Fig. 1

Characteristics of M802. (a) Schematic diagram of M802, which consisted of a monovalent unit and a single chain unit. The monovalent unit consisted of M802H and M802 L conjugated by a disulfide bond. The single chain unit was L2KVH-linker-L2KVL-Fc structure. Two disulfide bonds were formed between the monovalent unit and the single chain unit. (b) SDS-PAGE of M802 from 293F cells purified by protein A affinity and ion-exchange chromatography. In the reducing SDS-PAGE, the single chain unit and heavy chain of the monovalent unit (M802H) showed slightly different electrophoretic mobility. (c) Analytical size-exclusion chromatograms of purified M802 described in (b), and the purity of this sample was more than 98%. (d) Isoelectric focusing of Herceptin and M802. For M802, two main charge variant bands that migrated above PI 8.0 and below Herceptin. (e) Mass spectrum for molecular weight determination of the intact BsAb and chains under reducing conditions. The molecular weight of M802H was 50.628 KDa, M802 L was 23.443 KDa, L2K single chain was 53.539 KDa, and intact M802 was 127.758 KDa