文献类型：期刊文献

英文题名：Pathogenicity and tissue-specific immune responses of Procypris merus challenged with Shewanella algae isolated from aquaculture water

作者：Wei, Dongdong[1,3,5]; Han, Shuyu[1,4]; Yu, Qing[1,3]; Huang, Lin[1,3]; Xu, Weijiang[1,3,5]; Cai, Jia[3,5]; Huang, Jing[1,3]; Lai, Junxiang[1,3]; Yu, Ermeng[3]; Ling, Fei[3,6]; Liu, Mingzhu[1,3]; Lia, Pengfei[2,5]

机构：[1] Guangxi Academy of Sciences, China; [2] Guangxi Minzu University, China; [3] Guangxi Academy of Marine Sciences, Guangxi Laboratory of Oceanography, Guangxi Key Laboratory of Aquatic Biotechnology and Modern Ecological Aquaculture, Guangxi Engineering Research Center for Fishery Major Diseases Control and Efficient Healthy Breeding Industrial Technology [GERCFT], Guangxi Academy of Sciences, Nanning, China; [4] Guangxi Fisheries Technology Extension Station, Nanning, China; [5] Guangdong Engineering Technology Research Center of Indigenous Valuable Fish Reproductive Regulation and Breeding, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture, Fisheries College, Guangdong Ocean University, Zhanjiang, China; [6] College of Animal Science and Technology, Northwest A&F University, Yangling, China

年份：2026

外文期刊名：SSRN

收录：EI(收录号：20260205609)

语种：英文

外文关键词：Antibiotics - Aquaculture - Bacteria - Explosives - Gene expression - Immune system - Muscle - Tissue engineering - Water

外文摘要：Shewanella algae was isolated from bullfrog aquaculture water to evaluate its pathogenicity to Rice flower carp (Procypris merus) and to systematically characterize the immune responses in different tissues post-infection. The isolate was identified, subjected to antimicrobial susceptibility testing, and screened for virulence and resistance genes. The median lethal concentration (LD50) was determined by artificial challenge, and histopathological changes were observed. The expression levels of IL-8, TNF-α, C2, IL-1β, TLR-4, and HSP70 in the liver, spleen, kidney, intestine, and muscle at 0–72 h post-infection were measured by qRT-PCR. The isolate was identified as Shewanella algae. It was sensitive to gentamicin, enrofloxacin, and polymyxin B, and carried seven virulence genes and five resistance genes. The LD50 was 1.0 × 107 CFU/mL. Infected fish showed ascites, anal swelling, hepatosplenomegaly, and tissue damage. Immune gene expression exhibited tissue specificity: hepatic TNF-α peaked at 24 h (6.90-fold); splenic IL-1β showed an explosive upregulation at 24 h (6.56-fold), with TLR-4 concurrently upregulated (2.21-fold); renal HSP70 was rapidly upregulated at 12 h (3.09-fold); intestinal IL-8 (3.13-fold at 12 h) and C2 (5.41-fold at 48 h) were upregulated; muscular C2 (4.47-fold) and HSP70 (3.74-fold) were also upregulated. The spleen, liver, and kidney were the primary responsive organs. This study is the first to demonstrate that an environmental isolate of S. algae from aquaculture water is pathogenic to the freshwater Rice flower carp, and reveals a tissue-specific immune response pattern centered on the spleen (IL-1β/TLR-4), liver (TNF-α/C2), and kidney (HSP70). ? 2026, The Authors. All rights reserved.