CD22 and neoplasm: With apoptosis-inducing protein (apoptin) recruited for tumor apoptosis, the fusion protein demonstrated cytotoxicity in Raji cells while not binding to CD22-negative Jurkat cells as demonstrated in 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and annexin V/propidium iodide flow cytometry analysis.62