Passport delays: applicants' long and frustrating wait. 1  Backlog caused by spike in applications has thrown many people's plans into chaos with some having to resort to desperate measures. 2  Backlog caused by spike in applications has thrown many people's plans into chaos with some having to resort to desperate measures.
Suppressor T cell. Definition. noun. A type of T cell that expresses CD8 transmembrane glycoprotein, and functions by inhibiting, suppressing, or helping to stop an immune response by releasing signals to other immune cells. Supplement. Examples of suppressor T cells are suppressor macrophages.
One way this is done through inhibitory receptors, such as PD-1. After activation, T cells increase the expression of PD-1 on their surface, allowing them to receive a shut down signal. Tumor cells have taken advantage of this system by expressing binding partners of PD-1, prematurely shutting down the T cells.