模型寄生虫物种,其整个生命周期可以在实验室中完成并维持多代,在我们对宿主-寄生虫相互作用的理解中发挥了重要作用。然而,将寄生虫保持在实验室条件下可能会使它们暴露在不自然的进化压力下,因此,使用实验室培养物进行研究并非没有限制。使用2种广泛使用的模型蠕虫物种,短尾线虫和多回线虫,我说明了在解释模型物种的实验结果时需要谨慎。我首先回顾了过去40年中发表的关于这些物种的1200多项实验研究,以确定他们为哪些研究领域做出了贡献。接下来是对提供这些研究中使用的寄生虫的机构实验室培养物的检查。其中一些已经持续了几十年,在已发表的研究中占了很大比例,而其他人则是短暂的。利用活跃文化策展人提供的信息,我总结了它们的起源和维护条件的数据。最后,我讨论了实验室培养物如何受到进化遗传过程的影响,比如创始人的影响,遗传漂变和近亲繁殖。我还谈到了这样一种可能性,即通过多代实验室宿主的连续传代对几种寄生虫性状进行了人工选择,导致实验室培养之间的遗传和表型差异,在这些文化和天然寄生虫种群之间。最后,我建议继续使用实验室蠕虫培养物,以最大程度地发挥其对寄生虫学研究的重要贡献。
Model parasite species, whose entire life cycle can be completed in the laboratory and maintained for multiple generations, have played a fundamental role in our understanding of host–parasite interactions. Yet, keeping parasites in laboratory conditions may expose them to unnatural evolutionary pressures, and using laboratory cultures for research is therefore not without limitations. Using 2 widely-used model helminth species, the cestode Hymenolepis diminuta and the nematode Heligmosomoides polygyrus, I illustrate the caution needed when interpreting experimental results on model species. I first review more than 1200 experimental studies published on these species in the past 4 decades, to determine which research areas they have contributed to. This is followed by an examination of the institutional laboratory cultures that have provided the parasites used in these studies. Some of these have persisted for decades and accounted for a substantial proportion of published studies, whereas others have been short-lived. Using information provided by the curators of active cultures, I summarize data on their origins and maintenance conditions. Finally, I discuss how laboratory cultures may have been subject to the influence of evolutionary genetic processes, such as founder effects, genetic drift and inbreeding. I also address the possibility that serial passage through laboratory hosts across multiple generations has exerted artificial selection on several parasite traits, resulting in genetic and phenotypic divergence among laboratory cultures, and between these cultures and natural parasite populations. I conclude with recommendations for the continued usage of laboratory helminth cultures aimed at maximizing their important contribution to parasitological research.