Balantioides coli is a known ciliated zoonotic protozoan that mainly causes diarrhea in humans and pigs. An efficient and reliable culture system for this parasite remains unavailable until now. In this study, a modified Dulbecco's modified eagle medium (DMEM) with pH 7.0–7.5, containing 5 mg/mL starch and 20% new calf serum, was optimized for propagation of B. coli at 28°C–32°C. At the growth-peaking stage, the average trophozoite density was up to 12,970 trophozoites per milliliter. A reproducible protocol for isolation and maintenance of this parasite was also developed based on the modified DMEM culture medium. Moreover, cloning results of B. colipopulations showed that 250 trophozoites in 3 mL modified DMEM medium were the minimal number of trophozoites that propagated to the growth-peaking stage, and finally obtained the individual population. However, less than 250 trophozoites failed to continuously grow in the modified DMEM culture medium under the optimal conditions for growth of B. coli. These data showed that the modified DMEM culture medium is an ideal and efficient medium for propagation and maintenance of B. coli in vitro and will help studies on its biology, genome, transcriptome, proteome, and drug screening.

Balantioides coli是一种已知的有纤毛的人畜共患的原生动物，主要引起人和猪的腹泻。迄今为止，仍没有有效，可靠的寄生虫培养系统。在这项研究中，改良的Dulbecco改良的Eagle培养基（DMEM）的pH值为7.0-7.5，其中含有5 mg / mL的淀粉和20％的新牛犊血清，针对在28°C至32°C的细菌繁殖进行了优化。在生长高峰期，滋养体的平均密度达到每毫升12970个滋养体。基于修饰的DMEM培养基，还开发了用于分离和维持该寄生虫的可再现方案。此外，大肠杆菌的克隆结果种群显示，在3 mL改良DMEM培养基中，250个滋养体是滋养体繁殖到生长高峰期的最小数量，并最终获得了个体。然而，少于250个滋养体未能在B. coli的最佳生长条件下在改良的DMEM培养基中连续生长。这些数据表明，改良的DMEM培养基是在体外繁殖和维持B. coli的理想且有效的培养基，将有助于对其生物学，基因组，转录组，蛋白质组和药物筛选的研究。