CD1D and Hodgkins lymphoma: We thank Alessandro Moretta for providing monoclonal antibodies anti-NK cells receptors, produced in his Laboratory of Dipartimento di Medicina Sperimentale, Università di Genova, Italy, Marco Cassatella (University of Verona) for providing L428 and L540 cell lines Hodgkin's lymphoma derived, NIH Tetramer Core Facility at Emory, Atlanta for providing PBS57-loaded and PBS57-unloaded CD1d tetramers.