BCG vaccine with recombinant vaccinia virus Ankara boost protects against TB.

2003 SEP 17 - (NewsRx.com & NewsRx.net) -- Enhanced immunogenicity and protective efficacy was achieved against Mycobacterium tuberculosis using mucosal administration of bacille Calmette-Guerin vaccine and boosting with a recombinant modified vaccinia virus Ankara.

"Heterologous prime-boost immunization strategies can evoke powerful T cell immune responses and may be of value in developing an improved tuberculosis vaccine. We show that recombinant modified vaccinia virus Ankara, expressing Mycobacterium tuberculosis antigen 85A (M.85A), strongly boosts bacille Calmette-Guerin (BCG)-induced antigen 85A specific CD4+ and CD8+ T cell responses in mice," researchers in England report.

"A comparison of intranasal (i.n.) and parenteral immunization of BCG showed that while both routes elicited comparable T cell responses in the spleen, only i.n. delivery elicited specific T cell responses in the lung lymph nodes, and these responses were further boosted by i.n. delivery of M.85A," stated Nilu P. Goonetilleke and associates at Oxford University. "Following aerosol challenge with M. tuberculosis, i.n. boosting of BCG with either BCG or M.85A afforded unprecedented levels of protection in both the lungs (2.5 log) and spleens (1.5 log) compared with naive controls. Protection ...