Immune factors in snails of the genus Biomphalaria are critical for combating Schistosoma mansoni, the predominant cause of human intestinal schistosomiasis. Independently, many of these factors play an important role in, but do not fully define, the compatibility between the model snail B. glabrata, and S. mansoni. Here, we demonstrate association between four previously characterized humoral immune molecules; BgFREP3, BgTEP1, BgFREP2 and Biomphalysin. We also identify unique immune determinants in the plasma of S. mansoni-resistant B. glabrata that associate with the incompatible phenotype. These factors coordinate to initiate haemocyte-mediated destruction of S. mansoni sporocysts via production of reactive oxygen species. The inclusion of BgFREP2 in a BgFREP3-initiated complex that also includes BgTEP1 almost completely explains resistance to S. mansoni in this model. Our study unifies many independent lines of investigation to provide a more comprehensive understanding of the snail immune system in the context of infection by this important human parasite.

中文翻译：

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体液免疫因子的协调决定了曼氏血吸虫和光滑小球藻之间的相容性

Biomphalaria蜗牛中的免疫因子对于抵抗曼氏血吸虫（人类肠道血吸虫病的主要原因）至关重要。独立地，这些因素中的许多因素在模型蜗牛B. glabrata和S. mansoni之间的兼容性中起着重要作用，但并未完全定义。在这里，我们证明了四个先前表征的体液免疫分子之间的关联。Bg FREP3，Bg TEP1，Bg FREP2和生物膜溶素。我们还鉴定了曼氏沙门氏菌耐药的光滑布拉氏梭菌血浆中的独特免疫决定因子。与不兼容表型相关联。这些因子通过产生活性氧来协调启动血红细胞介导的曼氏沙门氏菌孢子囊破坏。列入博伽FREP2在博伽FREP3发起的复杂，也包括博伽TEP1几乎完全解释对性曼氏血吸虫在这个模型中。我们的研究统一了许多独立的研究方向，以便在这种重要的人类寄生虫感染的情况下提供对蜗牛免疫系统的更全面的了解。