 22 patients cuprophane capillary dialyzers reutilized in turn with four sets of liquids were used four times (Andante type in 13 and TAF-12 in 9 patients). The degree of biocompatibility and efficiency of elimination of small molecules was evaluated. During four-time reuse of dialyzers reutilized with sodium hypochlorite and with formaldehyde a reduction of intra-dialysis leukopenia, granulocytopenia and thrombocytopenia was not stated in blood of the patients. Activation of the complement system measured with the quantity of decrease of C3c fraction of the complement in the patients blood after 20 minutes of dialysis reduced essentially only at the fourth reuse of dialyzers (p < 0.01). Creatinine clearance measured always one hour after starting of the dialysis, did not change in succeeding reuse of dialyzers. Reutilization of dialyzers with hydrogen peroxide solution and formaldehyde caused essential reduction of ++intra-dialysis leukopenia and neutropenia (p < 0.001). There was lack of changes in ++intra-dialysis thrombocytopenia. Activation of the complement system was reduced essentially only after the fourth reuse of dialyzers (p < 0.001), but was also essentially lower (p < 0.05) than with dialyzers reutilized with sodium hypochlorite and with formaldehyde. Creatinine clearance practically did not change and at the fourth reuse of dialyzers it decreased on the average by 1.8%. Reutilization with acetic acid already at the second reuse of dialyzers essential (p < 0.001) and deepened decrease of intradialytic leukopenia and neutropenia and the activation of the complement system in course of succeeding reuses. Intradialytic thrombocytopenia was subjected to vestigal, not essential decrease. Creatinine clearance lowered a little but not essentially. At the fourth reuse of dialyzers it was lower on the average by 3.6% than the initial one. Reutilization with Dialina (stabilized blend of peracetic, acetic acid and hydrogen peroxide solution) caused essential (p < 0.001) and, in course of further reuses, deepening of lowering of intradialytic leukopenia and neutropenia as well as the activation of the complement system already at the second reuse. At the same time at the second and fourth reuse of dialyzers reutilized with Dialina the activation of the complement system was essentially lower than reutilized with the other liquids (p < 0.02). At the fourth reuse intradialytic thrombocytopenia also lowered essentially (p < 0.01). Creatinine clearance lowered a little more than with other liquids and at the second reuse of dialyzers was lower on the average by 5.6%, and at the fourth reuse--by 6.7% in relation to the new dialyzers.(ABSTRACT TRUNCATED AT 400 WORDS)

Acetates↗
PubMed1996

Blood protein interactions with chromium surfaces.

Protein adsorption, contact activation, and complement activation were studied on thin evaporated films of chromium (Cr) in vitro. The surfaces were, prior to the experiments, cleaned in either ethanol and water, or in a basic peroxide solution (RCA standard clean 1, SC-1). Surface spectroscopic studies of the outermost oxides showed a significant reduction of carbon contaminants after washing in SC-1 but also suggested an increase in the oxidation state as compared with the ethanol-washed surfaces. In situ ellipsometry combined with antibody techniques was used to determine protein deposition and antibody binding onto surfaces after incubations in heparin plasma or in normal serum. Incubation times from 1 to 10 min in serum showed increased depositions of serum and antibodies to complement factor 3c (C3c) and was larger on ethanol-washed surfaces than on surfaces washed in SC-1. ELISA methods indicated increased amounts of iC3b in serum for both surfaces, but no presence of C3 convertases (C4d or Bb fractions). A low or transient complement activation via the classical pathway was indicated on ethanol washed Cr, since deposition of secondary antibodies to complement factor Iq (CIq) was observed only after short incubation times in serum. No procoagulant activity of Cr was indicated, since only low amounts of antibodies to factor XII (F XII), prekallikrein (PKK), and high molecular weight kiniogen (HMWK) bound to the surfaces after incubations in heparin plasma. These results were confirmed using a colorimetric assay where the relative amounts of free plasma kallikrein was assessed using a chromogenic substrate, H-D-Pro-Phe-Arg-pNA (S-2302).

Adsorption↗
PubMed1986

In vitro bioassay of erythropoietic activity in serum using mouse spleen cells. The effect of heat inactivation on serum erythropoietin.

Untreated human serum is known to be toxic to in vitro assays for erythropoietin, including the mouse spleen cell assay system (MSCA). This phenomenon had previously been shown to be mediated by complement-dependent IgM heteroantibodies and can be overcome by heating the serum at 56 degrees C for 30 minutes. Using the MSCA, we have found that the toxic effect of serum could also be removed by treatment with a precipitating antibody against the C3c component of complement. The effects of the two methods of complement inactivation on the measurement of stimulatory activity in serum have been compared. For normal serum, the results after heat inactivation and antibody treatment were similar. In contrast, serum from a patient with aplastic anemia gave a result equivalent to 327 mU erythropoietin/ml after heat treatment, but after antibody treatment equivalent to 1,520 mU erythropoietin/ml. Gel permeation chromatography of unheated, heated, and antibody-treated sera showed that heating markedly reduced the activity of the erythropoietin peak. Seventy percent of the activity of partially purified urinary erythropoietin was lost during heating in the presence of normal serum. In addition, heating caused the appearance of high molecular weight compounds that are stimulatory in the MSCA. The level of this activity appeared to be directly related to the stimulatory activity of the unheated serum.

Anemia, Aplastic↗
PubMed2004

BF, HP, DQB and DRB are associated with haemolytic complement activity, acute phase protein reaction and antibody response in the pig.

In order to examine the loci factor B (BF), C3, corticotropin releasing hormone (CRH), DQB, DRB, haptoglobin (HP) and transforming growth factor beta 1 (TGFB1) for association with traits of humoral, specific and unspecific defence F2-animals of a porcine resource family were genotyped at single nucleotide polymorphisms within these loci. Haemolytic complement activity in the alternative and classical pathway, C3c and haptoglobin serum concentration and antibody titres were determined immediately prior and at days 4 and 10 after vaccinations against Mycoplasma hyopneumoniae (Mh), Aujeszky's disease virus, and porcine reproductive and respiratory syndrome virus at 6, 14 and 16 weeks of age, respectively. Analysis of variance revealed association of BF, HP and DRB with C3c serum concentration. The trend of haemolytic complement activity and C3c serum concentration during the experiment was affected by the interaction of DQB genotype and time of measurement. Association with antibody titres were found for BF, DQB and DRB. Results of the mixed model analyses were confirmed by quantitative transmission disequilibrium test that showed linkage and association with antibody titres, complement activity and acute phase reaction at certain times of measurement. The findings promote the importance of the candidate genes for humoral mechanisms of unspecific and specific defence that provide natural resistance against many pathogens.

Acute-Phase Proteins↗
PubMed1997

Effects of psychological stress on serum immunoglobulin, complement and acute phase protein concentrations in normal volunteers.

The aim of this study was to examine the effects of academic examination stress on serum immunoglobulins (Igs), i.e. IgA, IgG, IgM, complement factors, i.e. C3c and C4, and acute phase proteins, i.e. alpha 1-acid glycoprotein (alpha 1-S), haptoglobin (Hp) and alpha 2-macroglobulin (alpha 2-M). Thirty-seven university students participated in this study. Serum was sampled a few weeks before and after as well as one day before a difficult academic examination. On the same occasions, students completed the Perceived Stress Scale (PSS). Students were divided into two groups, i.e. those with high- and low-stress perception as defined by changes in the PSS score. Academic examination stress induced significant increases in serum IgA, IgG, IgM, and alpha 2-M in students with high-stress perception, but not in these with low-stress perception. The stress-induced changes in serum IgA, C3c, and alpha 1-S concentrations were significantly higher in students with high-stress perception than in those with a low-stress perception. The stress-induced changes in serum IgA, IgM, C3c, C4, alpha 1-S, Hp and alpha 2-M were normalized a few weeks after the stress condition, whereas IgG showed a trend toward normalization. There were significant positive relationships between the stress-induced changes in the PSS and serum IgA, IgG, IgM and alpha 2-M. These findings suggest that psychological stress is accompanied by an altered secretion of serum Igs, complement factors and some acute phase proteins.

Acute-Phase Proteins↗
PubMed1996

Blood protein interactions with titanium surfaces.

Protein adsorption and complement activation were studied on thin evaporated films of titanium (Ti). The surfaces were cleaned in either a radio frequency (RF) plasma unit, or washed sequentially in trichloroethylene, acetone, ethanol, and water. Both methods resulted in hydrophilic surface with low carbon contamination on the outermost oxide (approximately 11-13 at%). In situ ellipsometry suggested that Ti is an intrinsic coagulation activator in vitro, since significant amounts of factor XII (F XII) and high molecular weight kininogen (HMWK) were found on the surfaces after 1 min incubation in heparin plasma. Ellipsometry, performed after serum incubations ranging from 15 s to 30 min showed that the total amount of serum proteins and the deposition of antibodies to complement factor 3c (C3c) increased with serum incubation time. ELISA methods showed increased levels of free iC3b in serum after 10 min incubation of the surfaces, but no detectable amounts of C3 convertase fractions C4d or Bb. Ellipsometric results indicated, however, an increased deposition of antibodies to CIq and IgG on Ti after short serum incubation times. The combined results indicate that Ti-surfaces initially activate complement through the classical pathway. The activation then continues via a positive amplification loop where increased amounts of C3 are deposited on the surfaces via the alternative pathway.

Acetone↗
PubMedDate not supplied

Inverse social gradient of secondary immune response parameters in children.

BACKGROUND: In children, the prevalence of allergy increases with increasing socioeconomic status. If frequent immune response stimulation by infections protects against development of allergic diseases, then a social gradient in infections should exist. The aim of our study was to assess the relation between social class, immune parameters, and the prevalence of respiratory infections in children. METHODS: A cross-sectional survey examined children aged 5 to 14 years in 3 communities of Sachsen-Anhalt, Germany. Data of 1724 children were gathered by a parent-completed questionnaire and analyses of blood samples. Social class was defined by parental educational level. Immune parameters included serum immunoglobulin (Ig)G, IgA, and IgM; the C3c component of complement; and the total leukocyte count. The period prevalence of febrile colds and lifetime prevalences of physician-diagnosed bronchitis, tonsillitis, otitis media, and pneumonia were assessed from parents' reports. Adjusted odds ratios for the association between social class and belonging to the group of children with immune parameter levels in the upper 50th or 75th percentile or experiencing respiratory infections were calculated by logistic regression. RESULTS: Social class was inversely associated with secondary immune response parameters (IgG, IgA), whereas indicators of primary immune reactions and inflammation (IgM, C3c, leukocytes) were not related to social status. While an inverse social gradient was found for the period prevalence of febrile colds, the frequency of bronchitis, tonsillitis, and otitis media decreased with decreasing social class. CONCLUSIONS: Health inequalities exist in immune reactions and respiratory infections in children from different social classes. We hypothesize that in children from lower social classes, increased frequency of infections stimulated the secondary immune response and protected against more severe courses of respiratory infections.

Adolescent↗
PubMed1979

The immunologic and clinical associations of the split products of C3 in plasma in juvenile rheumatoid arthritis.

A qualitative counterimmunoelectrophoretic assay for the complement activation products C3c and C3d was used to study plasma from children with juvenile rheumatoid arthritis (JRA) and other rheumatic diseases. Positive tests for C3c,d were found in all patients with active systemic lupus erythematosus (SLE), 7 of 10 patients with active systemic JRA, 16 of 29 with active polyarticular JRA, 7 of 20 with active pauciarticular JRA, and in only 2 of 20 with inactive joint disease. The incidence of positive assays for C3c,d in JRA was increased in the presence of positive latex fixation tests, antinuclear antibody tests, or elevated values for antiglobulins as determined by affinity chromatography, but these associations were not statistically significant. Three joint fluids from children with pauciarticular JRA were negative for C3c,d. These studies show that the subgroups of JRA defined by clinical criteria are heterogeneous by current laboratory parameters and that evidence implicating antigen-antibody complexes in the pathogenesis of JRA is lacking in many patients.

Antibodies, Antinuclear↗
PubMed1978

Complement components in blood serum and suction blister fluid in erythropoietic protoporphyria.

Complement factor's C3c, C4, factor B, C3d and the immunoglobulin IgA were determined in suction blister fluid of patients with erythropoietic protoporphyria and in normal controls. The levels increased when the skin of the patients had been previously irradiated with 'white light', but with Kromayer radiation, and were interpreted as being the result of increased vasopermeability.

Adult↗
PubMed1984

[Serum immunoglobulins and complement fractions in protein malnutrition].

Serum immunoglobulins and some complement components (C1q, C3c, C4, factor B, C9) have been evaluated in 99 malnourished patients. The sole abnormality which seems related to protein calorie malnutrition is a C1q decrease significantly correlated to serum albumin, thyroxin binding prealbumin and retinol binding protein. The immunoglobulins modifications seem to be related to pathological conditions associated with malnutrition (sepsis, liver diseases).

Adult↗
PubMed1982

Proteolytic activity of selected clinical isolates of Serratia marcescens against human serum proteins.

Six representative clinical isolates of Serratia marcescens were examined for proteolytic activity against various proteins of normal fresh human serum. The extent of proteolytic activity was screened with micro-scale immunoelectrophoresis and quantitatively documented with the aid of Laurell's rocket electroimmuno assay. The 6 S. marcescens strains regularly altered, albeit to varying degrees, complement components C3a, C3c, C4, C5, and C9, and haptoglobin. Apolipoprotein and immunoglobulin A, the latter derived from human colostrum, were attacked by 5 and 4 isolates, respectively. Two isolates altered alpha 1-antitrypsin, whereas only one isolate interacted with alpha 2-macroglobulin and transferrin. In contrast, alpha 2-HS-glycoprotein, alpha 1-antichymotrypsin, and serum IgA, IgG, and IgM immunoglobulins were not affected by the test strains.

Alpha-Globulins↗
PubMed1984

HLA antigens and the complement system in essential hypertension.

Heredity factors are of great importance in the pathogenesis of essential hypertension, but their role was until recently not reliably proved. It was only after research into histocompatibility antigens that it was possible to discover the genetic determination of a number of diseases. The purpose of the study was to reveal the genetic factors raising the risk of essential hypertension (EH). In the population of Russian nationality in Moscow, suffering from EH, HLA antigens and certain complement components were investigated. The results showed an increased frequency of HLA-A11, HLA-B13 and HLA-Bw22. However, blood C3c and C4 concentration was in the studied group of patients significantly elevated, which attests to a possible participation of the complement system in the development of EH as a factor causing vasoconstriction. The results confirm the need for further study of the immunogenetic profile of patients with EH in order to clarify certain aspects of the pathogenesis of EH.

Adult↗
PubMed1994

Effect of gamma-interferon on the synthesis of the functional alternative and terminal complement pathways by human umbilical vein endothelial cells in vitro.

The cytokine gamma-interferon (gIFN) has been reported to modulate synthesis by endothelial cells (EC) of alternative pathway complement factors (H, I, and B). However, the net effect of gIFN on the synthesis and expression of the functional alternative and terminal pathways has not yet been reported. EC cultured under serum-free conditions were treated with different concentrations of gIFN and simultaneously co-incubated with agarose beads, which activate the alternative pathway. C3b and the terminal complement complex (TCC) bound to co-incubated beads were measured by radioimmunoassay using anti-human C3c and TCC antibodies. gIFN in concentrations 500-4000 U/ml increasingly reduced the amount of C3b and TCC detected on the beads. The down-regulating effect of gIFN on EC complement biosynthesis may be physiologically relevant by locally controlling complement activation.

Antibody Specificity↗