epidermal-growth-factor and Thrombosis

Genetic defects in the protein C pathway are associated with an increased risk for venous thrombosis. This review will focus on the nature of the defects in the protein C gene that underlie protein C deficiency and the relationship with thrombotic disease.

Topics: Catalysis; Epidermal Growth Factor; Mutation; Peptides; Protein C; Protein C Deficiency; Protein Precursors; Protein Structure, Tertiary; Thrombosis

Topics: Epidermal Growth Factor; Glycosylation; Humans; Mutation; Protein C; Thrombin; Thrombosis

Several genes are expressed in aspirated coronary thrombi in acute myocardial infarction (AMI), exhibiting dynamic changes along ischemic time. Whether soluble biomarkers reflect the local gene environment and ischemic time is unclear. We explored whether circulating biomarkers were associated with corresponding coronary thrombi genes and total ischemic time.. In 33 AMI patients undergoing percutaneous coronary intervention (PCI), blood samples were collected within 6-24h for markers related to plaque rupture (metalloproteinase 9, tissue inhibitor of metalloproteinases 1), platelet and endothelial cell activation (P-selectin, CD40 ligand, PAR-1), hemostasis (tissue factor, tissue plasminogen activator, plasminogen activator inhibitor 1, free and total tissue factor pathway inhibitor, D-dimer, prothrombin fragment 1+2), inflammation (interleukin 8 and 18, fractalkine, monocyte chemoattractant protein 1 (MCP-1), CXCL1, pentraxin 3, myeloperoxidase) and galectin 3, caspase 8 and epidermal growth factor (EGF). Laboratory analyses were performed by Proximity Extension Assay (Proseek Multiplex CVD I(96 × 96)), ELISAs and RT-PCR.. Only circulating P-selectin correlated to the corresponding P-selectin gene expression in thrombi (r=0.530, p=0.002). Plasma galectin 3, fractalkine, MCP-1 and caspase 8 correlated inversely to ischemic time (r=-0.38-0.50, all p <0.05), while plasma MCP-1, galectin 3 and EGF were higher at short (≤ 4 h) vs. long (>4h) ischemic time (all p <0.05).. The dynamic changes in circulating mediators along ischemic time were not reflected in the profile of locally expressed genes. These observations indicate a locally confined milieu within the site of atherothrombosis, which may be important for selective therapy.

Topics: Adult; Aged; Biomarkers; Blood Platelets; Blood Proteins; Caspase 8; Chemokine CCL2; Chemokine CX3CL1; Cohort Studies; Coronary Thrombosis; Epidermal Growth Factor; Female; Galectin 3; Galectins; Gene Expression Regulation; Humans; Male; Middle Aged; Myocardial Infarction; P-Selectin; Percutaneous Coronary Intervention; Thrombosis; Time Factors

The thrombolytic activity of a novel modified tissue-type plasminogen activator (t-PA) (E6010) was examined in a canine model with copper coil-induced femoral artery thrombus. This model, in which thrombolytic activity can be easily and directly quantified by determining changes in thrombus weight, should be useful for comparing the activities of various thrombolytic agents. Using this model, the present study showed that the thrombolytic activity of bolus intravenous injection of E6010 was identical to that of continuous intravenous infusion of recombinant t-PA at the same dose. This thrombolytic activity can be explained by changes in blood concentrations of the administered thrombolytic agents. On the other hand, administration of the thrombolytic agents dose-dependently caused significant changes in the levels of hemostatic and fibrinolytic factors. These changes were not so marked with administration of E6010, and therefore we concluded that E6010 is unlikely to cause bleeding complications after administration.

Topics: Animals; Disease Models, Animal; Dogs; Dose-Response Relationship, Drug; Epidermal Growth Factor; Femoral Artery; Fibrinolytic Agents; Hemostasis; Injections, Intravenous; Recombinant Proteins; Thrombosis; Tissue Plasminogen Activator

A 29-year-old female patient with heterozygous congenital protein S deficiency suffering from thrombotic disease had normal levels of both total and free protein S antigen (70% and 65%, respectively), but low cofactor activity (31%) for activated protein C, indicating that she had a variant of protein S, protein S Tokushima. Western blotting using the polyclonal anti-protein S antibody showed that approximately half of the patient's protein S appeared to be the variant with a higher molecular weight than normal protein S. The partially purified variant protein S bound neither to the monoclonal antibody recognizing calcium-dependent conformation of protein S nor to the antibody recognizing the thrombin-sensitive domain of protein S. Among the exons from II to XV of the patient's protein S gene encoding from the NH2-terminal end to the COOH-terminal end of protein S, only one missense mutation (A to G) was found in exon VI of the protein S alpha-gene, which results in amino acid substitution of Glu(GAG) for Lys-155(AAG) in the second epidermal growth factor-like domain of protein S. The recombinant protein S Tokushima expressed in BHK cells had a slightly higher molecular weight than the recombinant normal one, did not bind to the antibody specific for the thrombin-sensitive domain, and did not show the cofactor activity. These findings suggest that the protein S Tokushima molecule is structurally and functionally a variant of protein S, and that this variant protein S is the cause of severe thrombosis in this patient.

Topics: Adult; Amino Acid Sequence; Base Sequence; Epidermal Growth Factor; Exons; Female; Humans; Introns; Molecular Sequence Data; Mutation; Protein Conformation; Protein S; Protein S Deficiency; Recombinant Proteins; Thrombosis

No consensus has been obtained about the question whether autoantibodies, in particular antiphospholipid antibodies (aPL), may cause thrombosis by inhibiting thrombomodulin (TM) mediated protein C activation. In order to clarify the mechanism by which autoantibodies inhibit TM-mediated protein C activation, we have screened 12 patients with autoimmune diseases for the presence of circulating autoantibodies inhibiting TM function. In a cross-sectional study we found that IgG fractions from two patients (who were aPL negative) inhibited TM mediated protein C activation in an assay system using purified components. A longitudinal study of six patients with a history of thrombosis of which two were aPL positive showed that all had at some time circulating antibodies inhibiting TM function, suggesting that the presence of these antibodies is transient. Three different TMs were used to identify the epitope of the antithrombomodulin antibodies (aTM): rabbit TM, which contains the entire TM molecule; Solulin, which contains the extracellular part of TM, and rEGF-TM, which contains the six epidermal growth factor (EGF) domains of TM. We showed that the aTM inhibited protein C activation mediated by all three TMs, indicating that the aTM are directed against the region containing the EGF domains. When TM was incorporated in phospholipid vesicles, no inhibition by these aTM could be demonstrated. In addition, protein C activation mediated by cultured endothelial cells (EC) could not be inhibited by aTM. The lack of inhibition of TM in phospholipid vesicles and EC-TM by a TM suggests that aTM only inhibit soluble TM. In conclusion, we demonstrated the transient presence of circulating autoantibodies directed against the region of TM containing the EGF domains in SLE patients with a history of thrombotic complications. We postulate that the presence of antibodies to soluble TM may be, in addition to aPL, a risk factor for the occurrence of thrombosis in patients with autoimmune diseases.

Topics: Adult; Autoantibodies; Autoimmune Diseases; Cross-Sectional Studies; Enzyme-Linked Immunosorbent Assay; Epidermal Growth Factor; Epitopes; Female; Humans; Immunoglobulin G; Longitudinal Studies; Male; Middle Aged; Protein C; Protein C Inhibitor; Thrombomodulin; Thrombosis