The present invention provides methods and compositions for treatment, screening, diagnosis and prognosis of acute myeloid leukemia (AML), B-cell chronic lymphocytic leukemia, breast cancer, colorectal cancer, kidney cancer, head and neck cancer, lung cancer, ovarian cancer or pancreatic cancer, for monitoring the effectiveness of acute myeloid leukemia (AML), B-cell chronic lymphocytic leukemia, breast cancer, colorectal cancer, kidney cancer, head and neck cancer, lung cancer, ovarian cancer or pancreatic cancer treatment, and for drug development. The present invention also provides methods and compositions for depletion of immune cells to treat inflammatory diseases.