Willett Sophie, Olson Sonja A, Horejsi Rachel V, Nelson Chase N, Wheeler Nicolas J
Department of Biology, University of Wisconsin-Eau Claire, Eau Claire, WI.
bioRxiv. 2025 Aug 19:2025.08.15.670345. doi: 10.1101/2025.08.15.670345.
Schistosomiasis is a neglected tropical disease caused by human-infective schistosomes (Trematoda: ). Intestinal schistosomiasis in sub-Saharan Africa and the Neotropics is caused primarily by and is transmitted by several planorbid snail species. Adult male and female parasites in the definitive mammalian host pair and reside in the mesenteric vasculature; females lay eggs that traverse the intestinal wall to be excreted, but a significant proportion become trapped in host tissues, especially the liver, eliciting granulomatous immune responses that underlie most disease pathology. is the primary lab model for research and, due to the abundance and ease of harvesting, liver-derived eggs are almost exclusively used to maintain the life cycle and to study miracidia and subsequent larval stages. However, recent evidence shows that eggs from the liver or intestine have key morphometric, transcriptomic, and antigenic differences, which can profoundly affect experimental outcomes. To determine whether these differences extend to the miracidia stage, we compared miracidia hatched from mouse liver and intestine-derived eggs, sequencing their transcriptomes and assessing their unstimulated behaviors over time in an arena allowing for high-resolution tracking of miracidia behavior at a large spatiotemporal scale. We found that while transcriptomic profiles of miracidia are distinguishable based on egg tissue origin, only a small subset of genes is differentially expressed. Further, basic, unstimulated behavior of miracidia that developed in different niches of the definitive host was significantly different. These different behavioral programs may reflect intrinsic developmental programming or differential viability and hardiness related to tissue origin. These findings underscore the importance of egg source in experimental design and interpretation, with significant implications for the maintenance of laboratory life cycles and the use of miracidia in schistosomiasis research.
血吸虫病是一种由感染人类的血吸虫（吸虫纲：）引起的被忽视的热带疾病。撒哈拉以南非洲和新热带地区的肠道血吸虫病主要由引起，通过几种扁卷螺传播。在终末哺乳动物宿主中，成年雌雄寄生虫配对并寄居于肠系膜血管；雌虫产卵，卵穿过肠壁排出，但很大一部分会被困在宿主组织中，尤其是肝脏，引发肉芽肿性免疫反应，这是大多数疾病病理的基础。是研究的主要实验室模型，由于数量丰富且易于采集，几乎仅使用源自肝脏的卵来维持生命周期并研究毛蚴及后续幼虫阶段。然而，最近的证据表明，来自肝脏或肠道的卵在形态测量、转录组和抗原方面存在关键差异，这可能会深刻影响实验结果。为了确定这些差异是否延伸到毛蚴阶段，我们比较了从小鼠肝脏和肠道来源的卵孵化出的毛蚴，对它们的转录组进行测序，并在一个允许在大时空尺度上对毛蚴行为进行高分辨率跟踪的实验场中评估它们随时间的未受刺激行为。我们发现，虽然毛蚴的转录组谱可根据卵的组织来源区分，但只有一小部分基因差异表达。此外，在终末宿主不同生态位发育的毛蚴的基本未受刺激行为存在显著差异。这些不同的行为程序可能反映了内在的发育编程或与组织来源相关的不同活力和抗性。这些发现强调了卵源在实验设计和解释中的重要性，对维持实验室生命周期以及在血吸虫病研究中使用毛蚴具有重大意义。
