PERSISTENT REDUCTION OF COMPLEMENT RECEPTOR-3 ALPHA-CHAIN EXPRESSING MONONUCLEAR BLOOD-CELLS AND TRANSIENT INHIBITORY SERUM FACTORS IN WHIPPLES-DISEASE

Several small studies have indicated an impaired cell mediated immune response as a possible cause for the delayed elimination of the bacter ia in Whipple's disease. A specific defect, however, has not been defi ned. We examined the expression of cell surface molecules and mitogeni c responses of peripheral blood mononuclear cells in 27 patients with Whipple's disease at different disease stages by indirect immunofluore scence and by measurement of [H-3]thymidine incorporation, respectivel y. E-rosette formation and cutaneous reaction to seven recall antigens were determined. Matched healthy donors served as controls. We found a significantly reduced number of cells expressing the complement rece ptor 3 alpha-chain (=CD11b) in all patients. In florid disease, the nu mber of activated cells (in particular CD58 positive cells) was increa sed and CD4/CD8 ratios were diminished. Proliferation to phytohemagglu tinin and to sheep red blood cells was reduced at all stages of the di sease. Serum of control persons reversed this decreased responsiveness especially in patients with active disease. Skin reaction was hypoerg ic in all patients. Determination of CD58 positive cells increased in patients with active disease may be useful to define the activity of t he disease and the duration necessary for treatment. Transient inhibit ing serum activities may impair the CD2/CD58 interaction. The reductio n of cells expressing CD11b, the decreased proliferation, and the cuta neous hypoergy indicate a persisting defect of cell mediated immunity in vivo and in vitro. These defects may contribute to the impaired abi lity of patients with Whipple's disease to eliminate bacteria. (C) 199 4 Academic Press, Inc.