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PubMed1992

Complement activation by polyclonal immunoglobulin G1 and G2 antibodies against Staphylococcus aureus, Haemophilus influenzae type b, and tetanus toxoid.

To obtain information on effector functions of human immunoglobulin G2 (IgG2), we have measured the complement-activating properties of polyclonal IgG subclass antibodies against bacterial antigens. IgG1 and IgG2 were purified from serum samples from five healthy individuals, and complement activation was measured with different bacterial antigens. We used Staphylococcus aureus Wood 46 (STAW), which is a common antigen, Haemophilus influenzae type b (Hib), which is a common pathogenic microorganism in children, and formaldehyde-inactivated tetanus toxin (TT). Bacteria were incubated with antibodies and then incubated with sera from agammaglobulinemic patients as a complement source, and C3c deposition was measured by enzyme-linked immunosorbent assay. We found that anti-STAW IgG2 activated complement to a level similar to that of anti-STAW IgG1. Anti-Hib IgG1 complement activation was as much as seven times higher than that of anti-Hib IgG2 in four individuals. In one individual, anti-Hib IgG2 was more effective in complement activation than anti-Hib IgG1. Anti-TT antibodies showed patterns similar to those of anti-Hib. Our results indicate that IgG2 antibodies may contribute significantly to antibacterial defense. Also, individual differences in antibody effector functions should be taken into account when evaluating the immune status of patients and during early phase 1 studies of new vaccines.

Antibodies, Bacterial↗
PubMed1990

[Platelet immunoglobulins and complement in idiopathic thrombocytopenic purpura. Specificity to the IIb/IIIa membrane complex].

Platelet-associated IgG, IgM and C3c was studied by an enzyme-linked immunosorbent assay (ELISA) procedure using polystyrene microter plates and solubilize platelets. At the time of investigation patients fell into the following disease categories: 24 chronic ITP, 10 acute ITP and 11 ITP in remission (normal platelet counts). A significant elevation of platelet IgG was found in acute and chronic ITP. The C3c was increased in acute categories and normal in the others. There was not significant difference in the immunoglobulins and complement values between ITP in remission and normal donors. The platelet specificity of IgG and IgM antibodies to IIb/IIIa membrane complex was positive in 20% from chronic ITP and in none from acute. It is concluded that an elevated platelet immunoglobulins or complement is usefull for ITP diagnosis but the difference between acute and chronic categories only is possible in some cases by the antibodies specificity.

Blood Platelets↗
PubMed1995

A murine model for the study of mycotic mastitis.

This study established a murine model for the study of mycotic mastitis. The mammary glands of BALB/c mice were inoculated on the fifth day of lactation with graded doses (10(4), 10(5) and 10(6) cells) of a pathogenic strain of Candida krusei isolated from bovine mastitis. The animals were killed 1, 2, 3, 4 or 5 days after inoculation. In the infected mammary glands, the pathological reaction consisted of primary infiltration with heterophils and mononuclear cells, focal necrosis, formation of microabscesses, epithelial hyperplasia and some fibrosis. The severity of the changes was dose-dependent and increased with time after infection. An increase in the plasma concentrations of complement factors C1, C3c, C4 and C5, factor B and alpha-2-macroglobulin suggested that an acute phase response and activation of the complement system had occurred as a result of the infection.

Acute-Phase Reaction↗
PubMed1994

[Effect of hemodialysis using cuprophan and polysulfone dialyzers on rosette tests, concentration of immunoglobulins and complement components in serum of patients with chronic renal failure].

In 15 patients with chronic renal failure, the effect was studied of haemodialysis using cuprophan and polysulfone dialyzers on rosette tests, and the concentrations of immunoglobulins and C3c and C4 complement components in peripheral blood. It was found that the per cent of E and EAC rosettes decreases within 30 minutes of the procedure, IgG, IgA and IgM levels increase after 120 minutes of the procedure, while the concentrations of C3c and C4 components are not changing significantly during haemodialysis using both types of the dialyzers. The authors found that the polysulfone membrane seemed not to be more biocompatible than the cuprophan one.

Adult↗
PubMed1983

Classical pathway activation during an adverse response to protamine sulphate.

A severe anaphylactoid reaction was observed following the i.v. administration of protamine sulphate in a 66-year-old male undergoing coronary artery catheterization. Serial measurements of complement factors (C3 and C4) and C3 split products (C3c and C3d) were performed by conventional electro-immunoassays and by double zone rocket immunoelectrophoresis. A parallel decrease in circulating C3 and C4 concentrations was seen for 1 h, reaching a nadir at 1.3 h. Markedly increased concentrations of C3c and C3d were observed in the first sample examined after exposure to the drug. C3c and C3d concentrations gradually declined to the normal range within 5.9 h and 21.8 h, respectively. These observations are discussed in relation to the mechanism of this adverse reaction.

Aged↗
PubMed1991

Inhibition of chemotaxis of neutrophil leukocytes to interleukin-8 by endotoxins of various bacteria.

The effects of endotoxins from various bacteria (Escherichia coli, Klebsiella pneumoniae, Vibrio cholerae, Shigella flexneri, Salmonella typhosa, and Pseudomonas aeruginosa) on chemotaxis of neutrophil leukocytes to formyl peptide and interleukin-8 were tested in an improved chemotaxis assay involving a "sparse-pore" polycarbonate (Nuclepore) membrane in a Boyden-type chamber. The possible chemotactic activity of the endotoxins themselves were tested by the same technique. In addition, the effects of these substances on random motility of neutrophils were tested with a corresponding assay involving similar chambers fitted with membranes of standard pore density. Possible activation of the complement system of serum by each endotoxin was tested with sheep erythrocyte assays and the maximum endotoxin concentration (100 micrograms/ml) used in the chemotaxis and motility assays. All endotoxins inhibited chemotaxis of neutrophils to interleukin-8. No endotoxin affected chemotaxis to formyl peptide or was itself chemotactic for neutrophils. Endotoxin of S. flexneri inhibited random motility of neutrophils, while the others had no such effect. Endotoxins of K. pneumoniae and of P. aeruginosa produced moderate and marked inhibition, respectively, of total complement, as measured by hemolysis of sheep erythrocytes, without affecting the levels of C3c and C4 in these assays. Endotoxins of the other bacteria had no demonstrable effect in any of these assays of complement activation. These results suggest that chemotaxis to interleukin-8 may be mediated by cellular mechanisms different from those involved in chemotaxis to formyl peptide. Furthermore, the presence of these endotoxins could be significant for the suppression of neutrophil accumulation in inflammatory lesions mediated by interleukin-8.

Bacterial Toxins↗
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↗