Differential expression of leukocyte functions associated antigen-1 (LFA-1) on peripheral blood mononuclear cells in patients with Crohn's disease

Background: The leukocyte function associated antigen-1 (LFA-1) intracellular adhesion molecule-1 pathway is presumed to play a pivotal role in the perpetuation of inflammatory bowel disease. We aimed to elucidate the effect of 2 different therapies on LFA-1 expression in patients with Crohn's disease (CD) and correlate LFA-1 expression with disease activity. Methods: In all, 30 patients with active CD were recruited for the present investigation. Eleven patients were treated with infliximab and 19 patients with total parenteral nutrition. The clinical activity and the expression of LFA-1 in peripheral blood mononuclear cells were assessed prior to and 4 weeks after treatment. Clinical activity was determined by measuring the Crohn's Disease Activity Index and LFA-1 expression was measured by mean fluorescence intensity (MFI) under fluorescence-activated cell sorter analysis. Results: In each treatment group the clinical disease activity index decreased significantly 4 weeks after treatment. In patients treated with infliximab, LFA-1 expression decreased significantly (mean MFI decreased from 1983 to 1487, P < 0.05). However, LFA-1 expression remained unchanged in the total parenteral nutrition group (mean MFI elevated from 1684 to 1902, P > 0.05). Conclusions: The mechanism of therapeutic action on CD is different between infliximab and total parenteral nutrition.