SIGNIFICANT REDUCTION OF FACTOR-D AND IMMUNOSUPPRESSIVE COMPLEMENT FRAGMENT BA BY HEMOFILTRATION

Because of their effect on the immune response, especially in patients with chronic or acute renal failure, factor D (FD) and the immunosupp ressive complement fragment Ba are substances which may be important f or the immunological status. Since they cannot be eliminated by conven tional Cuprophan hemodialysis because of their high molecular weight ( 24,000 and 33,000 D, respectively), the effect of hemofiltration (HF) on the plasma concentration of both components was tested. It was show n that plasma levels of FD can be lowered by 43.5% during an HF treatm ent and the plasma concentration of Ba by 30.6%. Moreover, the two sub stances could be detected in the hemofiltrate. Up to 75 mg FD and up t o 37 mg Ba could be eliminated per treatment, depending on the plasma concentrations and the filtration volume. A convective method such as chronic HF is therefore clearly superior to diffusive methods of blood purification when substances with such a high molecular weight have t o be eliminated. It has still to be established whether the eliminatio n of FD and Ba by chronic intermittent HF results in a sustained impro vement in the immunological status of patients treated in this way.