A live attenuated Listeria monocytogenes vaccine vector expressing SIV Gag is safe and immunogenic in macaques and can be administered repeatedly

Vaccine. 2011 Jan 10;29(3):476-86. doi: 10.1016/j.vaccine.2010.10.072. Epub 2010 Nov 9.

Abstract

Listeria monocytogenes (Lm) is known to induce strong cellular immune responses. We constructed a live-attenuated Lm vector, Lmdd-BdopSIVgag, which encodes SIVmac239 gag. Intragastric (i.g.) administration of 3 × 10(12) bacteria to rhesus macaques was safe and induced anti-Gag cellular but no humoral immune responses. Boosting of Gag-specific cellular responses was observed after i.g. administration of Lmdd-BdopSIVgag to previously vaccinated RM despite preexisting anti-Lm immunity shown by lymphoproliferative responses. Surprisingly, anti-Lm cellular responses were also detected in non-vaccinated controls, which may reflect the fact that Lm is a ubiquitous bacterium. The novel, live-attenuated Lmdd-BdopSIVgag may be an attractive platform for oral vaccine delivery.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Drug Carriers*
  • Gene Products, gag / genetics
  • Gene Products, gag / immunology*
  • Genetic Vectors*
  • Immunity, Cellular
  • Immunization, Secondary / methods
  • Listeria monocytogenes / genetics*
  • Macaca mulatta
  • SAIDS Vaccines / administration & dosage
  • SAIDS Vaccines / genetics
  • SAIDS Vaccines / immunology*
  • Simian Immunodeficiency Virus / genetics
  • Simian Immunodeficiency Virus / immunology*
  • Vaccination / methods
  • Vaccines, Attenuated / administration & dosage
  • Vaccines, Attenuated / genetics
  • Vaccines, Attenuated / immunology

Substances

  • Drug Carriers
  • Gene Products, gag
  • SAIDS Vaccines
  • Vaccines, Attenuated