Figure 1

Localisation of endogenous FasL in primary human T cells. In human T cell blasts, FasL is stored within the cell in distinct intracellular granules (A). Upon target cell encounter, these granules are transported to the site of intercellular contact, thus placing FasL on the cell surface in the immunological synapse (B). T cell blasts were left untreated (A) or incubated with a superantigen-pulsed EBV-transformed B-cell lymphoblastic cell line (*) for 30 minutes (B), fixed, permeabilised and stained for endogenous FasL with anti-FasL mAb NOK-1 and AlexaFluor 488-conjugated donkey anti-mouse IgG.