豆状囊尾蚴小胞外囊泡可抑制家兔外周血淋巴细胞NLRP3活化

Small extracellular vesicles from Cysticercus pisiformis can downregulate the activation of NLRP3 in peripheral blood lymphocytes

本研究旨在探究家兔感染豆状囊尾蚴过程中炎症小体的表达。取豆状带绦虫的孕卵节片感染家兔,分离不同感染时期的外周血淋巴细胞(PBLC),检测NLRP3、IL-1β等炎症小体相关基因的表达水平。同时,收集豆状囊尾蚴的分泌排泄产物(ESP),并通过超速离心分离小胞外囊泡,用ESP和小胞外囊泡分别处理PBLC,24小时后,利用qPCR和Western-blot分析炎症小体相关基因的表达变化。结果显示,家兔感染后第30天和60天,炎症小体相关基因NLRP3、IL-1β、Caspase-1及GSDMD的表达水平明显升高,而在感染第90天时明显下降;用ESP处理PBLC后,NLRP3、IL-1β、Caspase-1及GSDMD的表达水平也明显升高;而用小胞外囊泡处理细胞后,虽然IL-1β的表达水平升高,但NLRP3、Caspase-1及GSDMD的表达水平明显受到了抑制。说明豆状囊尾蚴可通过其ESP或小胞外囊泡调控家兔PBLC炎症小体的活化,从而达到其长期生存和持续感染的目的。

The aim of the study is to explore the expression of inflammasome during Cysticercus pisiformis infection.The eggs in gravid proglottids of Taenia pisiformis were collected and then used to infect rabbits.Primary peripheral blood lymphocytes(PBLC)at different times post infection with C.pisiformis were isolated and inflammasome related genes such as NLRP3 and IL-1βwere detected.Besides,excretory-secretory products(EsP)and small extracellular vesicles(sEv)collected from C.pisiformis were used to treat PBLC and inflammasome related genes were detected using qPCR and Western-blot after 24h.The results showed that the expression of NLRP3,IL-1β,Caspase-1 and GSDMD were significantly up-regulated at 30 days and 60 days post infection of C.pisiformis,and were down-regulated at 90 days.The expression of NLRP3,IL-1β,Caspase-land GSDMD were significantly up-regulated in PBLC treated with ESP of C.pisiformis.The expression of IL-1βwas significantly up-regulated after treating with sEV,but the expression of NLRP3,Caspase-1,IL-18 and GSDMD were inhibited.These results demonstrated that ESP and small extracellular vesicles can regulate the activation of inflammasome during C.pisiformis infection,which may obtain a long-term survival and persistent infection of parasites.