CD45 pre-exclusion from the tips of T cell microvilli prior to antigen recognition

Abstract

CD45 limits T cell activation, so its exclusion from the T cell immunological synapse is thought to occur as a means to enable TCR signalling. Here the authors use a variety of cellular imaging methods to show that CD45 is indeed excluded from the tips of the T cell microvilli and that this occurs prior to contact with antigen, indicating this exclusion is one of the initiating factors for antigen presentation and T cell activation.