Prime-Boost Regimens Enhance DNA Vaccine Efficacy.(Brief Article)

2001 FEB 14 - (NewsRx.com & NewsRx.net) --

- by Michelle Marble, staff medical writer -- Knowing when, how much, and how often helped researchers in England improve the immunogenicity and efficacy of a DNA vaccine against Mycobacterium tuberculosis.

"DNA vaccines whose DNA encodes a variety of antigens from M. tuberculosis have been evaluated for immunogenicity and protective efficacy," said Helen McShane and colleagues, University of Oxford. "CD8(+) T-cell responses and protection achieved in other infectious disease models have been optimized by using a DNA immunization to prime the immune system and a recombinant virus encoding the same antigen(s) to boost the response."

McShane et al. published their report in the journal Infection and Immunity ("Enhanced immunogenicity of CD4(+) T-cell responses and protective efficacy of a DNA-modified vaccinia virus Ankara prime-boost vaccination regimen for murine tuberculosis," Infect and Immun, February 2001;69(2):681-686).

The researchers developed a DNA vaccine (D) and a recombinant modified vaccinia virus Ankara (M). The DNA in these vaccines encoded early secreted antigenic target 6 and mycobacterial protein tuberculosis 63 synthesized. Immunization with either generated specific gamma interferon (IFN)-secreting CD4(+) T cells.

"Enhanced CD4(+) IFN T-cell responses were produced by both D-M and M-D immunization ...