No abstract

No abstract

No abstract

No abstract

Endogenous platelet factor 4 released from blood platelets is capable of neutralizing both heparin and enoxaparin (ENOX). The purpose of this study is to investigate the differences in the neutralization profile of heparin and ENOX preparations by PF4. Citrated whole blood was centrifuged to obtain platelet rich (PRP) and platelet poor (PPP) plasma. Both were supplemented with three batches of heparin, generic enoxaparin (GENOX) and branded enoxaparin in a concentration of 0–10 ug/ml. Clot based, APTT, Heptest, Thrombin time and amidolytic anti‐Xa and IIa were measured. The anticoagulant responses in the aPTT, Heptest and TT were found to be markedly reduced in the PRP samples, >;70% neutralization was observed in these assays. Similarly in the anti‐Xa and IIa assays, PRP samples showed a reduction in the inhibitory effects, which were >;50% in both assays. The GENOX and ENOX exhibited a lesser neutralization effect in the APTT and Heptest assays in comparison to the heparin. The neutralization profile ranged 20–30% in the clot based assays. In the amidolytic assays, the anti‐IIa activity was more efficiently neutralized. The mean neutralization was >;70% for the anti‐IIa. In the anti‐Xa assay, the GENOX's showed less neutralization (ranging from 20–30%). These results suggest that endogenous platelet factor 4 is capable of differentially neutralizing both the heparin and ENOX in an assay dependent fashion.