MCF—7细胞在亚多层中细胞膜极性的变化

Sub-multilayer of MCF-7 cell, an established human breast carcinoma cell line, was achieved by culturing the cells on millipore filters for a long time. The superficial layer cells maintained their membrane polarity features as MCF-7 cells in monolayers did. MAM-6, a human milk fat globule membrane antigen, was polarized distributed in apical domain of 97.5% superficial layer cells revealed by immunoperoxidase cytochemistry. Whereas, among the low layer cells, which had no free surface (apical domain) toward the culture medium and did not show morphological polarity features, only 12.9% expressed surface MAM-6 with weak immunoperoxidase staining and random distribution. But the immunostaining for detecting cytoplasmic MAM-6 in low layer cells was stronger than that in superficial layer cells, indicating that the vectorial delivery and insert of MAM-6 carrying glycoprotein to the plasma membrane seemed to be stopped or declined and became undirectional in the later situation. The study demonstrates that an asymmetric spatial environment, which is composed of a liquid phase space and a solid phase space, is crucial for the establishment of epithelial membrane polarity of MCF-7 cells.     

皮肤创伤愈合中几种生长因子的免疫组织化学研究

用免疫荧光ABC法动态观察了大鼠皮肤创伤愈合过程中转化生长因子β（TGFβ1、β2、β3）·表皮生长因子（EGF）和白介素-6（IL－6）的分布。背部创伤术后1天,创面血痂中五种生长因子免疫染色均呈阳性。术后3天与7天,肉芽组织中密集的成纤维细胞内除TGFβ3、外其余四种生长因子呈阳性,巨噬细胞呈TGFβ1、TGFβ2与IL－6阳性。术后14天与28天,组织内细胞密度降低而其免疫染色性质不变。本文讨论了这些生长因子与创伤愈合的关系。     

氯化镨在小鼠肝脏细胞中形成含镨致密体

本实验给小鼠4次注射氯化镨(总剂量为200mg/kg)后,光镜发现肝细胞呈嗜酸变性或空泡变性,肝细胞与枯否细胞中酸性磷性酶阳性的溶酶体增多。电镜观察到肝细胞出现程度不同的核变形、内质网扩张、糖原缺乏、溶酶体含较多高电子密度微粒。肝细胞与枯否细胞中均出现由高电子密度微粒聚集形成的致密体,应用X射线微区分析术可测到镨特征性能谱峰。     

钐在小鼠肝脏细胞中的动态观察

It is generally considered that the rare earth compounds are plasma membrane-impermeable, thus affecting the cells only on their surface. Recently, we found that after repeated injections to mice of large dose of samarium trichloride, a soluble compound of rare earth, samarium aggregates appeared in Kupffer cells and hepatocytes of liver. In this study, we aimed at observing the route by which samarium enters the liver cells and the process of the formation of samarium aggregates. Samarium trichloride was given to Swiss mice at one dose of 70 mg/kg intravenously. Thereafter, at different intervals from 15 min to 48 h after the injection, the samarium in liver was traced dynamically by electron microscopy and X ray microanalysis. From 15 min to 2 h both Kupffer cells and hepatocytes endocytosed samarium-containing particles and formed phagosomes, in which the ingested particles were progressively concentrated. Besides, the small phagosomes fused with each other. Phagocytosis was especially active in Kupffer cells. During the 4 h to 24 h many Kupffer cells were degenerated and broken. In hepatocytes the phagosomes gathered mostly around the bile canaliculi. Groups of highly electron-dense particles were found in the lumen of bile canaliculi, implying the excretion of samarium by bile. At the 48 h, the samarium-containing phagosomies were found still in both kinds of cells in the liver.     

微原纤维

微原纤维有Ⅵ型胶原蛋白微原纤维和原纤维蛋白微原纤维二种。前者广泛存在于固有结缔组织中,确切功能尚不清楚。原纤维蛋白微原纤维由原纤维蛋白、微原纤维相关蛋白、潜在转化生长因子β结合蛋白等成分构成,主要作为弹性纤维的组成部分,并参与弹性纤维的形成,其次是单独地分布于器官的细胞外基质中,提供一种柔韧性的连接方式。原纤维蛋白的基因突变可引发马凡综合征及相关的微原纤维病。     

钐在小鼠肝脏细胞中的动态观察

本实验给小鼠一次静脉注射氯化钐(70mg/kg体重)后15min至48h中的不同间期,应用电镜与X射线微区分析术对钐在肝脏枯否细胞与肝细胞中的运转进行了动态追踪。于15min 至2 h,两种细胞均以胞吞方式摄入含钐微粒,在胞质中形成吞噬体。在吞噬体中,微粒群处于由稀疏至密集的浓缩过程。小吞噬体亦互相融合。这种胞吞作用于枯否细胞极为活跃。于4—24 h,很多枯否细胞胞质充满吞噬体,细胞已经或趋于变性、崩解。肝细胞内的吞噬体则汇集于胆小管周围。于胆小管腔中可见到高电子密度微粒群,表明体内钐可经胆汁途径排出。于48 h,两种肝脏细胞巾仍见钐吞噬体沉积。     

稀土元素铈铕钆铽在小鼠肝脏中的分布与沉积的电镜与X射线微区分析术研究

本实验分别给小鼠腹腔与静脉隔日交替注射稀土元素化合物氯化铈、氯化铕、硝酸钆、葡萄糖酸铽,共五次,总剂量为300～630mg/kg。电镜观察显示,四种元素均于枯否细胞和肝细胞中形成凝集体,枯否细胞中尤多。应用X射线微区分析术于凝集体分别探测到四种稀土元素的特征性X射线能谱峰。两种细胞的溶酶体内含较多高电子密度微粒。于胆小管腔亦发现高电子密度微粒群,提示肝细胞中的稀土元素可随胆汁排出。本文描述了四种稀土元素引起的肝脏形态学变化。     

MCF-7细胞在亚多层中细胞膜极性的变化

人乳腺癌细胞株MCF-7细胞于微孔滤膜上经较长时间培养后形成亚多层。表层细胞保持了单层MCF-7细胞所具有的形态学极性与膜极性特征。免疫酶细胞化学技术显示,97.5%的细胞表达了表面乳脂球膜抗原MAM-6,并且该抗原呈顶面极性分布。深层细胞没有面向培养液的游离面,缺乏形态学极性特征,仅??12.9%的细胞表达表面MAM-6,且呈无极性随机分布。深层细胞胞质的MAM-6免疫染色强度大于表层细胞。本研究结果提示,非对称性空间环境(由液相空间与固相空间构成)对于MCF-7细胞的膜极性的建立是必需的。