LEUKOCYTES CELL-SURFACE RECEPTOR MOLECULE S CD11B, CD11C, CD35 AND HEMODIALYSIS ASSOCIATED LEUKOPENIA

Transient leukopenia and complement activation are well documented in hemodialysis (HD). To elucidate the mechanisms involved in these proce sses the expression of adhesion receptor molecules was investigated on neutrophils (PMN) and monocytes in 26 patients dialysed with differen t dialyzer membrane materials. Blood was obtained from dialyzer inlets and outlets for determination of C3a/C5a desArg by ELISA and expressi on of integrins CD11b (CR3), CD11c (CR4) and complement receptor CD35 (CR1) by flow cytometry. Expression of all three receptors was found s ignificantly upregulated in PMN and monocytes occurring rapidly after start of HD and correlating with maximal neutropenia and complement ac tivation. Our results demonstrate that leukopenia and complement activ ation are associated with an upregulation of cell surface receptor mol ecules. These adhesion proteins could be involved in leukocyte aggrega tion, and adherence to endothelia or foreign surfaces.