PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “complement C3 inhibitor”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

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

At least 757 records · Page 42Linked to original sources
PubMed1992

Paramyosin inhibits complement C1.

We report here the results of studies showing that inhibition of C is a property of several invertebrate paramyosins. Paramyosins from Taenia solium, Schistosoma mansoni, and the mussel Mytilus edulis bind polymeric collagen and can be isolated from crude extracts of tissues by collagen affinity. These paramyosins inhibit C1 function whether the C1 is isolated or present in C2-deficient serum. Because T. solium paramyosin was the best inhibitor, we concentrated further studies on this molecule. T. solium paramyosin binds purified C1q in solution with a dose/response similar to C1r2S2. Further studies of the C1-paramyosin interaction indicate that: 1) C4 is not activated, 2) C4b2a decay is not affected, and 3) there is no effect on the efficiency of C3-9, as provided in EDTA-chelated guinea pig serum, in lysing SRBC. Thus, paramyosin inhibition is directed at the initiation of the classical pathway. The results suggest that paramyosins of helminthic parasites may have a role as modulators of the host immune response through C inhibition at C1.

Animals↗
PubMed2005

Complement inhibitor of C5 activation from the soft tick Ornithodoros moubata.

Blood-feeding ticks must control C activation or be damaged by the host inflammatory response. We report the characterization and expression of a novel, relatively small, broad-acting C inhibitory protein (termed OmCI) from the soft tick Ornithodoros moubata. The native 17-kDa nonglycosylated protein inhibits both human and guinea pig classical and alternative C activation pathways. The IC50 values for each pathway were 12 and 27 nM, respectively, in hemolytic assays using human serum diluted 40-fold. The cDNA encodes a protein of 168 aa, including an 18-aa secretion signal sequence that is absent in the mature form. The inhibitor has 46% amino acid identity with moubatin, a platelet aggregation inhibitor also from O. moubata that is an outlying member of the lipocalin family. Native OmCI had no inhibitory effect on the addition of C8 and C9 to preformed C5b-C7 and C5b-C8 to form the membrane attack complex and no effect on the rate of C3a production by the C3 convertase enzymes C4bC2a, C3(H2O)Bb, or C3bBb. Both recombinant and native OmCI abolish production of C5a by human classical (C4bC3bC2a) and alternative (C3bC3bBb) C5 convertases. Addition of excess C5 but not C3 competes away the inhibitory activity of OmCI, indicating that OmCI targets C5 itself rather than inhibiting the C5 convertase C4bC3bC2a itself. Direct binding of OmCI to C5 was demonstrated by Western blotting and gel filtration chromatography using 125I-labeled proteins. OmCI is the first lipocalin family member shown to inhibit C and also the first natural inhibitor that specifically targets the C5 activation step.

Amino Acid Sequence↗
PubMed2004

The inflammatory response in mild and in severe psoriasis.

BACKGROUND: Psoriasis is a chronic and recurrent inflammatory skin disease. The inflammatory response represents a fundamental ability of the organism to protect itself from infectious agents and from injury. OBJECTIVES: To evaluate the inflammatory response in mild and in severe psoriasis, to evaluate the endogenous systems counterbalancing the deleterious effects of the inflammation products, and to establish values of prognostic significance. METHODS: The study was performed in a control group (n = 40) and in 60 patients with psoriasis vulgaris, half presenting with mild psoriasis, and the other half with severe psoriasis. We evaluated total and differential leucocyte count; elastase, lactoferrin and lipid peroxidation as markers of neutrophil activation; total plasma antioxidant capacity (TAS), transferrin, ceruloplasmin, alpha(1)-antitrypsin and alpha(2)-macroglobulin as markers of the endogenous antioxidant and antiprotease systems; and fibrinogen, erythrocyte sedimentation rate, C-reactive protein (CRP), haptoglobin, C3 and C4 complement proteins as markers of inflammation. RESULTS: Our data suggested that psoriasis is an inflammatory condition in which neutrophils seem to play a crucial role by contributing to the development of oxidative and proteolytic stress. The worsening of the disease seemed to be linked to the enhancement of the inflammatory response and of the imbalance between neutrophil activation products and their inhibitors. CONCLUSIONS: We propose values for elastase, CRP, elastase/alpha(2)-macroglobulin, elastase/alpha(1)-antitrypsin, thiobarbituric acid/TAS and elastase/neutrophil ratios with prognostic significance for the worsening of psoriasis.

Adult↗
PubMed2002

[Circulating immune complex and complement (C3) in a course of pulmonary tuberculosis].

The aim of the current study was to investigate plasma levels of Erythrocyte-Antibody (EA) and Erythrocyte-Antibody-Complement (EAC) circulating immune complexes (CIC) and C3 component of complement in 150 healthy volunteers and 29 patients with active tuberculosis before the treatment and 27 persons with inactive tuberculosis persons with pulmonary tuberculosis. The study showed the occurrence both of types CIC was higher in all groups of patients in comparison with the control (p < 0.001), while there was no significant differences in the patient's groups. The occurrence of CIC EA and EAC in tested groups was significantly greater than in the control (p < 0.001). The analysis of frequency of positive results obtained by RI EA test was showed an approximate percentage in the groups of patients both before antituberculous therapy and after two months treatment and was not significantly lower in inactive TB. The appearance of CIC EAC after two months treatment were significantly greater than in group with active TB (p < 0.01). In inactive TB, the higher occurrence of CIC were obtained by RI EAC test comparing with RI EA method (p < 0.01). On the contrary, in the patients with active TB the greater percentage was revealed using RI EA test (p < 0.05). In this group the examination of concentration of C3 was found higher mean (p < 0.05), whereas the values in patients with inactive TB were in the normal range. In patients after short therapy the level of C3 were decreased significant, when compared with control and other studied groups. The obtained results suggest that in all groups of patients occurrence inhibitor factor of rosettes EA and EAC; the CIC EA, EAC and C3 variability before and after short therapy can be results from the disease and/or application of medicines; the participation of CIC in the inactive stage of TB maybe suggest partially extinguished mycobacterial process.

Adolescent↗
PubMed1986

Complement activation in cystic fibrosis respiratory fluids: in vivo and in vitro generation of C5a and chemotactic activity.

Experiments performed in vitro have demonstrated that leukocyte neutral proteases produce an important mediator of inflammation, C5a, by proteolysis of the C5 component of the complement system. Cystic fibrosis (CF) lung fluids were characterized by high levels of neutrophils (39% of total cells versus 2% in normals) and contained significantly elevated amounts of elastolytic activity (mean 17.7 ng/micrograms total protein) compared to the lung fluids obtained from normal volunteers (0.2 ng elastolytic activity/micrograms protein, p = 0.001). The objective of these studies was to determine if complement activation and complement-derived chemotactic activity are present in CF lung fluids. C3c peptide representing activation of C3 could not be identified in the bronchial-alveolar lung lavage fluids of normal subjects but was readily identified by means of crossed immunoelectrophoresis in CF lung fluids (n = 9, mean 49% of C3); the mean level of C3 was decreased in CF lung specimens. Chemotactic activity was significantly elevated in lung fluids of the CF patients when compared to normal lung fluids. Using gel-filtration chromatography and a sensitive radioimmunoassay the chemotaxin present in CF specimens was identified as the anaphylatoxin C5a. C5a levels in the bronchial-alveolar lavage fluids of CF patients was inversely related to volume in liters expired in 1 s of a forced expiratory maneuver expressed as a percent of vital capacity determined from a forced expiratory maneuver (r = -0.72). Because there was a direct relationship between the total elastolytic activity present in CF airways and the concentration of C5a (r = 0.97, p = 0.03), it was postulated that airway proteases with elastolytic activity also cleave C5, nonimmunologically producing C5a. Detailed inhibition assays revealed that much of the total elastolytic activity had the inhibition profile of a serine proteinase. The levels of the serine proteinases were closely correlated with the numbers of neutrophilic leukocytes present per ml of lavage fluid (r = 0.7, p = 0.05). However, inhibitors of leukocyte serine proteases did not prevent the generation of additional chemotactic activity and the proteolysis of radiolabeled C5 substrate was not prevented by inhibitors of neutrophil elastase. Although the purified metalloelastase of Pseudomonas aeruginosa was active on cell-bound and free C5 yielding C5a, inhibition of this bacterial protease in CF lung fluids only partially blocked cleavage of the alpha- and beta-chains of C5.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1987

Amino acid sequence of a 32-residue region around the thiol ester site in duck ovostatin.

To obtain the amino acid sequence at the thiol ester site in duck ovostatin for comparisons with other proteins, the native ovostatin was labeled with 14CH3NH2 at the reactive thiol ester site. The modified protein was reduced, carboxymethylated, and digested with trypsin. 14C-labeled peptides isolated by gel filtration with Sephadex G-50, ion-exchange chromatography on DEAE-cellulose and HPLC were subjected to automated sequence analysis, and the stretch of 32 amino acid residues containing the 14CH3NH2-binding site were determined. A comparison of this sequence with the corresponding sequences in alpha 2-macroglobulin, and complement components C3 and C4 revealed 72, 31 and 34% homology, respectively. The results indicate that ovostatin is a close relative to plasma alpha-macroglobulins and may share a common ancestor with C3 and C4.

Amino Acid Sequence↗
PubMed2003

Serum-resistant strains of Borrelia burgdorferi evade complement-mediated killing by expressing a CD59-like complement inhibitory molecule.

Borrelia burgdorferi, the etiological agent of Lyme disease, comprises three genospecies, Borrelia garinii, afzelii, and burgdorferi sensu strictu, that exhibit different pathogenicity and differ in the susceptibility to C-mediated killing. We examined C-sensitive and C-resistant strains of B. burgdorferi for deposition of C3 and late C components by fluorescence microscope and flow cytometry. Despite comparable deposition of C3 on the two strains, the resistant strain exhibited reduced staining for C6 and C7, barely detectable C9, and undetectable poly C9. Based on these findings, we searched for a protein that inhibits assembly of C membrane attack complex and documented an anti-human CD59-reactive molecule on the surface of C-resistant spirochetes by flow cytometry and electron microscopy. A molecule of 80 kDa recognized by polyclonal and monoclonal anti-CD59 Abs was identified in the membrane extract of C-resistant strains by SDS-PAGE and Western blot analysis. The molecule was released from the bacterial wall using deoxycholate and trypsin, suggesting its insertion into the bacterial membrane. The CD59-like molecule acts as C inhibitor on Borrelia because incubation with F(ab')(2) anti-CD59 renders the serum-resistant strain exquisitely susceptible to C-mediated killing and guinea pig erythrocytes bearing C5b-8, unlike the RBC coated with C5b-7, are protected from reactive lysis by the bacterial extract. Western blot analysis revealed preferential binding of the C inhibitory molecule to C9 and weak interaction with C8 beta.

Antibodies, Blocking↗
PubMedDate not supplied

Serine proteases as mediators of radiographic contrast media toxicity.

Iodipamide, iodoxamine, iothalamate, diatrizoate, and ioxitalamate exhibit a dose-dependent prolongation of coagulation time of global and monospecific functional coagulation tests. This is due to an inhibition of fibrin polymerization induced by these contrast media. Furthermore, a dose-dependent generation of fibrinolytic split products by RCM was found. At low doses, biliary RCM cause hypercoagulation by binding to spontaneously existing fibrinolytic products. Biliary RCM cause a dose-dependent decrease of hemolytic complement activity and decrease of complement factors of C3, B, and, to a lesser extent, C4. Nephrotopic RCM do not show these effects. By crossed immunoelectrophoresis B and C3 split products were not detected after in vitro incubation of iodipamide in serum or EDTA-blood. In contrast, zymosan, inulin, and dextran sulfate incubation of sera readily resulted in Bb and C3b generation. The failure to demonstrate complement split products was not due to artifacts. As a working hypothesis unspecific binding of RCM to blood proteins followed by interference with antithrombin and antiplasmin inhibitor functions is proposed. Possibly other antiproteases might be involved too. This results in a lowering of the clinical manifestation threshold of coagulation and fibrinolysis. The mechanism of complement activation remains unclear, since it is not influenced by EDTA, aprotinin, steroids, or by specific sera depleted of prekallikrein, Hageman factor, C2, and gamma-globulins.

Animals↗
PubMed1988

Lewis lung carcinoma cells enhance the synthesis of C3 and are opsonized by C3 secreted from murine macrophages.

We investigated the effect of Lewis Lung carcinoma cells on the production of C3 by murine macrophages and examined the capacity of secreted C3 to opsonize Lewis Lung carcinoma cells. C3 released in culture from macrophages obtained from tumor-bearing C57Bl/6 mice as well as from normal macrophages exposed to Lewis Lung carcinoma cells in vitro was measured by hemolytic assays and by Western blot. We found that contact with tumor cells in vivo as well as in vitro enhanced the amount of C3 secreted by murine macrophages by a factor of 2-3. The inflammatory agent carrageenan caused only a small increase in the amount of secreted C3. On Western blots of concentrated macrophage supernatants, there was partial cleavage of secreted C3 which was, however, not more pronounced in the case of C3 from tumor-stimulated macrophages than from normal macrophages. Supernatants from normal as well as tumor-stimulated macrophages were capable of opsonizing Lewis Lung carcinoma cells as shown by their capacity to bind human erythrocyte in an immune adherence reaction. Pretreatment of the tumor cells with a protease inhibitor, PMSF, inhibited the capacity of the tumor cells to bind C3, suggesting that a tumor cell-associated protease might be involved in the binding of C3 to the tumor cell surface.

Animals↗
PubMed2003

Studies of structure-activity relations of complement inhibitor compstatin.

Compstatin, a 13-mer cyclic peptide, is a novel and promising inhibitor of the activation of the complement system. In our search for a more active analog and better understanding of structure-functions relations, we designed a phage-displayed random peptide library based on previous knowledge of structure activity relations, in which seven amino acids deemed necessary for structure and activity were kept fixed while the remaining six were optimized. Screening of this library against C3 identified four binding clones. Synthetic peptides corresponding to these clones revealed one analog, called acetylated Ile(1)Leu/His(9)Trp/Thr(13)Gly triple replacement analog of compstatin corresponding to clone 640 (Ac-I1L/H9W/T13G), which was more active than compstatin. This newly identified peptide had 4-fold higher activity when compared with the originally isolated form of compstatin and 1.6-fold higher activity when compared with acetylated compstatin (Ac-compstatin). The structures of Ac-I1L/H9W/T13G and Ac-compstatin were studied by nuclear magnetic resonance, compared with the structure of compstatin, and found to be very similar. The binding of Ac-I1L/H9W/T13G and the equally active acetylated analog with His(9)Ala replacement (Ac-H9A) to C3 was evaluated by surface plasmon resonance, which suggested similarity in their binding mechanism but difference when compared with Ac-compstatin. Compensatory effects of flexibility outside the beta-turn and tryptophan ring stacking may be responsible for the measured activity increase in Ac-I1L/H9W/T13G and acetylated analog with His(9)Ala replacement and the variability in binding mechanism compared with Ac-compstatin. These data demonstrate that tryptophan is a key amino acid for activity. Finally, the significance of the N-terminal acetylation was examined and it was found that the hydrophobic cluster at the linked termini of compstatin is essential for binding to C3 and for activity.

Acetylation↗
PubMed1994

Expression of the components and regulatory proteins of the classical pathway of complement in normal and diseased synovium.

We studied the synthesis of the classical pathway complement components in synovial membrane. Ribonucleic acid was extracted from the synovial membranes of patients with rheumatoid arthritis (RA) or osteoarthritis (OA), as well as from normal synovial membrane. Northern blot and dot blot analysis showed that the mRNAs for all classical pathway complement components (C1qA chain, C1qB chain, C1qC chain, C1r, C1s, C4 and C2) and the fluid-phase regulatory components (C1-inhibitor, C4-bp and factor I) were present in all three types of synovial membrane. Thus, all the components of the classical pathway were expressed in normal and diseased synovium. In an attempt to determine which components were synthesised by each cell type, monocytes (mononuclear phagocytes), human umbilical vein endothelial cells (HUVEC), synovial membrane fibroblasts (from normal, OA and RA synovial membrane) and peripheral blood lymphocytes were cultured in vitro and secretion rates of individual components were measured and total cellular RNA was analysed by Northern blotting. Monocytes secreted C1q, C1r, C1s, C4, C2, C1-inhibitor and C4-bp but not factor I. Fibroblasts secreted C1r, C1s, C2, C3, C1-inhibitor and factor I but not C1q, C4 or C4-bp. HUVEC secreted C1s, C2, C1-inhibitor and factor I but not C1q, C1r, C4 or C4-bp. Lymphocytes did not secrete any of these components. In three instances mRNA was detected in the absence of secreted protein: mRNAs for the C1qA and C1qC chains were detected in HUVEC, whereas the mRNA for the C1qB chain was not, and C4 mRNA was detected in both fibroblasts and HUVEC.(ABSTRACT TRUNCATED AT 250 WORDS)

Arthritis, Rheumatoid↗
PubMed1980

Inhibition of immune precipitation by complement.

Immune precipitation of bovine serum albumin (BSA) by rabbit anti-BSA antibody (Ab) was studied at 37 degrees C in the presence of normal human serum, normal rabbit serum, decomplemented serum and reagents permitting complement activation either by the classical pathway or the alternative pathway. Inhibition of precipitation occurred in the presence of complement. Antibody-excess complexes were kept soluble more easily than complexes formed at equivalence. Human serum was a better inhibitor than rabbit serum. Analysis of the phenomenon showed that during the first minutes of the reaction immune complexes were maintained in solution by the classical pathway only, but at later stages the alternative pathway was essential. Such soluble immune complexes precipitated after further incubation for 24 hr. The subsequent addition of ethylenediamine tetra-acetate (EDTA) to serum at 37 degrees C holding immune complexes in solution led to a slow aggregation of the complexes. Their size was found to be approximately 25S as assessed by sucrose density-gradient ultracentrifugation and they bore C3 and C4 fragments.

Animals↗
PubMed1993

Protection of germinal centres from complement attack: decay-accelerating factor (DAF) is a constitutive protein on follicular dendritic cells. A study in reactive and neoplastic follicles.

The development of B-cell memory is linked to the presence of germinal centres. This process is dependent on the presence of antigen, usually in the form of immune complexes with antibody, on the surface of the follicular dendritic cells (FDCs) that form a network in the germinal centre. The presence of immune complexes poses a constant danger of activating complement. Decay accelerating factor (DAF, CD55) and the membrane attack complex (MAC) inhibitor (CD59) are two cell proteins whose sole function is to protect cells from the action of complement, the former affecting the earlier components of the complement cascade, and the latter the terminal ones; both are bound to the cell surface via a glycosylphosphatidylinositol link. DAF but not CD59 could be demonstrated on FDCs. DAF is also present on the FDCs in follicular lymphomas despite the absence of complement (C3) in neoplastic follicles. This indicates that DAF is constitutive to FDCs but does not preclude the possibility that its expression is increased when immune complexes are deposited.

Antigens, CD↗
PubMed2005

Protective effect of aprotinin against lung damage in patients undergoing CABG surgery.

OBJECTIVE: We investigated the protective effects of aprotinin, administered in the pulmonary artery, on lung damage after cardiopulmonary bypass (CPB). METHODS: A total of 20 patients undergoing elective coronary artery bypass grafting operations was included in the study and divided into two groups. In the aprotinin group (study group) (n = 10) the drug was administered in the pulmonary artery (15,000 KIU/min) via the pulmonary artery catheter. The control group (n = 10) received only placebo. Blood gas measurements, respiratory function tests, malondialdehyde (MDA), nitric oxide (NO), C4 and leukocyte counts were determined as parameters. Blood samples were taken before and after cross clamping. Lung biopsies were taken before and after CPB. RESULTS: In the aprotinin group, forced expiratory volume (FEV1) and paCO2 values were better than in the control group. The postclamping MDA value in the study group was 20.6 +/- 8.7 etamol/ml and in the control group 37.5 +/- 9.6 etamol/ ml. The post clamping NO value in the study group was 261.9 micromol/l and in the control group 147.20 +/- 27.6 micromol/l. C4 levels were found to be better in the study group than in the control group: reduced levels of C4 were found to be statistically significant (study group postclamping: 12.98 +/- 2.63 mg/dl vs. control group 20.6 +/- 11.81 mg/dl). The increase in leukocyte count was found to be statistically significant (12.63 +/- 3.83 x 10(3) vs. 7.27 +/- 1.72 x 10(3). The difference between the preoperative and postoperative FEV1 in the control group was statistically significant. A statistically significant difference was found in the postoperative FEV1 in both groups. CONCLUSION: Aprotinin administered in the pulmonary artery during CPB had a protective effect against lung damage after open-heart surgery.

Aprotinin↗
PubMed1994

Purification and characterization of a collagen-degrading protease from Porphyromonas gingivalis.

A trypsin-like protease was purified from spent culture medium of oral pathogen Porphyromonas gingivalis by chromatography on columns of DEAE-Sepharose, gel filtration on Sephadex G-100, and chromatofocusing on PBE-94. Purified enzyme showed a single band on SDS-polyacrylamide gel electrophoresis with an estimated molecular weight of 55,000. Purified protease hydrolyzed type I, III, IV, and V collagen from human placenta, and type I collagen from rat tail and calf skin, but did not hydrolyze type II collagen from chicken sternal cartilage. The purified enzyme also hydrolyzed the C3 component of complement, fibrinogen, fibronectin, alpha 1-antitrypsin, alpha 2-macroglobulin, apotransferrin, and human serum albumin. The hydrolytic activity of the purified enzyme on chromogenic substrates was limited to substrates with arginine in the P-1 position, although synthetic peptides were also cleaved at Lys-X linkage. The enzyme was activated by reducing agents dithiothreitol, L-cysteine, and glutathione and inhibited by cysteine protease inhibitors N-ethylmaleimide, iodoacetic acid, and iodoacetamide. The enzyme was also inhibited by trans-epoxysuccinyl-L-leucylamido(4-guanidino)butane (E-64), leupeptin, antipain, salivary histidine-rich protein (HRP-5), soybean trypsin inhibitor, and EDTA. Since the protease is able to degrade the connective tissue components of periodontal tissue as well as components of host defense mechanism, this enzyme may be a potent virulence factor of P. gingivalis involved in invasion and tissue destruction.

Amino Acid Sequence↗
PubMed1992

Glomerular hemodynamics and eicosanoid synthesis in a rat model of IgA nephropathy.

We sought to study glomerular pathophysiology in a model of IgA nephropathy (IgAN). Preliminary experiments with oral immunization indicated that Lewis rats had higher IgA levels and IgA/IgG ratios than Wistar, Fischer or Sprague-Dawley rats. Six groups of Lewis rats were studied: four continuously orally immunized for eight weeks with bovine gamma globulin (BGG) in the drinking water, the other two non-immunized controls. Groups of immunized rats were treated with a thromboxane receptor antagonist (SQ 29,485) and/or a thromboxane synthase inhibitor (UK 38,485). After systemic challenge, microscopic hematuria was present in 84% of immunized rats not given anti-thromboxane drugs versus 18% of non-immunized rats (P less than 0.01). Immunized rats showed predominantly IgA glomerular deposits with lesser IgG and C3, and produced more glomerular thromboxane than controls, but no significant increase in prostaglandin E2. Immunized rats also had reduced GFR and RPF, but not a reduced filtration fraction, compared to controls. Thromboxane synthase inhibitor diminished glomerular thromboxane and increased prostaglandin E2 in immunized rats. Anti-thromboxane therapy reduced hematuria and apparently re-established the RPF but not the GFR in immunized rats, yielding a reduced filtration fraction. We propose that increased thromboxane, in concert with mesangial contraction that is unaffected by anti-thromboxane drugs, contributes to the pathophysiology in this model of IgAN.

Animals↗
PubMed2002

Membranous glomerulonephritis, antiphospholipid syndrome, and persistent low C3 levels associated with meningococcal disease.

A young male patient with a recent history of meningococcemia was referred to our hospital in his recovery period. He had signs suggesting deep venous thrombosis in the legs but no other abnormalities on physical examination at admission. Laboratory results showed proteinuria (3.1 g/day), prolonged activated partial thromboplastin time (56.3 s), low level of C3c (0.19 g/l), high titers of both IgM (27.04 MPLU/ml) and IgG (74.88 GPLU/ml) anticardiolipin antibodies and recanalized thrombotic changes in the deep veins of the lower extremities on venography. Histopathological diagnosis of the kidney disease was membranous glomerulonephritis. He was started on an angiotensin-converting enzyme inhibitor to reduce proteinuria and an oral anticoagulant to prevent thromboembolic events. Since no reduction in proteinuria was observed at the 10th month of therapy, the angiotensin-converting enzyme inhibitor was discontinued. On his last follow-up, approximately 1.5 years after meningococcemia, he had no complaints and no abnormal findings on physical examination. While both IgM and IgG anticardiolipin antibody titers returned to the normal range, he still had persistent proteinuria and hypocomplementemia.

Adult↗