HIV interaction with endosomes in macrophages and dendritic cells

Herpes Simplex Virus Type 1 Cytoplasmic Envelopment Requires Functional Vps4

“…In summary, it appears that the ESCRT pathway provides the budding machinery for a wide variety of enveloped viruses, which we suggest include HSV-1, where the interactions of a large number of virus-specific proteins are involved in assembly and envelopment. In some cases, budding of viruses has been observed at MVEs, the normal sites of action of the ESCRT machinery (9,19), but in other cases it is clear that viruses can recruit ESCRT components to alternative compartments, such as the plasma membrane (20). In the case of herpes simplex virus it is apparent that the budding compartment lacks the morphological characteristics of MVEs, but the precise nature of the compartment remains unknown.…”

Productive Human Immunodeficiency Virus Type 1 Assembly Takes Place at the Plasma Membrane

“…While these findings suggest that HIV particles accumulating in LE/MVB do not significantly contribute to the overall virus released extracellularly from HEK 293T cells, they do not preclude that in other cell types such as macrophages or dendritic cells and under some physiological stimulus (e.g., antigen presentation or calcium influx, which induce endosome fusion with the cell surface), virus internalized in LE/MVB is eventually released in the extracellular milieu or transmitted upon contact between cells during formation of an immunological synapse. Indeed, it was previously reported that virus accumulating intracellularly in macrophages remains infectious (26,52) and can efficiently be transmitted to T cells for extended periods of time (52). More recently, under conditions mimicking antigen recognition by interacting T cells, dendritic cells were shown to transmit captured virions from internal compartments.…”

In macrophages, HIV-1 assembles into an intracellular plasma membrane domain containing the tetraspanins CD81, CD9, and CD53

“…Immunolabeling indicates that the intracellular sites of assembly in these cells are enriched in major histocompatibility complex class II (MHC-II) molecules, suggesting that they are MHC-II compartments (MIICs) where MHC-II molecules acquire their peptide cargo (Raposo et al, 2002). In support of this view, the intracellular virus-containing compartments (VCCs) also label for some markers of late endosomes, such as the tetraspanin CD63 (Raposo et al, 2002;Pelchen-Matthews et al, 2003;Kramer et al, 2005). Several studies with T cells, or cell lines such as HeLa, COS, or HEK293, have also demonstrated a limited and/ or transient association of assembling HIV, or of Gag-based viruslike particles, with CD63-containing late endosomes (Nydegger et al, 2003;Sherer et al, 2003;Grigorov et al, 2006;Perlman and Resh, 2006), suggesting an association between HIV assembly and late endosomes in most cells (Resh, 2005).…”