Potency-tuned cd70 ligands, targeted chimeric antigen receptors (cars) and methods for cancer

Cd70 binding proteins or ligands, particularly cd27 polypeptides, and particularly variant cd27 extracellular binding domain polypeptides, are provided wherein the cd27 amino acid sequence is altered. the cd27 polypeptides and/or domains thereof, particularly the extracellular binding domains thereof are useful in the diagnosis and treatment of various conditions, including in cancer and immunotherapuetics. the cd27 polypeptides and/or domains thereof, particularly the extracellular binding domains thereof may also be used in lymphoid cell-mediated, including t cell-mediated, therapy, in chimeric antigen receptor (car) therapy, and/or in therapy in combination with chemotherapeutics, radiation therapy, immune modulators, cancer vaccines, cancer antigens, or anti-cancer agents. particular variant cd27 polypeptides, extracellular domains, and novel car constructs are provided.