| 摘要 |
Among N-glycoside-linked sugar chains which are bound to the Fc region of an antibody, sugar chains which are bound to Asn at position 297 relates to the activity and stability of the antibody in blood, but there is a possibility that extra sugar chains bound to the amino acid residues at positions other than 297 have influences upon the antibody constant region-mediated activity and a possibility of causing a problem of uniformity as a therapeutic antibody preparation. Accordingly, among N-glycoside-linked sugar chains which bind to the Fc region of the antibody, a method for controlling extra sugar chains which are bound to Asn residues at positions other than position 297 according to the EU index is required. The present invention provides an antibody variant composition, comprising amino acid residues of an Asn-X-Ser/Thr (X represents an amino acid residue other than Pro) sequence at positions other than positions 297 to 299 according to the EU index in an Fc region of a human IgG antibody, in which at least one amino acid substitution selected from an amino acid substitution of Asn to other amino acid residue, an amino acid substitution of X to Pro and an amino acid substitution of Ser/Thr to other amino acid residue is carried out, and a fragment of the antibody variant composition. |
