Institute of Neuroscience, University of Oregon, Eugene, OR, United States of America.
PLoS One. 2023 Feb 9;18(2):e0280999. doi: 10.1371/journal.pone.0280999. eCollection 2023.
The nematode Caenorhabditis elegans is a model organism widely used in basic, translational, and industrial research. C. elegans development is characterized by five morphologically distinct stages, including four larval stages and the adult stage. Stages differ in a variety of aspects including size, gene expression, physiology, and behavior. Enrichment for a particular developmental stage is often the first step in experimental design. When many hundreds of worms are required, the standard methods of enrichment are to grow a synchronized population of hatchlings for a fixed time, or to sort a mixed population of worms according to size. Current size-sorting methods have higher throughput than synchronization and avoid its use of harsh chemicals. However, these size-sorting methods currently require expensive instrumentation or custom microfluidic devices, both of which are unavailable to the majority C. elegans laboratories. Accordingly, there is a need for inexpensive, accessible sorting strategies. We investigated the use of low-cost, commercially available cell strainers to filter C. elegans by size. We found that the probability of recovery after filtration as a function of body size for cell strainers of three different mesh sizes is well described by logistic functions. Application of these functions to predict filtration outcomes revealed non-ideal properties of filtration of worms by cell strainers that nevertheless enhanced filtration outcomes. Further, we found that serial filtration using a pair of strainers that have different mesh sizes can be used to enrich for particular larval stages with a purity close to that of synchronization, the most widely used enrichment method. Throughput of the cell strainer method, up to 14,000 worms per minute, greatly exceeds that of other enrichment methods. We conclude that size sorting by cell strainers is a useful addition to the array of existing methods for enrichment of particular developmental stages in C. elegans.
秀丽隐杆线虫是一种模式生物，广泛应用于基础研究、转化研究和工业研究。秀丽隐杆线虫的发育特征是五个形态明显不同的阶段，包括四个幼虫阶段和成虫阶段。各阶段在大小、基因表达、生理和行为等方面存在差异。富集特定发育阶段通常是实验设计的第一步。当需要数百条线虫时，标准的富集方法是让孵化后的同步种群生长固定时间，或根据大小对混合种群的线虫进行分选。目前的大小分选方法具有比同步更高的通量，并且避免了其使用苛刻的化学物质。然而，这些大小分选方法目前需要昂贵的仪器或定制的微流控设备，而大多数秀丽隐杆线虫实验室都无法获得这些设备。因此，需要一种廉价、可获得的分选策略。我们研究了使用低成本、市售的细胞筛子按大小对秀丽隐杆线虫进行过滤。我们发现，对于三种不同网眼尺寸的细胞筛子，过滤后回收的概率与身体大小的关系可以很好地用逻辑函数来描述。应用这些函数预测过滤结果表明，细胞筛子过滤线虫存在不理想的特性，但仍能提高过滤效果。此外，我们发现使用具有不同网眼尺寸的一对筛子进行连续过滤可以用于富集特定的幼虫阶段，其纯度接近最广泛使用的富集方法——同步。细胞筛子方法的通量高达每分钟 14,000 条线虫，大大超过了其他富集方法。我们得出结论，细胞筛子大小分选是秀丽隐杆线虫中富集特定发育阶段的现有方法的有益补充。
