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M Jandrot-Perrus

Publications and source records attributed to M Jandrot-Perrus.

41 records · Page 3Linked to original sources
PubMed1987

ADP-induced platelet aggregation depends on the conformation or availability of the terminal gamma chain sequence of fibrinogen. Study of the reactivity of fibrinogen Paris 1.

Fibrinogen Paris I contains a mutant gamma chain that is longer than the normal chain, resulting in altered fibrin polymerization and cross-linking. Because these functions involve the carboxy-terminal region of the gamma chain, we decided to determine whether fibrinogen Paris I or the isolated Paris I gamma chain supports normal ADP-induced platelet aggregation, a function that requires the ultimate 12 residues of the normal gamma chain (400 through 411). Aggregation of ADP-stimulated normal platelets was defective with fibrinogen Paris I and markedly depressed with the gamma Paris I chain. These findings prompted us to characterize the carboxy-terminal structure of the region of the gamma Paris I chain responsible for this activity. The carboxy-terminal cyanogen bromide (CNBr) peptide of the normal gamma chain (385 through 411) or that from gamma Paris I was isolated by differential adsorption to triethylene-tetramine resin or by reverse-phase high-performance liquid chromatography (HPLC). The CNBr peptide from the Paris I gamma chain was identical to that of the normal gamma chain in its retention time on HPLC, its amino acid composition, and its sequence. Thus, the primary structure of the gamma Paris I chain from residue 384 through 411 is normal, indicating that a peptide insertion has occurred upstream from residue 384, resulting in an impairment of those physiologic functions attributable to the carboxy-terminal end of the gamma chain from position 384 (ie, cross-linking, ADP-induced platelet aggregation, and at least a portion of the gamma chain polymerization site). These observations demonstrate that the gamma chain platelet recognition site in the fibrinogen molecule is necessary but not alone sufficient to support normal ADP-induced platelet aggregation. There appears to be an additional requirement for normal conformation of the gamma chain or availability of its terminal sequence during the interaction of fibrinogen with platelets.

Adenosine Diphosphate↗
PubMed1984

Thrombin Metz: characterization of the dysfunctional thrombin derived from a variant of human prothrombin.

Thrombin Metz and normal thrombin, resulting from activation of the respective prothrombins by factor Xa in the presence of calcium, phospholipid, and factor Va, were purified by chromatography on sulfopropyl Sephadex. By physicochemical criteria, thrombin Metz is identical to normal thrombin. Its functional properties were investigated in some reactions in which thrombin is classically involved. Thrombin Metz exhibits less than 4% of fibrinogen clotting activity. Both Km and Kcat, determined on S2238, are abnormal. Titration with the high-affinity competitive inhibitor of thrombin, DAPA, shows that fluorescence enhancement of the probe is only 34% in binding to thrombin Metz when compared to that observed in binding to normal thrombin. High-performance liquid chromatography has been used to measure the simultaneous rate of release of fibrinopeptides A and B. A decreased release rate for both fibrinopeptides, more marked for fibrinopeptide B, results in a slow fibrin polymerization, as followed by absorbance at 450 nm. Thrombin Metz is less than 5% as effective as normal thrombin in inducing platelet aggregation. Interaction with antithrombin III is slower than normal when followed by SDS gel electrophoresis and inhibition of the amidolytic activity of thrombin on S2238. This abnormality is not observed in the presence of heparin. However, thrombin Metz binds less tightly to a heparin-Sepharose column, and the direct inhibition of heparin on its activity on S2238 is weaker. From these results, we can predict that the defect in thrombin Metz affects the catalytic site or its vicinity and, jointly or consequently, the region of interaction of thrombin with antithrombin III and heparin.

Antithrombin III↗
PubMed1982

Fibrinogen Bondy: a new case of dysfibrinogenemia. Isolation of the abnormal fibrinogen molecules.

In a 81 year old health woman, gross abnormalities of fibrin formation led to the discovery of an abnormal fibrinogen named fibrinogen Bondy. Clottability of purified fibrinogen Bondy was only 53% compared to 95-98% for normal fibrinogen. Functional studies revealed (i) delayed coagulation by thrombin and batroxobin (Reptilase), (ii) incomplete release of fibrino-peptides A and B, (iii) poor fibrin monomer aggregation, (iv) delayed fibrin proteolysis by plasmin. Electrophoretic mobility of fibrinogen Bondy, its three chains and the products of fibrin cross-linking, was normal. Fibrinogen NH2-terminal residues of fibrinogen Bondy were found to be normal. The presence of Ala, in addition to Gly and Tyr in the fibrin clot and its supernatant, showed that a part of fibrinogen molecules was not clotted, i.e. either copolymerised with fibrin or remaining in solutions. Gel filtration of the supernatant allowed the separation of both soluble complexes and fibrinogen. This fibrinogen population was shown to be unclottable by thrombin and to inhibit clotting of normal fibrinogen.

Aged↗