Density-dependent variations in the lipid content and metabolism of cultured human keratinocytes.
Density-dependent variations in the lipid content and metabolism of cultured human keratinocytes.
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培养的人角质形成细胞的脂质含量和代谢的密度依赖性变化。
DOI：
10.1111/1523-1747.ep12463297
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
Elias,PM
中科院分区：
文献类型：
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作者：
Williams,ML;Rutherford,SL;Ponec,M;Hincenbergs,M;Placzek,DR;Elias,PM
培养的人包皮角质形成细胞已被广泛用于研究表皮分化过程中蛋白质含量的调节。在这项研究中，我们考察了它们作为与分化相关的脂质含量和代谢变化的模型系统的有用性。第一代至第三代角质形成细胞在10%胎牛血清中培养在经丝裂霉素处理的3T3饲养层上，并在达到融合之前、期间和之后每隔一段时间收集一次，用于测定脂肪、蛋白质和DNA含量。脂肪合成在融合前培养物中最活跃，并始终与培养物的生长活性密切相关。融合后培养的特征是总脂含量增加，甘油三酯含量和合成增加。脉冲追逐研究表明，甘油三酯POL的标记是不稳定的，并表明即使在融合后的培养中，甘油三酯也为磷脂的生物合成提供了一个脂肪酸储存库。与单烷基二甘油在两种溶剂体系中共迁移的一条新带出现在融合前培养中。在生长的所有阶段，鞘脂在总脂中所占的比例都不到10%，而且只有少量的硫酸胆固醇存在。这些研究阐明了脂肪合成与生长的关系，并表明在标准条件下培养的人包皮角质形成细胞在体内复制不完全的表皮脂肪成分。
Cultured human foreskin keratinocytes have been utilized extensively to study modulations in protein content during epidermal differentiation. In this study we examined their usefulness as a model system for differentiation-linked changes in lipid content and metabolism. First-to-third passage keratinocytes were grown in 10% fetal calf serum on a mitomycin-treated 3T3 feeder layer and harvested at intervals before, during, and after reaching confluence for determination of lipid, protein, and DNA content. Lipid synthesis, determined as acetate incorporation into lipid, was most active in pre-confluent cultures and at all times closely paralleled the growth activity of the cultures. Post-confluent cultures were characterized by an increase in total lipid content and by increased triglyceride content and synthesis. Pulse-chase studies demonstrated that labeling of the triglyceride pol was labile and suggested that even in post-confluent cultures, triglyceride provide a fatty acid reservoir for phospholipid biosynthesis. A novel band, which co-migrated with monoalkyldiacylglycerol in tow solvents systems was in pre-confluent cultures. Sphingolipids constituted less than 10% of total lipid at all stages of growth, and cholesterol sulfate was present only in small quantities. These studies illustrate the relationship of lipid synthesis to growth and demonstrate that human foreskin keratinocytes, cultured under standard conditions, reproduce incompletely the lipid composition of epidermis in vivo.