Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

Recent studies provide compelling evidence that HIV-1 entry in cell lines and lymphocytes proceeds by endocytosis, but these studies are still lacking in macrophages, an important natural target cell for HIV-1. Macrophages exhibit continual and extensive endocytic activity as part of their natural functions, so we investigated the uptake pathways involved in productive HIV-1 entry. We find that caveolae are not utilised by HIV-1, because the main structural proteins, caveolin-1 and 2 are absent from most human leukocytes. We then focused on macropinocytosis; we find that HIV-1 entry into macrophages is sensitive to inhibitors of Na(+)/H(+) exchange, actin rearrangement, dynamin, Rho family GTPases, and Pak1, but not to inhibitors of PI-3 kinase and myosin II. This leads us to conclude that HIV entry into macrophages proceeds by an endocytic pathway that is not classical macropinocytosis. Because of the limitations of a purely pharmacological study such as this, the final elucidation of this pathway awaits the development of reliable forward genetic approaches in authentic macrophages.

Original publication




Journal article



Publication Date





234 - 250


Cells, Cultured, Dynamins, Endocytosis, HIV-1, Humans, Macrophages, Virus Internalization, p21-Activated Kinases, rac1 GTP-Binding Protein