Several steps of viral replication, including assembly and budding, differ between macrophages and T cells; it is likely that cell-specific host factors mediate these differences. Anx2, a calcium-dependent membrane-binding protein that can aggregate phospholipid-containing lipid rafts, is expressed to high levels in macrophages, but not in T lymphocytes or the T cell line.
Here, we use bimolecular fluorescence complementation in the T cell model to demonstrate that Anx2 and HIV-1 Gag interact at the phosphatidylinositol 4,5 bisphosphate-containing lipid raft membrane domains at which Gag mediates viral assembly. These data provide new evidence that Anx2, by interacting with Gag at the membranes that support viral assembly, functions in the late stages of HIV-1 replication. Editor: Cheryl A.
This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing interests: The authors have declared that no competing interests exist.
Though neuronal death and damage are a hallmark of the pathology associated with HAD, neurons themselves are not infected. Instead, monocyte-derived macrophages MDMs and parenchymal microglia are the productively infected cells within the brain [2] , [3] , and it is the viral proteins and inflammatory mediators released by these cells that damage neurons either directly or by causing glial dysfunction reviewed in [2] , [4].
Moreover, as HIV enters the brain within weeks after initial infection and potentially years before neurological symptoms develop [5] , [6] , it is likely that brain macrophages serve as long-lived viral reservoirs in the immunologically and pharmacologically protected central nervous system CNS [7].
