Phentotypic analysis of ELC-responsive thymocytes. FACS analysis was performed on thymocytes after chemotaxis towards an optimal concentration of ELC (500 nmol/L). The left-hand panel shows staining of freshly isolated thymocytes with CD4 and CD8, whereas the right-hand panel shows staining of those thymocytes that had migrated in response to ELC. Data shown are representative of 3 separate experiments.