TIGIT Marks Exhausted T Cells, Correlates with Disease Progression, and Serves as a Target for Immune Restoration in HIV and SIV Infection. - Chew GM; Fujita T; Webb GM; Burwitz BJ; Wu HL; Reed JS; Hammond KB; Clayton KL; Ishii N; Abdel-Mohsen M; Liegler T; Mitchell BI; et al. (PLoS pathogens, 2016)