Jang Yo-Seb, Yoon Su-Young, Krishnan Rahul, Oh Myung-Joo
Department of Aqualife Medicine, Chonnam National University, Yeosu, Republic of Korea.
Department of Aquatic Animal Health Management, Faculty of Fisheries, Kerala University of Fisheries and Ocean Studies, Kerala, India.
Fish Shellfish Immunol. 2024 Dec;155:110004. doi: 10.1016/j.fsi.2024.110004. Epub 2024 Nov 2.
Viral hemorrhagic septicemia virus (VHSV) is a pathogen that causes hemorrhagic septicemia in olive flounder at water temperatures below 15 °C, leading to symptoms such as abdominal swelling due to ascites and muscle hemorrhaging, and in severe cases, mortality. In this study, we investigated the proliferation of NCCs, the transcriptional analysis of CD4 and CD8, and the expression of pro-inflammatory cytokines (IL-1β, IL6, TNFα) and the cytokines (IL12, IL15, IFN-1β, IFNγ) involved in cytotoxic cell activation in the kidney of olive flounder during VHSV infection at suboptimal temperature (17 °C) and following a shift to optimal temperature (10 °C). Following viral infection, the population of NCCs and CD8 gene expression steadily increased. Meanwhile, IL12, IL15, and IFN-1β levels exhibited an early surge, reaching their peak within 1-2 days post-challenge at 17 °C. Notably, in olive flounder that were re-challenged with VHSV at 10 °C after an initial challenge at 17 °C, there was a rapid and robust expansion of NCCs and increased CD4 and CD8 gene expression, demonstrating the mounting of immune memory by NCCs and an efficient adaptive immune response from CD4 and CD8 T cells against VHSV infection.
病毒性出血性败血症病毒（VHSV）是一种病原体，在水温低于15°C时会导致牙鲆患上出血性败血症，引发腹水导致腹部肿胀和肌肉出血等症状，严重时会造成死亡。在本研究中，我们调查了牙鲆在次优温度（17°C）感染VHSV期间以及随后转移到最佳温度（10°C）后，肾脏中中性粒细胞（NCCs）的增殖、CD4和CD8的转录分析、促炎细胞因子（IL-1β、IL6、TNFα）以及参与细胞毒性细胞激活的细胞因子（IL12、IL15、IFN-1β、IFNγ）的表达情况。病毒感染后，NCCs的数量和CD8基因表达稳步增加。同时，IL12、IL15和IFN-1β水平早期出现激增，在17°C攻击后1-2天内达到峰值。值得注意的是，在17°C初次感染后再在10°C用VHSV攻击的牙鲆中，NCCs迅速且大量扩增，CD4和CD8基因表达增加，表明NCCs产生了免疫记忆，CD4和CD8 T细胞对VHSV感染产生了有效的适应性免疫反应。
