The highly organized region of contact between an effector CD4 T cell and its target antigen-presenting cell. It involves clustering of T-cell receptors within a local area of the T-cell plasma membrane and of complexes of the antigen-MHC class II protein in the apposed part of the target cell. With the additional involvement of coreceptors and adhesion molecules, this creates a supramolecular adhesion complex (SMAC). The T cell then becomes polarized, which focuses the secretion of soluble cytokines at the point of contact between the cells.
Subjects: Medicine and Health — Biological Sciences.