India, July 8 -- A study published in the journal Nature late last month has done something no HIV vaccine has managed before: triggered protective levels of HIV-fighting antibodies in monkeys with entirely ordinary and unmodified immune systems.

It is a narrow result - only one animal in the trial reached that protective threshold, and fewer than half showed any antibody response at all. But researchers behind the work say its significance lies less in its scale than in how it was achieved, after more than a decade of research and a long run of failed HIV vaccines before it.

The vaccine was developed by a consortium that included Scripps Research, the La Jolla Institute for Immunology (LJI) and the International AIDS Vaccine Initiative...