Leslie found that the VAV exchange factor for rac was required for formation of the CAP or SMAC or immune synapse signaling complex on lymphocytes and also for T cell receptor signals to activate NFAT-dependent transcription and lead to T cell activation.. In addition, she used synthetic ligands to demonstrate that the SOS exchange factor could be activated by membrane proximity. She now works at Sugen in Redwood City and can be reached at: lholsing@sugen.com