OC.03.4 INFLIXIMAB THREE-DOSE INDUCTION REGIMEN IN ACUTE SEVERE ULCERATIVE COLITIS: EARLY AND LATE OUTCOME AND PREDICTORS OF COLECTOMY

significantly decreased LPS–induced TNFα in PBMC-derived M8 from UC, CD and controls. In contrast, in M8 from biopsies, pretreatment with nicotine selectively decreased LPS-induced intracellular TNFα in cells derived from UC (from 20.85±7.13 to 12.44±7.17 TNFα %fluorescence, p<0,05), while no effect was observed in cells from CD and controls. Conclusions: In M8 derived from PBMC, nicotine decreases LPS-induced TNFα production. In contrast, in intestinal M8 nicotine selectively decreases TNFα production only in cells from UC patient, and this is associated with increased nicotinic receptor levels. Thus, higher levels of nicotinic receptor could explain the selective modulatory effect of nicotine in UC.