Detergent Sclerosants are Deactivated and Consumed by Circulating Blood Cells

Objective To investigate the deactivating effects of circulating blood cells on the lytic activity of detergent sclerosants. Methods Samples of whole blood (WB), platelet-rich plasma (PRP), and isolated leukocytes were incubated with various concentrations of sodium tetradecyl sulfate (STS) or polidocanol (POL) and added to human umbilical vein endothelial cells (HUVECs), which were then counted using a fluorescent plate reader. Full blood counting was performed using a hematology analyzer. Platelet lysis and microparticle formation was assessed using lactadherin binding in flow cytometry. Results Detergent sclerosant activity was decreased in WB when compared with plasma and saline controls. The sclerosant lytic activity on endothelial cells was increased 23-fold for STS and 59-fold for POL in saline controls compared with WB. At high concentrations, sclerosants lysed erythrocytes, leukocytes, and platelets. Platelets were more sensitive to the lytic activity of sclerosants than other cell types. Neutrophils were the most susceptible of all leukocytes to the lytic activity of sclerosants. The presence of erythrocytes and leukocytes in samples decreased the lytic activity of sclerosants. Sclerosants at all concentrations induced erythrocyte-derived microparticle formation. Conclusions Detergent sclerosants are consumed and deactivated by circulating blood cells. This deactivating effect is above and beyond the neutralizing effects of plasma proteins and contributes to the overall neutralizing effect of blood. Different blood cell types exhibited varying levels of vulnerability to the lytic activity of sclerosants with platelets being the most and erythrocytes the least vulnerable (platelets > leukocytes > erythrocytes).