Differential pathogenicity of SHIV infection in pig-tailed and rhesus macaques.
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.
Polacino
Patricia
P
Washington National Primate Research Center, University of Washington, Seattle, WA, USA.
Larsen
Kay
K
Galmin
Lindsey
L
Suschak
John
J
Kraft
Zane
Z
Stamatatos
Leonidas
L
Anderson
David
D
Barnett
Susan W
SW
Pal
Ranajit
R
Bost
Kristen
K
Bandivdekar
A H
AH
Miller
Christopher J
CJ
Hu
Shiu-Lok
SL
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D016130:Immunophenotyping / Q000662:veterinary; D008253:Macaca mulatta; D008254:Macaca nemestrina; D016097:Simian Acquired Immunodeficiency Syndrome / Q000821:virology*; D015302:Simian Immunodeficiency Virus / Q000472:pathogenicity*; D013045:Species Specificity; D014766:Viremia / Q000662:veterinary