IL-15 ablation in non-hematopoietic cells reduces inflationary T cell maintenance.

(A) Lung lymphocytes were isolated from naïve C57BL/6 mice and sorted according to CD45 staining. Relative Il15 mRNA levels normalized to β-actin internal controls was calculated using the ΔΔCT method, shown as mean + SEM of n = 6 mice pooled from two independent experiments. (B) Experimental setup: Naïve IL-15-/- and Thy1.1 mice were lethally irradiated and reconstituted with indicated bone marrow cells. Inflationary Maxi TEM cells were sorted from lungs of latently infected donor mice and transferred into the chimeras. The total numbers of Maxi cells were assessed four weeks post transfer. Total numbers of Maxi CD8 T cells in lungs (C), and spleen (D) at four weeks post transfer are shown as mean + SEM of n = 12–15 mice pooled from three independent experiments. (A; C-D); *p<0.05; **p<0.01; ***p<0.001; ****p<0.0001. Statistical analyses were performed using the non-parametric Mann-Whitney U test.