The application provides polypeptides comprising or essentially consisting of at least one heavy chain variable domain of a heavy chain antibody (V.sub.HH) or a functional fragment thereof, wherein said V.sub.HH or a functional fragment thereof specifically binds to a target protein that is present on and/or specific for a solid tumor, e.g. HER2. The application further provides nucleic acids encoding such polypeptides; methods for preparing such polypeptides; host cells expressing or capable of expressing such polypeptides; compositions, and in particular to pharmaceutical compositions, that comprise such polypeptides, nucleic acids and/or host cells. The application further provides such polypeptides, nucleic acids, host cells and/or compositions, for use in methods for detection, imaging, prognosis and diagnosis of cancer as well as for predicting patient response(s) to therapeutics.

The application provides polypeptides comprising or essentially consisting of at least one heavy chain variable domain of a heavy chain antibody (V.sub.HH) or functional fragments thereof, wherein said V.sub.HH or functional fragment thereof specifically binds to a target protein that is present on and/or specific for a solid tumor or cancer cell, e.g., HER2. The application further provides nucleic acids encoding such polypeptides; methods for preparing such polypeptides; host cells expressing or capable of expressing such polypeptides; compositions, and in particular to pharmaceutical compositions that comprise such polypeptides, nucleic acids and/or host cells. The application further provides such polypeptides, nucleic acids, host cells and/or compositions, for use in methods for the prevention and/or treatment of cancer.

The invention relates generally to antibodies and antigen-binding fragments thereof that bind activatable antibodies and/or conjugated activatable antibodies and methods of making and using these antibodies that bind activatable antibodies and/or conjugated activatable antibodies.

This invention provides a composition comprising an effective amount of monoclonal antibody 8H9 or a derivative thereof and a suitable carrier. This invention provides a pharmaceutical composition comprising an effective amount of monoclonal antibody 8H9 or a derivative thereof and a pharmaceutically acceptable carrier. This invention also provides an antibody other than the monoclonal antibody 8H9 comprising the complementary determining regions of monoclonal antibody 8H9 or a derivative thereof, capable of binding to the same antigen as the monoclonal antibody 8H9. This invention provides a substance capable of competitively inhibiting the binding of monoclonal antibody 8H9. This invention also provides an isolated scFv of monoclonal antibody 8H9 or a derivative thereof. This invention also provides the 8H9 antigen. This invention also provides a method of inhibiting the growth of tumor cells comprising contacting said tumor cells with an appropriate amount of monoclonal antibody 8H9 or a derivative thereof.

A method for producing a conjugate of a radioactive metal nuclide and an antibody is provided, and the method includes a step of reacting a radioactive metal nuclide with an antibody conjugated with a ligand compound in a reaction solution containing water to coordinate the radioactive metal nuclide to the ligand compound, and the reaction solution does not contain a pH buffer and has a pH of 2 or more and 10 or less. The radioactive metal nuclide is preferably at least one selected from .sup.68Ga, .sup.89Zr, .sup.90Y, .sup.111In, .sup.177Lu, and .sup.225 Ac. It is also preferable that the radioactive metal nuclide be .sup.89Zr and the reaction solution have a pH of 2 or more and 4 or less.