thromboxane-b2 and acetylcellulose

To evaluate the biocompatibility and the efficacy of leukocyte removal filters, we performed a prospective study by using the cardiopulmonary bypass perfusate taken from the heart-lung machine for 20 patients who underwent cardiac surgery and were randomly divided into four groups according to the filters used. A leukocyte removal filter was installed in the transfusion line while the perfusate was transfused to the patients. No increases of C3a, C5a, elastase, and thromboxane were found during leukocyte filtration by polyester filters (Optima, Sepacell R500, and Pall RC100). Activation of the complement cascade was observed during filtration by the cellulose acetate filter (Cellselect) although the efficacy of the Cellselect filter was evidently higher than that of the polyester filter. These results imply that polyester leukocyte filters are superior to cellulose acetate filters in terms of biocompatibility but have a reduced efficacy. An optimal leukocyte filter providing both high efficacy and biocompatibility has yet to be developed.

Topics: Biocompatible Materials; Cardiopulmonary Bypass; Cell Separation; Cellulose; Complement Activation; Complement C3a; Complement C5a; Filtration; Humans; Leukocyte Count; Leukocyte Elastase; Leukocytes; Lymphocyte Activation; Pancreatic Elastase; Platelet Count; Polyesters; Prospective Studies; Thromboxane B2

HLA alloimmunization is a major problem for thrombocytopenic patients receiving long-term platelet support. It is caused by white cells (WBCs) that are present as contaminants in platelet concentrates (PCs). Recent data have shown that filtration is an effective means to reduce WBC contamination, but it has little effect on the recovery of platelets. The present report evaluates two filters, a cellulose acetate (CA) filter requiring the inactivation of platelets with prostacyclin and a cotton wool (CW) filter requiring no platelet inactivation. The results show that, using fresh pooled PCs from six random donors, both filters reduce WBC contamination below 10(7) per PC, the likely threshold below which alloimmunization does not develop. With platelets stored for 2 to 3 days the efficacy of the CW filter decreases. Neither filter inflicts important damage to the platelets, as there is no considerable platelet activation or cell disruption. Moreover, PCs prepared by both filters show normal survival and effectively reduce the bleeding times. Thus, filtration of PCs results in platelets with optimal responsiveness both in vitro and in vivo.

Topics: Animals; Bleeding Time; Blood Platelets; Blood Transfusion; Cell Separation; Cell Survival; Cellulose; Cytoplasmic Granules; Filtration; Gossypium; Humans; Leukocyte Count; Leukocytes; Platelet Activation; Platelet Count; Platelet Transfusion; Thrombocytopenia; Thromboxane B2; Wool

Topics: Cellulose; Humans; Materials Testing; Membranes, Artificial; Platelet Factor 4; Renal Dialysis; Thromboxane B2