Liposomes and influenza viruses as an in vitro model for membrane interactions II. Influence of vesicle size and preparation methods

Abstract

As previously demonstrated, membrane fusion and transfer of prodrug-type molecules between membranes can be studied with the octadecylrhodamine B chloride (R18) marker. We use this assay with PR8 influenza viruses and small (SUV) or large (LUV) unilamellar liposomes containing the virus receptor G D1a as interacting partners in order to analyse the effect of membrane curvature on fusion and transfer. Computer analysis revelaed no difference in the kinetics of fusion between PR8 with large or small liposomes respectively. Lipid transfer, however, is about 5 to 6 times faster from SUV than from LUV. We also tested the influence of the production method for liposomes, namely detergent dialysis, sonication and extrusion on membrane interactions. Fusion is not affected by either, whereas transfer is slower with liposomes produced by sonication.