Final answer:
A) they communicate between cells to instigate an immune response
Cytokines in the immune system primarily function as messengers that communicate between cells to trigger
The general function of cytokines in the immune system is to communicate between cells to instigate an immune response. Cytokines are crucial chemical messengers that regulate various aspects of immune cells, such as differentiation, proliferation, and gene expression, leading to different immune responses. They are secreted by white blood cells and infected cells, binding to and inducing nearby uninfected cells to produce more cytokines in a positive feedback loop. This results in a burst of cytokine production which, among their many functions, include promoting inflammation, phagocytosis, and adaptive immune responses through cells like T cells and macrophages. They are instrumental in facilitating the coordination of both early induced responses and the more sophisticated adaptive immune responses.
Interferons, a class of cytokines, are released by cells in response to pathogens as a warning to uninfected cells to undertake protective strategies, such as inhibiting viral replication and activating immune cells. Another type, interleukins, are largely produced by immune cells and aid in orchestrating the immune system's defense against invaders. Cytokines and chemokines together play a central role in the modulation and signaling of the immune system's response to threats.