Figure 6. Long-term protective immunization with TCC dhfr-ts^+/− metacyclic trypomastigotes against virulent challenge with T. cruzi CL-tdTomato.

A) CD8⁺ T cells positive for TSKB20 at day 300 post infection in B6 mice inoculated with 5×10⁵ metacyclic trypomastigotes of mutant and wild type TCC parasites. B) Parasite load after challenge, at day 370 post infection, with 2.5×10⁵ bloodstream forms of the virulent CL-tdTomato strain. Fluorescence levels were measured during 13 days. Values are given as means; error bars indicate standard errors of the means.