Patent ID: 8809502

Claim:
An isolated anti-CD22 antibody with a variable light (V L ) chain having the sequence of the V L chain of antibody RFB4 and a variable heavy (V H ) chain having the sequence of the V H chain of antibody RFB4, provided that residues 100, 100A and 100B of CDR3 of the V H chain of said anti-CD22 antibody have an amino acid sequence selected from the group consisting of: THW, YNW, TTW, and STY and further provided that residue 100 of the V L chain of said anti-CD22 antibody is C and residue 44 of the V H chain of said anti-CD22 antibody is C, as the residues of the V L and V H chains are numbered in the column of FIG. 2 or FIG. 3 labeled “Kabat Numbering”.