Abstract: The present invention relates generally to compositions useful in therapies involving the selective destruction of tumor cells in vivo. In particular, this invention relates to a conjugate which comprises a target recognition segment and an active cytotoxic segment. The target recognition segment comprises a receptor specific to NK cells, wherein the receptor binds to a cellular ligand expressed on the surface of a tumor cell, and the active segment comprises an agent capable of exerting a cytotoxic effect on the tumor cell. The target recognition segment derived form the natural killer receptor NKp30 has been found to be particularly effective in vivo.

Abstract: The present invention relates in general to specific NCR-derived peptides capable of binding to membrane-associated biomolecules of the tumor cells, said biomolecules comprising at least one sulfated polysaccharide. Preferred peptides are about 7 to about 120 amino acids in length and are derived from NKp-44, NKp30 or NKp46.

Abstract: The present invention relates generally to peptides derived from the natural cytotoxicity receptors on natural killer (NK) cells and to antibodies against peptide epitopes on these receptors. In particular, the present invention identifies an essential epitope in the proximal domain of NKp46 and NKp44 receptors present on NK cells, as a crucial element for the binding to viral-infected cells. The present invention provides peptides that are derived from the amino acid sequence of NKp46 receptor, capable of specific targeting of viral-infected cells and tumor cells and monoclonal antibodies which recognize a specific domain of NKp46. The present invention further provides hyperglycosylated peptides that are derived from the NKp44 receptor, capable of specific targeting of viral-infected cells.

Abstract: The present invention relates generally to compositions useful in therapies involving the selective destruction of tumor cells in vivo. In particular, this invention relates to a conjugate which comprises a target recognition segment and an active cytotoxic segment. The target recognition segment comprises a receptor specific to NK cells, wherein the receptor binds to a cellular ligand expressed on the surface of a tumor cell, and the active segment comprises an agent capable of exerting a cytotoxic effect on the tumor cell. The target recognition segment derived form the natural killer receptor NKp3O has been found to be particularly effective in vivo.

Abstract: The invention relates to a targeting complex, capable of targeting an active substance to a target cell, said complex comprising: a target recognition segment comprising one of NKp46, NKp30, NKp44 or a functional fragment thereof; and an active segment comprising an active substance such as cytotoxic moiety; an imaging moiety; or an Ig fragment. The targeting complex of the invention serves as a therapeutic agents for the treatment of pathologies associated with viral infections or cancer and for the imaging and monitoring of cancer.