Figure 1.

Cyclophilin-mediated Ca²⁺ signaling in T lymphocytes. Ca²⁺ mobilization in Fluo-3-loaded T cells was measured in the presence of CyPB (50 nM) (A and B), CyPA (250 nM) (C and D), CyPB_KKK− (50 nM) (E), or CyPB/CsA (50 nM) (F). The arrows indicate the addition of the agonist. Cells were either directly stimulated with the agonist for analysis (A, C, E, F) or prestimulated with CyPA (B) or CyPB (D) before a second stimulation. Changes in fluorescence, reflecting changes in cytosolic Ca²⁺ concentration, were monitored by flow cytofluorimetry. Tracings are from a single representative experiment.