HIV: Cell Binding and Entry
Abstract
The first step of the human immunodeficiency virus (HIV) replication cycle—binding and entry into the host cell—plays a major role in determining viral tropism and the ability of HIV to degrade the human immune system. HIV uses a complex series of steps to deliver its genome into the host cell cytoplasm while simultaneously evading the host immune response. To infect cells, the HIV protein envelope (Env) binds to the primary cellular receptor CD4 and then to a cellular coreceptor. This sequential binding triggers fusion of the viral and host cell membranes, initiating infection. Revealing the mechanism of HIV entry has profound implications for viral tropism, transmission, pathogenesis, and therapeutic intervention. Here, we provide an overview into the mechanism of HIV entry, provide historical context to key discoveries, discuss recent advances, and speculate on future directions in the field.
ACKNOWLEDGMENTS
C.B.W., J.C.T., and R.W.D. were supported by grants T32 AI000632, F32 1F32AI077370, and R01 AI 040880, respectively. We thank Beili Wu, Ray Stevens, and Sriram Subramaniam for the use of figures and PDB (Protein Data Bank) files.
Footnotes
Editors: Frederic D. Bushman, Gary J. Nabel, and Ronald Swanstrom
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