School of Marine Sciences, Sun Yat-sen University, State Key Laboratory of Biocontrol/Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangzhou, People's Republic of China.
Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering/Guangdong Provincial Key Laboratory of Aquatic Economic Animals, Sun Yat-sen University, Guangzhou, People's Republic of China.
J Immunol. 2024 Oct 15;213(8):1187-1201. doi: 10.4049/jimmunol.2400240.
In aquatic ectotherms, temperature plays a pivotal role in biological processes and the prevalence of viral diseases; however, the molecular mechanisms underlying these effects are not fully elucidated. In this study, we investigate the impact of elevated temperatures (32°C) on the immune response against white spot syndrome virus (WSSV) in shrimp (Litopenaeus vannamei). Our findings reveal that higher water temperatures, specifically 32°C, significantly inhibit WSSV replication and pathogenicity, thereby enhancing the survival rates of infected shrimp. Through transcriptome analysis and in vivo experiments, we identified heat shock protein 70 (HSP70) as a key factor in this thermal regulation of immunity. Shrimp maintained at 32°C, with silenced HSP70 expression, exhibited increased viral loads and reduced survival, underscoring the crucial protective role of HSP70 against WSSV at elevated temperatures. Our results further uncover the HSP70-Toll4-Dorsal-antimicrobial peptide (AMP) pathway as a key mediator of WSSV resistance at elevated temperatures. This pathway involves the interaction of HSP70 with the Toll4 receptor, resulting in the phosphorylation of Dorsal and the consequent modulation of expression of AMPs such as the anti-LPS factor (ALF) and lysozyme (LYZ) families. Taken together, these findings advance our understanding of temperature's role in disease dynamics in aquatic ectotherms, especially the unexpected roles of HSP70 in shrimp in facilitating the innate immune system's response to thermal stress, and suggest new approaches to managing WSSV in shrimp farming, such as environmental temperature control or HSP70 induction.
在水生变温动物中，温度在生物过程和病毒疾病的流行中起着关键作用；然而，这些影响的分子机制尚未完全阐明。在这项研究中，我们调查了升高的温度（32°C）对虾（凡纳滨对虾）对白质斑点综合征病毒（WSSV）免疫反应的影响。我们的研究结果表明，更高的水温，特别是 32°C，显著抑制 WSSV 的复制和致病性，从而提高了感染虾的存活率。通过转录组分析和体内实验，我们确定热休克蛋白 70（HSP70）是这种免疫热调节的关键因素。在 32°C 下保持的 HSP70 表达沉默的虾，其病毒载量增加，存活率降低，这突出了 HSP70 在高温下对 WSSV 的关键保护作用。我们的研究结果进一步揭示了 HSP70-Toll4-Dorsal-抗菌肽（AMP）途径是高温下抵抗 WSSV 的关键介质。该途径涉及 HSP70 与 Toll4 受体的相互作用，导致 Dorsal 的磷酸化，继而调节 AMP 的表达，如抗脂多糖因子（ALF）和溶菌酶（LYZ）家族。总之，这些发现提高了我们对温度在水生变温动物疾病动态中的作用的理解，特别是 HSP70 在虾中促进先天免疫系统对热应激的反应的意外作用，并为虾养殖中的 WSSV 管理提出了新的方法，例如环境温度控制或 HSP70 诱导。
