Antas Paulo R Z, Ponte Carlos G G, Almeida Matheus R, Albuquerque Lawrence H P, Sousa-Vasconcelos Periela S, Pedro Thaíze, Gomes Natália L S, Moreira Otacílio C, Silva Fernanda C, Castello-Branco Luíz R R, Pinho Rosa T
1Laboratório de Imunologia Clínica, Oswaldo Cruz Institute, Fiocruz, Pavilhao Leonidas Deane, 4th Floor, Av. Brasil 4365, Rio de Janeiro, RJ 21045-900 Brazil.
2Laboratório de Biologia Molecular e Doenças Endêmicas, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil.
J Inflamm (Lond). 2019 Jul 15;16:18. doi: 10.1186/s12950-019-0223-1. eCollection 2019.
Caused by , tuberculosis (TB) is an extremely contagious disease predominantly affecting the lungs. TB is found worldwide and has a major impact on public health safety primarily due to its high mortality rate. Applied for over a hundred years as a preventive measure, BCG remains the only available TB vaccine. Only one seminal study about the apoptotic pathways induced by this vaccine in the monocytic lineage of the host cell has found the effects of BCG on regulation of apoptosis. The aim of this study was to explore beyond that pioneer study the pathway related to the in vitro cell-death pattern and the inflammatory response to the BCG vaccine in human monocytes.
Cohorts of HIV-negative volunteers were enrolled: adult Healthy Donors (HD) and neonates' Umbilical Cord Blood (UCB) individuals. Host mononuclear cells were infected with the Moreau strain of BCG vaccine at 16, 24, 48, and 72 h. The Real-Time RT-PCR for TRADD, Bcl-2, and Caspases-1 and -3 were performed, and supernatants were assayed in parallel for Caspase-1, NLRP3, HO-1, and IL-1β levels whereas caspases were assessed intracellularly. The effect of a BCG infection in monocytes was characterized via a metabolic activity assay by LDH release profiles.
Overall, the BCG vaccine induced significantly higher Caspase-1 and Bcl-2 mRNA levels in both the HD and UCB groups (-value ≤0.05). In addition, a significant increase solely in Caspase-1 protein levels was also noted in both HD and UCB (-value ≤0.05) notwithstanding the absence of any damaged cell membranes.
Our data directly corroborate other findings showing that BCG Moreau led to an increased secretion of IL-1β but not IL-18, two Caspase-1-activated cytokines, and are also in support of the model that the BCG Moreau infection of human mononuclear cells may induce a cell-death pattern involving Caspase-1 activation.
结核病（TB）具有极高的传染性，主要影响肺部。结核病在全球范围内均有发现，因其高死亡率对公共卫生安全产生重大影响。卡介苗（BCG）作为预防措施已应用了一百多年，仍是唯一可用的结核病疫苗。仅有一项关于该疫苗在宿主细胞单核细胞系中诱导凋亡途径的开创性研究发现了卡介苗对细胞凋亡调节的影响。本研究的目的是在该开创性研究的基础上，进一步探索与体外细胞死亡模式及人类单核细胞对卡介苗疫苗炎症反应相关的途径。
招募了HIV阴性志愿者队列：成年健康供体（HD）和新生儿脐带血（UCB）个体。宿主单核细胞在16、24、48和72小时时用卡介苗疫苗莫罗菌株感染。进行TRADD、Bcl-2以及半胱天冬酶-1和-3的实时逆转录聚合酶链反应（Real-Time RT-PCR），同时对上清液进行半胱天冬酶-1、NLRP3、血红素加氧酶-1（HO-1）和白细胞介素-1β（IL-1β）水平的检测，而半胱天冬酶则在细胞内进行评估。通过乳酸脱氢酶（LDH）释放曲线的代谢活性测定来表征卡介苗感染对单核细胞的影响。
总体而言，卡介苗疫苗在HD组和UCB组中均显著诱导了更高的半胱天冬酶-1和Bcl-2 mRNA水平（P值≤0.05）。此外，尽管没有任何细胞膜受损，但在HD组和UCB组中也均仅观察到半胱天冬酶-1蛋白水平显著升高（P值≤0.05）。
我们的数据直接证实了其他研究结果，即卡介苗莫罗菌株导致IL-1β而非IL-18（两种由半胱天冬酶-1激活的细胞因子）分泌增加，并且也支持卡介苗莫罗菌株感染人类单核细胞可能诱导涉及半胱天冬酶-1激活的细胞死亡模式这一模型。
