Genes from replicative form of Trypanosoma cruzi protect mice.

A DNA vaccine containing genes expressed by the replicative form of Trypanosoma cruzi, the parasite responsible for Chagas Disease, protected mice from a challenge with a potentially lethal dose of organisms, according to a report in the 2003 issue of the journal 'Infection and Immunity.' "Immunization of mice with plasmids containing Trypanosoma cruzi genes induced specific antibodies, CD4+ Th1 and CD8+ Tc1 cells, and protective immunity against infection," reported researcher Silvia B. Boscardin and colleagues at the Universidade Federal de Sao Paulo in Brazil. The investigators chose a gene that controlled expression of the amastigote surface protein 2 (ASP-2), which is known to be antigenic in mice and humans and elicits both humoral and cellular immune responses. Amastigote cDNA is an interesting source of antigens that can be used for immunological studies, as well as for vaccine development.