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Published in:

01-03-2012 | The Science of HIV (AL Landay, Section Editor)

The HIV-1 Env Protein: A Coat of Many Colors

Authors: Kathryn Twigg Arrildt, Sarah Beth Joseph, Ronald Swanstrom

Published in: Current HIV/AIDS Reports | Issue 1/2012

Abstract

HIV-1 is completely dependent upon the Env protein to enter cells. The virus typically replicates in activated CD4+ T cells due to viral entry requirements for the CCR5 coreceptor and for high surface levels of the CD4 receptor. This is the case for the transmitted virus and for most of the virus sampled in the blood. Over the course of infection, the env gene can evolve to encode a protein with altered receptor and coreceptor usage allowing the virus to enter alternative host cells. In about 50% of HIV-1 infections, the viral population undergoes coreceptor switching, usually late in disease, allowing the virus to use CXCR4 to enter a different subset of CD4+ T cells. Neurocognitive disorders occur in about 10% of infections, also usually late in disease, but caused (ultimately) by viral replication in the brain either in CD4+ T cells or macrophage and/or microglia. Expanded host range is significantly intertwined with pathogenesis. Identification and characterization of such HIV-1 variants may be useful for early detection which would allow intervention to reduce viral pathogenesis in these alternative cell types.

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Title: The HIV-1 Env Protein: A Coat of Many Colors
Authors: Kathryn Twigg Arrildt
Sarah Beth Joseph
Ronald Swanstrom
Publication date: 01-03-2012
Publisher: Current Science Inc.
Published in: Current HIV/AIDS Reports / Issue 1/2012
Print ISSN: 1548-3568
Electronic ISSN: 1548-3576
DOI: https://doi.org/10.1007/s11904-011-0107-3

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