CD22 is a protein expressed by normal B cells and B-lymphoid malignancies. Its limited tissue expression pattern makes it a safe antigen for targeted therapies, such as T-cell Receptor (TCR)-T cell therapy. CD22-targeting therapies already on the market, mainly antibody-immunotoxin conjugates and chimeric antigen receptors (CAR)-T cells, have limitations such as resistance to treatment and/or side effects. Resistance mechanisms to the current CD22 therapies involve loss or modulation of target antigen on the cell surface.