ovalbumin and Thrombosis

Both environmental and genetic factors are important in the development of antiphospholipid antibodies (aPL) in patients with antiphospholipid syndrome (APS). Currently, the only available data on predisposing genetic factors have been obtained from epidemiologic studies, without mechanistic evidence. Therefore, we studied the influence of major histocompatibility complex (MHC) class II alleles on the production of aPL in a mouse model of APS.. Three groups of mice, MHC class II-deficient (MHCII. Immunization with β. Our mechanistic study is the first to show that MHC class II alleles influence not only quantitative aPL production but also the pathogenic capacity of induced aPL.

Topics: Alleles; Animals; Antibodies, Anticardiolipin; Antibodies, Antiphospholipid; beta 2-Glycoprotein I; Carotid Arteries; Disease Models, Animal; Genes, MHC Class II; HLA-DQ Antigens; HLA-DR4 Antigen; Humans; Immunization; Immunoglobulin G; Macrophages; Macrophages, Peritoneal; Mice; Mice, Knockout; Mice, Transgenic; Ovalbumin; Severity of Illness Index; Thrombosis; Tumor Necrosis Factor-alpha

Annexin V is a human phospholipid binding protein that binds to activated platelets in vitro. We sought to determine the potential of this agent for imaging intracardiac thrombi in swine.. Left atrial thrombi were formed by crush injury. In initial nonimaging experiments using intravenous 125I-labeled human annexin V, the mean thrombus/whole blood ratio was 13.4 +/- 4.8 for the entire thrombus using well counting of resected specimens (n = 8). Using intravenously injected 99mTc-labeled human annexin V, the left atrial thrombus/blood ratio by well counting was similar (14.2 +/- 10.6 for the entire thrombus and 26.2 +/- 14.9 for the peak section) (n = 12). The ratio for a control protein, 125I-ovalbumin, was only 1.0 +/- 0.2. 99mTc tomographic imaging was positive (n = 10) or equivocal (n = 2) in all experiments with but negative in 10 controls without left atrial thrombi. By region-of-interest analysis of the tomographic images, the mean left atrial appendage/blood ratio at 2 hours in animals with a thrombus was 3.90 +/- 1.12 compared with 0.84 +/- 0.10 in closed chest controls and 1.01 +/- 0.23 in open chest controls (P < .001).. We conclude that 99mTc-labeled human annexin V detects acute left atrial thrombi in vivo in swine. The combination of a new thrombus detection agent, annexin V, with a 99mTc label may allow in vivo imaging of thrombi in humans.

Topics: Animals; Annexin A5; Feasibility Studies; Female; Heart; Heart Atria; Heart Diseases; Humans; Iodine Radioisotopes; Isotope Labeling; Male; Ovalbumin; Radionuclide Imaging; Swine; Technetium; Thrombosis

Six different substitution mutations were identified in four different amino acid residues of antithrombin strand 1C and the polypeptide leading into strand 4B (F402S, F402C, F402L, A404T, N405K, and P407T), and are responsible for functional antithrombin deficiency in seven independently ascertained kindreds (Rosny, Torino, Maisons-Laffitte, Paris 3, La Rochelle, Budapest 5, and Oslo) affected by venous thromboembolic disease. In all seven families, variant antithrombins with heparin-binding abnormalities were detected by crossed immunoelectrophoresis, and in six of the kindreds there was a reduced antigen concentration of plasma antithrombin. Two of the variant antithrombins, Rosny and Torino, were purified by heparin-Sepharose and immunoaffinity chromatography, and shown to have greatly reduced heparin cofactor and progressive inhibitor activities in vitro. The defective interactions of these mutants with thrombin may result from proximity of s1C to the reactive site, while reduced circulating levels may be related to s1C proximity to highly conserved internal beta strands, which contain elements proposed to influence serpin turnover and intracellular degradation. In contrast, s1C is spatially distant to the positively charged surface which forms the heparin binding site of antithrombin; altered heparin binding properties of s1C variants may therefore reflect conformational linkage between the reactive site and heparin binding regions of the molecule. This work demonstrates that point mutations in and immediately adjacent to strand 1C have multiple, or pleiotropic, effects on this serpin, leading ultimately to failure of its regulatory function.

Topics: Adolescent; Adult; Amino Acid Sequence; Antithrombins; Base Sequence; Binding Sites; Consensus Sequence; Heparin; Humans; Male; Middle Aged; Models, Molecular; Molecular Sequence Data; Mutation; Oligodeoxyribonucleotides; Ovalbumin; Pedigree; Protein Structure, Tertiary; Thrombosis; Trypsin Inhibitors

Topics: Aged; Animals; Chlorides; Dogs; Gastrointestinal Motility; Humans; Ileum; Intestinal Absorption; Intestinal Mucosa; Lymphatic System; Lymphocytes; Male; Ovalbumin; Permeability; Postoperative Complications; Radiography; Regeneration; Thrombosis; Transplantation, Autologous; Water

Topics: Anaphylaxis; Animals; Capillaries; Diphenhydramine; Electrons; Ferritins; Guinea Pigs; Hypersensitivity; Immune System Phenomena; Lung; Microscopy; Microscopy, Electron; Ovalbumin; Pharmacology; Research; Thrombosis