Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Complement C3c”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources

Acute phase and opsonin response in cardiac surgery patients: influence of underlying cardiac disease.

Cardiopulmonary bypass (CPB) leads to an activation of plasma cascade systems, complement activation, and an acute phase response. To evaluate the influence of the underlying cardiac disease on the activation pattern of these systems, we compared inflammatory changes in coronary artery bypass grafting (CABG) patients with patients undergoing aortic valve replacement. We investigated changes of the acute phase proteins alpha 1-proteinase inhibitor and fibrinogen, the unspecific opsonin fibronectin, and the complement components C3c and C4 induced by extracorporeal circulation in 12 patients undergoing aortic valve replacement and in 12 patients undergoing CABG. Concentrations of C3c and C4 decreased in both groups after the onset of CPB and C4 concentration remained below post-induction levels up to 24 h after onset of CPB (p = 0.04). Fibronectin levels dropped immediately before the onset of CPB (p = 0.01), reaching the lowest values after 20 min of extracorporeal circulation. Fibrinogen and alpha 1-proteinase inhibitor levels after induction of anaesthesia were significantly higher in the CABG group and remained higher throughout the entire study period (p < 0.001). As an indicator of a postoperative acute phase response, concentrations of both proteins rose in the postoperative period above post-induction levels (p < 0.02).

Acute-Phase Reaction↗

Biochemical indices may not accurately reflect changes in nutritional status after allogeneic bone marrow transplantation.

The validity of biochemical indices routinely used for nutritional assessment was evaluated in patients undergoing allogeneic bone marrow transplantation for hematologic malignancies. Sixteen patients received total parenteral nutrition (TPN) for 15 days (35 kcal kg.body wt-1.day-1; 1.4 g amino acid.kg body wt-1.day-1) starting 1 day after transplantation. Nutritional status was evaluated before and after the TPN period by determining anthropometric (body weight, triceps skinfold thickness, and midarm circumference) and biochemical (transferrin, prealbumin, ceruloplasmin, and C3c) indices. Anthropometric indices, which were within the normal range before TPN, were not changed on day 15; transferrin and prealbumin concentrations significantly (p = 0.03) decreased whereas ceruloplasmin and C3c significantly (p = 0.03) increased. The levels of acute-phase proteins (alpha-1-acid glycoprotein, alpha-1-antitrypsin, and C-reactive protein), determined in 8 of the 16 patients at the same time intervals, were increased after 15 days of TPN and were significantly inversely correlated with transferrin and prealbumin. On the basis of these data, it appears that biochemical indices are not sufficiently reliable in the nutritional assessment of bone marrow transplantation patients because the levels of these substances are markedly affected by the acute-phase response secondary to febrile episodes and graft-versus-host disease, which frequently complicate transplantation.

Acute-Phase Proteins↗

Alzheimer's disease and senile brains: an immunofluorescence study.

The results obtained with direct immunofluorescence techniques on normal, senile and Alzheimer's disease brains are reported. The antisera used were directed against C3c, IgG (gamma chain), IgG Fc., kappa and lambda light chains and anti-Ig (total). The brain samples were prepared in different ways: formalin-fixed and paraffin embedded; fresh frozen samples and alcohol fixed, paraffin-embedded samples. The images obtained with the different processing methods did not coincide. In order to obtain a more complete picture, we suggest the use of different methods on the same samples. In Alzheimer's disease brains, abundant but probably not monoclonal Ig antigenic determinants were found. Ig were found diffusely in the tissue, connected to amyloid (both in senile plaques and blood vessel walls), in glial cells and neurons. The significance of such data in relation to the genesis of brain amyloid are discussed.

Adult↗

Detection of immune deposits in skin lesions of patients with Wegener's granulomatosis.

BACKGROUND: Wegener's granulomatosis (WG) is considered a pauci-immune systemic vasculitis based on the absence of immune deposits in renal biopsies of patients with active disease. In animal models of antineutrophil cytoplasmic antibody (ANCA) associated glomerulonephritis, immune deposits along the glomerular capillary wall are present at early stages of lesion development. These deposits are degraded rapidly, resulting in "pauci-immune" lesions. OBJECTIVE: To test the hypothesis that immune deposits can also be detected in early lesions of patients with WG, thereby initiating an inflammatory reaction that, in time, is augmented in the presence of ANCA, resulting in pauci-immune lesions later on. METHODS: The presence of immune deposits in skin biopsies taken within 48 hours of lesion development was investigated. Direct immunofluorescence was used to examine 32 skin biopsies for the presence of immune deposits (IgG, IgA, IgM, C3c). When possible, a comparison was made between the immunofluorescence findings in renal and skin biopsies taken at the same time. RESULTS: Four of 11 biopsies taken at initial presentation and four of 21 biopsies taken at the onset of a relapse of WG showed IgG and/or IgA containing immune deposits in the subepidermal blood vessels. All nine renal biopsies showed pauci-immune glomerulonephritis, irrespective of the presence (n=5) or absence (n=4) of immune deposits in the skin biopsy. CONCLUSION: A substantial number of skin biopsies showed immune deposits during active disease. These results could support the hypothesis that immune complexes may trigger vasculitic lesions in WG.

Adult↗

[The influence of intraoperative autotransfusion (IAT) on plasmaproteins in patients with posttraumatic intraabdominal bleeding or hemorrhage during vascular surgery (author's transl)].

In 29 patients (12 vascular and 17 trauma cases) the effect of intraabdominal bleeding and surgical management under intraoperative autotransfusion on several plasmaproteins was examined. The following parameters were monitored immediately before and after autotransfusion as well as 24, 48, 72 hours and one week later, in the thawed serum: 1. albumen and the carrier proteins prealbumen, transferrin, retinol-binding protein, 2. acute phase reactants: c-reactive protein coeruloplasmin, haptoglobin, 3. fractions of complement: C1q, C3c, C5 and C 3-activator, 4. serum-cholinesterase. With usual treatment by infusion of electrolyte solutions during operation and the following days, and further applicated blood transfusion, plasma and fresh frozen plasma by clinical needs, while the immediate blood loss during operation was replaced by autotransfusion, there was no change in preoperative dates. Only at the 3rd day the typical picture of catabolic situation of the postoperative period was observed in vascular cases and not at all in trauma cases. Thus the changes were closely related to the preexisting disease or state of shock, without further detoriation by intraoperative autotransfusion. 7 days later a sometimes overshooting normalization of the parameters was observed. Only cholinesterase remained extremely low, especially in vascular cases.

Abdominal Injuries↗

Complement activates neutrophils during PTCA procedure in patients with unstable angina pectoris.

We estimated adherence, aggregation and chemiluminescence of neutrophils as well as concentrations of C3c, C4 and C5 complement components and complement haemolytic activity (CH50) in 27 patients with unstable angina pectoris subjected to percutaneous transluminal coronary angioplasty (PTCA). The control group consisted of 12 patients with unstable angina pectoris, in whom coronary angiography was performed but PTCA was decided against for various reasons. Blood samples for examination were taken from coronary sinus and peripheral vein just before, 1 min and 20 min after PTCA or coronary angiography. We observed enhancement of neutrophil adherence, aggregation and chemiluminescence, and decrease in concentrations of C3c, C5 and complement haemolytic activity (CH50) after PTCA procedure. In conclusion we think that ischemia resulting from PTCA causes complement activation in an alternative pathway which seems to be connected with neutrophil activation.

Acute-Phase Reaction↗

HIV is trapped and masked in the cytoplasm of lymph node follicular dendritic cells.

To gain further insight into the pathogenesis of human immunodeficiency virus (HIV) infection, lymph nodes from seven asymptomatic HIV+ subjects were analyzed during the latent phase of disease. Both ultrastructural and immunohistochemical analyses revealed that, in all of the cases, plasma cells producing IgM/gamma were present in germinal centers. Secreted immunoglobulins formed extracellular deposits mimicking the follicular dendritic cell network. Immunoglobulin produced by germinal center plasma cells are specific for HIV because they bind the HIV env protein gp 120. Plasma cells producing antibodies with the same specificity were also abundant in the extrafollicular regions of lymph nodes. During the latent phase of infection, the virus largely accumulates within the germinal centers. Therefore, extracellular immunoglobulin may form immune complexes, as shown by the presence of HIV-specific antibodies, HIV particles, and complement components C3c, C3d, and C1q in the interdendritic spaces. When the ultrastructural localization of HIV in germinal centers was analyzed, abundant virus particles were found in the interdendritic spaces. In addition to this extracellular localization of HIV, receptor-mediated endocytosis of viral particles by follicular dendritic cells was observed. Complete HIV particles were found within the endosomal compartment of the follicular dendritic cells and, as complete viral particles, free in the cytoplasm, indicating that the virus may escape from the endocytic compartment. As the virus is abundant in the cytoplasm, this event leads to formation of a hidden reservoir within follicular dendritic cells. In this location, HIV escapes recognition by cytotoxic T lymphocytes. In contrast, virus budding indicating a productive infection of follicular dendritic cells that would render them susceptible to T-cell-mediated lysis has been seldom observed.

Antigen-Antibody Complex↗

[Antibodies to tetanus toxoid in children from areas with different heavy levels of air pollution].

The aim of this study was to investigate the relationship between different levels of air pollution and IgG antibody titers against tetanus toxoid in sera of 6 year old children (n = 354). Additionally, other parameters of the humoral immune response (immunoglobulins G, A, M, total IgE, complement component C3c, C-reactive protein (CRP)) were analysed. The index areas were Leipzig, Magdeburg (Saxony/Saxe-Anhalt), and Duisburg, Dortmund (Ruhr region). The control areas were Osterburg and Borken. IgG antibodies against tetanus toxoid were measured by ELISA in sera of children vaccinated three times DPT in early childhood. The other humoral parameters were measured by nephelometry. In comparison to the control area Borken the sera of children living in the index areas Duisburg and Dortmund showed a lower antibody titer. There were no differences between the index areas (Leipzig, Magdeburg) and the control area Osterburg. It has to be taken into account that the choice of Osterburg as a control area is problematic because of the lack of data on air pollution. Statistically, there was no relationship between antibody titer against tetanus toxoid and the additionally measured parameters of the humoral immune response.

Air Pollutants↗

Activity and activation of the complement system in patients being operated on for cancer of the colon.

OBJECTIVE: To find out if there was any local activation of complement in the vicinity of a colonic cancer, and any fluctuation in the function of the complement system during operation. DESIGN: Prospective study. SETTING: One university and two district hospitals in Denmark. SUBJECTS: 29 selected patients undergoing emergency and elective operations for colonic cancer. INTERVENTIONS: Measurements of systemic and local complement fixation capacity and complement activation in samples of serum or plasma taken before, during, and after operation. MAIN OUTCOME MEASURES: Changes in complement fixation capacity and complement activation during operation. RESULTS: Haemodilution during operation caused a significant reduction in the complement fixation capacity of serum and in the activation of the complement system as measured by generation of C3c. We were unable to confirm the presence of complement inhibitors during operation. Haemodilution caused a 30% reduction in fixation capacity of C3b (12/29 samples of serum had values more than 2SD below the mean of the reference range compared with 4/29 before operation). The activity of C4 was reduced by 25% during operation and the capacity of the complement system to fix C3b and C4b was restored to baseline nine days postoperatively. Concentration of C3d was significantly higher in serum from tumour venous blood compared with that from peripheral blood during operation. CONCLUSION: The presence of complement activation products in the general circulation reflects local activation of the complement system in the vicinity of the tumour, but this may have been influenced by tissue necrosis or subclinical infection. Haemodilution causes a significant reduction in the capacity of the complement system during operation, whereas inhibitory factors associated with the cancer or operation and anaesthesia could not be demonstrated. We found no correlation between complement activity and clinical data.

Adult↗

Studies on coagulation, fibrinolysis, kallikrein-kinin and complement activation in systemic and pulmonary circulation during hip arthroplasty with acrylic cement.

This study was designed to evaluate the contribution of the plasma cascade systems to the cardiopulmonary complications, occasionally leading to sudden death during hip arthroplasty using acrylic cement. The intraoperative pattern following uneventful surgery was therefore investigated in 8 patients with osteoarthrosis with frequent sampling from the radial and pulmonary arteries. The following general findings emerged: A gradual consumption of coagulation factors (platelets, fibrinogen, factor VII, antithrombin III), fibrinolytic components (plasminogen, alpha-2-antiplasmin), kallikrein-kinin factors (prekallikrein, kallikrein inhibitor) and complement factors (C3c, C4) was observed. Some intrapulmonary proteolytic inhibition was noticed as evidenced by lower arterial than mixed venous blood levels of alpha-2-antiplasmin and kallikrein inhibitor. Insignificant changes occurred for factor VII-phospholipid complex. A rapid, massive and transient increase in fibrinopeptide A (FPA) values in the radial artery, as opposed to the moderate increase in the pulmonary artery, was found immediately after reaming and broaching of bone. This probably reflected intrapulmonary fibrinogen to fibrin conversion, reaching a maximum 15-20 minutes before the femoral implantation. As estimated from the FPA arterial peak values and the fall in fibrinogen concentrations, approximately 5-10% of the circulating fibrinogen molecules were devoided of FPA during this intraoperative phase. The marked a-v difference in FPA level supports earlier findings of intrapulmonary fibrin formation and deposition. This process, however preceded the critical period of cardiorespiratory collapse (CRC) by at least 15 minutes, and may thus predispose to this complication.

Acrylates↗

Circulating immune complexes in Meniere's disease.

Sixty-six patients with Meniere's disease were studied for possible general immunologic abnormalities. The disease was bilateral in 20 cases, causing active symptoms in 49. Thirty-six healthy control subjects were also studied. Immune activity was assessed by quantitative measurement of the circulating immune complexes, serum immunoglobulin assay, and acetate electrophoresis, and by an autoantibody screen to a battery of ten general tissue antigens. Thirty-six (54.5%) of the 66 patients with Meniere's disease were found to have significantly raised circulating immune complex levels compared with one (2.9%) of the 36 controls. A statistically significant increased incidence of autoantibodies was also found in the Meniere's group.

Adolescent↗

Treatment of cancer chemotherapy-associated thrombotic thrombocytopenic purpura/hemolytic uremic syndrome by protein A immunoadsorption of plasma.

BACKGROUND: Chemotherapy-associated thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (C-TTP/HUS) is a condition involving thrombocytopenia, microangiopathic hemolytic anemia, and progressive renal dysfunction that develops in 2-10% of patients with a history of malignant neoplasms treated with certain chemotherapeutic agents. Pathogenesis of the disease may depend on the following: (1) generation of endothelial lesions in the kidney microvasculature, resulting from drug toxic effects and/or generation of small soluble circulating immune complexes (CIC), and (2) generation of autoantibodies and/or CIC that trigger aggregation and deposition of platelets around the lesions. METHODS: Extracorporeal immunoadsorption treatment of plasma (PROSORBA columns, IMRE Corporation, Seattle, WA) to remove immunoglobulin G and CIC was evaluated in 55 patients for the potential to induce significant clinical benefits (increase in platelet count, decrease in hemolysis, stabilization of renal function) and longer survival. RESULTS: Response to therapy was achieved in 25 of 55 patients examined. Response was associated with an estimated 1-year survival rate of 61%, as compared with an estimated survival rate of only 22% in those who did not respond (P = 0.0001). Patients whose malignant neoplasms were in complete or partial remission at the time of development of C-TTP/HUS had a significantly higher estimated 1-year survival rate (74%) as compared with a historic control group of patients receiving other treatments (22%, P = 0.0161). Clinical responses were correlated with normalization of serum levels of CIC and complement components C3c and C4. There were no side effects associated with 75% of treatments. Immunoadsorption therapy was associated with generally mild to moderate manageable side effects, such as fever, chills, nausea/vomiting, respiratory symptoms, pain, hypertension, and hypotension, which were reported in 25% of procedures. CONCLUSIONS: This multicenter study establishes protein A immunoadsorption as an effective and safe treatment for cancer chemotherapy-associated TTP/HUS, an otherwise fatal disease.

Adult↗

TEM immunogold staining of C3 from plasma onto titanium oxides.

Immunogold staining in conjunction with TEM was used to observe C3 adsorption from plasma in relation to the underlying titanium structure of thermal, anodic, and electropolished oxides. Heat treatments and oxide thickness were found to have no significant effect on the adsorption behavior of C3, while surface oxide type possibly has. Surface concentration of C3 was found to be time- and plasma concentration-dependent. Evidence is given for the possible involvement of C3 in protein exchange, i.e., the Vroman effect. Diluted plasma resulted in a random distribution of gold colloids, whereas clustering occurred with undiluted plasma. Although C3 concentrations present on grain boundaries followed the same trend as that found on the surface, C3 was found to have a higher grain boundary than bulk concentration for 0.1% plasma.

Adsorption↗

In vitro plasma protein adsorption and kallikrein formation on 3-mercaptopropionic acid, L-cysteine and glutathione immobilized onto gold.

3-Mercaptopropionic acid (MPA), L-cysteine (L-cys), and glutathione (GSH) monolayers were immobilized onto gold and used in in vitro protein tests. The surfaces were characterized with ellipsometry, static contact angle measurements, atomic force microscopy, and Fourier transform infrared reflection absorption spectroscopy (FT-IRAS). After incubations in human plasma and antibody solutions, the surface antisera binding patterns were determined with ellipsometry. Using serum instead of plasma, complement activation was studied in the same fashion. Activated coagulation Factor XII and kallikrein formation on the surfaces and in the plasma were studied using a kallikrein-specific colorimetric assay. 3-Mercaptopropionic acid indicated contact activation of coagulation but L-cysteine did not. Glutathione displayed low deposition of plasma proteins, large deposition of proteins from serum, and did not promote kallikrein formation. None of the surfaces could be attributed complement activating properties, as determined by antibody deposition. The present study demonstrates that surface biology in complex model systems can be conveniently studied in vitro through systematic and well defined surface modifications.

3-Mercaptopropionic Acid↗

Systemic autoimmunity due to mercury vapor exposure in genetically susceptible mice: dose-response studies.

Six groups of genetically mercury-susceptible female SJL/N (H-2s) mice were exposed to mercury vapor at a concentration of 0.3-1.0 mg Hg/m3 air for 0.5-19 hr/day 5 days a week for 10 weeks. The absorbed doses were calculated to be between 75 and 2365 micrograms Hg/week/kg body wt (micrograms Hg/week/kg). The correlation between the dose and the concentration of Hg in kidney, spleen, and thymus was highly significant (p < 0.0001; Spearman's rank correlation test). The lowest observed adverse effect level (LOAEL) for serum IgG antinucleolar antibodies (ANoA) was 170 micrograms Hg/week/kg, corresponding to a renal mercury concentration of 4.0 +/- 0.76 micrograms Hg/g wet wt. The correlation between the absorbed dose and the ANoA titer was highly significant (p < 0.0001; Spearman's rank correlation test), and all mice were ANoA-positive at a dose of 480 micrograms Hg/week/kg. High-titer ANoA targeted the nucleolar 34-kDa protein fibrillarin. The LOAEL for B-cell stimulation, measured as an increase in serum IgG2a and IgG1 concentrations, was 360 micrograms Hg/week/kg, but the increase was fivefold higher and also included IgE at a dose of 690 and 2365 micrograms Hg/week/kg. The serum Ig concentrations peaked after 2-4 weeks and then slowly declined but, except for IgE, remained significantly increased during the entire exposure time. Glomerular, mesangial IgG immune complex (IC) deposits, accompanied by systemic vessel wall IC deposits, were first detected at a dose of 480 micrograms Hg/week/kg. The mesangium also showed increased titers of IgM IC deposits and complement factor C3c. The correlation between the absorbed dose, and the individual titer of IgG, IgM, and C3c, was highly significant (p < 0.0001; Spearman's rank correlation test). In conclusion, mercury vapor efficiently induced an autoimmune syndrome in genetically susceptible mice, and the LOAEL for the adverse effects varied in the order ANoA < B-cell stimulation < IC deposits. Comparing the body burden of mercury in mice at the LOAEL for autoantibodies with the body burden in populations of occupationally exposed humans suggests that the safety margin may be narrow for genetically susceptible individuals.

Administration, Inhalation↗

Fungal cell adhesion molecules in Candida albicans.

Adherence of Candida albicans to host tissues is considered a crucial step in the pathogenesis of candidiasis. Using in vitro assays, it was demonstrated that the yeast-mycelium transition was an important phenomenon in the acquisition of adhesive properties. Proteins with MWs of 60, 68, 200 and greater than 200 kDa seemed to be involved in germ tube adherence to plastic surfaces. Likewise, recent investigations have revealed that C. albicans expresses on its surface receptors which interact with a wide variety of host proteins, particularly some extracellular matrix components like fibronectin, laminin and collagen. Plasmatic components, such as fibrinogen, iC3b and C3d, have also been proposed as mediators of adherence of C. albicans. Thus, by their reaction with laminin, fibrinogen and C3d, the mannoproteins of 68 and 60 kDa demonstrated multiple biological activities. Proteins of similar MWs were detected as C3d and iC3b receptors, the latter showing similarities with the neutrophil CR3. Based upon the antigenic, structural and functional homologies between the candidal receptors and mammalian integrins, it was postulated that these fungal cell adhesion molecules (F-CAM) are members of the integrin family. Interactions with host proteins and molecular mimicry of mammalian adhesion molecules may be a fertile area for further research.

Basement Membrane↗

Complement C3, coeruloplasmin and PMN-elastase in the ejaculate in chronic prostato-adnexitis and their diagnostic value.

The clinical differential of chronic prostatitis and psycho-vegetative urogenital syndrome with objective laboratory tests is very difficult. 265 ejaculates with possible chronic prostatitis were bacteriologically examined (including the search for STD agents). To verify an inflammatory process in the prostate and adnexae, we tested the C3 complement, coeruloplasmin and PMN-elastase levels in ejaculate. In addition, semiquantitative leucocyte counts in stained smears of the ejaculate were carried out. 185 of 265 patients had C3 complement below detection levels or in the normal range excluding inflammation of prostate or adnexae. 16.8% of the C3-negative ejaculates showed an elevated PMN-elastase level associated with urethritis anterior and/or posterior caused by STD agents. 80 patients showed elevated C3 levels; 38.8% with elevated coeruloplasmin and PMN-elastase levels. The semiquantitative leucocyte count in the stained smear proved the least sensitive method for verifying an inflammation. Enterococci (55.3%), Mycoplasma (18.8%) and Escherichia coli (16.5) were the dominant pathogens of chronic prostatitis present in number of 10(2) cfu/ml or greater than 10(5) cfu/ml. A correlation to the intensity of the inflammation was not found. These results show how important it is to realise a complete bacteriological examination as well as to determine the C3 complement, coeruloplasmin and PMN elastase.

Adult↗

Activity of circulating monocytes in patients with chronic glomerulonephritis.

Monocytes of 95 patients with chronic glomerulonephritis (ch.g.) tested in vitro demonstrated characteristics of activation in proliferative, and of functional suppression in mesangiocapillary glomerulopathy. Fc and C3 receptor function studied by rosette assay and metabolic potential measured by the NBT reduction test constituted result patterns. Receptor tests were supplemented with their counterparts after monocyte triggering with heat-inactivated sera and in case of NBT assay - stimulation with zymosan. Membranous, minimal change, mesangial and focal glomerulonephritis monocytes presented less specific configurations of data than those of proliferative and mesangiocapillary, with a uniform increase of trypsin-resistant Fc receptor activity. There was no appreciable correlation between the presence of circulating immune complexes (c.i.c.) in patient sera and parameters tested. The mesangiocapillary "suppression pattern" suggests mononuclear phagocyte defect in this glomerulopathy.

Adolescent↗