Domínguez-Martínez Diana Alhelí, Pérez-Flores Mayra Silvia, Núñez-Avellaneda Daniel, Torres-Flores Jesús M, León-Avila Gloria, García-Pérez Blanca Estela, Salazar Ma Isabel
Laboratorio de Inmunología Celular e Inmunopatogénesis, Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México CP 11340, Mexico.
Unidad de Investigación en Virología y Cáncer, Hospital Infantil de México Federico Gómez, Ciudad de México CP 06720, Mexico.
Pathogens. 2024 Apr 10;13(4):306. doi: 10.3390/pathogens13040306.
In pathogen recognition, the nucleotide-binding domain (NBD) and leucine rich repeat receptors (NLRs) have noteworthy functions in the activation of the innate immune response. These receptors respond to several viral infections, among them NOD2, a very dynamic NLR, whose role in dengue virus (DENV) infection remains unclear. This research aimed to determine the role of human NOD2 in THP-1 macrophage-like cells during DENV-2 infection. NOD2 levels in DENV-2 infected THP-1 macrophage-like cells was evaluated by RT-PCR and Western blot, and an increase was observed at both mRNA and protein levels. We observed using confocal microscopy and co-immunoprecipitation assays that NOD2 interacts with the effector protein MAVS (mitochondrial antiviral signaling protein), an adaptor protein promoting antiviral activity, this occurring mainly at 12 h into the infection. After silencing , we detected increased viral loads of DENV-2 and lower levels of IFN-α in supernatants from THP-1 macrophage-like cells with NOD2 knock-down and further infected with DENV-2, compared with mock-control or cells transfected with Scramble-siRNA. Thus, NOD2 is activated in response to DENV-2 in THP-1 macrophage-like cells and participates in IFN-α production, in addition to limiting virus replication at the examined time points.
在病原体识别过程中，核苷酸结合结构域（NBD）和富含亮氨酸重复序列受体（NLRs）在激活先天免疫反应中具有重要作用。这些受体可对多种病毒感染产生应答，其中NOD2是一种非常活跃的NLR，其在登革病毒（DENV）感染中的作用尚不清楚。本研究旨在确定人NOD2在DENV-2感染期间THP-1巨噬细胞样细胞中的作用。通过逆转录聚合酶链反应（RT-PCR）和蛋白质免疫印迹法评估DENV-2感染的THP-1巨噬细胞样细胞中NOD2的水平，结果显示在mRNA和蛋白质水平均有升高。我们利用共聚焦显微镜和免疫共沉淀试验观察到，NOD2与效应蛋白线粒体抗病毒信号蛋白（MAVS）相互作用，MAVS是一种促进抗病毒活性的衔接蛋白，这种相互作用主要发生在感染后12小时。在敲低NOD2后，与模拟对照或转染乱序小干扰RNA（Scramble-siRNA）的细胞相比，我们检测到敲低NOD2的THP-1巨噬细胞样细胞在进一步感染DENV-2后，其上清液中DENV-2的病毒载量增加，而干扰素-α（IFN-α）水平降低。因此，在THP-1巨噬细胞样细胞中，NOD2可被DENV-2激活，并参与IFN-α 的产生，此外在检测的时间点还可限制病毒复制。
