Figure 3: Trm cells improve circulating memory-mediated immunity to melanoma.

(a) Scheme for parabiosis strategy. Mice were s.s. and i.d. vaccinated with rVACV-OVA. After 30 days, vaccinated mice were each surgically joined with a naive mouse. Thirty days after surgery, parabiotic pairs were separated and allowed to recover for 30 days before i.d. inoculation of B16-OVA (10⁶ cells) in the flank. (b) Frequency (top) and absolute numbers (bottom) of CD8⁺CD44⁺KbOVA⁺ circulating memory T cells in the blood after parabiosis and before tumour inoculation. (c) Tumour incidence represented as the frequency of detectable tumours incidence over time. The dashed line indicates 50% of tumour incidence. (d) Tumour growth curve plotted as tumour size (mm³) over time. Pool of two independent experiments represented as individual data and mean±s.e.m. (b), as percentages (c) and as tumour size mean±s.e.m. (d) (n=5–6 per control group and 8–9 per vaccinated group). NS, not significant, ***P<0.001; **P<0.01 by two-tailed unpaired Student’s t-test (b), Cox mixed model (c) and two-way ANOVA (d) with Bonferroni post-hoc test.