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PubMed1999

Spatial arrangement of subepithelial deposits in lupus and nonlupus membranous nephropathy.

Subepithelial deposits are a common feature of idiopathic membranous glomerulonephritis (MGN) and lupus membranous glomerulopathy (LMGN). We investigated the spatial arrangement of immunoglobulin G (IgG) and C3c fraction of complement (C3c) in the immune deposits of MGN and LMGN with confocal laser scanning microscopy to correlate specific patterns of IgG-C3 interactions with different diseases. Ten patients with MGN and 8 patients with LMGN (World Health Organization class VB) were selected. A determination of the spatial arrangement of the two fluorochromes and the glomerular area occupied by each fluorochrome was performed for each case. Our results showed MGN specimens have an orderly distribution of IgG and C3c, with each deposit showing an outer ring of sole IgG. IgG was always more abundant than C3c (1,619 +/- 271 v 790 +/- 105 micrometer(2), P = 0.002). In LMGN, IgG and C3c were haphazardly arranged, with deposits made of C3c only and an outer ring of IgG only rarely present. Also, the relative amounts of the two antigens were variable, and two groups could be identified (group 1: IgG, 5,515 +/- 1,179 micrometer(2) v C3c, 4,810 +/- 1,174 micrometer(2); P = 0.02; group 2: IgG, 3,358 +/- 658 micrometer(2) v C3c, 4,047 +/- 740 micrometer(2); P = 0.03). Our data show that diffuse IgG capping of the subepithelial immune deposits is diagnostic of MGN. The absence of an orderly three-dimensional arrangement in LMGN deposits (ie, outer ring of IgG) is likely to render active complement components more readily available to inflammatory activities.

Adult↗
PubMedDate not supplied

Birmingham vasculitis activity score, disease extent index and complement factor C3c reflect disease activity best in hepatitis C virus-associated cryoglobulinemic vasculitis.

OBJECTIVE: Clinical measures of vasculitis activity (Birmingham vasculitis activity score = BVAS) and disease extent (Disease Extent Index = DEI), serological and immunological parameters were evaluated for the monitoring of hepatitis C virus (HCV)-associated cryoglobulinemic vasculitis (CV), treated with either cyclophosphamide or interferon-alpha 2b depending on disease severity. METHODS: Serial serum samples of 15 patients with HCV-associated CV were analyzed, and BVAS, DEI, serological and immunological parameters were recorded at diagnosis and during therapy. Eight patients were treated with interferon-alpha 2b and 7 patients with cyclophosphamide. RESULTS: A complete or partial response of the CV was seen in both treatment groups. BVAS, complement factor C3c, cryoglobulinemia, and rheumatoid factor significantly decreased in both treatment groups during 6 months (p < 0.05). DEI decrease was significant in the cyclophosphamide group (p < 0.05), and there was a trend in the interferon-alpha 2b group (p = 0.06). BVAS and DEI were significantly positively correlated, and both parameters were significantly negatively correlated with C3c levels in both treatment groups (interferon-alpha 2b/cyclophosphamide: r = -0.89, p = 0.001 versus r = -0.87, p < 0.001, respectively) whereas other parameters were not, e.g. ESR and CRP. CONCLUSIONS: Patients with different degrees of disease severity, treated with either cyclophosphamide or interferon-alpha 2b depending on their disease activity, achieved remission of their CV. BVAS, DEI and C3c were especially useful in the follow-up of HCV-associated CV. C3c correlated with BVAS and DEI during therapy and provided additional information about vasculitis activity that was not reflected by other serological or immunological parameters, e.g. ESR or CRP.

Adult↗
PubMed1981

Cleavage of membrane bound C3bi, an intermediate of the third component of complement, to C3c and C3d-like fragments by crude leucocyte lysosomal lysates and purified leucocyte elastase.

Partial degradation of the biologically-active major fragment of the third complement component (C3b) to C3bi is catalysed by the endopeptidase C3b inactivator (I) and its co-factor, beta 1H globulin (H). Complete degradation to the fragments C3c and C3d requires an additional protease, which can be simulated in vitro by trypsin. This study was designed to identify the in vivo correlate of trypsin. Purified and 125I-labelled C3b bound to sheep erythrocytes was used as substrate. Release of label into the supernate served as an index of proteolysis. The chain structure of the peptides in the supernate or remaining bound to the erythrocytes was assessed by SDS polyacrylamide gel electrophoresis. Significant cleavage of cell-bound C3b was obtained by treatment with I, H and extracts from human peripheral blood leucocyte azurophil granules. Purified elastase also removed label in the presence of I and H. The peptide remaining on the cell had the characteristic 33K molecular weight of C3d. The activity of elastase in cleaving was blocked by alpha-1-anti-trypsin, the chloromethyl ketone, MeO-Suc-Ala-Pro-Val-Ch2Cl and by rabbit antibody to elastase. Thus, elastase purified from azurophil granules of human polymorphonuclear neutrophils (PMN) is a potent catalyst of the cleavage of C3bi to C3c- and C3d-like fragments and may contribute in vivo to the control of complement-mediated inflammation.

Animals↗
PubMed1999

Inflammation and intracranial aneurysms.

OBJECTIVE: An intracranial aneurysm is an important acquired cerebrovascular disease that can cause a catastrophic subarachnoid hemorrhage. Despite modern therapy, most patients die or are left disabled as a direct result of a severe initial hemorrhage. The development of more effective treatment strategies depends on understanding the fundamental biology of cerebral aneurysms. The purpose of the present study is to determine whether inflammation or immunological reaction occurs in cerebral aneurysms. METHODS: Aneurysm tissue was collected at the time of microsurgical repair from 23 unruptured and 2 ruptured aneurysms (25 patients) and compared with 11 control basilar arteries harvested at autopsy. Immunohistochemistry was used to localize complement (C3c, C9), immunoglobulins (IgG, IgM), vascular cell adhesion molecule-1, macrophages and monocytes (CD68), T lymphocytes (CD3), and B lymphocytes (CD20). RESULTS: Complement (C3c, P < 0.0001; C9, P = 0.0017), immunoglobulin (IgG, P = 0.0013; IgM, P = 0.031), vascular cell adhesion molecule-1 (P = 0.0022), macrophages (CD68, P = 0.004), and T lymphocytes (CD3, P = 0.0004) were all frequently present in the wall of aneurysm tissue but were rarely identified in control basilar arteries. A few B lymphocytes (CD20, P = 0.41) were found in aneurysm tissue, but none were found in the basilar arteries. CONCLUSION: Extensive inflammatory and immunological reactions are common in unruptured intracranial aneurysms and may be related to aneurysm formation and rupture.

Adult↗
PubMed1985

Familial occurrence of complement dysfunction in Crohn's disease: correlation with intestinal symptoms and hypercatabolism of complement.

Complement was studied in Crohn's disease probands with early onset and in their first degree relatives. Controls included 24 healthy volunteers and 24 patients with ulcerative colitis or peptic ulcers. Subnormal generation of chemotactic activity by the alternative pathway was shown in eight of 21 probands and in six of 33 relatives, a frequency in both groups significantly different from controls (p less than 0.005), with a strong connection between findings in patients and relatives. As previously shown in patients with Crohn's disease, the subnormal generation was related to decreased utilisation of complement C3 in relatives. Raised levels of circulating complement C3c split products suggested complement involvement in Crohn's disease probands. In contrast, plasma C3c was normal in all relatives, and none of the six cases with complement dysfunction had gastrointestinal symptoms or a history of inflammatory bowel disease. Our data suggest, that complement abnormality seen in Crohn's disease patients does not simply reflect mucosal inflammation or hypercatabolism of complement.

Adolescent↗
PubMed1991

Failure to detect deposition of complement and immunoglobulin in allergen-induced late-phase skin reaction in atopic subjects.

There still remains some controversy regarding the possible role of immune complexes in the pathogenesis of the late-phase skin reaction (LPSR). To assess this, skin biopsies were obtained from LPSR induced in atopic human subjects 6, 24 and 48 h after allergen challenge. Cryostat sections were stained by direct immunofluorescence for the presence of fibrinogen, immunoglobulin classes IgM and IgG and for the complement components C1q and C3c. Complement components were observed in only two of the 29 biopsies studied. In both instances, only C3c was detected. One of these subjects also had unequivocal IgG staining at 6 h. IgM staining was detected in two out of 10 subjects at 6 h but no significant deposition of immunoglobulins could be found at 24 or 48 h. Fibrinogen deposition was observed in about half of the biopsies at each time-point. This study suggests that substantial complement and immunoglobulin deposition are not overt features of the allergen-induced LPSR, although the presence of small amounts of immune complexes, below the sensitivity of the method employed cannot be excluded. Fibrin deposition occurs in the LPSR but does not appear to be a prerequisite for LPSR development.

Allergens↗
PubMed1989

[Serum levels of acid alpha 1-glycoprotein, haptoglobin, C 3c component of the complement and immunoglobulins IgG, IgA and IgM in liver damage in patients with chronic renal failure treated by repeated hemodialysis].

Thirty-five patients with chronic renal failure treated with repeated haemodialyses were divided into 3 groups: without evidence of hepatocellular damage (n = 11), with HBs-negative hepatocellular damage (n = 13), with HBS-positive, HBe-positive hepatocellular damage (n = 10). The concentrations of acid alpha 1-glycoprotein, haptoglobin, C3c complement component, IgG, IgA, IgM were determined in the serum before haemodialysis. The serum concentration of acid alpha 1-glycoprotein was statistically significantly higher in the patients in comparison with the healthy subjects. The concentrations of haptoglobin and C3c complement component in the serum were not statistically significantly different form those in healthy controls. The serum levels of IgG, IgA and IgM in patients with hepatocellular damage HBs-positive and HBe-positive were statistically significantly higher in relation to healthy subjects, the serum IgG level in this group was statistically significantly higher than in the group without hepatocellular damage and the group with HBs-negative hepatocellular damage.

Adult↗
PubMed1987

Enrichment of subgingival microflora on human serum leading to accumulation of Bacteroides species, Peptostreptococci and Fusobacteria.

This study was undertaken to identify ecological factors that favour opportunistic pathogenic species in the subgingival microflora. In a first approach, human serum as a substitute for gingival exudate, was used for batch-wise enrichment of subgingival plaque. The microflora resulting after 5-6 enrichment steps consisted of black-pigmented and non-black-pigmented Bacteroides species, Peptostreptococcus micros and Fusobacterium nucleatum as the main organisms. It is noted that the same group of species was found to be enriched independent upon the origin of the subgingival plaque sample. It was suggested that these organisms are favoured by the increased flow of gingival exudate during inflammation. The consortium of organisms was capable of selective degradation of serum (glyco-)proteins. Four different types of degradation occurred. After a prolonged period of growth complete degradation of immunoglobulins, haptoglobin, transferrin and complement C3c was observed. Partial degradation of immunoglobulins, haptoglobin, transferrin, albumin, alpha 1-antitrypsin and complement C3c and C4 was generally observed after 48 h of growth. Besides, immunoglobulin protease activity yielding Fc and Fab fragments was found. The consortium was also capable of consuming carbohydrate side-chains as indicated by an altered electrophoretic mobility of the serum glycoproteins.

Bacteroides↗
PubMed2004

Enhanced phagocytosis of ring-parasitized mutant erythrocytes: a common mechanism that may explain protection against falciparum malaria in sickle trait and beta-thalassemia trait.

High frequency of erythrocyte (red blood cell [RBC]) genetic disorders such as sickle cell trait, thalassemia trait, homozygous hemoglobin C (Hb-C), and glucose-6-phosphate dehydrogenase (G6PD) deficiency in regions with high incidence of Plasmodium falciparum malaria and case-control studies support the protective role of those conditions. Protection has been attributed to defective parasite growth or to enhanced removal of the parasitized RBCs. We suggested enhanced phagocytosis of rings, the early intraerythrocytic form of the parasite, as an alternative explanation for protection in G6PD deficiency. We show here that P falciparum developed similarly in normal RBCs and in sickle trait, beta- and alpha-thalassemia trait, and HbH RBCs. We also show that membrane-bound hemichromes, autologous immunoglobulin G (IgG) and complement C3c fragments, aggregated band 3, and phagocytosis by human monocytes were remarkably higher in rings developing in all mutant RBCs considered except alpha-thalassemia trait. Phagocytosis of ring-parasitized mutant RBCs was predominantly complement mediated and very similar to phagocytosis of senescent or damaged normal RBCs. Trophozoite-parasitized normal and mutant RBCs were phagocytosed similarly in all conditions examined. Enhanced phagocytosis of ring-parasitized mutant RBCs may represent the common mechanism for malaria protection in nonimmune individuals affected by widespread RBC mutations, while individuals with alpha-thalassemia trait are likely protected by a different mechanism.

Adult↗
PubMedDate not supplied

Effects of environmental tobacco smoke on serum levels of acute phase proteins in schoolchildren.

BACKGROUND: Few biological changes due to long-term exposure to environmental tobacco smoke (ETS) have been identified. This study examined the relationship between exposure to ETS and serum levels of acute phase proteins among children. METHODS: The concentrations of the third component of complement (C3c), haptoglobin (Hp), alpha 1 acid glycoprotein (alpha 1AG), and ceruloplasmin (Cp) were determined in serum samples obtained from 480 school-children. Exposure to ETS was assessed from responses to questionnaires. RESULTS: Serum levels of C3c, Hp, and alpha 1AG were significantly higher among boys living in households in which there were smokers other than their parents than among boys with no smokers in their family or those in households were only the father smoked. Levels of C3c, Hp, and alpha 1AG in relation to the level of ETS exposure were significantly increased among boys exposed to ETS of 11 or more cigarettes per day. Among girls, increased alpha 1AG levels were associated with exposure to high levels of ETS, but no differences were found in any of the other proteins. Cp levels were not affected by exposure to ETS among either boys or girls. CONCLUSIONS: These findings suggest that the serum levels of C3c, Hp, and alpha 1AG among schoolchildren may reflect different levels of exposure to ETS. Boys seemed to be more susceptible to ETS exposure than girls.

Acute-Phase Proteins↗
PubMed1998

Complement activation during blood sampling procedures alters the expression of CD11b/CD18 on human neutrophils.

BACKGROUND AND OBJECTIVES: Differences in blood sampling and separation techniques can affect the quantitative levels of activation markers on different leukocyte subsets. We examined the effect of two sampling procedures of EDTA blood on the quantitative levels of two markers, the CD11b/CD18 antigen and the EG2 epitope on intracellular eosinophilic cationic protein (ECP), in neutrophils and eosinophils, respectively. MATERIALS AND METHODS: Sample I was collected directly after completion of blood donation by an open technique and constant flow from the transfer tube directly into EDTA tubes. After sampling, the transfer tube was manually closed with a clamp. Sample II was collected 45 s later by the same technique by opening the clamp. RESULTS: We found a significantly (p < 0.01) higher expression of CD11b/CD18 on neutrophils collected by sampling procedure II than on those collected by sampling procedure I. In contrast, we did not find any difference in the intracellular ECP expression between sampling procedures I and II. To further explore the mechanisms for the observed upregulation of CD11b/CD18, fragments of a transfer tube were incubated with normal human serum (NHS) and heat-inactivated NHS (NHS56), respectively, for 60 min at +37 degrees C. Leukocytes from healthy blood donors were then incubated for 15 min at +37 degrees C with these serum preparations. The CD11b/CD18 expression was significantly higher (p < 0.01) on neutrophils incubated with transfer-tube-activated NHS compared with NHS alone. However, when leukocytes were incubated with transfer tube activated NHS56, no difference was observed compared with incubation with NHS alone. In addition, by using confocal laser scanning microscopy, we could identify complement (C3c) deposits on the inner surface of the transfer tube fragments incubated in NHS, but not in NHS56, CONCLUSIONS: The quantitative level of the activation marker CD11b/CD18 on neutrophils, but not the EG2 epitope on intracellular ECP in eosinophils is significantly increased by a slight modification of the blood sampling procedure. It is suggested that the observed upregulation of CD11b/CD18 is caused by complement activation within the transfer tube. The results emphasize the importance of in-house data on the effect of variations in sampling procedures, particularly when data from healthy blood donors are included in clinical studies.

Blood Proteins↗
PubMedDate not supplied

Acute haemolysis in childhood falciparum malaria.

Acute haemolysis associated with clinical episodes of high-level Plasmodium falciparum parasitaemia was studied in 20 children from an holoendemic area (coastal Tanzania). The change in blood haemoglobin (Hb) concentration ranged from -46 to g/L during the 72-h observation period and was linearly related to maximum parasitaemia. Balance studies between loss of blood Hb, increase in plasma Hb and appearance of Hb in the urine indicated that extravascular clearance of red cells was the predominant mode of erythrocyte clearance. Most subjects, however, showed minor signs of intravascular haemolysis. The plasma Hb was << 1% of blood Hb and haemoglobinuria was detected in 14/20 children but the excretion of Hb in urine was < 0.5% of total Hb loss. Haemoglobinuria was, however, a marker of severe haemolysis, since the maximum blood Hb loss in children without haemoglobinuria was 10 g/L. Erythrocyte-bound opsonins known to induce erythrophagocytosis, i.e., complement C3c fragments and autologous IgG, were increased in all patients. In the patients with major haemolysis, the changes correlated to the haemolysis over time. Hence, a similar mechanism for predominantly extravascular erythrocyte clearance may be operative in acute malarial anaemia, normal erythrocyte senescence and other forms of acute haemolysis.

Acute Disease↗
PubMed1984

Changes in soluble proteins in cervical mucus during midcycle in normally menstruating women.

Albumin, IgG and complement C3c were analyzed by immunonephelometry in cervical mucus collected daily at midcycle. There was a statistically significant difference in the amount of mucus recovered on the day of the luteinizing hormone (LH) surge and on the following day. Several nadirs in protein concentration could be visualized in 8 out of 14 subjects, whereas in 6 subjects, no such changes in concentration were found. In terms of soluble protein concentrations and amounts there were no differences between cycle days. For changes in soluble protein concentrations and amounts, no systematic time relation to the LH peak could be found.

Adult↗
PubMed1997

Serum protein leakage in Alzheimer's disease revisited.

Leakage of serum proteins into the brain parenchyma has been repeatedly used as evidence of blood-brain barrier (BBB) damage in experimental and human studies. However, there is no consensus in the literature concerning this phenomenon in Alzheimer's disease (AD). We have examined this question by comparing frontal lobe sections in seven groups of patients: Multi-infarct dementia (n = 6), AD with (n = 10) and without (n = 10) infarcts, age-matched controls with (n = 10) and without (n = 10) infarcts, controls with neurodegenerative diseases other than AD, and young controls (n = 10). An additional series compared prospectively followed patients with a diagnosis of either multi-infarct dementia (n = 5) or AD (n = 4). Albumin was detected in white-matter astrocytes in all cases, without significant variation in intensity. In addition, diverse combinations of neurons, astrocytes, and (in AD patients) senile plaques were present in the cerebral cortex in an inconsistent manner. Semiquantitative analysis showed no statistically significant differences among groups. Anti-IgG labeled astrocytes in infarcts only. Complement C3c component was detected in rare amyloid plaques in a minority (15%) of AD cases. Selective labeling of AD-specific lesions in a patchy manner was observed for serum amyloid P. We conclude that there is no immunohistochemical evidence of alteration of the BBB in Alzheimer's disease with or without vascular factors or in old age. Serum amyloid P binds avidly to AD lesions, but our findings are consistent with leakage through the BBB during the agonal or immediate postmortem period. Finally, no specific pattern of abnormality in the BBB was detected in multi-infarct dementia.

Alzheimer Disease↗
PubMed2003

Human alpha galactosidase and alpha 1,2 fucosyltransferase concordantly inhibit xenoreactivity of NIH 3T3 cells with human serum.

AIM: To study the influence of the expression of human alpha galactosidase and alpha1,2 fucosyltransferase on Gal alpha 1,3 Gal and consequent xenoreactivity in NIH3T3 cells. METHODS: The expression levels of G antigen and H antigen and binding of human natural antibodies (IgG and IgM) and complement (C3c) to NIH3T3 cells were analyzed by flow cytometry. Western blot was employed to further determine the expression of glycoproteins of G antigen. Cytolysis assay with normal human serum was performed by MTT assay. RESULTS: Western blot showed that glycoproteins with molecular weight of 107 kDa, 98 kDa, 88 kDa, 56 kDa, 40 kDa, and 37 kDa were inhibited and even abrogated totally in alpha galactosidase transfectants and alpha 1,2 fucosyltransferase transfectants. The combined transfection of the two enzymes led to a much stronger inhibition of the glycoproteins. The binding of GS-IB4 was decreased by 57.4 % in alpha galactosidase transfectants, 28.8 % in alpha 1,2 fucosyltransferase transfectants, and 72.1 % in combined transfectants, respectively. In contrast, UEA-1 binding was increased about 6.7-fold, 6.0-fold, and 8.0-fold respectively. The xenoreactivity with human IgG was also reduced by 61.4 %, 67.0 %, and 73.4 %, respectively in the three kinds of transfectants. The resistance to cytolysis mediated by human serum was enhanced by 42.4 % in alpha galactosidase transfectants, 51.9 % in alpha 1,2 fucosyltranferase, and even 65.5 % in the combined transfectants. CONCLUSION: Although alpha galactosidase and alpha 1,2 fucosyltransferase had different biochemical properties, they could inhibit the expression of Gal alpha 1,3 Gal synergistically, leading to stronger resistance of xenograft against cytolysis.

3T3 Cells↗
PubMed2003

Expression of human alpha-galactosidase leads to reduction of major xenoepitope Galalpha(1,3) Gal in NIH 3T3 cell.

AIM: To examine the effects of the expression of alpha-galactosidase on the expression of the major xenoepitope Galalpha(1,3) Gal (G antigen) in NIH 3T3 cell. METHODS: The expression levels of G antigen and H antigen and binding of human natural antibodies (IgG and IgM) and complement (C3c) to NIH 3T3 cells were analyzed by flow cytometry. Western blot was employed to further determine the expression of glycoproteins of G antigen. Cytolysis assay with normal human serum was performed by MTT assay. RESULTS: In transfectants, Western blot showed that the binding of human IgG to glycosylated proteins located on the cell membrane was decreased, even abrogated totally. Together with the reduced binding of Gs-IB4 (Griffonia simplicifolia) to transfectants, the stable expression of human alpha-galactosidase effectively inhibited Galalpha(1,3) Gal, Gal epitope synthesis in NIH 3T3 cell. As a result, the xenoreactivities of human IgG, IgM, and C3c were reduced by 73.4 %, 22.3 % and 47.9 %, respectively, while the cell lysis mediated by human XNA and complements was decreased by 42.4 %. CONCLUSION: The stable expression of human alpha-galactosidase in NIH 3T3 cell strongly inhibits the expression of Gal epitopes, resulting in abrupt reduction in xenorejection induced by human serum.

Animals↗
PubMed2002

Total salivary IgA, serum C3c and IgA in obese school children.

Studies of the immunologic function in adult obese humans and experimental models indicate that excess adiposity is associated with impairments in host defense mechanisms. The aim of this work was to analyze the secretory and humoral immune system in obese children (n = 105, 55 boys, 50 girls ), between 6 and 13 years of age. Samples of non-stimulated saliva and whole blood were collected from fasting patients. Total salivary IgA (IgAsal), serum C3 complement (C3c) and Immunoglobulin A (IgA) were determined by quantitative radial immunodifussion on agar gel layers ( Diffu-plate, Biocienti;fica SA ). Results, expressed as mg/dl, were compared to laboratory reference values from healthy children of either sex in the same range of age that belong to the same socioeconomic class (n = 60). Data (Mean +/- 1 SD) of the whole population were: IgAsal: 11.4 +/- 4.8 vs 14.8 +/- 6.9; C3c: 190.7 +/- 53.1 vs 126.3 +/- 45.5; IgA: 194.5 +/- 101.5 vs 157.2 +/- 19.9. Data distribution showed higher frecuencies near the zone of the highest reference values for serum C3c; when results of IgA and IgAsal were expressed as percentage of the mean reference value, 51% and 48.6% of the whole studied population presented data lower than 100% and 75% respectively. These results show a compromised secretory immune system without incidence of clinical symptoms and infections, whereas humoral immunity might not be profoundly affected.

Journal Article↗