FIELD: medicine.
SUBSTANCE: method for in vitro determination of presence and/or concentration of the binding partner of the multispecific binder in which the binding partner can be specifically linked to the first binding region of the multispecific binder comprising the steps of: incubation of a sample comprising a binding partner and a multispecific binder with a monospecific binder that specifically binds to the second multispecific binding region of the multispecific binder different from the first binding region. Elimination from the sample of the monospecific binder-multispecific binder complex prior to determination of the presence or concentration of the free binding partner. And determination of binding partner concentration in the sample, from which the multispecific binder is eliminated. The group of inventions also relates to the use of an anti-idiotype antibody that specifically binds to the second binding region of the multispecific antibody in the above method.
EFFECT: use of this group of inventions allows to eliminate the binding partner that is specifically associated with the multispecific binder from the sample, prior to determination of the presence or concentration of the free binding partner.
35 cl, 7 dwg
