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n. Any of several regulatory proteins, such as the interleukins and lymphokines, that are released by cells of the immune system and act as intercellular mediators in the generation of an immune response.

n. Any of various small regulatory proteins that regulate the cells of the immune system.

n. any of various protein molecules secreted by cells of the immune system that serve to regulate the immune system

"Swine and avian flus kill healthy people by invoking an overly aggressive immune response called a cytokine storm."

protein   

tnf    lymphokine    tumour necrosis factor    tumor necrosis factor   

T cell    chemokine    endogenous    immunoglobulin    dopamine    cortisol    estrogen    intracellular    proinflammatory    glucocorticoid