Also, despite the description of CD47 expression as an advantageous feature for neoplastic cells, CD47 ligation by monoclonal antibodies can induce apoptosis in many tumor cell lines, such as chronic lymphocytic leukemia cells (24), and binding of CD47 by TSP-1 has also been described to induce cell apoptosis (14). The gene discussed is CD47; the disease is B-cell chronic lymphocytic leukemia.