Coustau C, Ataev G, Jourdane J, Yoshino T P
Centre de Biologie et d'Ecologie Tropicale et Méditerranéenne, UMR 5555 du CNRS, Université de Perpignan, France.
Exp Parasitol. 1997 Oct;87(2):77-87. doi: 10.1006/expr.1997.4184.
In vitro cultivation of Schistosoma japonicum miracidia to the mother sporocyst (MS) and then to the daughter sporocyst (DS) stage was achieved using the Biomphalaria glabrata embryonic (Bge) cell line as a coculture system. When comparing the effect of Bge cell and MS density on MS development, it was apparent that Bge cell density had a highly significant effect on both MS viability and growth. Viability and growth rate of MS cultured under high cell density conditions (350 cells/mm2) were almost 2 times greater than those of MS cultured under conditions of low cell density (60 cells/mm2). Growth under high cell density conditions corresponded to a 20 to 30 times increase in MS estimated volume within the first 9 weeks of cultivation. Emergence of fully formed motile DS was first observed after 11 weeks of cocultivation. A few DS lived for 14 weeks after emergence and attained a size of 770 +/- 100 microns in length and 48 +/- 13 microns in width. In contrast to what was observed in Bge cell/Schistosoma mansoni cocultures, Bge cells did not encapsulate S. japonicum MS. Our results show that, although the cellular interactions between Bge cells and schistosomes MS display some level of specificity, Bge cells apparently secrete soluble factors that permit excellent survival and can trigger advanced in vitro development of S. japonicum.
利用光滑双脐螺胚胎（Bge）细胞系作为共培养系统，实现了日本血吸虫毛蚴在体外培养至母胞蚴（MS）阶段，进而培养至子胞蚴（DS）阶段。在比较Bge细胞密度和MS密度对MS发育的影响时，很明显Bge细胞密度对MS的活力和生长均有极显著影响。在高细胞密度条件（350个细胞/mm²）下培养的MS的活力和生长速率几乎是在低细胞密度条件（60个细胞/mm²）下培养的MS的2倍。在高细胞密度条件下生长，在培养的前9周内MS估计体积增加了20至30倍。共培养11周后首次观察到完全形成的可运动的DS出现。一些DS在出现后存活了14周，长度达到770±100微米，宽度达到48±13微米。与在Bge细胞/曼氏血吸虫共培养中观察到的情况不同，Bge细胞不会包裹日本血吸虫MS。我们的结果表明，尽管Bge细胞与血吸虫MS之间的细胞相互作用表现出一定程度的特异性，但Bge细胞显然分泌了可溶性因子，这些因子能使日本血吸虫在体外具有良好的存活率，并能触发其进一步发育。
