Ultrastructure of cultured cells from Schistosoma japonicum
Ultrastructure of cultured cells from Schistosoma japonicum
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DOI：
10.1016/s0001-706x(02)00014-1
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发表时间：
2002-05-01
期刊：
影响因子：
2.7
通讯作者：
Jiang, MS
中科院分区：
文献类型：
--
作者：
Dong, HF;Chen, XB;Jiang, MS
本实验观察了日本血吸虫体外培养细胞的超微结构及其动态变化。在培养物中发现多种类型的细胞，包括多边形，圆形颗粒，三角扇形和鞭毛状细胞。成体S.日本血吸虫童虫细胞以圆形颗粒细胞为主。成虫和童虫的细胞表面超微结构不同。成体细胞表面可见乳头状突起、微绒毛和吞饮小泡，而童虫细胞表面未见。但在成体和童虫培养细胞的胞质中均观察到或多或少的线粒体、内质网、核糖体和糖原。细胞核呈圆形，内部有圆形核仁，单位膜上有清晰的孔。在核膜附近有大量块状异染色质。来自不同蠕虫组织的细胞有自己的细胞器。成虫培养物中可观察到生殖细胞、卵黄细胞、火焰细胞、多核被膜下细胞和神经细胞。其中卵黄细胞最多，神经细胞最少。同样，在培养物中也有生殖细胞、支持细胞、火焰细胞、神经细胞、肥大细胞、肌肉细胞、多核被膜下细胞、间质细胞和穿透腺细胞。此外，还发现有少量分裂细胞，表明在体外培养中，胚泡细胞比成体细胞具有更强的增殖潜能。沿着培养时间的延长，染色体细胞的变性越来越严重。一般情况下，培养物的电子密度逐渐降低，线粒体嵴模糊消失，线粒体本身肿胀，最后完全空泡化。在所有培养物中，卵黄细胞对体外条件的变化最为敏感。其变性表现为：（1）卵黄球相互融合，卵黄球与周围膜的间隙逐渐变宽，卵黄球脱落，露出;（2）粗面内质网扩大，空泡化，核糖体脱落;（3）脂质增多，体积增大。大多数胚泡培养物的超微结构变化有以下趋势：（1）异染色质逐渐增多，常染色质逐渐减少;（2）内质网变为短管和空泡，最后消失。从S.超微结构观察发现，日本血吸虫病细胞内线粒体、卵黄球、染色质和内质网均发生了坏死。上述结构的变化可以用来判断培养条件是否合适。(C)2002 Elsevier Science B. V.保留所有权利。
Ultrastructures and their dynamic changes of the cultured cells from Schistosoma japonicum were observed in the present experiments. Several types-including polygonal, round granular, deltaic fan-shaped and flagellated cells-were found in the cultures. The polygonal cells took a major ratio in the cultures from adult S. japonicum, while the majority from schistosomula was round granular cells. The ultrastuctures on the cell surface were different between the cells from adults and schistosomula. Some papilla-like tubercula, microvilli and pinocytotic vesicles were observed on the surface of adult cells, but none were found on schistosomula cells. However, more or less mitochondria, endoplasmic reticula, ribosomes and glycogen were observed in the cytoplasm of the cultured cells from both adults and schistosomula. Golgi complexes were rarely found. The nucleus was round, with round nucleolus inside and clear pores on the unit membrane. There was much lumpish heterochromatin located near to the nuclear membrane. Cells from different worm tissues had their own organelles. The germ cells, vitelline cells, flame cells, multinucleate subtegumental cells and nerve cells could be observed in the cultures from adults. The vitelline cells were the greatest in number and nerve cells were the least in number among them. Similarly, there were germ cells, sustentacular cells, flame cells, nerve cells, mast cells, muscle cells, multinucleate subtegumental cells, interstitial cells and penetration gland cells in the cultures from the schistomomula. In addition, a few division cells were also found. It indicated that the schistosomula cells had greater potential ability to proliferate than the adult cells in in vitro culture. Along with the prolongation of the culture time, degeneration of schistosomal cell occurred more and more. Generally, the electron density of cultures gradually got lower, the cristae of mitochondria blurred and disappeared and the mitochondria themselves swelled and finally vacuoled completely. Vitelline cells were most sensitive to the changes of the in vitro condition in all cultures. Their degeneration showed the following characteristics: (1) vitelline globules fused each other, the space between vitelline globules and the membrane surrounding them broadened gradually and vitelline globules were released and uncovered; (2) rough-surfaced endoplasmic reticula enlarged, vacuolated and the ribosomes dropped; and (3) the number and volume of lipid increased. The ultrastructural changes of most of the cultures from schistosomula had the following trends: (1) heterochromatin increased and euchromatin decreased gradually; and (2) endoplasmic reticula changed into short tubes and vacuoles and disappeared finally. The degenerative process of the cultures from S. japonicum consisted of necrosis according to the ultrastructural changes of the mitochondria, vitelline globules, chromatin and endoplasmic reticula within the cells. The changes of the above structures could be used to estimate whether the culture conditions were appropriate. (C) 2002 Elsevier Science B.V. All rights reserved.