Vitamin E-bonded cellulose membrane and hemodialysis bioincompatibility: Absence of an acute benefit on expression of leukocyte surface molecules

Dialysis with unmodified cellulose membranes is associated with such bioinc ompatibility phenomena as leukopenia, increased expression of adhesion mole cules on leukocytes, and release of reactive oxygen species. Dialysis bioco mpatibility can be improved by modifications in the structure of the cellul ose membrane to diminish leukocyte activation and/or protect against the re leased free oxygen radicals. Excebrane (Terumo Corp, Tokyo, Japan) is a vit amin E-modified cellulose membrane. In the present study, the effect of dia lysis with Excebrane membranes on granulocyte and monocyte counts; CD11b, C D11c, and CD45 expression on the surface of granulocytes; and CD14 expressi on on monocytes was evaluated and compared with low-flux polysulfone membra nes. Fifteen minutes after the start of dialysis, granulocytopenia and mono cytopenia were more pronounced with the Excebrane membrane compared with po lysulfone. The increase in basal expression of CD11b and CD45 on circulatin g granulocytes was more pronounced during dialysis with Excebrane than poly sulfone membranes. Regarding the increased expression on in vitro stimulati on with phorbol myristate acetate, blunted upregulation was obtained during dialysis using Excebrane membranes for CD11c and CD45 expression on granul ocytes and CD14 expression on monocytes. In conclusion, such indices of mem brane bioincompatibility as leukocyte counts and expression of leukocyte su rface molecules show more profound alterations with Excebrane than the stan dard low-flux polysulfone membrane in both basal and in vitro activated sta tes. (C) 2000 by the National Kidney Foundation, Inc.