Weiss L, Poste G, MacKearnin A, Willett K
J Cell Biol. 1975 Jan;64(1):135-45. doi: 10.1083/jcb.64.1.135.
Mammalian and avian cells cultured on glass or plastic substrates produce microexudates of cellular macromolecules which remain bound to the substrate when the cells are detached. The gross macromolecular composition of microexudates from a range of diploid, heteroploid, and virus-transformed cells was determined with cells labeled with radioisotopes. Significant differences in the amounts of cellular glycoproteins, proteins, and RNA present in microexudates were found between different cell types and between cells of the same type at different stages of growth. Inoculation of cells onto substrates "coated" with microexudates altered their growth behavior. Microexudates from exponentially growing subconfluent homotypic and heterotypic cell populations enhanced the growth of mouse and chick embryo cells seeded at very low densities, but similar microexudates had no effect on the proliferation of cells seeded at higher densities. The enhanced growth of low-density cell populations seeded on microexudates was compared with the growth enhancement produced by feeder cell layers and conditioned medium.
在玻璃或塑料基质上培养的哺乳动物和鸟类细胞会产生细胞大分子的微分泌物，当细胞脱离时，这些微分泌物会附着在基质上。用放射性同位素标记细胞，测定了一系列二倍体、异倍体和病毒转化细胞微分泌物的总体大分子组成。在不同细胞类型之间以及同一类型细胞在不同生长阶段的微分泌物中，发现细胞糖蛋白、蛋白质和RNA的含量存在显著差异。将细胞接种到用微分泌物“包被”的基质上会改变其生长行为。指数生长的亚汇合同型和异型细胞群体的微分泌物促进了以非常低密度接种的小鼠和鸡胚细胞的生长，但类似的微分泌物对以较高密度接种的细胞增殖没有影响。将接种在微分泌物上的低密度细胞群体的生长增强与饲养细胞层和条件培养基产生的生长增强进行了比较。
