The downregulation of CD4 and MHC‐I by primate lentiviruses: a paradigm for the modulation of cell surface receptors

@article{Piguet1999TheDO,
  title={The downregulation of CD4 and MHC‐I by primate lentiviruses: a paradigm for the modulation of cell surface receptors},
  author={Vincent Piguet and Olivier Schwartz and Sylvie Le Gall and Didier Trono},
  journal={Immunological Reviews},
  year={1999},
  volume={168}
}
Summary: The human and simian immunodeficiency viruses (HIV and SIV) downregulate the cell surface expression of CD4. their primary receptor, and of class I histocompatibility complex (MHC‐I), a critical mediator of immune recognition. While the first of these effects seems important to preserve viral infectivity, the second likely promotes immune evasion. Three HIV‐1 proteins, Nef, Env and Vpu, contribute Eo downregulate CD4. Env forms a complex with CD+ in the endoplasmic reticulum, thereby… 
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TLDR
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TLDR
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TLDR
It is suggested that nef-deleted or highly mutated defective HIV (dHIV) genomes interfere with replication of "wild type" HIV in certain long-term non-progressor individuals, implying that introduction of artificially constructed dHIV genomes (by infusion of leukocytes carrying dH HIV proviruses) into HIV infected individuals could slow disease progression and could be considered as a therapeutic possibility.
Cell Surface CD4 Interferes with the Infectivity of HIV-1 Particles Released from T Cells*
TLDR
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TLDR
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It is shown that the expression of MHC–I at the surface of lymphoid, monocytic and epithelial cells was reduced in the presence of Nef protein from various HIV–1 strains, representing a previously undocumented viral mechanism for evading the immune response.
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