Vaccination with Attenuated Simian Immunodeficiency Virus by DNA Inoculation

Delivering attenuated lentivirus vaccines as proviral DNA would be simple and inexpensive. Inoculation of macaques with wild-type simian immunodeficiency virus strain mac239 (SIV(mac239)) DNA or SIV(mac239) DNA containing a single deletion in the 3′ nef-long terminal repeat overlap region (nef/LTR) led to sustained SIV infections and AIDS. Injection of SIV(mac239) DNA containing identical deletions in both the 5′ LTR and 3′ nef/LTR resulted in attenuated SIV infections and substantial protection against subsequent mucosal SIV(mac251) challenge.