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-α) and Fc-gamma receptor (FcγR) 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-α and FcγR 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-α, FcγRIIA, and FcγRIIIA genotypes was not significantly different between responders and non-responders 8 weeks after treatment. The distribution of FcγRIIIB genotypes significantly differed between responders and non-responders after 8 weeks (P<0.05). Conclusions: FcγRIIIB polymorphisms may be an important factor for clinical response to IFX treatment in CD.