Patent ID: 11958912
Assignee: HOFFMANN-LA ROCHE, INC.
Field: Measurement (Instruments)
Classification: CPC C  G | IPC C  G

Claim 0:
1. A method for determining the binding interaction with a multimeric antigen of an antibody of the human class G immunoglobulin, subclass 1 (IgG1) comprising the following steps:
1) determining the binding affinity of the antibody for the multimeric antigen,
2) incubating a mixture comprising the antibody, the multimeric antigen and lysine-gingipain of Porphyromonas gingivalis at a pH of 7.5 to 8.5, in the presence of a reducing agent, at a temperature of 30° C. to 42° C., for a time of 10 minutes to 240 minutes to cleave the antibody into antigen-binding fragments (Fabs) and a crystallizing fragment (Fc)-region, whereby the concentration of the antibody prior to said cleaving is higher than the concentration of the antigen, and
determining the binding affinity of the Fabs of the antibody for the multimeric antigen,

and
3) determining the binding affinity of the antibody to the multimeric antigen to be affinity-driven if the binding affinity determined in step 1) and 2) is comparable and to be avidity-driven if the binding affinity determined in both step 1) and 2) is different;
wherein the binding affinity is determined in solution using an enzyme-linked immunosorbent assay (ELISA) or a surface plasmon resonance method; and
wherein the binding affinities determined in steps 1 and 2 of the antibody to the multimeric antigen are comparable if the binding affinities determined in both steps differ by a factor of 2 or less, wherein the smaller value is used as basis for the calculation; and is different if the binding affinities determined in both steps differ by more than a factor of 2, wherein the smaller value is set to 100%.