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PubMed1977

The effect of 2-deoxyglucose on guinea pig polymorphonuclear leukocyte phagocytosis.

The effects of 2-deoxyglucose (DOG), an inhibitor of glycolysis, on guinea pig polymorphonuclear leukocytes (PMN) obtained from peritoneal exudates was examined. ATP levels in PMN were reduced by 40% by one hour following an incubation with 2-deoxyglucose. When complement (C3) coated 14C-staphylococcus aureus, C3 coated lipopolysaccharide-paraffin oil droplets (LPS-PO), 14C-pneumococcus opsonized with IgG, or albumin coated paraffin oil droplets opsonized with IgG were added to cell suspensions containing DOG, the phagocytizing rate was 1,310+/-55 cpm/5 X 10(6) cells/15 minutes, 6+/-2 microng paraffin oil (PO)/10(7) cells/minute, 2,250+/-175 cpm/1 X 10(6) cells/20 minutes or 0.037+/-0.01 mg PO/10(7) cells/minute compared to control values of 5,970+/-275 cpm/5 X 10(6) cells/15 minutes, 35+/-3 microng PO/10(7) cells/15 minutes, 4,510+/-200 cpm/1 X 10(6) cells/20 minutes and 0.067+/-0.01 mg PO/10(7) cells/minute. In parallel studies the phagocytic index for latex was 0.74+/-0.28 in DOG compared to control of 2.36+/-1.13 and the phagocytic rate of albumin coated paraffin oil droplets was 0.029+/-0.01 mg PO/10(7) PMN/minute in DOG compared to control of 0.048 mg PO/10(7) cells/minute. When ATP levels were maintained by the simultaneous addition of 5 mM glucose or pyruvate to media containing DOG, latex ingestion was improved to 1.15+/-0.3 with glucose and 1.59+/-0.64 with pyruvate and albumin coated particles to 0.045+/-0.01 mg PO/10(7) PMN/minute with pyruvate. There was no improvement in the uptake of either the C3 dependent particles or IgG coated Pneumococci in media containing DOG and glucose and/or pyruvate. Following the removal of DOG from the extracellular medium and the addition of pyruvate or glucose, phagocytosis of C3 dependent LPS-PO was restored to normal values. Neither the binding of C3 or IgG coated particles to the PMN nor the lateral movement of glycoprotein utilizing concanavalin A capping was affected by DOG. Thus, the presence of DOG in the PMN containing adequate amounts of ATP will selectively and reversibly inhibit those surface events required for phagocytosis of C3 and IgG bound particles but not latex particles or albumin particles which non-specifically bind to PMN.

Adenosine Triphosphate↗
PubMed2005

TLR2 modulates inflammation in zymosan-induced arthritis in mice.

The interplay between the innate and acquired immune systems in chronic inflammation is not well documented. We have investigated the mechanisms of inflammation in murine zymosan-induced arthritis (ZIA) in the light of recent data on the roles of Toll-like receptor 2 (TLR2) and Dectin-1 in the activation of monocyte/macrophages by zymosan. The severity of inflammation, joint histology, lymphocyte proliferation and antibody production in response to zymosan were analyzed in mice deficient in TLR2 and complement C3, and the effects of Dectin-1 inhibition by laminarin were studied. In comparison with wild-type animals, TLR2-deficient mice showed a significant decrease in the early (day 1) and late phases (day 24) of joint inflammation. C3-deficient mice showed no differences in technetium uptake or histological scoring. TLR2-deficient mice also showed a significant decrease in lymph node cell proliferation in response to zymosan and a lower IgG antibody response to zymosan at day 25 in comparison with wild-type controls, indicating that TLR2 signalling has a role in the development of acquired immune responses to zymosan. Although laminarin, a soluble beta-glucan, was able to significantly inhibit zymosan uptake by macrophages in vitro, it had no effect on ZIA in vivo. These results show that ZIA is more prolonged than was originally described and involves both the innate and acquired immune pathways. C3 does not seem to have a major role in this model of joint inflammation.

Animals↗
PubMed1980

[immunohistologic findings of kidney biopsies in Wilson's disease].

12 patients with Wilson's disease were examined by means of renal biopsy. In 9 of these patients a slight (4 patients) or a strong proteinuria (5 patients) appeared during the therapy with D-penicillamine. A biopsy was performed in 3 patients before the beginning of the therapy with D-penicillamine. The patients with severe proteinuria showed the largest immunohistological changes (partly distinct immune complex nephritis with epimembranous IgG- and complement-(C3-) depositions -- electronoptically membranous glomerulonephritis. In rebiopsy after a stoppage of the medicament of 1 year only a slight tendency to improvement was to be recognized.

Biopsy↗
PubMed1978

Relationship between Epstein-Barr virus (EBV)-production and the loss of the EBV receptor/complement receptor complex in a series of sublines derived from the same original Burkitt's lymphoma.

Virus production, EBV (P3HR-1 substrain) superinfectability, IdUrd inducibility, EBV receptor and complement (C3) receptor expression were assessed in two independently maintained jijoye lines, the derived P3HR-1 clone that releases a growth inhibitory and cytopathic, non-transforming viral mutant, and in non-producer sublines derived from the P3HR-1 line by the spontaneous cessation of virus production. Both jijoye lines were superinfectable, inducible, and carried EBV and C3 receptors. Virus-producing P3HR-1 cells and recently derived non-producer sublines lacked EBV-receptors and C3 receptors, could not be superinfected, but were IdUrd inducible. Two long-passaged, non-producer sublines of P3HR-1 reexpressed EBV and C3 receptors to an equal degree (different in the two sublines). EBV-superinfectability became partially reestablished in the subline with the higher expression of EBV and C3 receptors. These findings support the hypothesis that the EBV-receptor/C3 receptor negativity of the producer P3HR-1 sublines and their recent non-producer derivatives is due to negative selection by the growth-inhibitory, cytopathic P3HR-1 virus variant. The closely linked disappearance and reappearance of EBV-receptors and complement receptors gives further support to the idea that these two receptors are either identical or closely linked constituents of the cell membrane.

Antigens, Viral↗
PubMed1982

Combined immunomorphological examination of epon-embedded human kidney biopsies: a comparative study between cryostat, paraffin and consecutive epon-embedded sections for detection and localization of immune deposits.

Immunomorphologic analysis of glomerulopathies in human kidney biopsies can be achieved in sections embedded in Epon. Formalin fixation followed by protease treatment of the tissue before dehydration and embedding are the essential steps in the incubation method which permit the detection of both immunoglobulins and complement (C3). The sections can be used for comparative light, phase contrast, and electron microscopic examination. This method is superior to paraffin and methacrylate embedding techniques for detailed immunomorphology.

Basement Membrane↗
PubMed1979

Adherence, augmented adherence, and aggregation of polymorphonuclear leukocytes.

Adherence of polymorphonuclear leukocytes to nylon fiber was found to be plasma-independent and distinct from the processes of augmented adherence, leukocyte aggregation, and inhibition of random leukocyte migration, all of which are dependent on "activated" plasma. Nylon fibers were unable to "activate" plasma, in contrast to the complement-activating agent zymosan. Prior incubation of plasma with antiserum to the third component of complement (C3) inhibited aggregation of polymorphonuclear leukocytes by plasma incubated with zymosan, and heat-inactivation blocked augmentation of adherence by treatment of plasma with zymosan.

Adult↗
PubMed2006

Complement as a predictor of further miscarriage in couples with recurrent miscarriages.

BACKGROUND: The clinical significance of complement is unclear in patients with unexplained recurrent miscarriage, though low levels of complement 3 (C3) and/or complement 4 (C4) are reported to be associated with the antiphospholipid syndrome (aPS). We therefore investigated whether C3 and C4 have a predictive value for subsequent miscarriages. METHODS: In total, 215 patients with a history of two consecutive first-trimester miscarriages and no abnormal chromosomes in either partner, no uterine anomalies and no antiphospholipid (aPL) antibodies were examined. Blood tests for C3, C4, total haemolytic complement (CH50), immunoglobulin G (IgG), immunoglobulin A (IgA) and immunoglobulin M (IgM) were performed before subsequent pregnancy. Patients were then followed up without treatment, and their pregnancy outcomes were compared with their previous blood test results. RESULTS: From 215 pregnant patients, 45 subsequently miscarried, whereas the remainder had a live birth. There was no relation with serum CH50, IgG, IgA and IgM levels, but C3 and C4 levels in patients with subsequent miscarriage were significantly higher than in those whose pregnancy was successful. CONCLUSION: In patients with two previous miscarriages, C3 and C4 levels were higher in those women who had a third miscarriage, than in women that went on to have a live birth.

Abortion, Spontaneous↗
PubMed1994

Third component of complement serum levels in dogs with leishmaniasis.

Radial immunodiffusion was used to determine the concentration of the third component of complement (C3) in the serum of 51 adult dogs with leishmaniasis and, for comparative purposes, in a control group of 30 healthy dogs. Animals in both groups were of different age, sex and breed. The mean concentration in healthy dogs was 93.3 +/- 6.6 (mean +/- SD), and in sick dogs 131.4 +/- 7.1, both expressed as a percentage of a reference standard. Statistically significant differences (P < 0.0004) were found between serum C3 concentrations in leishmania-infected and control groups, but no significant difference was recorded between males and females in either group.

Animals↗
PubMed1989

Ontogeny of the third component of complement in neonatal swine.

Ontogeny of the third component of complement (C3) was monitored in 10 neonatal swine, using a radial immunodiffusion technique. Significant differences in mean serum C3 concentrations, expressed as percentage of C3 concentration in a pooled standard drawn from 15 adult swine, were not observed between serum samples collected before pigs suckled and at 2 days of age (P = 0.2583). Serum C3 concentrations increased significantly between 2 and 7 days of age (P less than 0.0001) and 7 and 14 days of age (P less than 0.0001). Concentrations comparable with those in adults were observed at 14 days of age and significant changes were not observed thereafter. Acquisition of adult concentrations of C3 appeared to be a function of endogenous production by the neonate, rather than by passive colostral transfer.

Animals↗
PubMed2006

Factor B of the alternative complement pathway regulates development of airway hyperresponsiveness and inflammation.

Exposure to inhaled allergens leads to increases in airway hyperresponsiveness (AHR) and inflammation, associated with increased levels of biologically active fragments derived from the complement C3 and C5 family of proteins. Further, complement activation during allergen challenge in sensitized animals is necessary for the development of AHR and airway inflammation. To define the complement pathway involved, we studied mice deficient in complement factor 4 (C4-/-), a critical component of the classical pathway, or factor B (fB-/-), an essential protein in the alternative complement pathway. WT, C4-/-, and fB-/- mice were sensitized to ovalbumin and subsequently exposed to nebulized ovalbumin (1% in saline) on 3 consecutive days. After allergen sensitization and challenge, fB-/- mice demonstrated significantly lower airway responsiveness to methacholine and less airway inflammation. In contrast, C4-/- mice showed no reduction in AHR and airway inflammation compared with WT mice. Tissue inflammation, goblet cell hyperplasia, and IL-4, IL-5, and IL-13 levels in BAL fluid were significantly reduced in fB-/- mice compared with C4-/- and WT mice. The development of AHR and airway inflammation in sensitized fB-/- mice could be restored after intranasal administration of purified factor B before the airway challenge. In addition, administration of a neutralizing anti-factor B mAb to sensitized mice before airway challenge reduced the development of AHR and airway inflammation. These results demonstrate that in sensitized hosts complement activation through the alternative pathway after allergen exposure is critical to the development of AHR and airway inflammation.

Animals↗
PubMedDate not supplied

Protective effect of nafamostat mesilate on injury of porcine hepatocytes by human plasma.

Nafamostat mesilate (NM), a protease inhibitor, possesses a cytoprotective effect and inhibits the activation of complement. The present study investigated whether NM has any protective effect against injury of porcine hepatocytes by human plasma in a bioartificial liver support system. Porcine hepatocytes were harvested and seeded at a density of 2 x 10(5) cells on a 35-mm collagen-coated plate in Dulbecco's modified Eagle's medium (DMEM) with 10% fetal calf serum. Twenty-four hours later, the medium was replaced with human plasma with three concentrations of NM between 3.8 x 10(-5) and 3.8 x 10(-4) M and then cultured for 6 h. The viability of porcine hepatocytes, lactate dehydrogenase (LDH) levels, lidocaine clearance, porcine albumin production, and changes in complement (C3) levels were measured. The viability of porcine hepatocytes in human plasma decreased significantly to 37.7 +/- 11.4% of that in DMEM. NM improved the viability of the hepatocytes, lowered the levels of LDH, and increased lidocaine clearance and albumin production in a concentration-dependent manner. The concentrations of C3, the marker of xenogeneic reactions, did not change significantly, indicating that no hyperacute xenogeneic reaction occurred in our series. Together, our results suggested that NM exerts favorable effects on porcine hepatocytes in human plasma through direct effect such as prevention of protease activity in the plasma membrane of porcine hepatocytes rather than inhibition of complement-dependent immunoreactions.

Albumins↗
PubMed1975

Evaluation of the plasma kinin system in dengue hemorrhagic fever.

The role of the plasma kinin system in the pathogenesis of dengue hemorrhagic fever (DHF) ws explored by simultaneously measuring factor XLL (Hageman), prekallikrein, kallikrein inhibitors, bradykinin, and complement (C3) in the blood of Thai children with DHF and acute febrile illnesses other than dengue. Prekallikrein, factor XII, and C3 levels were significantly lower in DHF patients compared to fever control patients with the lowest mean levels found in dengue patients with shock. However, bradykinin concentrations were not elevated and mean activity levels of kallikrein inhibitors were not depressed in dengue patients. Two dengue patients first studies at least 2 days before onset of shock had falling C3 levels which were more closely related temporally to the onset of shock than were their rising levels of prekallikrein. The results fail to provide convincing evidence ofr activation of the plasma kinin system leading to free bradykinin or a significant role for bradykinin in the immunopathogenesis of DHF. By contrast, the results refocus attention on complement as a potentially important humoral mediator of the dengue shock syndrome.

Antigens, Viral↗
PubMed1990

Reduction of complement activation in rheumatoid arthritis by steroid treatment.

Patients with severe active active rheumatoid arthritis (RA) have higher than normal plasma concentrations of the complement C3 split-product C3d, indicating increased complement activation. Treatment with steroids reduced plasma C3d levels in these patients. Ten patients with classic or definite RA and high disease activity were studied during six days of treatment with steroids. The C3d plasma concentrations declined in a dose-related manner with an increase in daily prednisolone dosage. However the statistical significance of this relationship did not seem to be high enough to validate the use of serial C3d estimations to monitor changes in disease activity in RA patients during short-term steroid treatment.

Arthritis, Rheumatoid↗
PubMed2002

[Humoral and cellular immunity investigation in idiopathic uveitis].

OBJECTIVES: There is an amount of controversy regarding the patho-physiology of uveitis. Due to the fact that the eye (and especially the highly vascular tissues such as the uvea and the conjunctiva) is considered a special "target" for the immunopathologic reactions, the goal of our study is to contribute to the understanding of the causal role of the immune reactions in the development of idiopathic uveitis. MATERIAL AND METHODS: We have studied 48 patients with idiopathic uveitis and 20 control subjects (with no ocular symptomatology) for the following humoral and cellular immune markers: IgM and IgG, the C3 complement fraction, circulating immune complexes, autoantibodies (antinuclear autoantibodies, anti-double stranded DNA autoantibodies, anti-smooth muscle autoantibodies, anti-neutrophilic cytoplasm autoantibodies, anti-cardiolipin autoantibodies, anti-parietal cell autoantibodies), and lymphocyte subtypes. RESULTS: Changes in the serum levels of the immune humoral and cellular markers have been noted in 39 (81.25%) of the patients studied. C3 was decreased in 12 (30%) of all cases; the immune complex level was increased over 50 U/mL in 20 patients (51.28%). The presence of the above-mentioned autoantibodies was seen in 19 patients (48.71%), with different incidence. By flow cytometry the percentage of CD4+ (T helper lymphocytes) has been found to be decreased, and the percentage of CD8+ was found to be increased in 8 cases (20.51%). The opposite, the increase in the percentage of CD4+ lymphocytes, and the decrease in the percentage of CD8+ cells was seen in 25 (64.10%) of the studied patients. Taking into consideration the clinical symptoms and the level of the immune humoral and cellular parameters, the cases included in the study have been included in two groups: anterior uveitis (acute and chronic), and posterior uveitis. CONCLUSIONS: By comparing the results, we conclude that the autoimmunity and the immediate hypersensitivity mediated by immune complexes may be involved in the appearance and the development of the intraocular inflammation in certain cases of idiopathic uveitis.

Adult↗
PubMed1992

Renal involvement in mice experimentally infected with Toxocara canis embryonated eggs.

Histological examination of kidneys from mice experimentally infected with Toxocara canis embryonated eggs demonstrated the presence of a segmental or diffuse mesangioproliferative glomerulonephritis. Immunohistochemical studies established that renal alterations were associated with glomerular deposits of IgG, IgM and third component of complement (C3). These findings suggest that an immunomediated mechanism might possibly be involved in the genesis of kidney damage observed in mice infected with T. canis embryonated eggs.

Animals↗
PubMed1981

Deposits of immunoglobulins, complement, and fibrinogen in oral lupus erythematosus, lichen planus, and leukoplakia.

Direct immunofluorescent staining (IF) for detection of deposits of IgG, IgM, IgA, complement C3, and fibrinogen at the basement membrane zone has been performed on a total of 279 biopsy specimens from oral lesions and clinically normal oral mucosa from the following groups of patients: fourty-five discoid lupus erythematosus (DLE), including sixteen patients without skin lesions, seven systemic lupus erythematosus (SLE); fourty-five lichen planus (LP); thirty leukoplakia (Leuk.); twenty patients with uncertain diagnosis, termed DLE? LP?; and twenty-three healthy persons. Deposits of immunoglobulins (lg) occurred in 73 percent of oral lesions in DLE and in 100 percent of the oral lesions in SLE, whereas lg deposits occurred in 3 to 30 percent in the other groups, the differences being significant (P less than 0.05). It is concluded that lg deposits are a characteristic feature of oral lesions of DLE and SLE and only rarely occur in oral lesions of LP and Leuk., which are the most important differential diagnoses. A direct immunofluorescence test on oral lesions suspected to be LE should be regarded as positive only if lg deposits are present, since C3 occurs frequently in oral lesions other than LE. Consideration can be given to the inclusion of lg deposits in the diagnostic criteria for oral LE lesions.

Adolescent↗
PubMed1976

Identification of T and B cell subpopulations in human peripheral blood: electrophoretic mobility distributions associated with surface marker characteristics.

The electrophoretic mobility distributions of human peripheral blood lymphocytes isolated on Ficoll-Hypaque gradients were characterized by laser Doppler spectroscopy. Three major subpopulations were spectrally resolved, due to differences in their mobility, when an electric field was applied to the scattering cuvette. The fastest component (centered at 2.35 mum/sec/V/cm for 25 degrees C, 0.28 M sucrose medium of 0.005 ionic strength) passed through nylon fiber columns and was identified as a T cell subpopulation. The slowest component (1.85 mum/sec/V/cm) which was further enriched by a one-step rosette procedure with sheep erythrocytes, reacted with activated-complement (C3) and antiserum to human immunoglobulins and was therefore identified as a B cell subpopulation. The intermediate component (centered at 2.15 mum/sec/V/cm) appears to be another T cellsubpopulation. Although cells of this component did not pass through nylon fiber columns, they did rosette with sheep erythrocytes. Furthermore, these cells did not appear to have surface immunoglobulins or complement receptors.

Antibodies, Anti-Idiotypic↗