Real-time imaging of T-cell development.

The cellular and molecular dynamics underlying intrathymic T-cell development are still poorly understood. Dynamic imaging techniques offer new opportunities for dissecting the complex journey of developing T cells in the thymus. In particular, two-photon laser scanning microscopy has recently demonstrated great promise in tracking lymphocyte behavior in tissue environments. Resolving thymocyte behavior at the single-cell level should help to clarify the mode of trafficking in the thymus and identify the spatio-temporal aspects of thymic selection events.