Influence of teicoplanin and vancomycin on degranulation by polymorphonuclear leucocytes stimulated by various agonists: an in-vitro study.

The interaction between vancomycin and teicoplanin (50 and 100 mg/l) on human neutrophils was studied using fMLP- and A23187-induced degranulation of elastase, beta-glucuronidase and vitamin B12-binding-protein. Each of these proteins is a marker of a different population of granules. fMLP-induced degranulation of beta-glucuronidase was significantly impaired by pre-incubating the neutrophils with teicoplanin (without affecting cell viability) although the inhibition was at most 23% at 100 mg/l, a concentration not achieved in the serum of patients after normal doses. Calcium ionophore-induced degranulation of beta-glucuronidase and elastase were slightly impaired (Student two-tailed; P less than 0.1) by both glycopeptides (beta-glucuronidase) and teicoplanin only (elastase). Again, inhibition remained below 25%. Vancomycin and teicoplanin at high concentrations, seldom achieved in patients, can moderately impair neutrophil degranulation.