1. Tokyo Joint Laboratory and Division of International Collaboration Research, Joint Research Center for Human Retrovirus Infection, Kumamoto University, Kumamoto, Tokyo, Japan
2. Center for AIDS Research, Kumamoto University, Kumamoto, Japan
3. National Hospital of Tropical Diseases, Hanoi, Vietnam
4. Hanoi Medical University, Hanoi, Vietnam
5. AIDS Clinical Center, National Center for Global Health and Medicine, Tokyo, Japan