Membrane fusion between retroviral particles: Host-range extension and vaccine prospects

We have analyzed if different populations of retroviral particles carrying the viral and cellular receptors of membrane viruses, respectively, are abl e to specifically fuse with each other. Using the glycoprotein of human imm unodeficiency virus type 1 and its cellular receptor complex, we demonstrat e that interviral membrane fusion can, indeed, occur and that the resultant fused viral structures are able to infect cells and transduce a marker gen e. On the one hand, these results have relevance for the development of vac cine strategies based on fusion-induced conformational epitopes on the vira l glycoprotein. However, in addition to this potential practical applicatio n, the results obtained (which were extended to include analyses with the v esicular stomatitis virus G protein and its cellular receptor) have far-rea ching implications for in vivo situations in which simultaneous infections with different membrane viruses can occur. (C) 2000 Academic Press.