Immunohistochemical study of inducible nitric oxide synthase and tumour necrosis factor alpha response in turbot (Scophthalmus maximus) experimentally infected with Aeromonas salmonicida subsp. salmonicida. (September 2016)

• Record Type: Journal Article
• Authors: Coscelli, Germán; Bermúdez, Roberto; Ronza, Paolo; Losada, Ana Paula; Quiroga, María Isabel
• Is Part Of: Fish & shellfish immunology. Volume 56(2016:Sep.)
• Page Start: 294
• Page End: 302
• Publication Date: 2016-09
• Subjects: Aeromonas salmonicida -- Turbot -- Macrophages -- Tumour necrosis factor-α -- Inducible nitric oxide synthase -- Immunohistochemistry; TNFα tumour necrosis factor -- iNOS inducible nitric oxide synthase -- A. salmonicida Aeromonas salmonicida subspecies salmonicida -- NO nitric oxide -- ROS reactive oxygen species -- MMCs melanomacrophage centres; Fishes -- Immunology -- Periodicals; Shellfish -- Immunology -- Periodicals; Poissons -- Immunologie -- Périodiques; Crustacés -- Immunologie -- Périodiques; 571.9617
• DOI: 10.1016/j.fsi.2016.07.022
• Languages: English
• ISSNs: 1050-4648

Abstract

Abstract: Aeromonas salmonicida subsp. salmonicida represents one of the major threats in aquaculture, especially in salmonid fish and turbot farming. In order to fight bacterial infections, fish have an immune system composed by innate and specific cellular and humoral elements analogous to those present in mammals. However, innate immunity plays a primordial role against bacterial infections in teleost fish. Among these non-specific mechanisms, the production of nitric oxide (NO) by inducible nitric oxide synthase (iNOS) pathway and the tumour necrosis factor-alpha (TNFα) produced by mononuclear phagocytes, are two of the main immune effectors to eliminate bacterial pathogens. In this study, the distribution and kinetic of iNOS and TNFα-producing cells of kidney and spleen of turbot experimentally inoculated with A. salmonicida was assessed by immunohistochemistry. In control and challenged fish, individual iNOS + and TNFα + cells, showing a similar pattern of distribution, were detected. In challenged fish, the number of immunoreactive cells was significantly increased in the evaluated organs, as well as the melanomacrophage centres showed variable positivity for both antigens. These results indicate that A. salmonicida induced an immune response in challenged turbot, which involved the increase of the activity of iNOS and TNFα in the leukocytic population from kidney and spleen. Highlights: Immunohistochemistry of iNOS and TNFα in Aeromonas salmonicida infection was analyzed. A. salmonicida infection increased TNFα + cells in turbot haematopoietic organs. A. salmonicida infection increased iNOS + cells in turbot haematopoietic organs. Kidney was the main source of monocytes/macrophages expressing iNOS and TNFα antigen. Kidney and spleen play different roles in A. salmonicida infection.