Any process in which a virus stops, prevents, or reduces the activity of host tetherin activity. Tetherin (also known as BST2) is an alpha interferon-inducible cellular factor that impairs the release of many enveloped viruses. By blocking tetherin activity, many viruses circumvent its antiviral effects.

The irregular network of unit membranes, visible only by electron microscopy, that occurs in the host cell cytoplasm of many eukaryotic cells. The membranes form a complex meshwork of tubular channels, which are often expanded into slitlike cavities called cisternae. The host ER takes two forms, rough (or granular), with ribosomes adhering to the outer surface, and smooth (with no ribosomes attached).

A compound membranous cytoplasmic organelle of eukaryotic host cells, consisting of flattened, ribosome-free vesicles arranged in a more or less regular stack.