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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
Published on: August 31, 2014
Vaccination reduces simian-human immunodeficiency virus sequence reversion through enhanced viral control
Edwin R Manuel1, Wendy W Yeh, Harikrishnan Balachandran
1Division of Viral Pathogenesis, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, USA.
Journal of Virology
|October 1, 2010
Summary
Vaccination may prevent human immunodeficiency virus (HIV) reversion to wild-type. In vaccinated monkeys, challenge virus did not revert, suggesting decreased viral replication, not altered evolution.
Area of Science:
- Virology
- Immunology
- Evolutionary Biology
Background:
- Vaccination prior to human immunodeficiency virus type 1 (HIV-1) infection may attenuate the virus.
- Understanding viral evolution under immune pressure is crucial for vaccine development.
Purpose of the Study:
- To investigate if prior immunization prevents simian-human immunodeficiency virus (SHIV) reversion to wild-type.
- To explore the impact of vaccination on viral mutational evolution.
Main Methods:
- Mamu-A*01 monkeys were vaccinated to elicit a cytotoxic T-lymphocyte response to the Gag p11C epitope.
- Vaccinated and naive monkeys were challenged with a pathogenic SHIV expressing a mutant Gag p11C sequence (Δp11C SHIV).
Main Results:
- In naive monkeys, Δp11C SHIV showed attenuated replication and reverted to the wild-type Gag p11C sequence.
- In vaccinated monkeys, no reversion of the challenge virus was observed.
- Reduced viral replication in vaccinated animals may explain the absence of reversion.
Conclusions:
- Prior immunization may prevent HIV-1 reversion to wild-type by reducing viral replication.
- Viral evolution is influenced by multifactorial pressures, including immune responses.
- Findings contribute to understanding primate lentivirus evolution and vaccine strategies.
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