Jerdan J A, Varner H H, Greenberg J H, Horn V J, Martin G R
J Cell Biol. 1985 May;100(5):1493-8. doi: 10.1083/jcb.100.5.1493.
A protein (Mr = 63,000) from calf serum that promotes the pigmentation of cultured chick neural crest and mouse melanoma cells has been partially isolated and characterized in this study. The stimulation of melanin synthesis in cultured cells was used to follow its activity during purification. The pigment-promoting factor was isolated by sequential column chromatography on dye-agarose matrices followed by hydroxyapatite and high pressure molecular sieve chromatography. The factor was found to stimulate melanin biosynthesis at 2-4 micrograms/ml and was specific for melanin-producing cells and their precursors. Antibodies raised in rabbits against the factor inhibited its pigment-promoting activity as well as that of whole calf serum. Enzyme-linked immunoadsorbent assays demonstrated that calf and bovine sera contain molecules that cross-react with the pigment-promoting factor. Horse, human, rat, and chicken sera, which lack the biological activity, also lacked immunological cross-reactivity. Extracts of certain tissues, particularly the submaxillary gland, were observed to be rich sources of pigment-promoting activity.
本研究已对一种来自小牛血清的蛋白质（相对分子质量为63,000）进行了部分分离和特性鉴定，该蛋白质可促进培养的鸡神经嵴细胞和小鼠黑色素瘤细胞的色素沉着。利用培养细胞中黑色素合成的刺激作用来追踪其在纯化过程中的活性。通过依次在染料琼脂糖基质、羟基磷灰石和高压分子筛上进行柱色谱，分离出了色素促进因子。发现该因子在2 - 4微克/毫升时可刺激黑色素生物合成，并且对产生黑色素的细胞及其前体具有特异性。用兔制备的针对该因子的抗体可抑制其色素促进活性以及全小牛血清的色素促进活性。酶联免疫吸附测定表明，小牛和牛血清中含有与色素促进因子发生交叉反应的分子。缺乏生物活性的马、人、大鼠和鸡血清也缺乏免疫交叉反应性。观察到某些组织的提取物，特别是颌下腺，是色素促进活性的丰富来源。
