To gain insight into the molecular properties of the NKp46/Ncr1 unknown tumor ligand and to test whether the O- and N-glycosylations of Ncr1 are involved in its tumor recognition, we prepared an additional Ncr1 fusion protein, in which all N-linked glycosylated residues are mutated (Ncr1 N139 216 238A Ig). Here, NCR1 is linked to neoplasm.