[1] Chiba Inst Technol, Dept Life & Environm Sci, Chiba 2750016, Japan
[2] Natl Inst Infect Dis, AIDS Res Ctr, Shinjuku Ku, Chiba 2750016, Japan
[3] Univ Ghana, Dept Virol, Noguchi Mem Inst Med Res, Legon, Accra, Ghana
[4] Japanese Fdn AIDS Prevent, Chiyoda Ku, Tokyo 10100611, Japan
[5] Tokyo Med & Dent Univ, Dept Mol Virol, Grad Sch Med, Tokyo 1138519, Japan
[6] Chiba Inst Technol, High Technol Res Ctr, Chiba 2750016, Japan