Shaping Successful and Unsuccessful CD8 T Cell Responses Following Infection
Figure 1
Pathogen-specific T cell responses to acute and chronic infections vary in magnitude and functional attributes. (a) Acute infections elicit a large CD8 T cell response, and after resolution of the infection the memory pool is typically composed of polyfunctional T cells capable of coproducing IFN, TNF, and IL-2 (green circles) or IFN and TNF (blue circles). (b) Protracted infections are associated with weaker responses and reductions in the functional quality of the responding T cells, such as the emergence of CD8 T cells which only produce IFN (red circles) as well as the development of exhausted cells that are functionally incapacitated (black circles). The overall quality of the response may improve as the infection is brought under control. (c) High-grade viral persistence during chronic infection results in severe functional exhaustion and the possible deletion of antigen-specific CD8 T cells.
