体外长期培养细粒棘球蚴原头蚴生长发育规律的研究

Study on the growth and development of long-term culture of Echinococcus granulosus protoscolex in vitro

目的探讨总结体外连续培养细粒棘球蚴原头蚴生长发育的规律。方法在5%CO2培养箱中37℃条件下,以RPMI-1640为基础培养基含20%胎牛血清的单相培养体系中体外培养原头蚴,在倒置显微镜下定期动态观察原头蚴的体积及形态学变化,计算其成囊率、蒂端发泡形成率等指标随时间变化情况,总结其体外培养生长发育规律。结果体外培养原头蚴在第1周开始形成蒂端发泡,在体外培养的前6周,原头蚴的形态学以蒂端发泡为主要变化特征,其数量逐渐增加,体积逐渐增大。第5周可观察到原头蚴外周形成一层角质层,开始向成囊方向发育;原头蚴的体积随培养时间的延长逐渐增大,观察到最大囊的直径约为:1.2mm,在体外培养的第17周部分原头蚴囊外周的角质层开始变得毛糙,囊的体积缩小,其内部结构变得模糊不清,浓缩聚集成团,与外周的角质层有明显的界限,培养至7个月时,90%以上的囊泡出现上述形态学改变;原头蚴的最大成囊率约为11%。结论1、体外培养原头蚴的体积随培养时间的延长存在从小到大再逐渐缩小的规律;2、体外培养原头蚴在成囊发育过程中可出现多种不同的形态学变化,是否存在多种成囊方式还需要进一步验证。

Objective The experiment was conducted to investigate the regularity of the growth and development of the Echinococcus granulosus protoscolex cultured in vitro and explore in vitro cultivation of Echinococcus cyst. Methods The Echinococcus granulosus protoscoleces were cultured in the single-phase system in a CO2 incubator at 37 degrees centigrade,and the morphological changes and their volume were regularly observed under the microscope,calculating the rate of encystations and the formation rate of the vesicle at pedicle end of protoscolex cultured in vitro over time,summarize the regularity of the growth and development of the protoscolex cultured in vitro. Results During the first 6 weeks of culture in vitro,the morphological features of protoscoleces were forming the vesicle at pedicle end.When cultivated for 7 days in vitro,they started to form the vesicle at pedicle end and the number is gradually increasing with the extension of the cultivation time.When cultivated for 5 weeks in vitro,they started to develop to cysts and the volume of protoscoleces gradually increased with the extension of culture time.The sizes of largest cyst could reach 1.2 mm.At the 17th week of in vitro culture,the cyst gradually went to aging and died.The rate of encystations was 11%. Conclusion Through the experiment we conclude that the volume of Echinococcus cyst cultured in vitro grows from small to large and then gradually shrinks with the prolongation of culture time and the development of the cyst has an important role in its long-term survival.Whether existed multiple ways of encystation still require further verification.