Impact of VHSV on CIITA-mediated MHCII expression and antigen presentation in largemouth bass
Year: 2025
Type: article
Abstract: Viral hemorrhagic septicemia virus (VHSV) infection poses a significant threat to fish immunity by evading antigen presentation. Our previous study indicated that VHSV inhibited the transcriptional activation of MHC class II (MHCII) to impair antigen presentation in vitro, but the underlying mechanisms remain unclear. Here, we cloned and characterized the class II major histocompatibility complex transactivator (CIITA) in largemouth bass (Micropterus salmoides), a key regulator of MHCII expression, demonstrating that it activates MHCII transcription and possesses antiviral properties against VHSV. Following VHSV infection, CIITA and its downstream target MHCII were significantly downregulated in vivo. Further analysis revealed that the VHSV N protein degrades CIITA, primarily via its H3 and FCH domains, thereby impairing MHCII expression and antigen presentation. This study uncovers a critical mechanism through which VHSV inhibits adaptive immunity in fish and provides a theoretical basis for developing live-attenuated VHSV vaccines.
Source: Fish & Shellfish Immunology
Authors: Xiaobing Lu, Ziling Qin, Zhe Hu, Hao Huang, Jie Su, Xiaoru Zhang, Meisheng Yi, Kuntong Jia
Language: English
Subfield: Immunology
Field: Immunology and Microbiology
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $4,330
Funders: Natural Science Foundation of Guangxi Zhuang Autonomous Region, Scientific and Technological Planning Project of Guangzhou City, National Natural Science Foundation of China, Natural Science Foundation of Guangdong Province, Natural Science Foundation of Guangxi Province, Guangdong Special Support Plan
OpenAlex ID: W4409450237