David Ho, a renowned AIDS researcher and Time magazine's choice for 1996 Person of the Year because of his work in developing protease inhibitors, said Tuesday that it will take at least five years before two HIV vaccines developed at his Aaron Diamond AIDS Research Center will be ready for clinical use, Agence France-Presse reports. Ho, at a meeting in Beijing of the Society of Chinese Bioscientists in America, said one vaccine is already in early human tests in New York City. Human trials of the second vaccine are expected to begin by the end of the year. The vaccines use genes from the strain of HIV common in China and throughout Asia. They aim to produce a protective effect against HIV infection by priming the body's immune system to recognize and attack the invading virus.