Human immunodeficiency virus type 1 variants with increased replicative capacity develop during the asymptomatic...

Area of Science:

• Virology
• Immunology
• Pathogenesis

Background:

• Human immunodeficiency virus type 1 (HIV-1) infection progresses from seroconversion to AIDS over years.
• Understanding viral evolution and replication dynamics is crucial for HIV-1 pathogenesis research.

Purpose of the Study:

• To investigate the replicative properties of sequential HIV-1 isolates and clones from an individual progressing to AIDS.
• To determine how viral replication kinetics change during HIV-1 infection and correlate with disease progression.

Main Methods:

• Sequential isolation and biological cloning of HIV-1 from patient samples.
• Evaluation of viral replication in primary macrophages and CD4+ T lymphocytes.
• Assessment of syncytium-inducing (SI) and non-syncytium-inducing (NSI) phenotypes.
• PCR assays to analyze early viral life cycle stages (entry, reverse transcription).

Main Results:

• Early HIV-1 isolates were slow-replicating and NSI.
• NSI variants with increased replication in macrophages emerged during asymptomatic infection.
• Rapidly replicating SI and NSI variants appeared later, with enhanced replication in both macrophages and CD4+ T lymphocytes.
• No inherent block in entry or reverse transcription was found for slow-replicating variants.

Conclusions:

• Rapidly replicating HIV-1 variants emerge during the asymptomatic period.
• These variants may contribute significantly to HIV-1 pathogenesis and disease progression.
• Viral evolution in replication capacity is a key factor in the clinical course of HIV-1 infection.