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Biomedical subjects

M Goudemand

Publications and source records attributed to M Goudemand.

At least 55 records · Page 3Linked to original sources
PubMed1989

Properties of a highly purified human plasma factor IX:c therapeutic concentrate prepared by conventional chromatography.

We have characterized a highly purified (HP) factor IX concentrate intended for therapy of hemophilia B. The product has been prepared from pooled human plasma using a large-scale procedure combining three conventional chromatographic steps based on DEAE ion exchange and affinity on immobilized heparin. The specific activity of the product was 119 +/- 10 IU factor IX:c/mg protein (n = 15), corresponding to a purification factor of about 9,000. The concentrate was free of the vitamin K-dependent clotting factors II, VII and X and of proteins C and S. Most of the contaminants found in factor IX complex concentrate (PCC) were absent in this new product. High-molecular-weight kininogen, factors VIII, XI, XII or prekallikrein were not detected. There were no activated factors, such as factors IXa, and Xa, no thrombin and no phospholipids. Only two contaminants could be detected: C4 and inter-alpha-trypsin inhibitor (about 0.8 and 1.2 mg/1,000 IU factor IX:c, respectively). The purity of the product, as compared to PCC, was confirmed by sodium dodecylsulfate polyacrylamide gel electrophoresis, cellulose acetate electrophoresis, Grabar-Williams immunoelectrophoresis, and bidimensional immunoelectrophoresis. Thrombogenicity tests in rabbits revealed that the HP factor IX tested had a lower thrombogenic power than the PCC tested. The concentrate has been subjected to a 0.3% tri(n-butyl) phosphate-1% Tween 80 treatment for 6h at 25 degrees C during its production to reduce or eliminate the risk of transmission of plasma-borne lipid-enveloped viruses. These conditions inactivated more than 3.8 log10 of vesicular stomatitis virus and more than 4.3 log10 of sindbis virus within 1 and 2 h of treatment, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Coagulation Factors↗
PubMed1989

In vitro and in vivo characterization of a high-purity, solvent/detergent-treated factor VIII concentrate: evidence for its therapeutic efficacy in von Willebrand's disease.

A factor VIII (FVIII) concentrate, virus-inactivated by the solvent/detergent procedure, was studied in vitro. In contrast with most high-purity, virus-inactivated FVIII concentrates, it contains not only high levels of von Willebrand factor (vWF) antigen and ristocetin cofactor activity but also high molecular weight forms of von Willebrand factor. Furthermore, it is able to promote platelet adhesion on collagen in a perfusion system. In vivo studies performed in patients with different types of von Willebrand's disease provided evidence that this concentrate corrects Duke's bleeding time and prevents or stops haemorrhages. Thus, the particular advantages of this FVIII/vWF preparation are safety, low content of contamination proteins, and efficacy in von Willebrand's disease.

Antigens↗
PubMed1988

Functional and immunological assays of FVIII in 133 haemophiliacs--characterization of a subgroup of patients with mild haemophilia A and discrepancy in 1- and 2-stage assays.

A systematic study of the levels of FVIII antigen and activity was done in 133 haemophiliacs. No measurable antigen was demonstrated in the 60 severe haemophiliacs, with the exception of 3 patients with levels ranging between 1.5 and 4.5 U/dl, which corresponded to a dramatic FVIII deficiency. The situation was more complex with the 73 moderate and mild haemophiliacs: 39 of them (53.4%) had a partial, concordant deficiency of both the antigen and the procoagulant activity (1- and 2-stage methods), likely corresponding to a decrease in the synthesis of normal FVIII. The conclusion for the other 34 patients, was a qualitative abnormality of FVIII, the levels of antigen in comparison with the procoagulant activity (1-stage method) appearing to be either very reduced (n = 6) or even nil (n = 8), or on the contrary very much higher (n = 20) or normal. For 11 patients in this last category, we found a clear discrepancy between the procoagulant activity levels obtained with the 2 different techniques, the 1-stage levels being higher than the 2-stage levels. This discrepancy which was stable with restudy on multiple occasions and found in different members of the same families was remedied when vWF was absent in one-stage assay. This suggests that we have identified a variant of haemophilia A with an inherited abnormality of FVIII characterized by an in vitro vWF-dependent expression of procoagulant activity.

Aluminum Hydroxide↗
PubMed1988

Investigation of a large kindred with type IIB von Willebrand's disease, dominant inheritance and age-dependent thrombocytopenia.

Twenty-six members of four generations of one family in which a man was diagnosed in 1961 as having von Willebrand's disease (vWD) have been studied. Subtype IIB vWD and autosomal dominant inheritance was identified in 19 individuals with bleeding signs varying in severity and frequency. The absence of high molecular weight multimers of plasma von Willebrand factor (vWf) and the heightened interaction of plasma vWf with platelets in the presence of low ristocetin concentrations were consistent in all affected subjects. Nevertheless the degree of these abnormalities was variable without clearcut linkage to the severity of clinical symptoms. Thrombocytopenia was present only in the adult affected family members and the platelet count appeared to be age-dependent. The investigation of this family provides further evidence of the phenotypic variability in the vWf-platelet interactions within this vWD subtype.

Adolescent↗
PubMed1988

Large-scale production and properties of a solvent-detergent-treated factor IX concentrate from human plasma.

A human solvent-detergent (SD)-treated factor IX concentrate has been produced from cryoprecipitate-poor plasma using DEAE-Sepharose CL-6B and heparin-Sepharose CL-6B chromatography. The DEAE eluate was incubated with an SD mixture [0.3% tri(n-butyl) phosphate-1% Tween 80, 6-h at 24 degrees C] which was found to inactivate, in less than 1 h, more than 3.8 log10 of vesicular stomatitis virus and more than 4.8 log10 of Sindbis virus; the SD was removed by a subsequent heparin adsorption step. The specific activity of the concentrate was 10.9 +/- 1.3 IU factor IX: c/mg protein (n = 15). The factor IX coagulant to antigen ratio was 0.7 +/- 0.1. The concentrate was essentially free of factors II, VII and X, and protein C. The usual major contaminants of prothrombin complex concentrate (PCC) were absent: the concentrate contained about 94% alpha-1 proteins, and only 4 major proteins were resolved by SDS-PAGE (respective apparent molecular weight: 130, 86, 76 and 69 kilodaltons), and by crossed immunoelectrophoresis against an anti-PCC serum. The nonactivated partial thromboplastin time was equivalent to that of PCC; the product was devoid of factor IXa, of other activated procoagulant factors and of coagulant-active phospholipids (removed with SD in the heparin breakthrough fraction). Animal studies using the Wessler test and acute-toxicity test in rabbits revealed no adverse side effects. SD treatment could thus be used to inactivate viruses in factor IX concentrate and improve the safety of replacement therapy in hemophilia B.

Adsorption↗
PubMed1987

Characterisation of a monoclonal antibody to von Willebrand factor as a potent inhibitor of ristocetin-mediated platelet interaction and platelet adhesion.

We studied a murine monoclonal antibody (211 A6) to von Willebrand factor (vWF) with a view to investigating structure-relationship of plasma vWF. The specificity of this antibody has been substantiated by ELISA tests and indirect immunofluorescence. It reacts with purified vWF, normal plasma but not with plasma or platelets from a severe von Willebrand's disease patient. Monoclonal antibody 211 A6 is a potent inhibitor of ristocetin-induced platelet aggregation. The 125I-FVIII/vWF binding to platelets in presence of ristocetin is totally inhibited by low 211 A6 concentrations. Thrombin-induced binding of vWF to platelets is not affected by 211 A6. The ability of this antibody to inhibit platelet adhesion to subendothelium and to collagen was investigated with a perfusion model. The complete inhibition of platelet adhesion by 211 A6 questions the similarity or the interrelationship in vWF domains involved in ristocetin-induced platelet functions and platelet adhesion.

Animals↗
PubMed1987

In vitro and in vivo evaluation of a factor VIII concentrate heat-treated to inactivate HTLV-III/LAV viruses. Favourable effects of heating on the von Willebrand factor.

We report here the results of our evaluation of the effects of a dry heat treatment (96 h at 68 degrees C) to eliminate LAV/HTLV-III virus on factor VIII (FVIII) and von Willebrand factor (vWf) present in an intermediate-purity concentrate. This thermal inactivation appears to have little effect on FVIII. There is an acceptable loss (12.3 +/- 3.6%; n = 25) in FVIII coagulant activity (FVIII: C) and a good in vivo performance in haemophilia A patients. A precise analysis of vWf indicates that whereas the vWf antigen and its ristocetin cofactor activity decrease during heating, there is an increase in potentially functional forms of vWf. Heat treatment induces an increase in high molecular weight forms of vWf and an enhancement in platelet adhesion to collagen. These changes probably explain the correcting effect on the bleeding time of the heated FVIII concentrate in patients with von Willebrand's disease. Thus, this heat-treated concentrate appears to be equivalent to the untreated product in haemophilia A, with the additional benefit of being efficient for the treatment of von Willebrand's disease.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Biochemical and biological properties of an alpha 1-antitrypsin concentrate.

alpha 1-Antitrypsin (AAT) has been purified from human plasma supernatant A (equivalent to COHN fraction II + III) by a large-scale chromatographic procedure involving anion-exchange adsorption on DEAE Sepharose CL-6B fast flow and size-exclusion chromatography on Sephacryl S-200. Before freeze-drying, the liquid concentrate was heat-treated at 60 degrees C for 10 h to reduce the risk of transmission of blood-born viral diseases. Using this procedure, AAT is recovered with 80-90% purity in 65-75% yield from supernatant A. The heterogeneity of AAT is preserved across the purification steps. In addition, purified AAT exhibits inhibitory activities against trypsin and elastase equivalent to that of the serum protein. The mean association rate constant for elastase was found as high as 2.15 X 10(5) M-1 s-1. Thus, purifying active AAT from supernatant A contributes to improving the availability of this protein which may be potentially useful in the treatment of hereditary emphysema.

Chromatography, DEAE-Cellulose↗
PubMed1987

Large scale chromatographic purification of alpha 1-antitrypsin from human plasma supernatant II + III.

We describe a large-scale chromatographic method to purify alpha 1-antitrypsin (AAT) from human plasma supernatant II + III. Supernatant II + III was injected onto DEAE sepharose CL 6B to get an albumin-rich fraction as well as a fraction that contained about 45% AAT. This intermediate purity AAT fraction was further purified by size-exclusion chromatography on Sephacryl S-200. The product was heated in solution at 60 degrees C for 10 hours in the presence of a stabilizer to lower the risk of transmission of viral diseases. Purity of the AAT concentrate is over 85%; clinical testing of its safety and efficacy in the treatment of PiZ patients is underway.

Blood Proteins↗
PubMed1987

[Virus inactivation in plasma fractions for therapeutic use].

Methods to inactivate (or eliminate) viruses must be developed to ensure the safety of blood plasma fractions. For that purpose, dry or liquid heat treatment, solvent/detergent mixtures, beta-propiolactone/ultraviolet treatment, and chromatographic methods are the main procedures in use to date.

Blood↗
PubMed1986

Primary structure of a new tetraantennary glycan of the N-acetyllactosaminic type isolated from human factor VIII/von Willebrand factor.

N-Glycosidically linked glycopeptides released by mild alkaline treatment of human factor VIII/von Willebrand factor (FVIII/vWF) were fractionated by serial affinity chromatography on columns of Sepharose linked to concanavalin A (ConA) and Lens culinaris agglutinin (LCA). The fraction which is not retained on ConA-Sepharose, but eluted from LCA-Sepharose contains a pure minor glycopeptide which was structurally analysed. Based on the results of methylation analysis and 500-MHz 1H-NMR spectroscopy, the following structure is proposed: (Formula: see text).

Amino Acid Sequence↗
PubMed1986

Improved characterization of plasma von Willebrand factor heterogeneity when using 2.5% agarose gel electrophoresis.

Discontinuous sodium dodecyl sulfate electrophoresis in large pore gels, followed by overlay with radiolabelled anti-von Willebrand factor (vWF) antibodies and by autoradiography, permits to analyze the multimeric structure of vWF. The aim of this study was to improve experimental conditions of this technique to satisfactorily resolve the minor forms of plasma vWF while still separating its high, intermediate, and low molecular weight predominant multimers. By using a 2.5% mixture of two selected agaroses, a single electrophoretic analysis of plasma clearly reveals the extreme complexity of the molecular forms of circulating vWF: each multimeric unit of plasma vWF may be separated into five bands, the central one being predominant. The multimeric distribution and "quintuplet" pattern obtained in the electrophoretic system described here permit a convenient classification of the different subtypes of von Willebrand's disease.

Electrophoresis, Agar Gel↗
PubMed1986

Investigation of a case of subtype IIC von Willebrand disease: characterization of the variability of this subtype.

A variant of von Willebrand disease (vWD) has been identified in a 19-year-old woman with a severe bleeding syndrome. She had a very prolonged bleeding time (over 20 min), 24 U/dl factor VIII coagulant activity (F.VIII:C), 16 U/dl von Willebrand factor antigen (vWF:Ag), no ristocetin cofactor activity, and an anodal mobility of vWF:Ag on crossed immunoelectrophoresis (CIE). vWF:Ag was markedly reduced in her platelet lysate. In plasma and platelets, SDS-agarose electrophoresis consistently demonstrated the absence of large multimers, a relatively increased concentration of the fastest-moving multimer, and gross abnormalities of the internal structure of each vWF multimeric unit. Five members from the maternal side of the family had a double vWF:Ag peak by CIE and a relative increase of the fastest-moving vWF multimer by SDS-agarose electrophoresis; no quantitative or qualitative vWF defects were found in the paternal side of the family. The pattern of the findings in the propositus and her family is similar to those of type IIC vWD. However, there are some unique characteristics suggesting phenotypic variability in this subtype, such as low level of platelet vWF:Ag and the absence of increase of vWF after DDAVP administration.

Adult↗