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Evolution Driven By A Varying Host Environment Selects For Distinct HIV-1 Entry Phenotypes and Other Informative
Shuntai Zhou1,2, Nathan Long1, Ronald Swanstrom1,3
1Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Frontiers in Virology (Lausanne, Switzerland)
|January 19, 2024
Summary
Human immunodeficiency virus type 1 (HIV-1) diversity drives distinct viral phenotypes, impacting disease progression and treatment. Understanding these phenotypes is crucial for developing effective HIV-1 therapies and vaccines.
Area of Science:
- Virology
- Immunology
- Pathogenesis
Background:
- Human immunodeficiency virus type 1 (HIV-1) exhibits significant intra- and inter-host diversity, evolving distinct phenotypes under host selective pressures.
- Transmitted HIV-1 often displays an R5 T cell-tropic phenotype, utilizing CD4 and CCR5 for entry, but can evolve to a X4 phenotype using CXCR4.
- Macrophage-tropic (M-tropic) HIV-1, primarily using CCR5, efficiently infects cells with low CD4 density and is frequently found in the central nervous system, linked to neurological impairment.
Purpose of the Study:
- To comprehensively review HIV-1 entry, transmission, and drug resistance phenotypes.
- To understand the host environment dynamics that drive HIV-1 phenotype evolution and their impact on pathogenesis.
- To assess current and past research methodologies for characterizing HIV-1 phenotypes.
Main Methods:
- Review of existing literature on HIV-1 viral diversity, tropism, and drug resistance.
- Analysis of selective pressures including host immune responses (antibody and CD8+ T cells) and antiviral therapy.
- Evaluation of methods used to characterize HIV-1 phenotypes, such as tropism assays and resistance genotyping.
Main Results:
- HIV-1 evolves diverse phenotypes, including R5-tropic, X4-tropic, and M-tropic variants, each with implications for cellular tropism and disease progression.
- Interferon resistance and drug resistance phenotypes emerge under specific selective pressures during infection.
- Phenotypic characteristics of HIV-1 are critical determinants of treatment efficacy, clinical outcomes, and vaccine development strategies.
Conclusions:
- Understanding the evolution and characteristics of HIV-1 phenotypes is essential for advancing HIV-1 treatment, prevention, and cure strategies.
- The interplay between viral evolution and host environment dynamics significantly influences HIV-1 pathogenesis.
- Continued research into phenotype characterization methods is vital for accurate assessment and therapeutic targeting.
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