Role of haptoglobin subunits in their biological function

• Main Author: 林宏輝
• Other Authors: 毛仁淡
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/04461527913892750309

碩士 === 國立交通大學 === 生物科技系所 === 93 === Sterile tissue injury or infection initiates a local inflammatory response that mobilizes a systemic acute phase plasma proteins (APPs). Haptoglobin (Hp), one of the major APPs, has many important functions. A number of biological functions of Hp have been evaluated, such as high-affinity hemoglobin binding activity, antioxidant property, anti-inflammatory property, and angiogenesis. These functions of Hp are very important, especially hemoglobin binding activity and antioxidant property. While hemolysis occurs in the artery, the oxidative stress will be elevated to promote the initiation of LDL oxidation and destruction of vascular endothelium. Following the internalization of oxidative LDL particles in macrophages through specific scavenger receptors, the accumulation of oxidized LDL initiates the formation of atherosclerosis. Therefore, Hp may serve as an important role in prevention of atherosclerosis due to its potent antioxidant property. Hp is an acute phase protein which is composed of α and β subunits. The purpose of this study is to explore and evaluate what subunits contribute functions of Hp. The disulfide-linked cysteines of Hp were first reduced followed by gel-filtration chromatography to isolate α and β subunits. With respect to biological function of Hp, β subunit contributed the greater part of functions of Hp. According to this result, many functions of Hp were offered by β subunit.