Salmonella secretion antigen delivery primes SIV-specific T-cell response.

2003 APR 2 - (NewsRx.com & NewsRx.net) -- Mucosal priming of simian immunodeficiency virus-specific cytotoxic T-lymphocyte responses were found in rhesus macaques that received a Salmonella type III secretion antigen delivery system.

According to a study from the United States, "Nearly all human immunodeficiency virus (HIV) infections are acquired mucosally, and the gut-associated lymphoid tissues are important sites for early virus replication. Thus, vaccine strategies designed to prime virus-specific cytotoxic T lymphocyte (CTL) responses that home to mucosal compartments may be particularly effective at preventing or containing HIV infection."

"The Salmonella type III secretion system has been shown to be an effective approach for stimulating mucosal CTL responses in mice," said David T. Evans and colleagues at the New England Regional Primate Research Center, Yale School of Medicine, Therion Biologics Corporation, and the National Cancer Institute at Frederick. "We therefore tested delta-phoP-phoQ attenuated strains of Salmonella enterica serovar Typhimurium and S. enterica serovar Typhi expressing fragments of the simian immunodeficiency virus (SIV) Gag protein fused to the type III-secreted SopE protein for the ability to prime virus-specific CTL responses in rhesus macaques. Mamu-A*01[superscript]+ macaques were inoculated with three oral doses of recombinant Salmonella, followed by a peripheral boost with modified vaccinia virus Ankara expressing SIV Gag (MVA Gag)."

"Transient low-level CTL responses to the Mamu-A*01 Gag(181-189) epitope were detected following each dose of Salmonella," reported the investigators. "After boosting with MVA Gag, strong Gag-specific CTL responses were consistently detected, and tetramer ...