[Determination of C3a and C5a in hemapheresis procedures]

Study of the interface between blood and artificial surfaces reveals numerous undesirable reactions. For example, the formation of biologically active peptides, C3a and C5a (anaphylatoxins), is a result of complement activation via the alternative pathway. It cannot be denied that the reinjection of large quantities of these molecules could be at the origin of serious side effects. We report herein the anaphylatoxin levels found with 9 hemapheresis procedures (4 plasma filtration membranes, 3 systems for platelet collection, 2 plasma treatment techniques (dextran sulfate cellulose column and cascade filtration)). All the filtration procedures generated very high levels of anaphylatoxins, especially C3a. In contrast, the centrifugation systems produced lower levels. However, considerable amounts of C3a were found with the Cobe Spectra and V50 Haemonetics blood cell separators. The anaphylatoxins generated by the primary filter were partially retained by the dextran sulfate column. These high toxin levels enable an assessment of the degree of hemo-incompatibility of these systems. However, it remains difficult to evaluate whether these anaphylatoxins are dangerous or not.