Association between tumor necrosis factor-alpha and Fc-gamma receptor polymorphisms with infliximab in Crohn's disease.

BACKGROUND/AIMS The associations between tumor necrosis factor-alpha (TNF-alpha) and Fcgamma receptor (FcgammaR) polymorphisms with infliximab (IFX) treatment of Crohn's disease (CD) are not well known. The aim of this study was to evaluate the association between these polymorphisms and IFX treatment of CD. METHODOLOGY DNA was obtained from 41 CD patients (13 females, 28 males). TNF-alpha and FcgammaR polymorphisms were determined by the polymerase chain reaction-based restriction fragment length polymorphism method. Patients were given IFX 5 mg/kg intravenously and were followed prospectively for 8 weeks. The CD activity index (CDAI) was measured before and 8 weeks after treatment. Patients were classified as responders or non-responders according to the CDAI. RESULTS The distribution of TNF-alpha, FcgammaRIIA, and FcgammaRIIIA genotypes was not significantly different between responders and non-responders 8 weeks after treatment. The distribution of FcgammaRIIIB genotypes significantly differed between responders and non-responders after 8 weeks (P < 0.05). CONCLUSIONS FcgammaRIIIB polymorphisms may be an important factor for clinical response to IFX treatment in CD.