Effect of PAO on the production of IL-1β and IL-1RA by OCIM2 and OCI/AML3 cells. Cells were incubated in the presence or absence of 1.0 μmol/L PAO for 24 hours. The amount of IL-1β (upper panel) and IL-1RA (lower panel) produced by these cells was then assessed by ELISA as described in Materials and Methods.