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Updated: Jul 13, 2026
07:06
Prediction of HIV-1 Coreceptor Usage (Tropism) by Sequence Analysis using a Genotypic Approach
Published on: December 1, 2011
Baseline HIV type 1 coreceptor tropism predicts disease progression
Eric S Daar1, Karen L Kesler, Christos J Petropoulos
1Los Angeles Biomedical Research Institute at Harbor-University of California-Los Angeles (UCLA) Medical Center and the David Geffen School of Medicine at UCLA, Torrance, USA. EDaar@LABioMed.org
Summary
Human immunodeficiency virus type 1 (HIV-1) coreceptor tropism, determined by the envelope gene, significantly impacts disease progression. Detecting CXCR4-using HIV-1 at baseline predicts faster CD4+ T cell decline and increased AIDS risk.
Area of Science:
- Virology
- Immunology
- Infectious Diseases
Background:
- Human immunodeficiency virus type 1 (HIV-1) coreceptor tropism, mediated by the envelope gene, dictates viral entry via CCR5 or CXCR4.
- The influence of coreceptor tropism on HIV-1 natural history remains incompletely understood.
Purpose of the Study:
- To investigate the impact of HIV-1 coreceptor tropism on disease progression in children and adolescents.
- To determine if coreceptor tropism independently predicts clinical outcomes in HIV-1 infection.
Main Methods:
- Coreceptor tropism was assessed using a single-cycle assay on baseline plasma samples from 126 HIV-1-infected children and adolescents.
- Participants were enrolled in the Hemophilia Growth and Development Study between 1989-1990 with follow-up through 1997.
Main Results:
- Detectable CXCR4-using HIV-1 at baseline correlated with lower CD4+ T cell counts and higher viral RNA levels.
- CXCR4 tropism independently predicted a significant decrease in CD4+ T cell counts over time (P<.001).
- A 3.8-fold increased risk of clinical AIDS progression was associated with CXCR4-using virus.
Conclusions:
- Coreceptor tropism, assessed via single-cycle assay, is an independent determinant of HIV-1 disease progression.
- This finding highlights the prognostic value of tropism testing in managing HIV-1 infection.
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