Abstract
Recombinant human tumor necrosis factor-β (rhTNF-β) may be encapsulated with high efficiency in phosphatidylcholine and distearoylphosphatidylcholine liposomes, with entrapment values of 93.4% and 92.3%, respectively, by first entrapping the substance in multilamellar vesicles using a high solute-to-phospholipid ratio followed by freeze-drying and then rehydration. The entrapped cytokine retains potent cytotoxic activity on L929 cells in vitro, causing 100% cytotoxicity, equal to that of free rhTNF-β at a concentration of about 5 × 10-8 g/ml.