U-937 cells are of myeloid lineage and thus secrete a large number of cytokines and chemokines either constitutively (e.g., IL-1 and GM-CSF) or in response to soluble stimuli. TNFα and recombinant GM-CSF for example independently promote IL-10 production in U937 cells. This cell line is therefore widely used for cytokine level read-outs as a result of exposure to various chemical compounds. Namely, production of IL-1β, IL-6, IL-8, IL-10, TNF-α, iNOS, COX-2 and NF-κB is commonly measured.
