[1] Ctr Dis Control & Prevent, HIV & Retrovirol Branch, Atlanta, GA 30333 USA
[2] Ctr Dis Control & Prevent, Immunol & Diagnost Branch, Natl Ctr Infect Dis, Atlanta, GA 30333 USA
[3] US FDA, Ctr Biol Evaluat & Res, Lab Retrovirus Res, Bethesda, MD 20892 USA
[4] Univ Calif Lawrence Livermore Natl Lab, Calif Reg Primate Res Ctr, Simian Retrovirus Lab, Livermore, CA 95616 USA
[5] Univ Freiburg, Dept Virol, D-79104 Freiburg, Germany