Somatomedin C/insulin-like growth factor I: simplified purification procedure and biological activities of the purified growth factor

• Published in: Journal of endocrinology Vol. 110; no. 1; p. 151
• Main Authors: Morrell, D J, Ray, K P, Holder, A T, Taylor, A M, Blows, J A, Hill, D J, Wallis, M, Preece, M A
• Format: Journal Article
• Language: English
• Published: England 01-07-1986
• Subjects: Amino Acids - analysis; Biological Availability; Chromatography, Gel; Chromatography, High Pressure Liquid; Chromatography, Ion Exchange; Insulin-Like Growth Factor I - isolation & purification; Radioimmunoassay; Somatomedins - isolation & purification
• ISSN: 0022-0795
• DOI: 10.1677/joe.0.1100151

Human somatomedin C has been purified from Cohn fraction IV paste by a simplified procedure using chromatofocusing, hydroxylapatite chromatography and reverse-phase high performance chromatography. The purified material has a specific activity by somatomedin C radioimmunoassay of 9160 units/mg (1 unit is defined as the amount of somatomedin present in 1 ml normal adult male human serum), representing a 650,000-fold purification, and possesses sulphation, mitogenic and insulin-like activities (specific activities of 3388 units/mg, 832 units insulin equivalents/mg and 1122 units/mg respectively). Somatomedin C is shown to be a potent stimulator of DNA synthesis (50% maximum stimulation at 150 fmol/ml) in isolated chondrocytes derived from costal cartilage, a major physiological target tissue.