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Conformational Evaluation of HIV-1 Trimeric Envelope Glycoproteins Using a Cell-based ELISA Assay
Published on: September 14, 2014
Complement activation by human monoclonal antibodies to human immunodeficiency virus
G T Spear1, D M Takefman, B L Sullivan
1Department of Immunology/Microbiology, Rush Medical School, Chicago, Illinois 60612.
Journal of Virology
|January 1, 1993
Summary
Human monoclonal antibodies targeting the V3 region of HIV gp120 effectively activate complement, leading to virolysis and C3 deposition. Soluble CD4 treatment reveals gp41 epitopes, enhancing these complement-mediated effects.
Area of Science:
- Immunology
- Virology
- Complement System
Background:
- Polyclonal antibodies from HIV-infected individuals can neutralize HIV via complement-mediated virolysis.
- The role of specific human monoclonal antibodies in complement activation against HIV is not fully understood.
Purpose of the Study:
- To investigate the ability of human monoclonal antibodies to HIV to activate complement.
- To identify HIV envelope determinants targeted by antibody-dependent complement-mediated effects.
Main Methods:
- Testing 16 human monoclonal antibodies against HIV for complement activation.
- Assessing C3 deposition on infected cells and virolysis of free virus.
- Evaluating the impact of soluble CD4 treatment on antibody-mediated effects.
Main Results:
- Monoclonal antibodies targeting the V3 region of HIV gp120 induced C3 deposition and virolysis.
- Anti-V3 antibodies were most effective against HIVMN and HIVIIIB isolates.
- Soluble CD4 treatment enhanced anti-gp41 effects but reduced anti-V3 effects.
- Virolysis was a more sensitive indicator of complement-mediated effects than C3 deposition.
Conclusions:
- Human monoclonal antibodies to the V3 region of gp120 are potent inducers of HIV virolysis and C3 deposition.
- Soluble CD4 exposes gp41 epitopes, leading to antibody binding and complement-mediated effects.
- This study provides a model system for studying complement interactions with HIV.
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