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Host serum protein levels in cysts of human hydatidosis.

8 proteins (albumin, IgG, IgM, IgA, C3c, C4, orosomucoid and alpha 1 antitrypsin) were determined by laser immunonephelometry in hydatid cyst fluid from cysts and sera from 16 patients. The cystic level of albumin was 34.5 +/- SD 59.1 micrograms/ml (range 3.6-85); of IgG 12.9 +/- 18.7 micrograms/ml (1.9-75); of IgM 10.5 +/- 10.4 micrograms/ml (3-37); and of IgA 7.2 +/- 3.5 micrograms/ml (4-19.7). The 4 other proteins represented a smaller fraction: C3c, 0.9 +/- 0.6 micrograms/ml (0.5-2.5); C4, 1.3 +/- 0.9 micrograms/ml (0.5-3.5); orosomucoid, 2.8 +/- 2.3 micrograms/ml (1.4-9.2); and alpha 1-antitrypsin, 5 +/- 4.5 micrograms/ml (2-19). These 8 host proteins constituted 24.6 +/- 24.5% (2.4-76) of the total hydatid cyst fluid proteins (343.7 +/- 172.1 micrograms/ml, range 180-900). The albumin/IgG ration of 3 +/- 2.8 (0.4-10.8) in hydatid cyst fluid was more variable than that in sera, 2 +/- 0.5 (1.2-2.7).

Blood Proteins↗

Clinical significance of the alterations of plasma prostaglandin E2 (PGE2) in severely burned patients.

Agar gel single diffusion and radio immunological analyses were employed to determine the levels of serum C3c, C4, IgA, IgM, IgG and plasma PGE2 in 24 severely burned patients. The results were compared with the development of postburn immunosuppression, severe infection and MOF. There were marked decreases in serum C3c, C4 and Ig, which were especially marked in patients with MOF. Furthermore, plasma PGE2 decreased markedly in patients with MOF and/or severe systemic infection. The results suggest that the decrease of deficiency in plasma PGE2 was closely related to the immunosuppression and the development of severe systemic infection and/or MOF, which supported the hypothesis that PGE2 might play a role in immunoprotection, but not immunosuppression, in burned patients.

Adolescent↗

Immunological alterations in sera of persons living in areas with different air pollution.

The present study aimed to investigate immune parameters in sera of adult persons chronically exposed to different degrees of ambient air pollution. As related to air pollution derived from coal mining industry and coke plants, a significantly increased prevalence of cases with abnormally high serum levels of the immunoglobulins IgA and IgM as well as the complement component C3c was found as compared with a less polluted control area, indicating a higher stimulation of acute reactants in combination with a polyclonal immune response. These findings may be attributed to elevated concentrations of airborne particulates, suggesting that permanent exposure to increased levels of airborne particulates leads to chronic irritation of the airways in association with activation of the immune system, which may give rise to an enhanced risk for chronic airway diseases.

Air Pollutants↗

Rapid turbidimetric determination of serum C3c and C4 by end point centrifugal analysis.

An end point turbidimetric method for the determination of C3c and C4 in serum using a centrifugal analyzer (Cobas Bio) is described. Several analytical factors were evaluated -pH, temperature, PEG and antibody concentration. Wide variations of temperature and pH did not significantly affect the turbidimetric reaction. A 20 g/L PEG concentration and 25-fold antiserum dilution were found satisfactory for the analysis. Precision of the assay was good and comparison with a RID method yielded an r value of 0.97. The procedure is simple and reliable.

Centrifugation↗

Activation of rabbit C3: studies of the generation of cleavage products in vitro and of their metabolism in vivo.

The cleavage of purified, functionally active rabbit C3 by cobra venom factor and trypsin was analysed by reducing and non-reducing sodium dodecyl sulphate electrophoresis and autoradiography. The specific aim of the study was to compare these reactions to those that occur with human C3. Analysis showed that the pattern of breakdown was very similar to that for the human protein: while the beta-chain remained intact, there was step-wise degradation of the alpha-chain to form C3a, C3b, iC3b and C3c, all of which could be identified by gel analysis. The metabolic behaviour of three of these cleavage products, C3a, C3b and iC3b, was then examined in vivo using dual isotope techniques. Rabbits were studied simultaneously with 131I-C3 and 125I-labelled C3 breakdown products. Analysis of plasma and urine radioactivity for the subsequent 72 h showed that all three breakdown proteins had rapid rates of catabolism in vivo compared to the native molecule. Specifically, 93 and 98% of C3b and iC3b, respectively, were eliminated from the plasma compartment within 10 h of injection. C3a was completely eliminated within 10 h. By comparison, native C3 showed a half-life of 29 +/- 3 h (mean +/- SD) and a fractional catabolic rate of 4.30 +/- 0.75%/h. The data support the use of this species in studies of complement behaviour in models of human immune disease and further clarify the basis for changes in plasma C3 concentration that accompany active immune complex- and antibody-mediated activity, in vivo.

Animals↗

Immunopathological correlation between mesangial C3d-deposition and C3d-fixing circulating immune complexes in lupus nephritis.

By a direct immunofluorescent technique, glomerular C3d deposition was examined in a total of 50 renal biopsy specimens from patients with lupus nephritis. C3d deposition was then compared with disease activity, glomerular IgG and C3c deposition, and the levels of circulating immune complexes (CIC) measured by a solid-phase anti-C3d assay. There was a good correlation between disease activity and the positivity of glomerular C3d deposits (P less than 0.001), as well as C3c deposits (P less than 0.001). Even in clinically inactive patients, a relatively high percentage (59%) of C3d deposits were positive compared with C3c deposits (17%). Mesangial C3d deposition correlated with clinical disease activity more significantly (P less than 0.005) than capillary wall C3d deposition (P less than 0.025). C3d deposits were detected in all of the 30 cases with positive C3c deposits, and moreover, in 15 of the 20 (75%) cases with negative C3c deposits. Glomerular IgG deposits were almost always associated with C3d deposits, both in mesangial areas and along capillary walls, with statistical significance (P less than 0.005, P less than 0.001, respectively). The serum levels of C3d-fixing immune complexes (IC) were significantly correlated with the positivity and intensity of mesangial C3d deposits. This study demonstrates glomerular deposition of C3d in patients with lupus nephritis and reveals a significant correlation between mesangial C3d deposition and disease activity.

Antigen-Antibody Complex↗

Partial characterization of physiologically generated C3 components expressing C3d but not C3c epitopes.

Techniques for the quantification of C3d are shown to estimate the sum of 4 different plasma protein components possessing C3d but not C3c epitopes. All 4 components were C3-derived polypeptides as shown by activating serum containing 125I-labelled C3, isolating the anti-C3d reactive material in 14% PEG supernatant, followed by analysis on SDS-PAGE and autoradiography. Identical results were obtained by radiolabelling 14% PEG plasma supernatants followed by analysis of the anti-C3d reactive material. The components are referred to as d1, d1', d2 and d3 based on their relative electrophoretic mobilities (alpha 1, alpha 1, alpha 2 and alpha 2 respectively) judged by crossed immunoelectrophoresis. Their apparent molecular weights by SDS-PAGE were 129K (d1), 110K (d1'), 46K (d3) and 45K (d2). The possibility that one or more of the C3d containing components represented a complex of a C3 fragment with another plasma protein was investigated. The role of these components in the scheme of the physiological breakdown of C3 and the importance of the individual C3d components as indicators of complement activation in clinical materials is discussed. It is proposed that the 45K d2 component represents a final physiological breakdown product of C3 in human serum.

Antigen-Antibody Reactions↗

A rapid and reproducible method for the analysis of immune complexes using affinity chromatography and Western blotting.

A new procedure which couples different analytical techniques in a format permitting the rapid analysis of immune complex components is described. Complexes obtained from sera by polyethylene glycol (PEG) precipitation were resuspended and then added, using a batch method, to antibody coupled to Sepharose beads. Antibody directed against either human C1q or human C3c were used in the present study. Bound immune complexes were washed and then eluted from the Sepharose by sodium dodecyl sulphate (SDS) treatment and simultaneously reduced with dithiothreitol. Individual components were separated by SDS gradient polyacrylamide gel electrophoresis and then transferred to nitrocellulose by Western blotting. Individual strips of nitrocellulose were investigated using specific antisera and a radiolabelled probe. Immune complexes (IC) isolated from the sera of 7 rheumatoid arthritis (RA) patients were analysed using this method and the results obtained for both affinity adsorbents compared.

Antigen-Antibody Complex↗

Radioimmunoassay evaluation of anti-C3d reactivity in broad spectrum commercial antiglobulin reagents.

The study was undertaken to assess the potential of a labeled C3d radioimmunoassay method as a standardization criterion for antiglobulin reagents containing anti-C3d reactivity. Over an 18-month interval, four different lots of broad-spectrum antiglobulin reagents were purchased from each of seven United States manufacturers. Anti-C3d antibody concentration and Ko in each lot were assayed initially and at four-month intervals over 16 to 21 months storage at 4 degrees C. The results permitted 1) comparison of anti-C3d antibody concentrations among different manufacturers, 2) comparison among different lots from the same manufacturer, and 3) assessment of stability of anti-C3d during storage. In addition, serial dilutions of reagents in each manufacturer's diluent were compared for their anti-C3d agglutinating properties by the spin-antiglobulin method against red blood cells (RBC) coated by C3d in vitro and against in vivo C3d-coated RBC from 16 patients. Most reagents were shown also to contain anti-C3c, anti-C4c and anti-C4d reactivities when tested against suitably coated RBC. Anti-C3d antibody concentrations ranged from approximately 1 to 3.5 microgram/ml for 27 of the 28 reagents and were stable over 16 to 21 months of storage. Anti-C3d agglutination titer scores showed a general correlation with anti-C3d antibody concentrations when tested against in vitro C3d-coated RBC; correlations were less good against C3d-coated cells from patients. The radioimmunoassay provided reproducible objective measurements and appeared to have merit as a standardization criterion.

Anemia, Hemolytic, Autoimmune↗

A study of C3b deposition on yeast surfaces by sera of known opsonic potential.

C3c fragments released by the actin of trypsin from C3b molecules bound to zymosan may be readily quantitated by conventional gel techniques to give a measurement of the efficiency of C3b opsonization. Using this approach, the rate of deposition of C3b molecules was found to be very rapid in sera known to opsonize yeast normally. In contrast, sera defective in yeast opsonization deposited C3b much more slowly. The C3b elution technique was found to correlate well with both a direct phagocytosis assay using baker's yeast (r = 0.87, P less than 0.001) and a recently described neutrophil iodide uptake assay (r = 0.88, P less than 0.001).

Adult↗

Immunological studies on pre-eclampsia in Nigerian women.

Circulating immune complexes, C3b inactivator, C3 activator, C3c, C4 and C-reactive protein were assayed in 49 patients with pre-eclampsia and 35 apparently healthy pregnant Nigerian women. Pre-eclamptic women had significantly higher mean levels of circulating immune complexes, C3c and C-reactive protein. C3 activator mean level was also higher in pre-eclampsia than in normal pregnancy, C3b inactivator concentrations were greatly depressed and the mean level was also significantly lower in the pre-eclamptic group (P less than 0.001). However, C4 mean levels were the same in both groups. From the results, it is postulated that in pre-eclamptic conditions the significantly depressed levels of C3b inactivator could predispose to the persistence of deposited immune complexes in the kidneys, resulting in tissue damage. The findings also generally indicate an immunologic pathogenesis for the renal lesions in pre-eclampsia in Nigerian women.

C-Reactive Protein↗

Higher alpha 1-antitrypsin, haptoglobin, ceruloplasmin and lower retinol binding protein plasma levels during depression: further evidence for the existence of an inflammatory response during that illness.

Recently, a few reports have shown that severe depression may be associated with higher levels of positive acute phase proteins (APPs), such as haptoglobin (Hp), alpha 1-acid glycoprotein (alpha 1S) and lower levels of negative APPs (visceral proteins), such as albumin (Alb) and transferrin (Tf). In order to reassess whether depression is related to alterations in the expression of plasma APP concentrations, we measured in 84 normal controls and depressed inpatients positive APPs such as Hp, alpha 1-antitrypsin (alpha 1AT), hemopexin (Hpx), ceruloplasmin (Cp), complement component C3C and one visceral protein, i.e., retinol binding protein (RBP). We found increased plasma concentrations of Hp, alpha 1AT, and Cp in major depressed subjects as compared with healthy controls, with minor depressives exhibiting an intermediate position. RBP was significantly lower in minor and major depressives than in normal controls. The disorders in these proteins were rather sensitive (62%) for major depression, with a specificity equalling 96%. Our findings are compatible with the hypothesis that major depression may be accompanied by inflammatory changes with higher levels of positive APPs (i.e., alpha 1AT, Hp, Cp, alpha 1S) and lower levels of visceral proteins (i.e., RBP, Tf, Alb).

Acute-Phase Reaction↗

[Comparison of protein concentrations in saliva and serum].

Saliva and serum protein profiles composed of 12 proteins: IgA, IgG, IgM, albumin, transferrin, alpha 1-glycoprotein acid, alpha 2-macroglobulin, alpha 1-proteinase inhibitor, haptoglobine, C3C, C4 and CRP were obtained by laser nephelometry of aliquots of samples of non-stimulated whole saliva and blood taken at the same time. The population of 138 controls of both sexes was divided into 4 age groups: 1 (20 to 29 years), 2 (30 to 39 years), 3 (40 to 49 years), 4 (50 to 60 years). Using the techniques developed for saliva assay, 10 proteins were measurable: IgA, IgG, IgM, albumin, transferrin, alpha 1-glycoprotein acid, alpha 2-macroglobulin, alpha 1-proteinase inhibitor, haptoglobulin and C3C. The C4 fraction and CRP were present at concentrations lower than the detection limit i.e. at 1.8 and 2.05 mg/l. In the serum 11 proteins were analysed, CRP occurring at less than 0.01 g/l. The statistical two-factor variance analysis test (sex and age) demonstrated the statistically significant influence of age in the saliva for alpha 1-PI and alpha 2-M in the serum for Tf, alpha 2-M and alpha 1-PI, and sex in the serum for IgG, IgM, alpha 1-PI, alpha 2-M and also the interaction of both factors in the serum for alpha 2-M.

Adult↗

[Immunoelectron microscopic observation of membranous nephropathy in children using protein A-gold complex method].

The ultrastructural localization of immunoglobulins (IgG, IgA, IgM), complement component (C3c), or fibrinogen-related antigen (FRA) was investigated on 5 biopsy samples from 5 children with idiopathic MN or lupus nephritis using protein A-gold (PAG) complex method. The immunoreactivity of IgG was essentially confined to the mesangial and subepithelial electron-dense deposit (EDD) in all of 5 children, and more intense staining of IgG was observed in 3 children with stage II of MN than those with stage I and stage III of MN. Double immunocytochemical staining showed the same distribution of both IgG and IgM or both IgG and FRA in subepithelial EDD in 2 of 5 children. These findings suggest that IgG deposits are associated with the formation of subepithelial EDD in MN, and raise the possibility that IgM and FRA deposits may result from entrapment and/or immunological reaction.

Adolescent↗

The effects of gonadotropin treatment on the immunological features of male patients with idiopathic hypogonadotropic hypogonadism.

There is a significant line of evidence for a role of androgens in the modulation of the immune system. However, little is known about immunological features of male patients with idiopathic hypogonadotropic hypogonadism (IHH) and the potential effects of gonadotropin treatment. Thus, the objective of this study was to evaluate the levels of selected soluble immune parameters [IgA, IgG, IgM, C3c, C4, interleukin-2 (IL-2), and IL-4], the CD4+/CD8 ratio, and counts of total lymphocyte and some subpopulation of lymphocytes (CD3+, CD4+, CD8+, and CD19+ cells) before and after gonadotropin treatment in men with IHH. Twenty-nine IHH patients and 19 age-matched healthy controls were included in the study. The patients were treated with human menopausal gonadotropin/hCG for 6 months. The pretreatment levels of serum Igs, C3c, IL-2, and IL-4 in the patients were significantly higher than those in the controls (P<0.001 for all). After treatment, all Igs (P<0.001), C3c (P<0.01), and IL-2 and IL-4 levels (P<0.005) were decreased significantly compared to pretreatment levels. Pretreatment lymphocyte counts (P<0.05); the percentages of CD3+ cells (P<0.001), CD4+ cells (P< 0.001), and CD19+ cells (P<0.001); and the CD4/CD8+ ratio in the patient group were significantly higher (P<0.05) than those in the controls. After treatment, the lymphocyte count (P<0.001); CD3+ (P<0.01), CD4+ (P<0.001), and CD19+ (P<0.005) cells; and the CD4-/CD8+ ratio (P<0.001) were decreased, but CD8+ cells were increased significantly (P<0.001). In summary, lack of testosterone action results in the enhancement of cellular and humoral immunity. The results of this study allowed us to conclude that testosterone deficiency affects both cell-mediated and humoral immunity, and these may be modulated with gonadotropin therapy in male patients with IHH.

Adult↗

Vulvar lichen sclerosus: an immunologic study.

OBJECTIVE: To investigate the seroimmunologic (CD3, CD4, CD8 lymphocytes, C3c and C4 complement fractions, and several autoantibodies) and immunohistochemical (T lymphocyte subpopulations, B lymphocytes, natural killer cells, macrophages, immunoglobulin [Ig] G, Ig M, and C3c complement fraction) characteristics of vulvar lichen sclerosus. METHODS: Serum samples from 68 women with histologically proven lichen sclerosus were compared with those from 53 healthy controls, and tissue samples from 14 of 68 women chosen at random were compared with those from 14 of 53 healthy controls. A scoring system was constructed to compare the number of cells in the tissue. RESULTS: Patients had significantly lower counts of circulating lymphocytes CD3 and CD4 than controls (P < .05) and a higher number of autoantibodies (P < .01). Analysis of the tissue samples confirmed a lower number of CD2 cells (two-tailed P = .002 in epidermis, .005 in dermis), CD3 cells (two-tailed P = .001 in epidermis and in dermis), CD4 cells (two-tailed P = .002 in epidermis, .011 in dermis), and CD8 cells (two-tailed P = .002 in epidermis, .051 in dermis) in subjects than in controls. Numbers of monocyte-macrophage cells were similar in the epidermis but different in the dermis (two-tailed P = .003). No natural killer CD56 cells or B lymphocytes (CD19-CD21) were detected in the affected areas. Deposits of IgG, IgM, and C3 were no greater in biopsy specimens of patients than in those of controls. CONCLUSION: Vulvar lichen sclerosus is not caused by a T cell-mediated response, and a viral origin is unlikely. The absence of CD19 and CD21 cells excludes local production of autoantibodies. Our data do not confirm an autoimmune pathogenesis for vulvar lichen sclerosus but help explain why systemic cortisone is of no benefit and justify the use of petroleum jelly to relieve pruritus.

Adult↗

Levels of complement receptor type one (CR1, CD35) on erythrocytes, circulating immune complexes and complement C3 split products C3d and C3c are not changed by short-term physical exercise or training.

The effect of heavy short-term physical exercise on the levels of complement receptor type one (CR1, CD35) on erythrocytes, the concentrations of circulating immune complexes (IC), and the complement C3 split products C3c and C3d were examined in young healthy males. Fourteen untrained volunteers underwent a 60-min bicycle exercise test at 75% of maximal oxygen uptake (VO2max). Six of the volunteers were exercised twice with an interval of at least one month. Before the second bicycle test they received oral indomethacin. With an interval of at least 1 week, 6 also went through a 60-min back-muscle exercise at up to 30% of VO2max. Blood samples were collected before and during the last few minutes of exercise as well as 2 h and 24 h afterwards. The same parameters were examined once in 29 highly trained racing cyclists. There were no consistent or significant exercise-induced changes in the levels of erythrocyte CR1, circulating IC, C3c nor C3d as measured by an enzyme-linked immunosorbent assay, polyethylene glycol precipitation complement consumption method, and by intermediate gel rocket immunoelectrophoresis, respectively. Neither did these parameters differ from controls in the highly trained group. The results indicate that CR1 on erythrocytes, circulating immune complexes and complement cleavage products C3c and C3d in healthy subjects remain unaffected by short-term heavy physical activity and training.

Adult↗

[Concentrations of acute phase proteins in serum during the first two hours of hemodialysis using cuprophane and cellulose acetate dialyzers in patients with chronic renal failure].

In ten patients with chronic renal failure (CRF) serum concentrations of alpha 1-acid glycoprotein, alpha 1-antitrypsin, prealbumin, hemopexin, transferrin, haptoglobin, C3c and C4 complement components, ceruloplasmin, alpha 2-macroglobulin were determined using Partigen plates before, 30 min. and 2 hours after beginning of HD. Serum concentrations of C3c complement component, prealbumin increased significantly during HD using CU dialyser, but changes during HD using CA dialyser were not significant. Serum concentrations of alpha 1-antitrypsin, hemopexin increased significantly after two hours of HD using CA dialyser, but changes during HD using CU dialyser were again not significant. Serum concentrations of alpha 1-acid glycoprotein, transferrin, haptoglobin, ceruloplasmin, C4 complement component during HD using both dialyzers did not change significantly. Serum concentration of alpha 2-macroglobulin was higher after two hours of HD. The type of dialysis membrane has important influence on changes of serum acute phase proteins during the initial period of HD.

Acute-Phase Proteins↗