A tandem-repeat galectin-4 from Nile tilapia (Oreochromis niloticus) is involved in immune response to bacterial infection via mediating pathogen recognition and opsonization. (November 2020)

• Record Type: Journal Article
• Authors: Niu, Jinzhong; Liu, Xinchao; Zhang, Zhiqiang; Huang, Yu; Tang, Jufen; Wang, Bei; Lu, Yishan; Cai, Jia; Jian, Jichang
• Is Part Of: Molecular immunology. Volume 127(2020:Nov.)
• Page Start: 67
• Page End: 77
• Publication Date: 2020-11
• Subjects: Galectin-4 -- Nile tilapia -- Monocytes/macrophages -- Streptococcus agalactiae -- Pathogen recognition; Immunochemistry -- Periodicals; Molecular biology -- Periodicals; Immunochemistry -- Periodicals; Allergy and Immunology -- Periodicals; Molecular Biology -- Periodicals; Immunochimie -- Périodiques; Biologie moléculaire -- Périodiques; Immunochemistry; Molecular biology; Periodicals; Electronic journals; 571.96
• DOI: 10.1016/j.molimm.2020.08.022
• Languages: English
• ISSNs: 0161-5890

Abstract

Highlights: A tandem-repeat galectin-4 ( OnGal-4 ) was identified and characterized from Nile tilapia, Oreochromis niloticus. OnGal-4 was widely distributed in various tissues and was induced by bacterial infection in vivo or in vitro . rOnGal-4 had bacterial binding and agglutination activities, as well as enhanced the bactericidal activity and cytokines expressions of Mo/MΦ. OnGal-4 overexpression in vivo could increase tilapia survival rate by reducing tissue damage and inflammation. Abstract: Galectins are the family of carbohydrate-binding proteins that participate in host-pathogen interaction. In this study, a galectin-4 homolog ( OnGal-4 ) from Nile tilapia ( Oreochromis niloticus ) was characterized. The open reading frame of OnGal-4 was 1194 bp, encoding a peptide of 397 amino including two CRD regions and two carbohydrate recognition sites. OnGal-4 mRNA was expressed in all examined tissues with the highest level in spleen. After Streptococcus agalactiae ( S.agalactiae ) challenge, the OnGal-4 expression was up-regulated in the spleen, head kidney, brain, and monocytes/macrophages (Mo/MΦ). The in vitro experiments showed that recombinant OnGal-4 (rOnGal-4) protein could bind and agglutinate S.agalactiae and A.hydrophila . Also, rOnGal-4 could induce cytokines expressions and increased bactericidal activity of Mo/MΦ. Further in vivo analysis indicated that OnGal-4 overexpression could protect O.niloticus from S.agalactiae infection through modulating inflammation response. Our study suggested that OnGal-4 could improve immune response against bacterial infection by mediating pathogen recognition and opsonization.