Measurement of Calcium Mobilization Responses in Killer Cell/Target Conjugates by FACS Analysis

The interaction between killer cells and target cells can be dissected into three steps. First, the two cells form random conjugates mediated by nonspecific interactions between adhesion molecules (1 ). Second, specific recognition results in the activation of signal transduction pathways coupled to activating receptors and accessory molecules (2 ). This leads to the third step consisting of perforin and/or fas-ligand mediated delivery of the lethal hit (3 ). Lethal hit delivery requires a short time; as a consequence killer cells can recycle and kill multiple targets (4 ).