Functional characterization of complement factor H in host defense against bacterial pathogen in Nile tilapia (Oreochromis niloticus). Issue 129 (October 2022)

• Record Type: Journal Article
• Authors: Wei, Xiayi; Wu, Zhelin; Zhang, Tingyun; Lei, Yang; Chen, Meng; Yang, Yanjian; Gao, Along; Guo, Zheng; Ye, Jianmin
• Is Part Of: Fish & shellfish immunology. Issue 129(2022)
• Page Start: 114
• Page End: 126
• Publication Date: 2022-10
• Subjects: Oreochromis niloticus -- Complement factor H -- Bacterial infection -- Phagocytosis -- Inflammatory response; Fishes -- Immunology -- Periodicals; Shellfish -- Immunology -- Periodicals; Poissons -- Immunologie -- Périodiques; Crustacés -- Immunologie -- Périodiques; 571.9617
• DOI: 10.1016/j.fsi.2022.08.049
• Languages: English
• ISSNs: 1050-4648

Abstract

Abstract: Complement factor H (CFH), a multifunctional soluble complement regulatory protein, can bind to a variety of pathogens and play a crucial role in host innate immune defense. To explore the functional characteristics of CFH ( OnCFH ) in Nile tilapia ( Oreochromis niloticus ), we cloned and characterized the open reading frame (ORF) of OnCFH in this study. The full-length of OnCFH ORF is 1359 bp, encoding 452 aa for a 48.85 kDa peptide, and its predicted structure containing six short complement-like repeats (SCRs). The analysis of tissue distribution showed that OnCFH was constitutively expressed in all tested tissues, with the highest in the liver. Upon Streptococcus agalactiae and Aeromonas hydrophila stimuli in vivo and in vitro, OnCFH mRNA transcript was significantly upregulated in head kidney tissue as well as head kidney monocytes/macrophages. Further, the recombinant OnCFH protein ((r)OnCFH) could bind to pathogenic bacteria in a dose-dependent. Moreover, it got involved in the regulation of inflammation as well as phagocytosis of monocytes/macrophages. The knockdown of OnCFH remarkably decreased the amount of bacteria in the head kidney. In summary, our data demonstrated that OnCFH could participate in the immune response of Nile tilapia against bacterial infection. Highlights: The CFH gene was identified in Nile tilapia ( OnCFH ). OnCFH expression was significantly up-regulated following the challenges with pathogenic bacteria ( in vivo and in vitro ). Recombinant OnCFH was able to recognize and bind with S. galactiae and A. hydrophila. Recombinant OnCFH could participate in the regulation of phagocytosis and inflammatory response.