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A Restriction Enzyme Based Cloning Method to Assess the In vitro Replication Capacity of HIV-1 Subtype C Gag-MJ4 Chimeric Viruses
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A Restriction Enzyme Based Cloning Method to Assess the In vitro Replication Capacity of HIV-1 Subtype C Gag-MJ4 Chimeric Viruses

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Per-pathogen virulence of HIV-1 subtypes A, C and D

Judith A Bouman1, Colin M Venner2, Courtney Walker2

  • 1Institute of Integrative Biology, ETH Zurich, 8092 Zurich, Switzerland.

Proceedings. Biological Sciences
|May 10, 2023
PubMed

Insights

HIV-1 subtype C shows higher virulence than subtype A, potentially explaining its faster spread. This research uses clinical data to estimate virulence and transmission speed differences among subtypes.

Area of Science:

  • Virology
  • Epidemiology
  • Immunology

Background:

  • Human Immunodeficiency Virus type 1 (HIV-1) subtypes exhibit varying clinical outcomes and transmission rates.
  • Subtype C is increasingly prevalent compared to subtypes A and D.
  • Understanding subtype-specific virulence is crucial for predicting disease spread.

Purpose of the Study:

  • To investigate differences in per-pathogen virulence among HIV-1 subtypes A, C, and D.
  • To determine if virulence differences explain the varying spread rates of these subtypes.
  • To explore the relationship between virulence, viral load, and subtype.

Main Methods:

  • Utilized data from a study on hormonal contraception, HIV-1 shedding, and disease progression in women with primary HIV infection.
  • Determined set-point viral load, CD4+ T cell levels, and CD4+ T cell decline post-primary infection.
  • Estimated time until Acquired Immunodeficiency Syndrome (AIDS) and calculated virulence as the inverse of this time.

Main Results:

  • Subtype C demonstrated significantly higher per-pathogen virulence compared to subtype A.
  • A model was fitted to assess virulence and set-point viral load, testing for subtype-specific variations.
  • The relationship between virulence and viral load was found to vary across subtypes.

Conclusions:

  • HIV-1 subtype C possesses greater per-pathogen virulence than subtype A.
  • Differences in the primary infection period length are hypothesized to drive observed variations in subtype spread rates.
  • Virulence differences among HIV-1 subtypes are a key factor in their epidemiological dynamics.

Keywords:
HIV-1disease progressionper-pathogen pathogenicityset-point viral loadsubtypesvirulence

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