Figure 6. Proteasome inhibitors block processing and release of IL-1ß.

A) LPS-primed WT BMDM were incubated in control medium or medium containing 10 ng/ml ricin or 25 µg/ml cycloheximide for 4 h. MG-132 (30 µM) or Bortezimib (0.5 µM) was included as indicated. Secreted IL-1ß was measured by ELISA in triplicate wells. B) LPS-primed WT BMDM were incubated in the presence or absence of MG-132 for 4 hours, in the presence or absence of inhibitors of protein synthesis, as indicated. Cell lysates (cell) and culture medium (medium) were examined by immunoblotting. C) LPS-primed or unprimed WT BMDM were or exposed to MSU, MG-132, or both for 4 h, as indicated. Cell lysates (cell) and culture medium (medium) were examined by immunoblotting.