Figure 5From: Programmed cell death-1 (PD-1) at the heart of heterologous prime-boost vaccines and regulation of CD8+ T cell immunitySchematic representation of the kinetics of various subsets of T cells within secondary lymphoid organs. This is a complementary perspective to that in Figure 4B, providing a rationale to why a specific sequence of priming and boosting is important to generating an elevated immune response.Back to article page