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Conformational Evaluation of HIV-1 Trimeric Envelope Glycoproteins Using a Cell-based ELISA Assay
Published on: September 14, 2014
Sequence variation occurs in CD4 epitopes during early HIV infection
Jenna Rychert1, Suzanne Saindon, Sarah Placek
1Partners AIDS Research Center, Massachusetts General Hospital, Boston, MA 02114, USA.
Journal of Acquired Immune Deficiency Syndromes (1999)
|January 3, 2008
Summary
Viral sequence variation occurs in human immunodeficiency virus (HIV)-specific CD4 epitopes during early infection. These mutations may impact T helper cell function, influencing the immune response to HIV.
Area of Science:
- Immunology
- Virology
- Molecular Biology
Background:
- Early HIV infection is characterized by rapid viral replication and immune system engagement.
- Understanding viral evolution within specific immune targets is crucial for vaccine and therapeutic development.
Purpose of the Study:
- To investigate viral sequence variation within human immunodeficiency virus (HIV)-specific CD4 epitopes during the early stages of infection.
- To correlate viral sequence changes with T-cell responses.
Main Methods:
- Sequencing of Gag, Nef, and integrase (Int) genes from plasma of 7 individuals during acute HIV-1 infection.
- Analysis of viral sequence changes between two early time points.
- Measurement of peptide-specific CD4+ T-cell responses using interferon-gamma enzyme-linked immunosorbent spot assays.
Main Results:
- An average of 4 mutations per subject were identified, predominantly nonsynonymous.
- Significant amino acid changes occurred in Gag, Nef, and Int proteins.
- Half of the observed sequence changes were located within known CD4 epitopes.
- Mutations within CD4 epitopes correlated with alterations in peptide-specific CD4 responses.
Conclusions:
- Sequence variation within recognized CD4 epitopes is a feature of early HIV infection.
- Mutations in these critical epitopes may modulate T helper cell function and the adaptive immune response to HIV.
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