CD22 and neoplasm: In the last few years, several anti-CD20 and anti-CD22 ITs composed of mAbs linked to RIPs [15,16,29], bacterial toxins [30], ribonucleases [31], drugs [32,33], or radioisotopes [1,2] have demonstrated potent anti-tumor effects in vitro and in vivo in animal models and, in some cases, also in clinical trials.