Figure 2. PD-1 deficiency increases CD8⁺ T cell activation in hypercholesterolemic mice.

a) Circulating numbers of CD8⁺ T cells in Ldlr^{− /−} or Ldlr^{− /−} Pd1^{− /−} mice after 9 weeks of high fat diet feeding. Quantification of frequencies of CD44^hiCD62L⁻ effector/memory cells among CD45⁺CD3⁺TCRβ⁺ CD8⁺ T cells in blood (b), spleen (c) and peripheral LN (d) after 9 weeks of high fat diet feeding (n = 5/group). *p<0.05.