Vitronectin is a plasma glycoprotein that circulates in the blood at a concentration range of 200 to 400 mg/ml constituting 0.2 to 0.5% of total plasma proteins (1,2). It is detected as a mixture of both 75 kDa and 65 kDa forms (3). The 65 kDa form is a product of proteolytic processing of the former which appears to be endogenously present. Vitronectin is involved in a number of physiological processes that include blood coagulation, fibrinolysis, complement cascade, and cell adhesion. Vitronectin (Serum spreading factor) is one of the two major cell-adhesive glycoproteins. It is a major ligand for the vitronectin receptor (αV/β3) or αV/β5 integrin on adhesive cells (4). Other functions include heparin-binding; collagen-binding; osteonectin-binding; complement lysis inhibitor and “scavenger” protein for macromolecular products of the complement and haemostasis cascade systems (5). It also functions as a substrate for trans glutaminase (Factor XIIIa) crosslinking, cAMP-dependent protein kinase, and tyrosyl protein sulfotransferase (4,5). Vitronectin has implications for thrombosis due to its heparin binding properties. It has been postulated that vitronectin prevents the acceleration of clot formation inhibition by acting as a heparin scavenger ultimately protecting thrombin and factor Xa from heparin-dependant inactivation by antithrombin III or heparin cofactor II (6,7). Vitronectin is also thought to play an important role in fibrinolysis by its ability to bind active PAI-1 (4). Extracellular binding of vitronectin to plasminogen activator inhibitor-1 (PAI-1) and plasminogen, stabilize the inhibitor and thus affect tissue plasminogen activator-mediated plasmin formation (4).

The vitronectin domain structure starting at the NH4-terminus consists of a somatomedin-B region (residues 1 to 44), a connecting segment containing the major cell attachment RGD sequence (residues 45 to 47) and a highly acidic region (residues 53 to 64), followed by hemopexin-like repeats (homology to hemopexin which is a heme-binding plasma protein), a glycosaminoglycan-binding site which is represented by a 40-amino acid stretch rich in basic residues, a protease-sensitive region susceptible to high concentrations of thrombin, and a COOH-terminal protein kinase A-dependent phosphorylation site, which is adjacent to the protease cleavage site (4,5).

Human vitronectin is prepared from fresh frozen plasma similar to the procedure described by Yatohgo and coworkers (8). Purified vitronectin is supplied in 50 mM sodium phosphate, 150 mM NaCl, pH 7.4 and should be stored at -80°C. Purity is assessed by SDS-PAGE analysis.

Haemtech Biopharma可以运行多种分析技术，以提供对蛋白质药物产品或物质的生化分析，或帮助进行污染物鉴定。我们的测定，测试和技术菜单包括：应用领域IVIG药物的血栓形成性过程中杂质分析与止血有关的抗药物抗体测试（免疫原性）例如抗凝血因子抗体宿主细胞蛋白质的鉴定，定量和缓解在制品和在制品中药品的稳定性和释放测试与止血相关的重组蛋白的效力和纯度测定血浆蛋白分析蛋白质的结构表征翻译后修饰二硫键映射构象变化凝血测定试剂（例如凝血活酶）的表征定制的凝血产品检测应用药代动力学研究分析鉴定/验证工艺/产品验证蛋白质纯化方法的发展强迫降解研究方法高效液相色谱反相（RPC）大小排除（SEC）离子交换（IEC）疏水相互作用（HIC）金属亲和力（IMAC）蛋白质A（用于IVIG分析）SDS页面减少和不减少一维和二维考马斯亮蓝染色银染荧光染色免疫印迹多重分析定量化凝血测定因子分析（II，V，VII，VIII，IX，X，XI，XII，XIII等）PTPTPT行动计划福尔摩斯测试其他ELISA法各种显色测定因子分析（II，V，VII，VIII，IX，X，XI，XII，XIII等）其他翻译后修饰分析糖基化，硫酸化，磷酸化，羟基化，脱酰胺，乙酰化，氧化，氨基甲酸酯化和γ-羧化凝血酶生成测定对于IVIG和其他抗药物抗体ELISA（ADA）抗原料药抗体抗宿主细胞蛋白的抗体抗污染物或分解产物的抗体鉴定未知质谱N端测序残留水分测定顶空真空测量pH值渗透压折光率总蛋白质配方评估