Figure 4.

Many newly recruited T_RM are derived from peripheral memory T cells. (A) Experimental design. Mice were administered P14 1 day prior to infection with X31-GP33. 30 DPPI, all of the mice were exposed to 10 Gy of thorax-targeted radiation. 14 DPR, half of the mice were administered an anti-CD90.1 to deplete circulating Thy1.1 P14 or isotype control antibodies. Mice were then infected IN with a sublethal PR8-GP33 boost. 30 days later, mice were euthanized, and lungs and spleens were analyzed by flow cytometry. (B–H) Flow cytometric analysis was utilized to count the total number of (B) IV-negative CD8⁺ T cells in the lungs, (C) IV-negative P14 cells in the lungs, and (D) CD69⁺CD103⁺ P14 lung T_RM. In the same mice, flow cytometric analysis was utilized on whole spleens to enumerate the total number of (E) CD8⁺ T cells, (F) P14 cells, (G) T_CM P14 cells, and (H) T_EM P14 cells. Mann–Whitney test was utilized to determine statistically significant differences between groups. The data are pooled from two independent experiments (n = 6 mice per group). Statistical significance has been indicated within the figures with asterisks (*P = 0.03, **P = 0.002).