Membrane knobs of unfixed Plasmodium falciparum infected erythrocytes: New findings as revealed by atomic force microscopy and surface potential spectroscopy
Membrane knobs of unfixed Plasmodium falciparum infected erythrocytes: New findings as revealed by atomic force microscopy and surface potential spectroscopy
复制标题
DOI：
10.1006/expr.1996.0122
复制
发表时间：
1996-12-01
影响因子：
2.1
通讯作者：
Tandler, B
中科院分区：
文献类型：
--
作者：
Aikawa, M;Kamanura, K;Tandler, B
脑型疟疾是疟疾的一种严重并发症，由恶性疟原虫感染的红细胞阻塞脑微血管引起。这些细胞通过寄生虫在红细胞膜上诱导的“旋钮"粘附到内皮细胞上。当原子力显微镜被用来研究未固定的感染红细胞的旋钮的结构，每个旋钮被发现由两个不同的亚基，旋钮组件，从来没有见过在化学固定旋钮检查传统的透射电子显微镜。表面电位光谱显示，旋钮具有正电荷（+20 mV），而红细胞质膜的其余部分带负电荷。由于内皮细胞质膜具有负电荷，因此旋钮和内皮细胞之间的电荷差异可能在两种细胞类型之间的细胞粘附中起重要作用。球的亚单位结构可能是排列粘附分子的空间必需品，以便它们能够发挥作用。这项研究表明，原子力显微镜具有很大的潜力，在其自然状态下的细胞检查;结合表面电位光谱，它可以揭示细胞功能的基本过程和机制。(C)出版社：Academic Press，Inc.
Cerebral malaria, a severe complication of malaria, is caused by the obstruction of cerebral microvessels by Plasmodium falciparum-infected erythrocytes. Such cells adhere to endothelial cells by means of ''knobs'' induced on the red cell membrane by the parasites. When atomic force microscopy was used to investigate the structure of the knobs of unfixed infected red cells, each knob was found to consist of two distinct subunits, knob components that have never been seen in chemically fixed knobs examined by conventional transmission electron microscopy. Surface potential spectroscopy revealed that the knobs have a positive charge (+20 mV), whereas the remainder of the red cell plasma membrane is negatively charged. Since endothelial plasma membranes have a negative charge, the charge difference between knobs and endothelium may play a significant role in cytoadherence between the two cell types. The subunit structure of the knobs may be a steric necessity to align adherence molecules so that they can exert their effect. This study shows that the atomic force microscope has great potential for examination of cells in their native state; in combination with surface potential spectroscopy, it may uncover fundamental processes and mechanisms in cell function. (C) 1996 Academic Press, Inc.