T cell receptor, CD4 and MHC proteins. Illustration of a cell membrane with a T cell receptor (dark blue, centre) in complex with an MHC (major histocompatibility complex) class II-peptide complex (purple). The T cell receptor activates the immune...

T cell binding antigen, illustration

"Cancer cell, illustration"

"Cancer cell, illustration"

T-cells and dendritic cell interacting. Illustration of a dendritic cell (light blue, centre) interacting with T-cells (bright blue, round). Both cells are components of the body's immune system. Dendritic cells are antigen-presenting cells (APCs),...

Lymphocytes, illustration

Programmed cell death in immune system, illustration. The protein PD-1 (programmed cell death protein 1, red) is seen extending from the surface membrane of a T-cell (across bottom), interacting with the ligand protein PD-L1 (orange) from an antigen...

Lymphocytes, illustration

Lymphocytes, illustration

T- and B-lymphocyte, illustration

T- and B-lymphocyte, illustration

T-cell receptors, illustration. Array of immunologically active proteins and a calcium ion channel (dark purple, upper centre) on the membrane of a T-cell, a key part of the immune system. These proteins are involved in both the activation and...

T-cell receptor-MHC-antigen complexes