VERSIONS OF Fc-REGION WITH ALTERED BINDING TO NEONATAL Fc-RECEPTOR (FcRn) FOR USE IN VETERINARY SCIENCE Russian patent published in 2024 - IPC C07K16/00 C07K16/24 C07K16/28 C07K19/00 C12P21/02 

FIELD: biotechnology.

SUBSTANCE: invention relates to biotechnology, specifically to polypeptides based on a variant of the Fc region of dog IgG, and can be used for recombinant production thereof. Disclosed are variant canine Fc IgG polypeptides containing at least one amino acid substitution relative to canine Fc IgG polypeptide of wild type, as well as fused polypeptides based thereon. Variant Fc IgG polypeptide is SEQ ID NO: 14, SEQ ID NO: 15, SEQ ID NO: 16, SEQ ID NO: 17, SEQ ID NO: 33, SEQ ID NO: 34, SEQ ID NO: 35, SEQ ID NO: 36, SEQ ID NO: 37, SEQ ID NO: 38, SEQ ID NO: 39, SEQ ID NO: 40, SEQ ID NO: 41, SEQ ID NO: 42, SEQ ID NO: 43, SEQ ID NO: 44, SEQ ID NO: 45, SEQ ID NO: 46, SEQ ID NO: 47, SEQ ID NO: 50, SEQ ID NO 51 or SEQ ID NO: 52.

EFFECT: invention enables to obtain a polypeptide which binds to a canine FcRn/B2M complex with high affinity at pH from 5,0 to 6,5 compared to a canine wild-type IgG Fc peptide.

8 cl, 16 dwg, 18 tbl, 23 ex