Intrarenal Localisation Of Platelet Related Antigens, PF4, β-TG, Fibrin And Factor VIII In Patients With Glomerulonephritis

1981 ◽  
Author(s):  
P Duffus ◽  
A Parbtani ◽  
G Frampton ◽  
J S Cameron

In vivo platelet activation is common in glomerular disease. A strone correlation between platelet serotonin depletion and the factors in the serum which affect platelet aggregation in vitro suggests that platelet activation predominantly occurs in the peripheral circulation. However, platelet activation could occur in the renal microvasculature resulting in the deposition of platelet related antigens at this site. We studied 88 biopsies by immunofluorescence microscopy for the presence of platelet membrane antigen(s), PF4, β-TG, fibrin and factor VIII. β-TG was not observed in any of the biopsies studied. Most biopsies (92%) showed positive endothelial fluorescence for factor VIII antigen, but were otherwise negative. Biopsies from patients with usually benign forms of glomerular disease (minimal change, focal and mesangial proliferative glomerulonephritis) were mostly negative; only 8% showing weakly positive fluorescence for platelet membrane antigens and PF4. Biopsies from patients with usually progressive forms of glomerulonephritis (MCGN, membranous nephropathy, PAN, SLE) were mostly positive (85%) for platelet membrane antigen(s) and PF4. A notable exception was biopsies from patients with FSGS; only two out of 11 biopsies (18%) were positive in this group of patients. The presence of platelet related antigens in glomerulonephritis suggests platelet activation and trapping at this site as well as in the peripheral circulation.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 3946-3946
Author(s):  
Yue Han ◽  
De Pei Wu ◽  
Lan Dai ◽  
Wenrong Sheng ◽  
Changgeng Ruan

Abstract Platelets play a crucial role in thrombosis, platelet activation induces an alteration of platelet membrane glycoproteins between the platelet surface and surface connected canalicular system (SCCS). In an attempt to better understand this process and assess its significance in the study of thrombosis disease, we used flowcytometry for detecting the redistribution of antigens on the platelet surface following activation. The expression of platelet membrane glycoproteins (GP) Ib, IIIa and P-selectin as well as the platelet agglutination induced by ristocetin were measured in 20 normal subjects, whose platelets were stimulated by the peptide SFLLRNP(TRAP, thrombin receptor activated peptide) at different time points (0~30minute). The same antigens were also analyzed in whole blood in 30 patients with cerebral infarction. As expected, a stable increase of P-selectin was obtained from 2 minute upon TRAP activation, while a reversible reduction of GPIbα and agglutinability by ristocetin were showed at the same time, with a maximum decrease at 2 minute, then followed by a return of GP Ibα to platelet surface. In addition, the platelet membrane GPIIIa was not significantly changed in the initial stage after platelet stimulation and increased by degrees 10 minutes later. Compared with those in normal group, there was an apparent increase of P-selectin and a lower expression of GPIb in the patients with cerebral infarction, while GPIIIa was not significantly changed in all the samples. In summary, TRAP can mediate platelet activation, which leads to the redistribution of GPIb and GPIIIa in a time-dependent manner, together with the release of P-selectin. Meanwhile, the change of activation-dependent antigens on the platelet surface could be an important index reflecting the platelet activation in vivo.


1969 ◽  
Vol 22 (03) ◽  
pp. 577-583 ◽  
Author(s):  
M.M.P Paulssen ◽  
A.C.M.G.B Wouterlood ◽  
H.L.M.A Scheffers

SummaryFactor VIII can be isolated from plasma proteins, including fibrinogen by chromatography on agarose. The best results were obtained with Sepharose 6B. Large scale preparation is also possible when cryoprecipitate is separated by chromatography. In most fractions containing factor VIII a turbidity is observed which may be due to the presence of chylomicrons.The purified factor VIII was active in vivo as well as in vitro.


1981 ◽  
Vol 45 (03) ◽  
pp. 285-289 ◽  
Author(s):  
J P Allain ◽  
A Gaillandre ◽  
D Frommel

SummaryFactor VIII complex and its interaction with antibodies to factor VIII have been studied in 17 non-haemophilic patients with factor VIII inhibitor. Low VIII:C and high VIIIR.Ag levels were found in all patients. VIII:WF levels were 50% of those of VTIIRrAg, possibly related to an increase of poorly aggregated and electrophoretically fast moving VIIIR:Ag oligomers.Antibody function has been characterized by kinetics of VIII :C inactivation, saturability by normal plasma and the slope of the affinity curve. Two major patterns were observed:1) Antibodies from 6 patients behaved similarly to those from haemophiliacs by showing second order inhibition kinetics, easy saturability and steep affinity slope (> 1).2) Antibodies from other patients, usually with lower titres, inactivated VIII :C according to complex order kinetics, were not saturable, and had a less steep affinity slope (< 0.7). In native plasma, or after mixing with factor VIII concentrate, antibodies of the second group did not form immune complexes with the whole factor VIII molecular complex. However, dissociation procedures did release some antibodies from apparently low molecular weight complexes formed in vivo or in vitro. For appropriate management of non-haemophilic patients with factor VIII inhibitor, it is important to determine the functional properties of their antibodies to factor VIII.


1974 ◽  
Vol 31 (03) ◽  
pp. 420-428 ◽  
Author(s):  
M Fainaru ◽  
S Eisenberg ◽  
N Manny ◽  
C Hershko

SummaryThe natural course of defibrination syndrome caused by Echis colorata venom (ECV) in five patients is reported. All patients developed afibrinogenemia within six hours after the bite. Concomitantly a depression in factor V was recorded. Factor VIII and thrombocyte count in blood were normal in most patients. In the light of the known effects of ECV on blood coagulation in vivo and in vitro it is concluded that the afibrinogenemia is due to intravascular clotting.Four patients had transient renal damage, manifested by oliguria, azotemia, albuminuria and cylindruria, ascribed to microthrombi in the renal glomeruli.After the bite, the natural course was benign, no major bleeding was observed, and all signs of coagulopathy reverted to normal within 7 days. Therefore we recommend no specific treatment for this condition. In the case of heavily bleeding patients, administration of antiserum against ECV and/or heparin should be considered.


1993 ◽  
Vol 70 (04) ◽  
pp. 676-680 ◽  
Author(s):  
H F Kotzé ◽  
V van Wyk ◽  
P N Badenhorst ◽  
A du P Heyns ◽  
J P Roodt ◽  
...  

SummaryPlatelets were isolated from blood of baboons and treated with neuraminidase to remove platelet membrane sialic acid, a process which artificially ages the platelets. The platelets were then labelled with 111In and their mean life span, in vivo distribution and sites of Sequestration were measured. The effect of removal of sialic acid on the attachment of immunoglobulin to platelets were investigated and related to the Sequestration of the platelets by the spleen, liver, and bone marrow. Removal of sialic acid by neuraminidase did not affect the aggregation of platelets by agonists in vitro, nor their sites of Sequestration. The removal of 0.51 (median, range 0.01 to 2.10) nmol sialic acid/108 platelets shortened their life span by 75 h (median, range 0 to 132) h (n = 19, p <0.001), and there was an exponential correlation between the shortening of the mean platelet life span and the amount of sialic acid removed. The increase in platelet-associated IgG was 0.112 (median, range 0.007 to 0.309) fg/platelet (n = 25, p <0.001) after 0.79 (median, range 0.00 to 6.70) nmol sialic acid/108 platelets was removed (p <0.001). There was an exponential correlation between the shortening of mean platelet life span after the removal of sialic acid and the increase in platelet-associated IgG. The results suggest that platelet membrane sialic acid influences ageing of circulating platelets, and that the loss of sialic acid may have exposed a senescent cell antigen that binds IgG on the platelet membrane. The antibody-antigen complex may then provide a signal to the macrophages that the platelet is old, and can be phagocytosed and destroyed.


1992 ◽  
Vol 67 (06) ◽  
pp. 660-664 ◽  
Author(s):  
Virgilio Evangelista ◽  
Paola Piccardoni ◽  
Giovanni de Gaetano ◽  
Chiara Cerletti

SummaryDefibrotide is a polydeoxyribonucleotide with antithrombotic effects in experimental animal models. Most of the actions of this drug have been observed in in vivo test models but no effects have been reported in in vitro systems. In this paper we demonstrate that defibrotide interferes with polymorphonuclear leukocyte-induced human platelet activation in vitro. This effect was not related to any direct interaction with polymorphonuclear leukocytes or platelets, but was due to the inhibition of cathepsin G, the main biochemical mediator of this cell-cell cooperation. Since cathepsin G not only induces platelet activation but also affects some endothelial cell functions, the anticathepsin G activity of defibrotide could help to explain the antithrombotic effect of this drug.


1976 ◽  
Vol 36 (01) ◽  
pp. 009-013 ◽  
Author(s):  
D. L Aronson

SummaryThrombin acts on several coagulant proteins to produce products with physiologic, pharmacologic and pathologic potential. The most sensitive thrombin substrate seems to be factor VIII. Some thrombin dependent reactions studied in vitro and proposed as control reactions seem too insensitive to the action of thrombin to be of in vivo significance.The only enzymic reaction the thrombin-like venom enzymes, Ancrod and Batroxobin, have in common with thrombin is the removal of fibrinopeptide A.


1993 ◽  
Vol 69 (01) ◽  
pp. 021-024 ◽  
Author(s):  
Shawn Tinlin ◽  
Sandra Webster ◽  
Alan R Giles

SummaryThe development of inhibitors to factor VIII in patients with haemophilia A remains as a serious complication of replacement therapy. An apparently analogous condition has been described in a canine model of haemophilia A (Giles et al., Blood 1984; 63:451). These animals and their relatives have now been followed for 10 years. The observation that the propensity for inhibitor development was not related to the ancestral factor VIII gene has been confirmed by the demonstration of vertical transmission through three generations of the segment of the family related to a normal (non-carrier) female that was introduced for breeding purposes. Haemophilic animals unrelated to this animal have not developed functionally significant factor VIII inhibitors despite intensive factor VIII replacement. Two animals have shown occasional laboratory evidence of factor VIII inhibition but this has not been translated into clinical significant inhibition in vivo as assessed by clinical response and F.VIII recovery and survival characteristics. Substantial heterogeneity of inhibitor expression both in vitro and in vivo has been observed between animals and in individual animals over time. Spontaneous loss of inhibitors has been observed without any therapies designed to induce tolerance, etc., being instituted. There is also phenotypic evidence of polyclonality of the immune response with variable expression over time in a given animal. These observations may have relevance to the human condition both in determining the pathogenetic factors involved in this condition and in highlighting the heterogeneity of its expression which suggests the need for caution in the interpretation of the outcome of interventions designed to modulate inhibitor activity.


1997 ◽  
Vol 77 (02) ◽  
pp. 383-386 ◽  
Author(s):  
S Bellucci ◽  
J P Girma ◽  
M Lozano ◽  
D Meyer ◽  
J P Caen

SummaryThe Bernard-Soulier syndrome (BSS) is characterized by thrombocytopenia with giant platelets, a prolonged bleeding time with defective platelet adhesion to the subendothelium related to a defect in platelet membrane glycoprotein lb (GPIb) and a decreased prothrombin consumption. The mechanism of the latter abnormality remains unknown. In this study, we showed that this defect was corrected by the addition of purified human factor VIII (FVIII) to blood from four patients with BSS. The correction of prothrombin consumption was almost complete at concentrations between 1.5 and 3 IU/ml of FVIII procoagulant activity (VIII.'C) and partially abolished by a monoclonal antibody which neutralizes VIII:C. This correction was specific for FVIII and was not observed after addition of purified human FIX. It was obtained, in the same magnitude range, with FVIII complexed to von Willebrand factor (vWF) but not with free vWF. These data provide a new insight into the knowledge of the physiological interaction between the platelet membrane and the vWF-FVIII complex facilitating plasma coagulation activation and may lead to helpful therapeutic advances.


1975 ◽  
Author(s):  
E. G. D. Tuddenham ◽  
A. L. Bloom ◽  
J. C. Giddings ◽  
C. A. Barrett

The occurrence of factor VIII inhibitor in five mild or moderately affected liaemophilic patients is described. In four patients the inhibitor inactivated endogenous factor VIII an dtemporarily converted them to severely affected haemophiliacs with factor VIII level of 0%. In the fifth patient, a brother of one of the others, the inhibitor although more potent did not inactivate the patient’s own factor VIII and did not completely inactivate normal factor VIII in vitro. This patient responded to treatment with factor-VIII concentrate but the in-vivo recovery was reduced. The patient’s plasma was tested against a panel of normal donors but it inactivated factor VIII in each to a similar extent and no evidence for normal factor-VIII groups was obtained. In the other patients the response to replacement treatment was also better than that usually seen in severely affected haemophilic patients with inhibitor. In the two related patients the inhibitors have so far persisted but in the unrelated patients the inhibitors eventually disappeared and did not always recur with subsequent therapy. The incidence of factor- VIII inhibitor in less severe haemophiliacs (factor VIII > 3% ) in this centre is 6% suggesting that the complication is more frequent in this type of patient than hitherto recognised.


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