fibrin and Albuminuria

Experimental autoimmune glomerulonephritis (EAG) was induced in Wistar-Kyoto (WKY) rats by immunization with rat glomerular basement membrane (GBM) in adjuvant. This model is characterized by anti-GBM antibody production, accompanied by focal necrotizing glomerulonephritis with crescent formation. There is also glomerular infiltration by T cells and macrophages. Our hypothesis was that blocking the interaction between CD154 (CD40L) on Th cells and CD40 on antigen-presenting cells should inhibit T-cell activation, and thus the development of EAG.. The in vivo effects of a hamster anti-rat monoclonal antibody to CD154 (AH.F5) were examined in EAG starting at day -1 prior to immunization, day +7 after immunization, or day +14 after immunization.. When administered from day -1 at a dose of 10 mg/kg intraperitoneally three times per week for the duration of the study (4 weeks), AH.F5 resulted in a marked reduction in circulating anti-alpha3(IV)NC1 antibodies, deposits of IgG on the GBM, albuminuria, deposits of fibrin in the glomeruli, severity of glomerular abnormalities, and numbers of glomerular T cells and macrophages. When administered from day +7 at the same dose, AH.F5 resulted in a moderate reduction in the severity of disease, while administration from day +14 had no significant effect.. These studies demonstrate for the first time that early blockade of the CD154-CD40 T-cell costimulatory pathway can prevent the development of crescentic nephritis, and that delayed treatment can reduce the severity of disease. This confirms the importance of T cell mediated immunity in the pathogenesis of EAG, and suggests that strategies targeting T-cell costimulation may provide a novel approach in the treatment of human glomerulonephritis.

Topics: Albuminuria; Animals; Anti-Glomerular Basement Membrane Disease; Antibodies; Antibodies, Monoclonal; Autoantibodies; CD40 Antigens; CD40 Ligand; Creatinine; Fibrin; Fluorescent Antibody Technique, Direct; Immunoglobulin G; Kidney Glomerulus; Male; Rats; Rats, Inbred WKY; T-Lymphocytes

Experimental autoimmune glomerulonephritis (EAG), which is an animal model of Goodpasture's disease, can be induced in Wistar Kyoto rats by a single injection of rat glomerular basement membrane (GBM) in adjuvant. EAG is characterized by circulating and deposited anti-GBM antibodies, focal necrotizing glomerulonephritis with crescent formation, and glomerular infiltration by T cells and macrophages. Our hypothesis was that T cell-mediated immunity, in addition to humoral immunity, was necessary for the development of crescentic nephritis in this model. To investigate the role of CD8+ T cells in the pathogenesis of EAG, the in vivo effects of an anti-CD8 monoclonal antibody (OX8) were examined, with administration starting at the time of immunization (prevention) or 2 wk after immunization, when glomerular abnormalities were first detected (treatment). When administered intraperitoneally at 5 mg/kg, three times per week, from week 0 to week 4 (prevention), OX8 completely inhibited the development of albuminuria, deposits of fibrin in the glomeruli, glomerular and interstitial abnormalities, the influx of CD8+ T cells and macrophages, and glomerular expression of granzyme B and inducible nitric oxide synthase. Circulating anti-GBM antibody levels were not reduced, but there was a reduction in the intensity of antibody deposition on the GBM. When administered at the same dose from week 2 to week 4 (treatment), OX8 greatly reduced the severity of EAG; in particular, the formation of crescents was prevented. These studies demonstrate that anti-CD8 monoclonal antibody therapy is effective in both the prevention and treatment of EAG. They confirm the importance of T cell-mediated immunity in the pathogenesis of this model of Goodpasture's disease. Similar therapeutic approaches may be worth investigating in human crescentic glomerulonephritis.

Topics: Albuminuria; Animals; Anti-Glomerular Basement Membrane Disease; Antibodies; Antibodies, Monoclonal; CD4 Lymphocyte Count; CD8 Antigens; CD8-Positive T-Lymphocytes; Creatinine; Fibrin; Flow Cytometry; Fluorescent Antibody Technique; Immunoglobulin G; Immunohistochemistry; Lymphocyte Count; Male; Rats; Rats, Inbred WKY

A particular Lewis rat substrain (LEW/Maa) develops chronic glomerulonephritis in the anti-Thy 1 model (aThy 1-GN) characterized by increased microaneurysm formation, chronic glomerular sclerosis and persistent albuminuria. This phenotype is accompanied by increased and prolonged glomerular induction of inducible nitric oxide synthase (iNOS) when compared to the LEW/Moe substrain, in which aThy 1-GN resolves quickly. We investigated the effect of selective iNOS inhibition by l-N6-(1-iminoethyl)-lysine (L-NIL) administration on aThy 1-GN in LEW/Maa rats.. Nephritic rats were studied over a period of 7 days. L-NIL-treated animals received 20 mg/day L-NIL in the drinking water starting two days prior to disease induction. iNOS activity was determined in cultured glomeruli and in urine samples, respectively. Severity of aThy 1-GN was determined by scoring glomerular matrix expansion and microaneurysm formation, and by albuminuria measurements (ELISA). Immunohistochemical evaluation was performed including staining for macrophages (ED-1), platelets (PL-1) and fibrin deposition.. L-NIL treated rats (+NIL) showed a significant decrease in peak nitrate production by ex vivo cultured glomeruli, and in urinary nitrate excretion versus untreated nephritic rats (-NIL). Mean arterial pressure remained unchanged in both +NIL and -NIL rats. +NIL rats developed significantly increased albuminuria (+44%) associated with a significant increase in glomerular platelet (+45%) and fibrin deposition (+48%).. Selective inhibition of iNOS aggravated albuminuria in chronic aThy 1-GN in LEW/Maa rats. Induction of iNOS during the inflammatory phase of this model may be a partially protective mechanism by interfering with intraglomerular coagulation processes.

Topics: Albuminuria; Animals; Blood Platelets; Blood Pressure; Chronic Disease; Enzyme Inhibitors; Fibrin; Isoantibodies; Kidney Glomerulus; Lysine; Nephritis; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Rats; Rats, Inbred Lew; Thrombosis

The autoantigen in Goodpasture's disease is known to be the non-collagenous domain of the alpha3 chain of type IV collagen, alpha 3(IV)NC1. There is mounting evidence that alpha 3(IV)NC1 is also a target of autoimmunity in experimental autoimmune glomerulonephritis (EAG). Sado et al. [Kidney Int 1998; 53, 664-671] have reported that recombinant human alpha 3(IV)NC1 and alpha4(IV)NC1 are nephritogenic in WKY rats. We have proposed that immunization with homologous antigen is more appropriate for detailed investigation of autoimmunity in EAG.. To this end, we have cloned and sequenced rat alpha 3(IV)NC1 and expressed it in COS-7 cells. Recombinant rat alpha 3(IV)NC1, secreted into the COS-7 cell supernatant, was purified on an anti-M2 FLAG affinity column and characterized by western blotting. Recombinant antigen was then used to immunize WKY rats, in order to induce EAG.. The recombinant material was antigenic as judged by binding to sera from patients with Goodpasture's disease and a mAb to alpha 3(IV)NC1. Immunization of WKY rats (n=5), with recombinant rat alpha 3(IV)NC1 in FCA at a dose of 1 mg/kg resulted in circulating anti-GBM antibodies directed towards alpha 3(IV)NC1, linear deposits of IgG on the GBM, albuminuria, deposits of fibrin in the glomeruli, severe focal necrotizing glomerulonephritis with crescent formation, and glomerular influx of CD8+ T cells and macrophages. Western blot analysis demonstrated that sera from these rats bound strongly to recombinant rat alpha 3(IV)NC1, as well as to collagenase-solubilized human and rat GBM. The pattern of binding was indistinguishable from that of sera from patients with Goodpasture's disease.. This purified recombinant rat alpha 3(IV)NC1, which is both antigenic and nephritogenic, will be of value in analysing autoimmune responses in experimental anti-GBM disease.

Topics: Albuminuria; Amino Acid Sequence; Animals; Antibodies; Autoantigens; Autoimmune Diseases; Base Sequence; Collagen; Collagen Type IV; Creatinine; Fibrin; Glomerulonephritis; Immunoglobulin G; Kidney; Male; Molecular Sequence Data; Rats; Rats, Inbred WKY; Recombinant Proteins

To determine whether decreases in plasma antithrombin (AT) level, as seen in non-gestational acquired AT deficiency, result from a hypercoagulable state and/or liver/kidney damage, AT activity was measured in 24 uncomplicated and 30 preeclamptic women. The fifth percentile of AT levels in the normal pregnancies was used as a cut-off value to subdivide the preeclamptic patients into two groups. Markers of activated coagulation, i.e, levels of thrombin-antithrombin complex (TAT), fibrin D-dimer, soluble fibrin, von Willebrand factor (vWF) and platelet counts, were determined. Indicators of hepatic or renal function, i.e. concentrations of alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine, urinary albumin (U-albumin) and serum albumin (S-albumin), were assayed. AT levels were lower in those with preeclampsia than in the normal pregnancy group (P < 0.01). In the group with AT levels less than the cut-off point, levels of fibrin D-dimer (P < 0.05), soluble fibrin (P < 0.05), vWF (P < 0.05), ALT (P < 0.05), AST (P < 0.05), creatinine (P < 0.01) and U-albumin (P < 0.01) were increased, whereas platelet counts (P < 0.05) and S-albumin (P < 0.05) were decreased. All patients with ALT levels > 0.46 mu kat/1, AST > 0.58 mu kat/1, S-albumin < 23 g/1 and/or U-albumin > 4.9 g/24 h had AT levels < or = cut off. AT levels correlated with vWF (rs = - 0.73, P < 0.01) and creatinine (Rs = -0.70, P < 0.01). It is suggested that in preeclampsia, acquired AT deficiency is secondary to a hypercoagulable state, and/or associated with impaired hepatic and/or renal function.

Topics: Alanine Transaminase; Albuminuria; Antithrombin III; Antithrombin III Deficiency; Aspartate Aminotransferases; Creatinine; Female; Fibrin; Humans; Kidney; Liver; Peptide Hydrolases; Pre-Eclampsia; Pregnancy; Pregnancy Complications, Hematologic; Serum Albumin; von Willebrand Factor

We measured the plasma levels of fibrinogen, D-dimer, thrombin-antithrombin complex (TAT), plasmin-plasmin inhibitor complex (PPIC), soluble fibrin monomer (SFM), tissue-type plasminogen activator (t-PA) and thrombomodulin (TM) in patients with non-insulin-dependent diabetes mellitus (NIDDM). There were no significant differences in the hemostatic parameters between the 77 patients with NIDDM and healthy control subjects, although the plasma levels of fibrinogen, D-dimer, TAT, and PPIC in the NIDDM patients were slightly higher than those in the healthy controls. Among the NIDDM patients divided into three groups by the urinary albumin excretion (UAE) level, there was no significant difference in age or sex among the normo-, micro-, and macroalbuminuria groups, and the HbA1C level in the micro- and macroalbuminuria groups were slightly higher than those in the normoalbuminuria group. There was no significant difference in activated partial thromboplastin time, prothrombin time, fibrinogen, TAT, PPIC, D-dimer, or t-PA among these three groups. The plasma SFM and TM levels in the macroalbuminuria group were significantly higher than those in the normo- and microalbuminuria groups. The relationships between HbA1C and the hemostatic parameters were poor, but the plasma TM and SFM levels were significantly correlated with the urine albumin index.

Topics: Adult; Aged; Albuminuria; Diabetes Mellitus, Type 2; Female; Fibrin; Humans; Male; Middle Aged; Prothrombin Time; Thrombomodulin

The urinary concentration of fibrin-fibrinogen degradation products (F.D.P.) was measured in 90 patients with proteinuria above 2 g/1 and correlated with proteinuria, differential protein clearances, serum urea and creatinine, and renal biopsy findings. There was a linear correlation (r equals 0-7; P less than 0-001) between the urinary F.D.P. excretion and the selectivity of the proteinuria such that patients with highly selective proteinuria excreted only small amounts of F.D.P. whereas those with non-selective proteinuria excreted much higher levels. There was a significant correlation between the urinary F.D.P. excretion and the urine:serum (U:S) ratio of IgG excretion but not with the U:S ratio or urinary excretion of albumin or transferrin. Sephadex G200 column chromatography of the concentrated urine in 26 cases showed that patients with highly selective proteinuria excreted predominantly F.D.P. of low molecular weight in the urine whereas those with non-selective proteinuria excreted mainly fibrinogen and products of high molecular weight. Hence the type and quantity of F.D.P. in the urine are determined primarily by the differential filtration of fibrinogen and the various degradation products from the plasma through the glomerular basement membrane, which in turn is determined by the "pore size" of the basement membrane. In clinical nephrology measurement of the urinary F.D.P. level provides a rapid and convenient means of estimating the differential protein clearance.

Topics: Albuminuria; Amyloidosis; Chromatography; Fibrin; Fibrinogen; Filtration; Glomerular Filtration Rate; Glomerulonephritis; Humans; Hypersensitivity; Hypertension, Malignant; Immunodiffusion; Immunoglobulin G; Lupus Erythematosus, Systemic; Molecular Weight; Nephrotic Syndrome; Proteinuria; Purpura; Thrombosis; Transferrin

Topics: Adult; Albuminuria; Basement Membrane; Blood Pressure; Capillaries; Complement System Proteins; Creatinine; Female; Fibrin; Fluorescent Antibody Technique; Humans; Immune Sera; Immunoglobulin G; Kidney; Kidney Glomerulus; Lupus Erythematosus, Systemic; Male; Middle Aged; Renal Artery; Scleroderma, Systemic; Urea

Topics: Albuminuria; Animals; Chromatography, Gel; Chromatography, Ion Exchange; Fibrin; Fibrinogen; Glomerular Filtration Rate; Glomerulonephritis; Humans; Immunoelectrophoresis; Kidney Transplantation; Molecular Weight; Muramidase; Nephrosis; Plasminogen; Rabbits; Streptokinase; Transplantation, Homologous; Uremia

Topics: Albuminuria; Disseminated Intravascular Coagulation; Female; Fibrin; Fibrinogen; Humans; Pre-Eclampsia; Pregnancy

Topics: Albuminuria; Eclampsia; Edema; Female; Fibrin; Humans; Hypertension; Pre-Eclampsia; Pregnancy