FIG 4.

Infection with the cyst life cycle stage drives the recruitment of T and B cells into the lungs of adult mice. Adult BALB/cJ mice were infected i.t. with 5 × 10⁶ trophic forms or mixed P. murina organisms. Flow cytometry was used to phenotype activated CD4⁺ T cells (A), activated CD8⁺ T cells (B), and CD19⁺ B cells (C) in the BALF, lung digest, and TBLN. Activation of T cells was evaluated by CD44 and CD62L expression. Data are means ± standard deviations for 5 mice per group and are representative of 2 separate experiments. For comparison of mean total cell numbers between the groups at individual time points, t tests were used. *, P ≤ 0.05; **, P ≤ 0.01; ***, P ≤ 0.001.