Matsuhashi S
Jpn J Exp Med. 1985 Apr;55(2):45-51.
It was found that white and yolk of the egg stimulated DNA synthesis of chick embryo epidermal culture. The epidermis cultured with yolk grew well in a manner similar to that with chick embryo extract, but the culture with egg white was poorer in growth than that with yolk. The mitogenic activity of egg white was inactivated by a heat treatment at 70 degrees C, while yolk was more heat-resistant. A heat-stable yolk fraction (hY fraction) which stimulated DNA synthesis of chick embryo epidermis was isolated by heat treatment at 98 degrees C. The mitogenic activity was enhanced by the addition of both egg white and hY fraction in the culture medium. The enhancement of epidermal growth by such an addition was confirmed by histological observations of the cultured epidermis. In embryonic skin, the growth and differentiation of epidermis is influenced by the nature of mesenchyme is proximity to the epidermal cells. The epidermis isolated from dermis does not grow or differentiate when cultivated in a chemically defined medium, although the tissue in whole skin does grow in the same medium. However, the isolated epidermis proliferates on non-living substrate such as membrane filter or collagen gel when cultured in a medium which contains chick embryo extract. This epidermal growth promoting property of chick embryo extract is inactivated by heat treatment or trypsin digestion.(ABSTRACT TRUNCATED AT 250 WORDS)
研究发现，鸡蛋的蛋白和蛋黄可刺激鸡胚表皮培养物的DNA合成。用蛋黄培养的表皮生长良好，其生长方式与用鸡胚提取物培养的相似，但用蛋白培养的生长情况比用蛋黄培养的差。蛋白的促有丝分裂活性在70℃热处理后失活，而蛋黄更耐热。通过98℃热处理分离出一种刺激鸡胚表皮DNA合成的热稳定蛋黄组分（hY组分）。在培养基中添加蛋白和hY组分均可增强促有丝分裂活性。通过对培养表皮的组织学观察证实了这种添加对表皮生长的促进作用。在胚胎皮肤中，表皮的生长和分化受邻近表皮细胞的间充质性质的影响。从真皮分离的表皮在化学限定培养基中培养时不会生长或分化，尽管全皮组织在相同培养基中会生长。然而，当在含有鸡胚提取物的培养基中培养时，分离出的表皮会在诸如膜滤器或胶原凝胶等无生命底物上增殖。鸡胚提取物的这种促进表皮生长的特性可通过热处理或胰蛋白酶消化使其失活。（摘要截选至250字）
