Abstract
In a previous report, it was shown that cuprophan membrane induced hemodialysis leukopenia and activated the complement system, while PMMA membrane did not.
In this study, we designed experiments to clarify the correlation between hemodialysis leukopenia and complement activation by EVAL (ethylene vinyl alcohol copolymer) and the effects of heparin, which is known to inhibit complement activation, on leukopenia and complement activation.
EVAL membrane activated the complement system via the alternative pathway, but the ability was about half of that of cuprophan membrane. While cuprophan membrane induced severe leukopenia, EVAL membrane induced only mild leukopenia. There was no significant difference in the degree of leukopenia between heparin hemodialysis and heparin-free hemodialysis with EVAL membrane. When EVAL membrane was incubated with human serum containing various amounts of heparin, the complement activation by the membrane was dose-dependently inhibited, but 1u/ml of heparin was not effective to prevent the complement activation.
These studies suggest that hemodialysis leukopenia is more closely dependent on the ability of the dialyzer membrane to activate the alternative pathway of the complement system and that the amount of heparin used in regular hemodialysis is not effective to prevent complement activation and leukopenia by EVAL membane.
