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Updated: Aug 6, 2026
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Analysis of Simian Immunodeficiency Virus-specific CD8+ T-cells in Rhesus Macaques by Peptide-MHC-I Tetramer Staining
Published on: December 23, 2016
Simian immunodeficiency viruses replication dynamics in African non-human primate hosts: common patterns and
Ivona Pandrea1, Guido Silvestri, Richard Onanga
1Tulane National Primate Research Center, Covington, LA 70433, USA. ipandrea@tulane.edu
Journal of Medical Primatology
|July 29, 2006
Summary
Simian immunodeficiency virus (SIV) infections show a common replication pattern across different primate hosts. Host immune responses, not viral characteristics, determine disease outcome in SIV infection.
Area of Science:
- Primate Virology
- Immunodeficiency Virus Research
- Comparative Pathology
Background:
- Simian immunodeficiency virus (SIV) causes infections in various primate species, with differing clinical outcomes.
- Understanding SIV replication dynamics is crucial for insights into lentiviral pathogenesis and host-virus interactions.
Purpose of the Study:
- To identify common features of SIV replication across different naturally infected host species.
- To compare viral replication dynamics in experimentally infected African green monkeys, mandrills, and sooty mangabeys.
Main Methods:
- Experimental infection of 31 African green monkeys (AGMs), 14 mandrills, and 3 sooty mangabeys (SMs) with species-specific SIV strains.
- Monitoring of viral loads (VLs) post-infection to assess replication dynamics.
- Analysis of viral genome structure and co-receptor usage in relation to replication levels.
Main Results:
- Rapid SIV replication observed, reaching high viral loads (10^5-10^9 copies/ml) within 9-14 days post-infection.
- Set point viremia established by 42-60 days post-infection, with higher levels in SMs and mandrills compared to AGMs.
- Viral replication levels did not correlate with viral genome structure but were dependent on the SIV strain and host species.
Conclusions:
- A common pattern of SIV replication exists in naturally and experimentally infected hosts, similar to pathogenic SIV infections in macaques.
- Differences in clinical outcomes between pathogenic and non-pathogenic SIV infections are primarily determined by host responses.
- Host immune responses play a critical role in modulating the outcome of SIV infections, irrespective of viral characteristics.
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