Faculty of Veterinary Medicine, Norwegian University of Life Sciences (NMBU), Ås, Norway.
SINTEF AS, Department of Biotechnology and Nanomedicine, Trondheim, Norway.
Dev Comp Immunol. 2022 Feb;127:104268. doi: 10.1016/j.dci.2021.104268. Epub 2021 Sep 25.
Monitoring fish welfare has become a central issue for the fast-growing aquaculture industry, and finding proper biomarkers of stress, inflammation and infection is necessary for surveillance and documentation of fish health. In this study, a proteomic approach using mass spectrometry was applied to identify indicators of the acute response in Atlantic salmon blood plasma by comparing Aeromonas salmonicida subsp. salmonicida infected fish and non-infected controls. The antimicrobial proteins cathelicidin (CATH), L-plastin (Plastin-2, LCP1) and soluble toll-like receptor 5 (sTLR5) were uniquely or mainly identified in the plasma of infected fish. In addition, five immune-related proteins showed significantly increased expression in plasma of infected fish: haptoglobin, high affinity immunoglobulin Fc gamma receptor I (FcγR1, CD64), leucine-rich alpha 2 glycoprotein (LRG1), complement C4 (C4) and phospholipase A2 inhibitor 31 kDa subunit-like protein. However, various fibrinogen components, CD209 and CD44 antigen-like molecules decreased in infected fish. Selected biomarkers were further verified by Western blot analysis of plasma and real time PCR of spleen and liver, including CATH1, CATH2 and L-plastin. A significant increase of L-plastin occurred as early as 24 h after infection, and a CATH2 increase was observed from 72 h in plasma of infected fish. Real time PCR of selected genes confirmed increased transcription of CATH1 and CATH2. In addition, serum amyloid A mRNA significantly increased in liver and spleen after bacterial infection. However, transcription of L-plastin was not consistently induced in liver and spleen. The results of the present study reveal novel and promising biomarkers of the acute phase response and inflammation in Atlantic salmon.
监测鱼类福利已成为快速发展的水产养殖业的核心问题，寻找适当的应激、炎症和感染生物标志物对于监测和记录鱼类健康状况是必要的。在这项研究中，通过比较感染和未感染的对照，使用质谱的蛋白质组学方法来鉴定大西洋鲑鱼血液血浆中急性反应的指标。抗菌蛋白 cathelicidin（CATH）、L-plastin（Plastin-2，LCP1）和可溶性 toll 样受体 5（sTLR5）在感染鱼的血浆中被唯一或主要鉴定。此外，五种免疫相关蛋白在感染鱼的血浆中表达显著增加：触珠蛋白、高亲和力免疫球蛋白 Fc 受体 I（FcγR1，CD64）、富含亮氨酸的 alpha 2 糖蛋白（LRG1）、补体 C4（C4）和磷脂酶 A2 抑制剂 31 kDa 亚基样蛋白。然而，感染鱼的各种纤维蛋白原成分、CD209 和 CD44 抗原样分子减少。通过对血浆进行 Western blot 分析和对脾脏和肝脏进行实时 PCR 分析，进一步验证了选定的生物标志物，包括 CATH1、CATH2 和 L-plastin。L-plastin 的显著增加早在感染后 24 小时就发生了，并且在感染鱼的血浆中观察到 CATH2 从 72 小时增加。对选定基因的实时 PCR 证实了 CATH1 和 CATH2 的转录增加。此外，在肝脏和脾脏中，血清淀粉样蛋白 A mRNA 在细菌感染后显著增加。然而，L-plastin 的转录在肝脏和脾脏中并未一致诱导。本研究的结果揭示了大西洋鲑鱼急性相反应和炎症的新的有前途的生物标志物。
