Glycosphingolipids and virus-cell fusion: current data highlighting the role of membrane microdomains in the HIV-1 infection cycle

Since several years we have been studying the molecular mechanisms involved in the fusion between the human immunodeficiency virus (HIV) and the plasm a membrane of target cells. We have contributed to demonstrate the essentia l role played by glycosphingolipid microdomains during the virus-cell fusio n process. In particular, we have been able to reconstitute a functional fu sion complex involving: i) a monomolecular film of glycosphingolipid mimick ing a plasma membrane microdomain, ii) the CD4 receptor, and the HIV-I surf ace envelope glycoprotein gp120. The kinetics of the molecular interactions occuring in this fusion complex were measured with a microtensiometer. Thi s experimental design would allow the evaluation of potential fusion inhibi tors such as synthetic analogs of glycosphingolipids.