CD2 and osteosarcoma: Second, cytokine therapy can enhance the conjugate-forming capacity of NK cells to osteosarcoma targets by augmenting the expression of CD18 and CD2 (68) (both of which are adhesion molecules on NK cells), and intercellular adhesion molecule (ICAM)-1 (67) and fibronectin (69) (both of which are adhesion molecules on osteosarcoma cells).