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 bioincompatibility phenomena as leukopenia, increased expression of adhesion molecules on leukocytes, and release of reactive oxygen species. Dialysis biocompatibility can be improved by modifications in the structure of the cellulose membrane to diminish leukocyte activation and/or protect against the released free oxygen radicals. Excebrane (Terumo Corp, Tokyo, Japan) is a vitamin E-modified cellulose membrane. In the present study, the effect of dialysis with Excebrane membranes on granulocyte and monocyte counts; CD11b, CD11c, and CD45 expression on the surface of granulocytes; and CD14 expression on monocytes was evaluated and compared with low-flux polysulfone membranes. Fifteen minutes after the start of dialysis, granulocytopenia and monocytopenia were more pronounced with the Excebrane membrane compared with polysulfone. The increase in basal expression of CD11b and CD45 on circulating granulocytes was more pronounced during dialysis with Excebrane than polysulfone membranes. Regarding the increased expression on in vitro stimulation with phorbol myristate acetate, blunted upregulation was obtained during dialysis using Excebrane membranes for CD11c and CD45 expression on granulocytes and CD14 expression on monocytes. In conclusion, such indices of membrane bioincompatibility as leukocyte counts and expression of leukocyte surface molecules show more profound alterations with Excebrane than the standard low-flux polysulfone membrane in both basal and in vitro activated states.