On the cover: The NKG2D activating receptor is expressed on a fraction of mature thymocytes present in the thymic medulla only. Double staining with FITC-labeled MICA tetramers (green) and rhodamine-labeled anti-keratin antibody (red) on human normal thymus localizes NKG2D-positive cells to the medullar areas, in the vicinity of blood vessels. Hüe et al. Potential role of NKG2D/MHC Class I-Related Chain A Interaction in Intrathymic Maturation of Single-Positive CD8 T cells. 1909.)