CD28 and infection: Upon in vitro restimulation in presence anti-CD3 and anti-CD28 antibodies, there were significant changes in CD8 T cells isolated from both infection conditions, especially regarding inhibitory receptor genes, such as Pdcd1 (encoding PD-1) and Cd160, and cytokine production-related transcripts like Ifng, Tnf, Il10, and Xcl1, demonstrating that exhausted CD8 T cells are not inherently unable to transmit TCR signals into a transcriptional output.