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PubMed1993

Levels of complement regulatory molecules in lung cancer: disappearance of the D17 epitope of CD55 in small-cell carcinoma.

The levels of complement-regulatory molecules (complement receptor type one [CR1], decay-accelerating factor [DAF], membrane cofactor protein [MCP], and an inhibitor of membrane attack complex [CD59]) in lung cancer cells were analyzed to investigate the relation between their expression and histological subtypes, and the possibility of homologous complement deposition on cancer cells. In 25 cell lines (10 adenocarcinoma, 3 large-cell carcinoma, 7 small-cell lung cancer [SCLC], and 5 squamous cell carcinoma), flow cytometric analysis revealed that MCP was expressed in all cell lines, whereas none of the cell lines was CR1-positive. CD59 was detected in all cells. The DAF epitope defined by IA10 was expressed in all cells except one large cell carcinoma cell line. However, another epitope for anti-DAF monoclonal antibody, D17, was not detected in 5 (71.4%) SCLC and in 4 (22.2%) non-small-cell lung cancer. This disparity was seen in most cell lines, irrespective of histological subtypes. The loss of D17 reactivity seemed to be pertinent to malignant phenotype, because most of the normal pulmonary cells possessed the D17 epitope. Furthermore, a cell line lacking DAF (IA10-/D17-) allowed alternative pathway-mediated homologous complement (C3) deposition after pretreatment with anti-MCP antibody. This raises a new possibility for immunotargeting of cancer. These cell lines should be useful in studying the biology of lung cancer.

Antigens, CD↗

PubMed1996

[Changes in the production of reactive oxygen species from neutrophils following a 100-km marathon].

Recently, the numbers of city marathon runners and joggers have increased. They believe that exercise can enhance their fitness level and health maintenance. However, many researchers have suggested that exhausting exercise may increase the risk of infection and free radical generation. In this study, eight male and ten female city marathon runners who participated in the Akita Nairiku Resort Cup 100-km Challenge Marathon Race were studied using luminol-dependent chemiluminescence (LDCL) to examine the ability of their neutrophils to produce reactive oxygen species. Furthermore, serum opsonic activity using LDCL, serum concentrations of the third and fourth components of the complement (C3, C4), the total number of leukocytes, and proportion of leukocytes were also determined. Evaluation of LDCL was undertaken using the maximum light emission (peak height) and the time to reach the maximum light emission (peak time) in the response curve of LDCL. Following the race, the peak time was prolonged by 11% in males and 15% in females, and the peak height increased by 68% in males and 48% in females. These results suggest that exhausting exercise stimulates neutrophils to produce reactive oxygen species. The total number of leukocytes increased about twofold, whereas the number of neutrophils increased about threefold after the race as compared to before. The rate of the increase in leukocytes was closely associated with that of neutrophils (r = 0.96, P < 0.01). Therefore, the leukocytosis observed in this study was dependent on neutrophilia. Serum opsonic activity and serum concentrations of C3 and C4 were not changed following the race. The increase in the ability of neutrophils to produce reactive oxygen species and neutrophilia after the race, suggests that a large quantity of reactive oxygen species may be produced in vivo following exhausting exercise.

Adult↗

PubMed1986

Immunoblotting analysis of plasma protein processing in the secretory pathway of rat liver: identification of proteolytic conversion sites of complement pro-C3 and prohaptoglobin.

Using an immunoblotting technique, we have studied the processing of plasma proteins in subcellular fractions of rat liver including rough and smooth microsomes and the Golgi subfractions. Each subcellular fraction was directly subjected to SDS-polyacrylamide gel electrophoresis and analyzed by immunoblotting with antibodies against alpha 1-protease inhibitor, haptoglobin, and the third component of complement (C3) in combination with 125I-protein A or 125I-rabbit anti-(goat IgG)-IgG. The results demonstrated that proteolytic processing of precursors of complement C3 and haptoglobin occurs in different compartments along the secretory pathway; conversion of prohaptoglobin takes place in the endoplasmic reticulum, while that of pro-C3 occurs in the Golgi complex. The processing in oligosaccharide chains of glycoproteins was also analyzed. The Golgi fraction was characterized by the presence of the mature 56 kDa alpha 1-protease inhibitor, which was indistinguishable from the serum alpha 1-protease inhibitor in SDS-polyacrylamide gel electrophoresis. In contrast, the immature 51 kDa form was the only form of alpha 1-protease inhibitor found in the microsomal fraction. Similar results were obtained for the beta subunit of haptoglobin; the immature 33 kDa form was detected in the microsomal fraction, while the mature 36 kDa form was found in the Golgi fraction. Taken together, these results identified the intracellular sites where these plasma proteins are modified by selective proteolysis and/or glycosylation.

Animals↗

PubMed1987

[IgG, IgM, IgA, secretory IgA and the complement components C3, C4 and C9 in the large intestine in nonspecific ulcerative colitis and Crohn disease].

The immunohistological study of the large intestines excised from 20 patients with ulcerous colitis and Crohn's disease was made with the use of the indirect immunofluorescence test. A considerable increase in the number of IgG immunocytes has been noted in the lamina propria of the mucous membrane, especially in infiltrations around ulcers. In cases of a highly active inflammatory process accompanied by the pronounced destruction of the epithelium, IgG and C3, C4, C9 were detected in the epithelium of crypts and in blood vessels of the mucous membrane and the submucosa. One-third of the patients showed a decrease in the number of crypts with secretory and serum IgA. The authors suggest that immune complexes take part in maintaining the chronic inflammatory process.

Colitis, Ulcerative↗

PubMed1982

Inhibition of in vitro natural killer activity by the third component of complement: role for the C3a fragment.

Purified human native third component of complement, C3, was found to inhibit in vitro natural killer (NK) cell cytotoxicity in both mouse and human systems. The effect was dose and time dependent, a 50% inhibition being reached with 190 nM C3 (35 micrograms/ml) added during the NK assay or after a 30-min preincubation of the effector cells with this C3 concentration. C3 was shown to act at the effector-cell population level because pretreatment of the target cells did not modify the NK lysis. The inhibition was not due to general cytotoxicity nor to cell agglutination. Moreover, another in vitro cytotoxicity system (represented by alloreactive cytotoxic lymphocytes) was not affected by purified C3. Structural analysis of the active part of the C3 molecule shows that the C3-induced inhibition is supported by the C3a fragment. Release of carboxyl-terminal arginine residue by carboxypeptidase B, converting C3a into des-Arg77-C3a, did not alter the inhibitory effect displayed by this fragment. These results suggest that C3a may play an important role in the regulation of NK activity.

Animals↗

PubMed1983

Immunological findings in kala-azar, Iran.

Quantitation of immunoglobulins in patients with systemic leishmaniasis show a rise in IgM and IgG. Complement C3 levels in severely ill patients were very low, whereas generally within normal range in patients with uncomplicated recoveries. The cell mediated immune response of those kala-azar patients examined appeared to be depressed as measured by PHA skin tests. This depression was rapidly reversed following chemotherapy with Glucantim.

Adolescent↗

PubMed1997

Structural C3 diversity in fish: characterization of five forms of C3 in the diploid fish Sparus aurata.

In virtually all species examined to date, the functionally active third component of complement (C3) is encoded by a single gene. We have recently demonstrated, however, that trout possess three structurally and functionally distinct active C3 that represent the products of at least two different C3 genes. In the present study, we provide evidence that multiple forms of functional C3 occur not only in the rainbow trout (Salmo gairdneri), a quasi-tetraploid old teleost fish, but also in the diploid gilthead sea bream (Sparus aurata), a modern teleost fish. In the gilthead sea bream, we have characterized five different forms of C3 (C3-1, C3-2, C3-3, C3-4, and C3-5); in addition, we have identified and isolated a C5-like molecule. Each of the six proteins was composed of an alpha-chain and a beta-chain; however, only the C3 isoforms contained a thioester bond in their alpha-chains. These proteins all differed in the molecular masses of their alpha- and beta-chains and in their glycosylation patterns, reactivity with various Abs, tryptic peptide maps, and NH2-terminal sequences of their chains. These observations together with the fact that each of the six proteins were also purified from a single fish suggest that the C3 isoforms represent the products of several genes. The presence of multiple forms of C3 in a modern diploid fish, very distant in evolutionary time from the trout, strongly suggests that the C3 isoforms generated once from a single C3 gene have remained functional in the genomes of these animals. These findings not only have important consequences for our understanding of the evolution of the C3 protein, but also provide evidence for the formation and generation of a new C3-related gene family.

Amino Acid Sequence↗

PubMed1996

The effect of eye closure on protein and complement deposition on Group IV hydrogel contact lenses: relationship to tear flow dynamics.

PURPOSE: This study was designed to determine the effect of overnight eye closure on the rate and composition of protein deposition on high water content ionic matrix soft contact lenses (Group IV SCLs) and to extrapolate from this data information on the probable change in the rate of reflex-type tear secretion associated with eye closure. METHODS: Group IV SCLs were temporally sampled after equivalent periods of wear under closed eye (C) or open eye (O) conditions. Lenses were rinsed in saline and the majority of the tightly bound protein extracted at 90 degrees C in 40% urea, containing 1% SDS, 1 mM DTT, 100 mM Tris-HCl (pH 8.00). Residual protein was determined by Coomassie staining of the extracted lenses and densitometric analysis. Extracted protein was quantitated and separated by SDS-PAGE. Gels were either stained with Coomassie blue or reversibly stained with imidazole-zinc and blotted. Blots were PAS stained, or lectin and antibody probed for glycoproteins, secretory IgA (sIgA), IgG, lysozyme and complement C3. Laboratory simulated deposition studies were carried out on unworn lenses exposed to HPLC purified lysozyme. RESULTS: The protein in the saline rinse, to a large degree mirrored the composition of tear fluid in which the lens had been residing (O or C). This would suggest that the saline wash consists of residual tear fluid and loosely adherent protein. In contrast, the urea extracts were highly homogeneous consisting primarily of lysozyme and to lesser extent lysozyme dimer. This supports the contention that the Group IV SCL functions in the eye much as cationic exchange resin selectively absorbing lysozyme. C extracts also proved relatively enriched in trace amounts of sIgA, IgG and complement C3 and its breakdown products. High levels of C3 and C3 breakdown products were specifically recovered only in the C worn lens extracts from a subject experiencing unilateral contact lens associated corneal infiltrates from the affected eye. In all subjects, markedly less protein (lysozyme) was recovered in urea extracts of lenses exposed to 7-8 h of closed eye as compared to open eye wear (0.20 +/- .08 versus 0.79 +/- .15 mg/lens (n = 6)). Temporal studies further revealed that deposition was linearly related to duration of wear during the initial phase of conditioning film formation giving rise to rate constants for lysozyme deposition of 2.2 +/- 0.29 (n = 5) and 0.20 +/- 0.06 microgram/min (n = 4) under open and closed eye conditions respectively. With further wear, deposition eventually reached a steady state. Under laboratory conditions, lysozyme was much rapidly and quantitatively removed from solution in a manner following a hyperbolic plot. This suggests that during the initial phase of deposition the rate of deposition is limited by the capacity of the tear fluid to deliver lysozyme to the lens surface under these two extremes of conditions. CONCLUSIONS: Eye closure profoundly affects the rate of lysozyme deposition on Group IV hydrogels and the composition of minor biofilm constituents in a manner that could affect biocompatibility. Findings support the contention that eye closure results in a > 90% reduction in the rate of reflex-type tear secretion.

Adult↗

PubMed1998

Tear changes in contact lens wearers following overnight eye closure.

PURPOSE: Tear protein composition alters during eye closure, by becoming rich in secretory IgA (sIgA) and certain complement proteins. This may reflect altered ocular defense mechanisms during eye closure. Since overnight wear of contact lenses (CLs) is associated with an increased risk of corneal infection and inflammation, this study aimed to quantify tear protein changes with overnight soft CL wear. METHODS: Non-stimulated tears were collected from 9 CL wearers prior to CL wear (baseline), after daily CL wear, and after 8 h sleep. Lenses were removed following wear and were extracted in 80% urea at 95 degrees C. Secretory IgA, complement C3 and C4, were measured using ELISA and total protein using the Pierce BCA assay. Assays were performed on tear samples and CL extracts. RESULTS: Baseline tear protein concentrations were: 0 total tear protein (9.37 +/- 2.97 mg/mL), C3 (4.4 +/- 2.1 micrograms/mL), C4 (0.1 +/- 0.1 micrograms/mL), and sIgA (0.84 +/- 0.34 mg/mL). There were no differences in any protein levels between daily CL wear and no CL wear (p > 0.05). Following sleep, protein concentrations were: total tear protein (43.64 +/- 24.30 mg/mL), C3 (72.5 +/- 49.9 micrograms/mL), C4 (6.7 +/- 5.2 micrograms/mL), and sIgA (5.53 +/- 5.15 mg/mL). Total protein extracted from CLs after daily wear was 90 +/- 27 micrograms/CL and, after overnight wear, 152 +/- 24 micrograms/CL. Negligible levels of C3, C4 and sIgA were recovered from CL extracts. CONCLUSIONS: Uncomplicated daily use of soft CLs does not appear to alter certain tear proteins compared with baseline levels. Uptake of these proteins by the CL does not appear to deplete the tear protein levels. Overnight levels of all tear proteins were increased, compared to daily CL wear.

Adult↗

PubMed1988

The immunological aspects of keloid tumor formation.

This study considered possible immunological alterations that may be associated with keloid tumor formation. Laser immunonephelometry was used to quantitate circulating immune complexes and complement C3 and C4 among keloid formers. IgG complex level was significantly higher, while C3 and C4 were lower, than in the control population. The raised IgG was positively correlated with C4 (r = 0.15). When considered with reports of earlier workers, keloid genesis could result from genetic predisposition, environmental trigger, or localized and systemic immune complex formations. The relationship of these factors to a disequilibrium between fibroblast synthesis of collagen and turnover degradation still remains unclear.

Adult↗

PubMed2006

[Relations beetwen severity of anemia and certain antiphospholipid antibodies presence in systemic lupus erythematosus patients].

UNLABELLED: Anaemia is a common hematological abnormality in systemic lupus erythematosus (SLE). Autoimmune hemolytic anaemia (AHA) is one of the types of anaemia in SLE. Other reasons of anaemia in SLE are: chronic inflammatory diseases, insufficient level of elements necessary for erythropoiesis and chronic renal disease. The aim of the study was to examine the relations between severity of anemia and presence of certain antiphospholipid antibodies (aPL) in SLE. The study group consisted of 24 patients (one man and 23 women) with active lupus. Anticardiolipin antibodies (aCL), anti-02 glycoprotein I antibodies (anti-beta2 GPI IgM and IgG) and red cell parameters: haemoglobin level (Hb), erythrocytes (RBC), mean corpuscular volume (MCV), mean corpuscular haemoglobin mass (MCH), mean corpuscular haemoglobin concentration (MCHC) and ferritin level were measured before beginning or intensification of treatment. The activity of SLE was measured by SLEDAI and C3 complements. The patients were divided into two subgroups: subgroup with aCL-IgG above 20 u/ml and below 20 u/ml. In patients with aCL-IgG above 20 u/ml the mean Hb level was lower, and the mean ferritin level was significantly higher than in patients with aCL-IgG level below 20 u/ml. We observed a negative, significant correlations between Hb and aCL-IgG (p = 0.01; R = -0.47) and between Hb and anti-32 GPI IgG (p = 0,0003; R = -0,67) and a negative correlation between Hb and activity of SLE estimated by SLEDAI (p = 0.02; R = -0.45) and positive between Hb and C3 complement (p = 0.02; R = +0.5). IN CONCLUSION: antiphospholipid antibodies presence in patients with SLE can influence the severity of anaemia.

Adult↗

PubMed2003

Acylation-stimulating protein precursor proteins in adipose tissue in human obesity.

Recent reports have suggested a link between acylation-stimulating protein (ASP) and complement C3 with obesity, insulin resistance, coronary artery disease, and hyperlipidemia. Our aim was to examine the mRNA expression of C3 and other factors related to ASP production (such as factor B and adipsin) in adipose tissue. The influence of gender and obesity was examined in subcutaneous (SC) and omental (OM) tissues from 16 males and 16 females with body mass index (BMI) from 20 to 54 kg/m(2). The results demonstrate that factor B mRNA expression is higher in males than females in both SC and OM tissues. In female SC tissue, C3 and adipsin mRNA decrease with increasing BMI (r = 0.557, P =.025 and r = 0.717 P =.002, respectively), with no change in factor B. By contrast, in males there was a pronounced increase in C3, adipsin, and factor B in OM tissue with increasing BMI (r = 0.759 P =.001, r = 0.650 P =.006, and r = 0.568 P =.022, respectively). Of note, however, in both men and women there was a marked increase in the OM/SC ratio of C3 and adipsin with increasing BMI. These results suggest that in female SC adipose tissue, there is downregulation of factors related to ASP production in obesity, perhaps to limit further expansion of adipose tissue. In males, there is increased expression in OM tissue. In addition, relative OM/SC expression increases with obesity and these changes may contribute to the development of visceral adipose tissue.

Adipose Tissue↗

PubMed2005

Molecular analysis of a novel hereditary C3 deficiency with systemic lupus erythematosus.

A case of inherited homozygous complement C3 deficiency (C3D) in a patient with systemic lupus erythematosus (SLE) and the molecular basis for this deficiency are reported. A 22-year-old Japanese male was diagnosed as having SLE and his medical history revealed recurrent tonsillitis and pneumonia. He was diagnosed as having C3D because of undetectable serum C3 level. His parents were consanguineous. Sequence analysis of C3D cDNA revealed a homozygous deletion of exon 39 (84bp). A single base substitution (AG to GG) in the 3'-splice acceptor site of intron 38 was identified by sequencing the genomic DNA. Expression of C3Delta(ex39) cDNA, the C3cDNA lacking exon 39, in COS-7 cells revealed that C3Delta(ex39) was retained in endoplasmic reticulum-Golgi intermediate compartment because of defective secretion. These data indicate that a novel AG-->GG 3'-splice acceptor site mutation in intron 38 caused aberrant splicing of exon 39, resulting in defective secretion of C3.

Adult↗

PubMed1986

C3 and Bf complement types in chronic renal failure.

C3 and BF allele frequencies were studied in 55 patients with idiopathic membranous nephropathy (IMN) and unrelated normal individuals from North-East England. Eighteen of these IMN patients progressed to renal failure and C3*S allele showed a significant increase in these patients. A possible mechanism for this increase is briefly discussed.

Alleles↗

PubMed1980

The distribution of lipopolysaccharide in normocomplementemic and C3-depleted rabbits and rhesus monkeys.

To examine the role of complement (C3) in determining the fate of lipopolysaccharide (LPS) in vivo, the distribution of LPS was studied in normocomplementemic (NC) and C3-depleted animals (pretreated with cobra venom factor [CoF]) after intravenous injection of highly purified, radioiodinated Salmonella minnesota R595 LPS. After injection of a lethal (250 micrograms) or nonlethal (5 micrograms) dose of LPS in NC and CoF rabbits and a lethal (5 mg/kg) dose of LPS in rhesus monkeys, the LPS disappeared from blood in a biphasic manner. In all cases, a substantial portion of the dose was removed from blood in an initial disappearance phase (t1/2 < 15 minutes), which, in some cases, was accelerated in CoF-treated animals. LPS remaining in blood beyond 30 minutes persisted with a much increased half-life (> 5 hours). Liver contained the major portion (40%) of tissue-bound LPS (determined by use of 131I-BSA blood marker) in animals killed 3--5 hours after injection. The distribution of LPS in rabbits was found to be dose-indpendent and only minimally changed by prior depletion of C3. In addition, the tissue distribution and cellular localization of LPS in monkeys was similar to that we have reported previously for R595 LPS in NC rabbits and was not substantially changed by prior CoF treatment. These results indicate that binding of C3 to intravenously injected LPS is not required for the initial rapid disappearance from blood. Further, the uptake of LPS by cellular targets, notably the hepatic macrophages (Kupffer cells), is not altered by in vivo decomplementation.

Animals↗

PubMed1997

Clinical evaluation of the centrifugal pump in open heart surgery: a comparative study of different pumps.

The centrifugal pump is now widely used in open heart surgery for its clinical benefits related to the blood elements and the coagulation system. The purpose of this study was to compare the clinical performances of and the outcomes offered by 4 types of centrifugal pumps. For each pump, we investigated the effects on the blood elements, coagulation system, complements, and immunoglobulins during open heart surgery. Four types of centrifugal pumps were used: the HPM-15 (Nikkiso Co.), the Capiox (Terumo Co.), the Lifestream (St. Jude Medical Co.), and the BP-80 (Medtronic, BioMedicus Co.). The platelet count, lactate dehydrogenase (LDH), antithrombin III (AT III), thrombin-antithrombin complex (TAT), complements (C3, C4, and CH50), and immunoglobulins (IgG, IgA, and IgM) were measured before and after cardiopulmonary bypass (CPB). The platelet count was decreased more significantly by the HPM-15 than by any of the other pumps. The other parameters showed no difference among the 4 pumps. In clinical use, each of the 4 types of centrifugal pumps was safe.

Aged↗

PubMed1994

[Analysis of cardiac function of discordant heart xenografts using a blood-perfused, isolated, supported heart model].

UNLABELLED: Changes in cardiac function during hyperacute rejection are not fully understood because of lack of appropriate models. In this study, a blood-perfused, isolated, supported heart model was employed for the analysis of cardiac function in discordant heart xenografts. METHODS: Experiment 1: Changes in left ventricular end-systolic pressure (LVESP) and coronary perfusion pressure (CPP) were measured for 120 min. Dry heart weight after perfusion was measured in the following 4 groups: group A; isolated rat heart perfused with blood from support rat, group B; guinea pig heart, support guinea pig, group C; guinea pig heart, support rat, and group D; guinea pig heart, support rat with cobra venom factor (CVF) pretreatment. Complement C3 of support rat serum in group C and group D was measured by single radial immunodiffusion (SRID). Experiment 2: Fifteen guinea pig hearts perfused with blood from untreated support rats were analyzed for correlation between survival time and LVESP, and CPP as well. RESULTS: In groups A and B, LVESP and CPP was stable up to 120 min. In group C, 4 out of 6 hearts were stopped beating within 120 min. The difference between LVESP at 10 min in group C and that in group B was not obtained, possibly due to high variation of values in group C, whereas CPP in group C was higher than that in group B (p < 0.05). In group D, CVF was shown to deplete complement C3. Group D showed constant LVESP and CPP, similar to non-xenograft groups. Dry heart weight of group C was larger than those of group B and D. There were positive correlations between survival time and LVESP at 10 min, and increasing rate of LVESP after 10 min as well. A negative correlation between survival time and CPP at 10 min was observed, while no correlation was obtained between survival time and increasing rate of CPP after 10 min. CONCLUSIONS: 1) Decreases in LVESP and increases in CPP in xenograft group are considered to be due to hyperacute rejection. 2) These changes can be abolished by depletion of C3. 3) Guinea pig hearts can work well in xenograft condition as in allograft condition in certain circumstances, i.e. depletion of C3. 4) The blood-perfused, isolated, supported heart model is useful for the analysis of cardiac function in discordant xenografts.

Animals↗

PubMed1996

Clinical use of centrifugal pumps and the roller pump in open heart surgery: a comparative evaluation.

Centrifugal pumps have been used widely as the main pump in open heart surgery to reduce damage to blood elements and to reduce the activation of the coagulation system. The purpose of this study was the evaluation and comparison of the effects of two types of centrifugal pumps and of one type of roller pump on blood elements, the coagulation system, complements, and immunoglobulins. Two types of centrifugal pumps (Lifestream; St. Jude Medical, Chelmsford, Massachusetts; and BP-80: Medtronic, BioMedicus, Inc., Eden Prairie, Minnesota, U.S.A.) and one roller pump (Mera Co.) were used separately as the main pump for cardiopulmonary bypass (CPB) in 29 patients. Platelet counts, lactate dehydrogenase, antithrombin III, thrombin-antithrombin complex (TAT), complements (C3, C4, and CH50) and immunoglobulins G, A, and M values were measured before and after CPB and compared. Values, except those for TAT, showed no significant difference among the three groups. The TAT values increased less in each of the centrifugal pump groups than in the roller pump group. This finding suggests that thrombin synthesis might be suppressed by the use of a centrifugal pump.

Adult↗