Fish cytokines: current research and applications

Abstract

Cytokines are low molecular weight glycoproteins involved in the regulation of the immune system, and more than 100 cytokines have hitherto been identified in humans. Cytokines similar to those found in humans have also been found in fish. The innate immune response of fish can be examined by using cytokines as markers. We developed a multiplex reverse transcription–polymerase chain reaction assay to analyze the expression of various cytokine genes. Using this assay, we were able to investigate the fish immune response when it had been activated by immunostimulants. The involvement of inflammatory cytokines, such as interleukin-1β, in the immune system of fish was revealed following administration of an immunostimulant.