Scott R E, Maercklein P B
Lab Invest. 1977 Oct;37(4):430-6.
The data presented in this paper establish a correlation between the extent of macrophage spreading and the ability of macrophages to shed plasma membrane vesicles following incubation in a membrane vesiculant. Maximal macrophage spreading was observed following incubation in buffers containing Mn2+ or dithiothreitol. Scanning electron microscopy showed that such macrophages have a uniformly flat surface morphology. Exposure of these macrophage monolayers to a vesiculant containing 25 mM formaldehyde-2 mM dithiothreitol induced plasma membrane vesiculation. Scanning electron microscopy further demonstrated that vesicles were formed and released randomly over the cell surface and that vesicles varied in size from 1 to 15 micrometer. diameter. A variety of chemicals that share the common ability to bind to free sulfhydryl groups have been shown to act as membrane vesiculants as a result of their apparent ability to induce a unique form of cell injury which results in the shedding of cell surface vesicles. The differential effect of vesiculants on cells grown in suspension and as monolayer is interpreted to suggest that reorganization of the cellular cytoskeleton associated with cell spreading may underlie the ability of membrane vesiculants to induce plasma membrane vesiculation in highly spread and adherent macrophage monolayers.
本文所呈现的数据证实了巨噬细胞铺展程度与巨噬细胞在膜泡化剂中孵育后释放质膜囊泡能力之间的相关性。在含有Mn2+或二硫苏糖醇的缓冲液中孵育后，观察到巨噬细胞的最大铺展。扫描电子显微镜显示，此类巨噬细胞具有均匀平坦的表面形态。将这些巨噬细胞单层暴露于含有25 mM甲醛 - 2 mM二硫苏糖醇的泡化剂中会诱导质膜泡化。扫描电子显微镜进一步证明，囊泡在细胞表面随机形成并释放，且囊泡大小从1到15微米不等。直径。由于多种具有结合游离巯基共同能力的化学物质具有诱导独特形式细胞损伤的明显能力，这种损伤会导致细胞表面囊泡脱落，因此它们已被证明可作为膜泡化剂。泡化剂对悬浮生长细胞和单层生长细胞的不同作用被解释为表明，与细胞铺展相关的细胞骨架重组可能是膜泡化剂在高度铺展和贴壁的巨噬细胞单层中诱导质膜泡化能力的基础。
