Fish immune system, mucosal immunity and functions of IL-1β, TNF-α and IL-18 proinflammatory cytokines

Abstract

Fish exposed to various threats in the aquatic environment and respond to these with the immune responses which has developed in the evolutionary process. The immune system of teleost fish consists of the fluid and cellular factors of both natural and acquired immunity. Mucosa associated lymphoid tissues are a part of fish immune system and equipped with cells of natural and adaptive immunity. The organs in which all these cells and molecules are formed, matured and included in the system are called lymphoid organs. Cytokines, which are small glycoproteins, play critical roles in immunity. Their main roles in the immune system are to regulate immune responses and to enable communication between cells. In this review, the literature on the main factors of the fish immune system, mucosal immunity, the functions of the primary lymphoid organs, and proinflamatory cytokines IL-1β, TNF-α and IL-18 were collected. Furthermore, the functions of specified cytokines were aimed to clarify.