FIG 5.

Memory CD8⁺ T cell responses in the absence of TSKB20- and TSKB18-specific CD8⁺ T cells. WT littermates or TSKB20/18 Tg mice (both CD45.1/CD45.2) were infected with 1 × 10³ T. cruzi organisms, treated orally with benznidazole daily for 40 consecutive days, beginning at 15 days postinfection, and sacrificed >200 days after cessation of treatment. CD8⁺ T cells (2 × 10⁶) from spleens and lymph nodes of treated WT or TSKB20/18 Tg mice were transferred into uninfected WT or TSKB20/18 Tg (both CD45.2), respectively. Recipients were challenged the following day with 1 × 10⁴ T. cruzi organisms. (A) Surface phenotype of CD45.1⁺ CD8⁺ T cells before adoptive transfer (left) and in the peripheral blood of recipients 13 days after challenge (right). Numbers indicate percentages of events in the gate. (B) Total number of donor CD45.1⁺ CD8⁺ T cells recovered from spleens of challenged mice (filled symbols) at 21 days postinfection.