Vaccinia virus vectors with deleted serpin genes induce immune response.

2004 MAY 5 - (NewsRx.com & NewsRx.net) -- Attenuated vaccinia virus vectors with deleted serpin genes induce potent humoral and cell-mediated immune responses.

According to published research from the United States, "Vaccinia virus (VV) has been effectively utilized as a live vaccine against smallpox as well as a vector for vaccine development and immunotherapy. Increasingly there is a need for a new generation of highly attenuated and efficacious VV vaccines, especially in light of the AIDS pandemic and the threat of global bioterrorism. We therefore developed recombinant VV (rVV) vaccines that are significantly attenuated and yet elicit potent humoral and cell-mediated immune responses.

"B13R (SPI-2) and B22R (SPI-1) are two W immunomodulating genes with sequence homology to serine protease inhibitors (serpins) that possess anti-apoptotic and anti-inflammatory properties," said Fatema A. Legrand and colleagues at the University of California-Davis. "We constructed and characterized rVVs that have the B13R or B22R gene insertionally inactivated (vDeltaB13R and vDeltaB22R) and coexpress the vesicular stomatitis virus glycoprotein (v50DeltaB13R and v50DeltaB22R). Virulence studies with immunocompromised BALB/cBy nude mice indicated that B13R or B22R gene deletion decreases viral replication and significantly extends time of survival.

"Viral pathogenesis studies in immunocompetent CB6F[subscript]1 mice further demonstrated that B13R or B22R gene inactivation diminishes VV virulence, as measured by decreased levels of weight loss ...