ESTABLISHMENT OF A HIGHLY SENSITIVE LEPTIN RADIOIMMUNOASSAY AND DETECTION OF INCREASED LEPTIN LEVELS IN HYPERLIPIDEMIA AND PREGNANCY

• Published in: Journal of immunoassay & immunochemistry 2002, Vol.23 (3), p.317-326
• Main Authors: Yan, Guang-Tao, Hao, Xiu-Hua, Xue, Hui, Lu, Yan-Ping
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Age Factors; Aged; Animals; Body Weight; Case-Control Studies; Circadian Rhythm; Female; Humans; Hyperlipidemias - blood; Hyperlipidemias - diagnosis; Immune Sera; Infant, Newborn; Leptin - blood; Leptin - immunology; Male; Middle Aged; Obesity - blood; Pregnancy; Rabbits; Radioimmunoassay - methods; Radioimmunoassay - standards; Reproducibility of Results; Sensitivity and Specificity
• ISSN: 1532-1819; 1532-4230
• DOI: 10.1081/IAS-120013031

The highly effective antibody has been obtained by immunizing rabbits with recombinant leptin many times. The leptin is iodinated with the chloramine-T method and purified with a Sephadex-G25 chromatography column. The reaction between antigen and antibody is carried out by a one-step balance method and cultured at 4°C for 24 h; the binding and free antigen was then separated by PR reagent. The determining range of this method is about 0.5-24 ng/mL; limited detection level is 0.45 ng/mL, relative standard deviation in a group, and among groups, are less than 5.4% and 8%, respectively. The level of blood leptin in 277 samples of normal persons, in 112 samples of overweight persons (weight/hieght m 2 ≥ 25) and 224 samples of hyperlipidemic patients have been measured by this method. It is demonstrated that the level of blood leptin in males is much lower than that of the females, and becomes elevated with increased age. Serum leptin level in overweight persons and hyperlipidemic patients is also much higher than that of normal groups (P