all of these cells may use NTs to communicate and coordinate immune responses. Through NT coordination, B cell activation could be transmitted to distant T cells [33], activating signals could be generally transmitted to a whole network of NT-connected cells [14], or, in the case of NK cells, NK-dendritic cell crosstalk and the transmission of cytokines, both to and from the NK cell, could be mediated over long distances via NTs. Interestingly, CD2’s cognate ligand, CD58, is widely expressed on hematopoietic cells, making it an ideal candidate for promoting NT formation and subsequent crosstalk between a variety of immune cells. While the role for CD2 in NT formation in other immune cells remains unexplored, we demonstrate for the first time that the CD2 receptor-ligand interaction plays a crucial role in NK to target cell NT formation. 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