How do cytokines function?
a They are secreted by lysozomes into the phagosomes of neutrophils to enhance the killing of ingested microbes within those organelles.
b They are secreted by one cell type, then work as a series of serum proteins to produce holes in the cytoplasmic membranes of microbes to directly lyse them.
c They are secreted by microbes that have been engulfed by phagocytes, causing those cells to produce destructive enzymes and undergo apoptosis.
d They are secreted by one cell type, then bind to a receptor on target cell causing a signal within that cell that turns on (or off) certain genes to achieve a response.
e They are produced by several cell types and bind directly to microbes to enhance their chance of being ingested, in a process called opsonization.