PDF(Pubmed)
Abstract：
BACKGROUND: Toxoplasma gondii infection causes adverse pregnancy outcomes by affecting the expression of immunotolerant molecules in decidual immune cells. Galectin-9 (Gal-9) is widely expressed in decidual macrophages (dMφ) and is crucial for maintaining normal pregnancy by interacting with the immunomodulatory protein T-cell immunoglobulin and mucin domain-containing molecule 3 (Tim-3). However, the effects of T. gondii infection on Gal-9 expression in dMφ, and the impact of altered Gal-9 expression levels on the maternal-fetal tolerance function of decidual natural killer (dNK) cells, are still unknown.
METHODS: Pregnancy outcomes of T. gondii-infected C57BL/6 and Lgals9-/- pregnant mice models were recorded. Expression of Gal-9, c-Jun N-terminal kinase (JNK), phosphorylated JNK (p-JNK), and Forkhead box protein O1 (FOXO1) was detected by western blotting, flow cytometry or immunofluorescence. The binding of FOXO1 to the promoter of Lgals9 was determined by chromatin immunoprecipitation-polymerase chain reaction (ChIP-PCR). The expression of extracellular signal-regulated kinase (ERK), phosphorylated ERK (p-ERK), cAMP-response element binding protein (CREB), phosphorylated CREB (p-CREB), T-box expressed in T cells (T-bet), interleukin 10 (IL-10), and interferon gamma (IFN-γ) in dNK cells was assayed by western blotting.
RESULTS: Toxoplasma gondii infection increased the expression of p-JNK and FOXO1 in dMφ, resulting in a reduction in Gal-9 due to the elevated binding of FOXO1 with Lgals9 promoter. Downregulation of Gal-9 enhanced the phosphorylation of ERK, inhibited the expression of p-CREB and IL-10, and promoted the expression of T-bet and IFN-γ in dNK cells. In the mice model, knockout of Lgals9 aggravated adverse pregnancy outcomes caused by T. gondii infection during pregnancy.
CONCLUSIONS: Toxoplasma gondii infection suppressed Gal-9 expression in dMφ by activating the JNK/FOXO1 signaling pathway, and reduction of Gal-9 contributed to dysfunction of dNK via Gal-9/Tim-3 interaction. This study provides new insights for the molecular mechanisms of the adverse pregnancy outcomes caused by T. gondii.
METHODS: Pregnancy outcomes of T. gondii-infected C57BL/6 and Lgals9-/- pregnant mice models were recorded. Expression of Gal-9, c-Jun N-terminal kinase (JNK), phosphorylated JNK (p-JNK), and Forkhead box protein O1 (FOXO1) was detected by western blotting, flow cytometry or immunofluorescence. The binding of FOXO1 to the promoter of Lgals9 was determined by chromatin immunoprecipitation-polymerase chain reaction (ChIP-PCR). The expression of extracellular signal-regulated kinase (ERK), phosphorylated ERK (p-ERK), cAMP-response element binding protein (CREB), phosphorylated CREB (p-CREB), T-box expressed in T cells (T-bet), interleukin 10 (IL-10), and interferon gamma (IFN-γ) in dNK cells was assayed by western blotting.
RESULTS: Toxoplasma gondii infection increased the expression of p-JNK and FOXO1 in dMφ, resulting in a reduction in Gal-9 due to the elevated binding of FOXO1 with Lgals9 promoter. Downregulation of Gal-9 enhanced the phosphorylation of ERK, inhibited the expression of p-CREB and IL-10, and promoted the expression of T-bet and IFN-γ in dNK cells. In the mice model, knockout of Lgals9 aggravated adverse pregnancy outcomes caused by T. gondii infection during pregnancy.
CONCLUSIONS: Toxoplasma gondii infection suppressed Gal-9 expression in dMφ by activating the JNK/FOXO1 signaling pathway, and reduction of Gal-9 contributed to dysfunction of dNK via Gal-9/Tim-3 interaction. This study provides new insights for the molecular mechanisms of the adverse pregnancy outcomes caused by T. gondii.
摘要：
背景：弓形虫感染通过影响蜕膜免疫细胞中免疫耐受分子的表达而导致不良妊娠结局。半乳糖凝集素-9（Gal-9）在蜕膜巨噬细胞（dMφ）中广泛表达，通过与免疫调节蛋白T细胞免疫球蛋白和含粘蛋白结构域的分子3（Tim-3）相互作用，对于维持正常妊娠至关重要。然而,弓形虫感染对dMφGal-9表达的影响，以及Gal-9表达水平的改变对蜕膜自然杀伤（dNK）细胞的母胎耐受功能的影响，仍然未知。
方法：记录弓形虫感染的C57BL/6和Lgals9-/-妊娠小鼠模型的妊娠结局。Gal-9,c-Jun氨基末端激酶(JNK)的表达,磷酸化JNK（p-JNK），用蛋白质印迹法检测叉头盒蛋白O1(FOXO1),流式细胞术或免疫荧光。通过染色质免疫沉淀-聚合酶链反应（ChIP-PCR）确定FOXO1与Lgals9启动子的结合。细胞外信号调节激酶(ERK)的表达,磷酸化ERK（p-ERK），cAMP反应元件结合蛋白（CREB），磷酸化CREB（p-CREB），在T细胞中表达的T-box（T-bet），白细胞介素10（IL-10），用蛋白质印迹法测定dNK细胞中的干扰素γ(IFN-γ)。
结果：弓形虫感染增加了dMφ中p-JNK和FOXO1的表达，由于FOXO1与Lgals9启动子的结合升高，导致Gal-9减少。Gal-9的下调增强了ERK的磷酸化,抑制dNK细胞中p-CREB和IL-10的表达,促进T-bet和IFN-γ的表达。在小鼠模型中,Lgals9基因敲除加重了妊娠期间弓形虫感染引起的不良妊娠结局.
结论：弓形虫感染通过激活JNK/FOXO1信号通路抑制dMφ中Gal-9的表达，Gal-9的减少通过Gal-9/Tim-3相互作用导致dNK功能障碍。本研究为弓形虫不良妊娠结局的分子机制提供了新的见解。
方法：记录弓形虫感染的C57BL/6和Lgals9-/-妊娠小鼠模型的妊娠结局。Gal-9,c-Jun氨基末端激酶(JNK)的表达,磷酸化JNK（p-JNK），用蛋白质印迹法检测叉头盒蛋白O1(FOXO1),流式细胞术或免疫荧光。通过染色质免疫沉淀-聚合酶链反应（ChIP-PCR）确定FOXO1与Lgals9启动子的结合。细胞外信号调节激酶(ERK)的表达,磷酸化ERK（p-ERK），cAMP反应元件结合蛋白（CREB），磷酸化CREB（p-CREB），在T细胞中表达的T-box（T-bet），白细胞介素10（IL-10），用蛋白质印迹法测定dNK细胞中的干扰素γ(IFN-γ)。
结果：弓形虫感染增加了dMφ中p-JNK和FOXO1的表达，由于FOXO1与Lgals9启动子的结合升高，导致Gal-9减少。Gal-9的下调增强了ERK的磷酸化,抑制dNK细胞中p-CREB和IL-10的表达,促进T-bet和IFN-γ的表达。在小鼠模型中,Lgals9基因敲除加重了妊娠期间弓形虫感染引起的不良妊娠结局.
结论：弓形虫感染通过激活JNK/FOXO1信号通路抑制dMφ中Gal-9的表达，Gal-9的减少通过Gal-9/Tim-3相互作用导致dNK功能障碍。本研究为弓形虫不良妊娠结局的分子机制提供了新的见解。
