BUDESONIDE AND PREDNISOLONE SUPPRESS PERIPHERAL-BLOOD NATURAL-KILLER-CELLS IN CROHNS-DISEASE

Aim: To study the effect of oral budesonide and prednisolone on periph eral blood natural killer (NK) cell activity in patients with active i leocaecal Crohn's disease (Crohn's disease activity index, CDAI greate r than or equal to 200).Methods: One group of patients was treated for 10 weeks with oral budesonide (n = 9; 9 mg/day), and another group of patients for the same period with prednisolone (n = 9; 40 mg/day). Bu desonide was tapered to 6 mg/day after 8 weeks and prednisolone after 2 weeks to 5 mg/day in the last week. Before treatment, and at 2, 4 an d 10 weeks of treatment, natural killer cell activity was determined w ith a Cr-51 release assay, and the number of CD16(+) NK cells by Fluor esence activated cell sorter (FACS) analysis. Results: Budesonide, as well as prednisolone treatment, significantly decreased natural killer cell activity at weeks 2 and 4. This decrease was found to be accompa nied by a similar decrease in the number of CD16(+) NK cells. At 10 we eks, natural killer cell activity had almost returned to pre-treatment levels in the budesonide group and was significantly higher than pre- treatment levels in the prednisolone group. Disease activity was signi ficantly decreased in all patients at week 2 until the end of the tria l period. Conclusion: Both budesonide and prednisolone treatment suppr ess peripheral blood natural killer cell activity of patients with act ive ileocaecal Crohn's disease by decreasing the numbers of CD16(+) NK cells in the circulation.