Role of envelope glycoprotein carbohydrate in human immunodeficiency virus (HIV) infectivity and virus-induced cell fusion.

J Lifson,S Coutré,E Huang,E Engleman

doi:10.1084/jem.164.6.2101

Abstract

Human immunodeficiency virus (HIV) envelope glycoprotein interactions with cell surface CD4 are involved in both virion infectivity and virally mediated cell fusion. D-mannose-specific lectins such as Con A specifically blocked virion infectivity and cell fusion. Studies with a recombinant vaccinia virus containing the HIV envelope gene demonstrated that Con A-mediated inhibition of HIV-induced fusion involved lectin binding to the viral envelope glycoprotein. These results indicate the importance of envelope glycosylation in the pathobiology of HIV infection, and suggest potential mechanisms for interfering with HIV infectivity and cytopathology.

Highlights

Our results suggest that mannose-containing carbohydrate moieties on the viral envelope glycoprotein are involved, either directly or indirectly, in envelope interactions with cell surface CD4
Additional studies using a recombinant vaccinia virus system, in which the envelope glycoprotein of Human immunodeficiency virus (HIV) is expressed on the surface of infected cells in the absence of synthesis of any other HIV proteins, indicate that Con A inhibition of HIV envelope glycoprotein-mediated cell fusion involves interactions between Con A and the viral envelope glycoprotein
Human immunodeficiency virus (HIV) envelope glycoprotein interactions with cell surface CD4 are involved in both virion infectivity and virally mediated cell fusion

Summary

Methods

The CD4+ T cell lines VB (6, 7) and H9 (2) have been described in detail elsewhere. Cell lines were maintained in RPMI 1640 supplemented with 10% heatinactivated FCS and 2 mM 1-glutamine. Assays of free virus infectivity and virally induced fusion (see below) were conducted in the same medium. For use in assays of virion infectivity (see below) we used the reference isolate of LAV (1), maintained in chronically infected CEM-CCRF cells. Supernatants from these chronically infected cultures were filtered through 0.22-jum filters before use as a source of infectious virus

Results

Discussion

Conclusion