EFFECT OF CEFAZOLIN AND VANCOMYCIN ON OSTEOBLASTS IN-VITRO

The effect of cefazolin and vancomycin on osteoblast-like cells was st udied, Cells from the MG-63 human osteosarcoma cell line were grown in antibiotic free media and exposed to concentrations of cefazolin and vancomycin at order of magnitude intervals between 0 and 10,000 mu g/m l, For cefazolin, a second interval was performed between 100 and 1000 mu g/ml to define toxic levels more accurately, Cell number and H-3-t hymidine incorporation at 0, 24, and 72 hours were determined, The res ults of this study show that local levels of vancomycin of 1000 mu g/m l and less have little or no effect on osteoblast replication, and con centrations of 10,000 mu g/ml cause cell death, Concentrations of cefa zolin of 100 mu g/ml and less have little or no effect on osteoblast r eplication, 200 mu g/ml significantly decrease cell replication, and 1 0,000 mu g/ml cause cell death, The authors conclude that vancomycin i s less toxic than is cefazolin to osteoblasts at higher concentrations and may be a better antibiotic for local administration in the treatm ent of similarly sensitive bacterial infections.