Encouraging New Approach to an HIV Vaccine

HIV and its monkey counterpart SIV typically infect mucosal cells, where they proliferate before disseminating to lymphoid tissues and other organs. Until now, HIV or SIV vaccines generally have been of the type that elicit neutralizing antibodies and killer CD8⁺ cells against the viruses. However, these immunological responses aren't produced rapidly enough to stop the local mucosal infection from disseminating.

Investigators introduced genes for several SIV proteins into a monkey cytomegalovirus (CMV). CMV infections are lifelong, and the researchers had found previously that persistent production of SIV proteins elicited a rapid immunological attack on SIV in mucosal tissue — before SIV could disseminate. Twenty-four monkeys were given th…