Genes up-regulated in comparison of splenic primary CD8 effector T cells at day 8 post-acute infection versus splenic primary CD8 effector T cells at day 8 post-chronic infection.
Full description or abstract
Understanding the response of memory CD8 T cells to persistent antigen re-stimulation and the role of CD4 T cell help is critical to the design of successful vaccines for chronic diseases. However, studies comparing the protective abilities and qualities of memory and naïve cells have been mostly performed in acute infections, and little is known about their roles during chronic infections. Herein, we show that memory cells dominate over naïve cells and are protective when present in large enough numbers to quickly reduce infection. In contrast, when infection is not rapidly reduced, memory cells are quickly lost, unlike naïve cells. This loss of memory cells is due to (i) an early block in cell proliferation, (ii) selective regulation by the inhibitory receptor 2B4, and (iii) increased reliance on CD4 T cell help. These findings have important implications towards the design of T cell vaccines against chronic infections and tumors.
