Muscle-infiltrating T cells are CD4<sup>+</sup> and express CD25 and CD69.

<p>(A–B) Flow cytometric analysis of CD4 and CD8 expression on CD3<sup>+</sup> T cells harvested from injured skeletal muscle. A representative plot from day 3 is shown at left and data are summarized at right as % CD4<sup>+</sup> or % CD8<sup>+</sup> at each time point analyzed (n ≥ 4 mice per time point, mean ± SEM). (C–D) The majority of CD3<sup>+</sup>CD4<sup>+</sup> cells express CD25 (range: 86–97%), CD69 (34–66%), but not CD44 (0.1–4%) (n ≥ 4 mice per time point, mean ± SEM).</p>