Anti-CD20/CD3 BsNb can specifically bind to CD20 molecules on the surface of human lymphoma Raji cells and CD3 molecules on the surface of T cells in flow cytometry analysis and effectively mediate PBMCs target Raji cells with a killing efficiency of up to 30.4% as measured by the lactate dehydrogenase (LDH) method. This evidence concerns the gene MS4A1 and lymphoma.