The Mediterranean sea bass Dicentrarchus labrax: A marine model species in fish immunology

Abstract

The Mediterranean sea bass, Dicentrarchus labrax, is a species of great interest due to the extensive knowledge accumulated about its immune system and the application of these findings in aquaculture health management. The available data indicate that sea bass has the morphological and immunological features typical of jawed vertebrates, with minor anatomical differences compared to evolutionarily older teleosts. Namely, all the master genes coding for Tc and Th T cells have been found to be expressed, together with related cytokine families, and Tc/Th activities can be investigated using in vitro models. The B lymphocytes produce IgM/IgT/IgD antibodies in response to antigenic/vaccine stimulation and maintain an IgM-B cell memory for antigens and vaccines. Mucosal and systemic immunity with associated leukocyte populations is present and functional, and it can be modulated by substances added to water or food. Studies on the ontogenesis of immune components defined precise points of lymphocyte development during larval life. Finally, the central nervous system of sea bass has been shown to contain resident lymphocytes, whose number can be modulated by pathogenic infection. Based on the available knowledge summarized in this review, it can be certainly assumed that the Dicentrarchus labrax is a valuable marine model species for studies in immunology and physiology of vertebrates.