Mo Jinfeng, Li Jiadong, Qiu Li, Wang Yiqing, Mu Liangliang, Ye Jianmin
Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, Institute of Modern Aquaculture Science and Engineering, School of Life Sciences, South China Normal University, Guangzhou 510631, China.
Guangdong Provincial Water Environment and Aquatic Products Security Engineering Technology, Research Center, Guangzhou Key Laboratory of Aquatic Animal Diseases and Waterfowl Breeding, College of Animal Science and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China.
Int J Mol Sci. 2024 Feb 21;25(5):2508. doi: 10.3390/ijms25052508.
Collectin-K1 (CL-K1) is a multifunctional C-type lectin that has been identified as playing a crucial role in innate immunity. It can bind to carbohydrates on pathogens, leading to direct neutralization, agglutination, and/or opsonization, thereby inhibiting pathogenic infection. In this study, we investigated a homolog of CL-K1 (CL-K1) in Nile tilapia () and its role in promoting the clearance of the pathogen () and enhancing the antibacterial ability of the fish. Our analysis of bacterial load displayed that substantially reduced the amount of in tissues of the liver, spleen, anterior kidney, and brain in Nile tilapia. Furthermore, examination of tissue sections revealed that CL-K1 effectively alleviated tissue damage and inflammatory response in the liver, anterior kidney, spleen, and brain tissue of tilapia following infection. Additionally, 1 was found to decrease the expression of the pro-inflammatory factor and migration inhibitor , while increasing the expression of anti-inflammatory factor and chemokine in the spleen, anterior kidney, and brain tissues of tilapia. Moreover, statistical analysis of survival rates demonstrated that CL-K1 significantly improved the survival rate of tilapia after infection, with a survival rate of 90%. Collectively, our findings suggest that CL-K1 plays a vital role in the innate immune defense of resisting bacterial infection in Nile tilapia. It promotes the removal of bacterial pathogens from the host, inhibits pathogen proliferation in vivo, reduces damage to host tissues caused by pathogens, and improves the survival rate of the host.
凝集素-K1（CL-K1）是一种多功能C型凝集素，已被确定在先天免疫中起关键作用。它可以与病原体上的碳水化合物结合，导致直接中和、凝集和/或调理作用，从而抑制病原体感染。在本研究中，我们调查了尼罗罗非鱼中CL-K1的同源物（CL-K1）及其在促进病原体清除和增强鱼的抗菌能力方面的作用。我们对细菌载量的分析表明，CL-K1显著减少了尼罗罗非鱼肝脏、脾脏、前肾和脑组织中的嗜水气单胞菌数量。此外，组织切片检查显示，CL-K1有效减轻了嗜水气单胞菌感染后罗非鱼肝脏、前肾、脾脏和脑组织的组织损伤和炎症反应。此外，发现CL-K1降低了促炎因子肿瘤坏死因子-α和迁移抑制因子RANTES的表达，同时增加了罗非鱼脾脏、前肾和脑组织中抗炎因子白细胞介素-10和趋化因子CCL20的表达。此外，存活率的统计分析表明，CL-K1显著提高了罗非鱼感染后的存活率，存活率为90%。总的来说，我们的研究结果表明，CL-K1在尼罗罗非鱼抵抗细菌感染的先天免疫防御中起着至关重要的作用。它促进从宿主体内清除细菌病原体，抑制病原体在体内增殖，减少病原体对宿主组织的损伤，并提高宿主的存活率。
