Gao Yu, Zhou Min, Zhang Wen, Jiang Jinxing, Ouyang Zhibin, Zhu Yuanfang, Li Ning
Obstetrics and Gynecology, The Second Clinical Medical College (Shenzhen People's Hospital), Jinan University, Shenzhen, China.
Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China.
Ann Transl Med. 2022 Nov;10(22):1202. doi: 10.21037/atm-22-4120.
Intrauterine () infections pose a major threat during pregnancy via affecting placental immune responses. However, the underlying mechanisms of placental defense against this pathogen remain ill-defined. Therefore, this study aims to investigate the function and the mechanism of inflammasomes on against infection during pregnancy.
A listeriosis murine model and cell culture system was used to investigate the role of trophoblastic nucleotide-binding oligomerization domain-like receptor pyrin domain-containing 3 (NLRP3) in orchestrating innate immune responses to infection. Caspase-1 activity was determined using a caspase-1 activity colorimetric kit. NLRP3 and apoptosis-associated speck-like protein containing a CARD (ASC) in placental tissue was detected by immunohistochemistry. NLRP3 in HTR-8/SVneo cells was also detected by immunofluorescence. The expression of interleukin 1β (IL-1β), NLRP3, ASC, and caspase-1 was detected by Western blot. We characterized the NLRP3 inflammasome in trophoblast cells according to whether infection increased the activation of caspase-1 and the release of IL-1β. For human or mouse IL-1β in the culture supernatants and mouse tissue lysates were analyzed using ELISA Kits.
Trophoblast cells constitutively expressed the components of the NLRP3 inflammasome. , triggers NLRP3 inflammasome activation in trophoblast cells by inducing caspase-1 activation, increasing the NLRP3 protein levels, IL-1β maturation and secretion in HTR-8/SVneo cells. , induces fetal resorption and IL-1β processing in pregnant mice. In addition, NLRP3-deficient mice were more prone to fetal loss than their wild-type counterparts following infection with at a lower infective dose.
We conclude that trophoblast cells respond to infection through the NLRP3 receptor, resulting in inflammasome activation and IL-1β production, which prevents listeriosis during pregnancy.
宫内感染通过影响胎盘免疫反应对孕期构成重大威胁。然而，胎盘抵御这种病原体的潜在机制仍不清楚。因此，本研究旨在探讨炎性小体在孕期抵御感染中的功能及机制。
利用李斯特菌病小鼠模型和细胞培养系统，研究滋养层细胞含吡咯结构域的核苷酸结合寡聚化结构域样受体3（NLRP3）在协调对感染的天然免疫反应中的作用。使用caspase-1活性比色试剂盒测定caspase-1活性。通过免疫组化检测胎盘组织中NLRP3和含半胱天冬酶激活和招募结构域的凋亡相关斑点样蛋白（ASC）。通过免疫荧光也检测了HTR-8/SVneo细胞中的NLRP3。通过蛋白质印迹法检测白细胞介素1β（IL-1β）、NLRP3、ASC和caspase-1的表达。根据感染是否增加caspase-1的激活和IL-1β的释放，我们对滋养层细胞中的NLRP3炎性小体进行了表征。对于人或小鼠，使用酶联免疫吸附测定试剂盒分析培养上清液和小鼠组织裂解物中的IL-1β。
滋养层细胞组成性表达NLRP3炎性小体的成分。感染通过诱导caspase-1激活、增加HTR-8/SVneo细胞中NLRP3蛋白水平、IL-1β成熟和分泌，触发滋养层细胞中NLRP3炎性小体激活。感染诱导孕鼠胎儿吸收和IL-1β加工。此外，在较低感染剂量下感染后，NLRP3缺陷小鼠比野生型小鼠更容易发生胎儿丢失。
我们得出结论，滋养层细胞通过NLRP3受体对感染作出反应，导致炎性小体激活和IL-1β产生，从而在孕期预防李斯特菌病。
