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Imaging of HIV-1 Envelope-induced Virological Synapse and Signaling on Synthetic Lipid Bilayers
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Different requirements for membrane fusion mediated by the envelopes of human immunodeficiency virus types 1 and 2

T Dragic1, M Alizon

  • 1Institut National de la Santé et de la Recherche Médicale U332, Institut Cochin de Génétique Moléculaire, Paris, France.

Journal of Virology
|April 1, 1993
PubMed

Insights

Human immunodeficiency virus type 1 (HIV-1) cannot infect U87MG and SCL1 cells. This suggests specific cellular factors are needed for HIV-1 fusion, which differ from those required for HIV-2 infection.

Area of Science:

  • Virology
  • Cell Biology
  • Immunology

Background:

  • CD4+ cells are crucial targets for human immunodeficiency viruses.
  • Previous studies have focused on CD4 receptor interactions for viral entry.
  • The specific cellular factors governing membrane fusion remain incompletely understood.

Purpose of the Study:

  • To investigate the permissiveness of U87MG and SCL1 cell lines to human immunodeficiency virus type 1 (HIV-1) infection.
  • To identify cellular factors involved in HIV-1 mediated cell fusion.
  • To compare the cellular requirements for fusion mediated by HIV-1 and HIV-2.

Main Methods:

  • Utilized human cell lines U87MG and SCL1 expressing CD4.
  • Attempted infection with HIV-1 and fusion with HIV-1 envelope-expressing cells.
  • Created heterokaryons with HeLa cells to assess complementation of fusion block.
  • Compared permissiveness to HIV-1 and HIV-2.

Main Results:

  • U87MG and SCL1 CD4+ cells demonstrated resistance to HIV-1 infection and fusion.
  • Complementation of the fusion block was observed in heterokaryons with HeLa cells.
  • U87MG cells expressing CD4 were permissive to HIV-2, indicating differential cellular requirements.

Conclusions:

  • The resistance of U87MG and SCL1 cells to HIV-1 is likely due to the absence of essential cellular factors for membrane fusion.
  • Distinct cellular factors may mediate fusion for HIV-1 and HIV-2, highlighting differences between these related retroviruses.

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