Natural HIV inhibitors

Replication of HIV-1 and simian immunodeficiency virus (SIVmac) is restricted in some cell lines but the exact intracellular mechanisms that block the virus replication are unknown. Two papers in September 3 Proceedings of the National Academy of Sciences of the USA indicate that the existence of one or more saturable inhibitors prevents HIV and SIV infection by targeting the capsid of the incoming lentivirus particle.

Caroline Besnier and colleagues at University College London, UK describe a saturable block to HIV and simian immunodeficiency virus, which gives rise to multiple-hit infection kinetics. In addition, they show that African green monkey cells are able to block both HIV and simian immunodeficiency virus, and that each virus is able to saturate and abrogate the restriction of the other, suggesting the involvement of a common factor (Proc Natl Acad Sci USA 2002, 99:11920-11925).

In the second paper, Simone Cowan and...