title: Partial protection of SHIV-infected Chinese rhesus macaques against super-infection with heterologous SHIV isolate.
abstract: BACKGROUND
  Many studies have revealed a protective effect of infection with simian immunodeficiency virus (SIV) or simian-human immunodeficiency virus (SHIV) against subsequent infection by a related immunodeficiency virus. However, whether a protective response can be induced by an infection with an immunodeficiency virus is still currently debated in the HIV-1 vaccine field. The aim of this study was to evaluate the protection against SHIV challenge in Chinese macaques that had been inoculated with SHIVs containing different HIV-1 envelops.
  
  
  METHODS
  Eleven adult Chinese rhesus monkeys were inoculated with SHIV-KB9, SHIV-1157ipd3N4 or SHIV-CN97001. After 30 weeks, the animals were exposed to SHIV-KB9 or SHIV-CN97001, which carried a heterologous envelope protein relative to the first challenge strain. Infection was monitored by measuring viral load and antibody response, as well as viral genome sequence analyses.
  
  
  RESULTS
  After first challenge, all the monkeys demonstrated high viral loads and specific antibody responses. Protection from super-infection was statistically significant in all the animals inoculated with SHIV-KB9 or SHIV-1157ipd3N4. However, animals inoculated with SHIV-CN97001 and challenged with SHIV-KB9 showed new infections. The susceptibility to super-infection was not correlated with neutralizing antibodies present at the time of exposure to the second virus.
  
  
  CONCLUSIONS
  These findings indicate that different SHIV infection may confer different levels of protection against a second SHIV infection in Chinese monkeys. Understanding this protective response in SHIV infected macaques may shed a new light on HIV-1 vaccine development.
authors.affiliation: College of Life Sciences, Nankai University, Tianjin, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Li
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liu
authors.forename: Zhenwu
authors.initials: Z
authors.lastname: Luo
authors.forename: Yanmeng
authors.initials: Y
authors.lastname: Feng
authors.forename: Zhe
authors.initials: Z
authors.lastname: Li
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wei
authors.forename: Yiming
authors.initials: Y
authors.lastname: Shao
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis; D004279:DNA, Viral / Q000032:analysis; D015686:Gene Products, env / Q000235:genetics / Q000276:immunology; D015497:HIV-1 / Q000235:genetics / Q000276:immunology*; D008253:Macaca mulatta; D008992:Monkey Diseases / Q000276:immunology*; D016097:Simian Acquired Immunodeficiency Syndrome / Q000276:immunology* / Q000821:virology; D015302:Simian Immunodeficiency Virus / Q000276:immunology* / Q000302:isolation & purification; D015163:Superinfection / Q000276:immunology* / Q000821:virology; D013601:T-Lymphocytes / Q000276:immunology; D014611:Vaccination / Q000379:methods; D019562:Viral Load; D014765:Viral Vaccines / Q000235:genetics / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; D004279:DNA, Viral; D015686:Gene Products, env; D014765:Viral Vaccines