Exhausted T cells perk up

摘要

During persistent infections, the immune cells responsible for killing infected cells and maintaining inflammation gradually stop functioning, allowing the pathogen to thrive. But can this process be reversed? There are many checks and balances in place to control the immune response to a pathogenic onslaught: too little of a reaction and the invader can kill the host or take up residence; too much and the immune system can itself start to damage tissues. On page 682 of this issue, Barber et al. demonstrate that a recep-tor-ligand pair involved in controlling the immune response can be blocked by antibodies to revive dysfunctional T cells and clear a chronic viral infection.