MANIPULATION OF DISTINCT NF-KAPPA-B PROTEINS ALTERS INTERLEUKIN-1-BETA-INDUCED HUMAN RHEUMATOID SYNOVIAL FIBROBLAST PROSTAGLANDIN E(2) FORMATION

Interleukin 1 beta (IL-1 beta) up-regulates human rheumatoid synovial fibroblast (RSF) 85-kDa phospholipase A(2) (PLA(2)) and mitogen-induci ble cyclooxygenase (COX) II. Promoter regions for these genes contain a motif that closely resembles the ''classic'' NF kappa B consensus si te, Immunoblot analysis identified NF kappa B1 (p50), RelA (p65), and c-Rel in RSF, Upon IL-1 beta-stimulation, p65 and c-Rel but not p50 pr otein levels were reduced suggesting nuclear translocation, IL-1 beta- induced RSF nuclear extracts contained a p65-containing complex, which bound to the classical NF kappa B consensus motif, An NF kappa B clas sical oligonucleotide decoy produced a concentration-dependent decreas e in IL-1-stimulated PGE(2) production (IC50 = similar to 2 mu M), ind icating a role of NF kappa B. Utilization of antisense technology show ed that p65 but not p50 or c-Rel mediated IL-1 beta-stimulated PGE(2) formation, Treated RSF could not transcribe COX II or 85-kDa PLA(2) mR NA, which reduced their respective proteins, Interestingly, stimulated IL-8 production was not inhibited by the classical NF kappa B decoy b ut was reduced by treatment with antisense to both p65 and c-Rel suppo rting preferential binding of c-Rel-p65 to the ''alternative'' IL-8 ka ppa B motif, Taken together, these data provide the first direct evide nce for a role of p65 in COX II and 85-kDa PLA(2) gene induction and s upport the IL-1 activation and participation of distinct NF kappa B pr otein dimers in RSF prostanoid and IL-8 formation.