Cell surface antigens expressed on polymorphonuclear cells in the peripheral blood from patients with inflammatory rheumatic diseases: two-color flow-cytometric analysis.

Cell surface antigens, such as CR3, Fc gamma RIII, cALLa and Leu 8 antigen, expressed on polymorphonuclear cells (PMN) in the peripheral blood (PB) are associated with certain functions of PMN. Functional alterations of PMN have been reported in some rheumatic diseases. In this study, therefore, the cell surface antigens were examined by 2-color flow-cytometry using monoclonal antibodies to clarify whether expressions of the antigens on PMN are abnormal in patients with rheumatic diseases including Behçet's disease (BD), rheumatoid arthritis (RA) and Sjögren's syndrome (SS). We found that expressions of CR3 and cALLa were increased on PB-PMN from patients with BD or RA, but not from those with SS. In BD, we further determined the phagocytic activity of PMN by a flow-cytometric method using fluorescent particles. The phagocytic activity was significantly higher in BD patients than in healthy controls, and correlated slightly with the expression of CR3 on PMN in the patients. In addition, prednisolone or colchicine seemed to decrease the expression of CR3 and/or cALLa in patients. The above results indicated that PB-PMN in BD and RA, but not SS, are phenotypically activated in vivo, and the activation probably reflects several cytokines and/or other stimuli to PMN produced in the inflammatory process.