土壤微塑料(MPs)被蚯蚓摄食后会造成肠道损伤，并伴随着肠道菌群的失调。但MPs在肠道内的靶点和作用机制尚不清楚。肠道菌群对肠黏膜屏障功能的调节十分重要。Toll样受体(TLRs) 则是肠道菌群维持肠黏膜结构完整和免疫功能稳定的重要介导者。那么，MPs诱发蚯蚓肠道菌群失调是否导致肠道TLRs表达模式发生变化，从而引起肠道通透性改变以及下游免疫效应分子抗菌肽(AMPs)表达变化，进而影响肠黏膜屏障功能？本研究拟通过体内和体外实验研究土壤MPs暴露引起的蚯蚓肠道菌群结构、TLRs和AMPs等天然免疫相关基因表达的变化，以及这些变化与肠黏膜屏障功能的关系；从肠道菌群—TLRs—AMPs途径研究MPs对蚯蚓肠黏膜屏障功能的影响和可能的调控机制。本研究有望发现用于评价MPs致肠道屏障功能损伤的新生物标记物，并为以肠道菌群为靶向的土壤MPs生态危害防控研究奠定基础。

Soil microplastic (MPs) ingestion by earthworms will lead to intestinal injury, and gut microbiota imbalance. The targets and toxicological mechanism of MPs contribute to intestinal injury is still unclear. The intestinal microbiome plays a critical role in regulating the intestinal barrier function. Toll-like receptors (TLRs) are important mediators of gut microbiota to maintain the integrity of intestinal mucosa and balance mucosal immunity. Then, does MPs-induced disordered gut microbiota of earthworm lead to changes in the expression pattern of TLRs, that could result in the alteration of intestinal permeability and expression of downstream immune effector molecules (such as antimicrobial peptides, AMPs), which in turn affects intestinal mucosal barrier function? Both in vitro and in vivo experiments are used to study the changes in the structure of earthworm gut microbiota, the expression of TLRs, antimicrobial peptides and other natural immune-related genes after soil MPs exposure. Further, the relationship between these changes and the intestinal mucosal barrier function will be investigated. From a gut microbiota—TLRs—antimicrobial peptide pathway perspective, we study the effects of MPs on the intestinal mucosa barrier function of the earthworm and possible regulatory mechanisms. This study is expected to find new biomarkers for evaluating intestinal barrier damage caused by MPs and lay a foundation for the prevention and control of ecological hazards of soil MPs targeting the gut microbiota.