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Updated: Jun 26, 2026
Analysis of Simian Immunodeficiency Virus-specific CD8+ T-cells in Rhesus Macaques by Peptide-MHC-I Tetramer Staining
Published on: December 23, 2016
Differential pathogenicity of SHIV infection in pig-tailed and rhesus macaques
Patricia Polacino1, Kay Larsen, Lindsey Galmin
1Washington National Primate Research Center, University of Washington, Seattle, WA, USA.
Background:
Differential pathogenicity has been observed in cynomolgus and rhesus macaques following primate lentivirus infection. However, little is known about the comparative susceptibility of pig-tailed macaques to lentivirus infection and diseases.
Methods:
We compared the in vivo infectivity and pathogenicity of a CCR5-tropic SHIV(SF162 P4) after intravenous, intravaginal or intrarectal inoculation in rhesus and pig-tailed macaques. Plasma viral load, peripheral blood CD4(+) T cell counts and clinical signs were monitored.
Results:
Both rhesus and pig-tailed macaques are similarly susceptible to SHIV(SF162 P4) infection by intravenous and mucosal routes. However, infection was significantly more robust in pig-tailed macaques than in rhesus, resulting in persistent viremia in 9/21 pig-tails vs. 2/24 rhesus (P < 0.013) and severe CD4(+) T-cell depletion in 2/21 pig-tails (vs. none in rhesus).
Conclusions:
Together with earlier observations, our findings underscore the importance of considering host genetic and immunological factors when comparing vaccine efficacy in different macaque species.
Insights
Pig-tailed macaques are as susceptible as rhesus macaques to simian-human immunodeficiency virus (SHIV) infection. However, pig-tailed macaques experience more severe disease, including persistent viremia and CD4(+) T-cell depletion.
Area of Science:
- Primate lentiviral research
- Immunology
- Comparative pathology
Background:
- Primate lentivirus infections exhibit varied pathogenicity in different macaque species.
- Limited data exists on pig-tailed macaque susceptibility to lentivirus and associated diseases.
Purpose of the Study:
- To compare the susceptibility and pathogenicity of simian-human immunodeficiency virus (SHIV) in pig-tailed macaques versus rhesus macaques.
- To evaluate infectivity via intravenous, intravaginal, and intrarectal routes.
Main Methods:
- Intravenous, intravaginal, and intrarectal inoculation of pig-tailed and rhesus macaques with CCR5-tropic SHIV(SF162 P4).
- Monitoring of plasma viral load, peripheral blood CD4(+) T cell counts, and clinical signs.
Main Results:
- Both macaque species showed similar susceptibility to SHIV(SF162 P4) infection via all tested routes.
- Pig-tailed macaques exhibited significantly more robust infections, with persistent viremia in 9/21 compared to 2/24 rhesus macaques.
- Severe CD4(+) T-cell depletion occurred in 2/21 pig-tailed macaques, while none were observed in rhesus macaques.
Conclusions:
- Host genetic and immunological factors are crucial when assessing vaccine efficacy across different macaque species.
- Pig-tailed macaques are a valuable model for studying lentiviral pathogenesis due to their heightened susceptibility and disease progression.
