Endothelial cell compatibility of glycopeptide antibiotics for intravenous use

The use of human venous endothelial cells for testing antibiotic solutions for intravenous compatibility provides a valuable alternative to animal models. In order to evaluate the effect of vancomycin and teicoplanin on the viability of human umbilical venous endothelial cells, intracellular ATP levels were measured by a luciferin-luciferase assay. Prostacyclin (PGI2) and thromboxane A2 (TXA2) were determined by direct radioimmunoassay. Vancomycin at concentrations of 5 and 10 mg/mL reduced the intracellular ATP content by 18.7% and 69.9%, respectively, within 60 min. In contrast, cellular energy charge remained significantly higher after incubation with teicoplanin at 5 and 10 mg/mL (reduction 8.7% and 15.5%, respectively). Neither vancomycin nor teicoplanin at a concentration of 2 mg/mL led to significant ATP decline. However, endothelial cells incubated with vancomycin resulted in significantly lower release of PGI2 and TXA2 compared with teicoplanin. These results show that teicoplanin is more compatible with endothelial cells than vancomycin, and that both antibiotics are well tolerated if diluted to a final concentration of 2 mg/mL.