C3a and C5a anaphylatoxins bind to heparin-based sorbent in low density lipoprotein apheresis: in vitro and in vivo investigations.

Plasmasorption on a heparin-based sorbent was performed in vitro. It demonstrated affinity of the C3a and C5a anaphylatoxins for the sorbent: C3a was removed almost completely (97%), and the C5a concentration decreased on average by 55%. The plasma level of C3a and C5a complement components was also monitored during the procedure of clinical extracorporeal low density lipoprotein (LDL) apheresis on the sorbent in patients with familial hypercholesterolemia. A two- to threefold increase in C3a (up to 1,500 ng/ml) was observed after plasma separation by the IBM 2997 cell sorter. Subsequent processing of the plasma through the column led to the low level of C3a detected (less than 50 ng/ml), demonstrating significant uptake of C3a by the sorbent column. The removed C3a was found in the eluate obtained after regeneration of the sorbent with 2 M NaCl solution. No significant increase in C5a was found during the procedure. Nevertheless, some C5a was detected in the eluate from the sorbent. The content of C3a and C5a in patients blood after the treatment was approximately the same as it was initially, 200-500 ng/ml for C3a and less than 10 ng/ml for C5a. The removal of C3a and C5a anaphylatoxins by heparin-based sorbent should be regarded as an advantage of this type of plasmasorbent.

[The dynamics of the concentrations of immunoglobulins and circulating immune complexes during low-density lipoprotein apheresis in patients with hereditary hypercholesterolemia]. / Dinamika kontsentratsii immunoglobulinov i tsirkuliruiushchikh immunnykh kompleksov v protsesse afereza lipoproteidov nizkoi plotnosti u bol'nykh nasledstvennoi giperkholesterinemiei.

Sessions of-low density lipoproteins (LDL) apheresis using sorbents with mono- and polyclonal antibodies possessing the most selective and specific effect with respect to LDL provoked a less marked decrease of the concentrations of immunoglobulins and circulating immune complexes. This attests to their high selectivity and specificity. Sorbents with dextran sulfate and heparin sepharose exerted a more evident influence on the concentrations of these serum components. However, that was not accompanied by any clinical manifestations of immune deficiency. The use of plasmapheresis brought about a more pronounced lowering of the concentrations of the serum components under study.