Document 0776
 DOCN  M9590776
 TI    Prior infection with a nonpathogenic chimeric simian-human
       immunodeficiency virus does not efficiently protect macaques against
       challenge with simian immunodeficiency virus.
 DT    9509
 AU    Letvin NL; Li J; Halloran M; Cranage MP; Rud EW; Sodroski J; Harvard
       Medical School, Beth Israel Hospital, Boston,; Massachusetts 02215, USA.
 SO    J Virol. 1995 Jul;69(7):4569-71. Unique Identifier : AIDSLINE
       MED/95287522
 AB    Prior infection with a nef-deleted simian immunodeficiency virus (SIV)
       protects macaques not only against a homologous pathogenic SIV challenge
       but also against challenge with a chimeric SIV expressing a human
       immunodeficiency virus type 1 env gene (SHIV). Since this SHIV is itself
       nonpathogenic, we sought to explore the use of a nonpathogenic SHIV as a
       live, attenuated AIDS virus vaccine. Four cynomolgus monkeys infected
       for greater than 600 days with a chimeric virus composed of SIVmac 239
       expressing the human immunodeficiency virus type 1 HXBc2 env, tat, and
       rev genes were challenged intravenously with 100 animal infectious doses
       of the J5 clone of SIVmac 32H, an isolate derived by in vivo passage of
       SIVmac 251. Three of the four monkeys became infected with SIVmac. This
       observation underlines the difficulty, even with a live virus vaccine,
       in protecting against an AIDS virus infection.
 DE    Animal  AIDS Vaccines/*IMMUNOLOGY  Chimera  Macaca  Simian Acquired
       Immunodeficiency Syndrome/*PREVENTION & CONTROL  Support, Non-U.S. Gov't
       Support, U.S. Gov't, P.H.S.  SAIDS Vaccines/*IMMUNOLOGY  Vaccines,
       Attenuated/IMMUNOLOGY  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).