Surface Modification of Liposomal Vaccines by Peptide Conjugation

The aim of the present work was to prepare liposomal vaccine formulation by incorporating naked plasmid DNA that can trigger humoral and cell mediated protective immunity against infection. For these cationic lipids like dimyristoyl phosphatidylcholine (DMPC), dioleyl phosphatidyl ethanolamine (DOPE), [1, 2 – dioleyloxy -3-(trimethyl ammonium propane)] (DOTAP), were taken in the ratio of 4:2:1 respectively. The liposomal formulations thus prepared were surface modified by peptide conjugation with the help of EDC and NHS. Physical characterization of liposomal formulationswas done by estimating the average size distribution, which gives an average liposomal size of 53.0nm. Concentration of peptide bound liposomes wasestimated by Lowry method which entails that bound protein concentration was 30.5 μg/ml.