Rat (and mouse) monoclonal antibodies. VIII. ELISA measurement of Ig production in mouse hybridoma culture supernatants.

We describe a rat monoclonal antibody (MAb)-based solid-phase immunoenzymometric assay for the quantification of mouse hybridoma culture supernatant immunoglobulins (Igs). This assay involves the use of two rat MAbs, LO-MK-1 and LO-MK-2, which bind distinct mouse kappa light chain epitopes expressed by all murine kappa Igs. The assay permits reliable measurement of all murine kappa IgG subclasses in the 2-120 ng/ml range and murine kappa IgM class in the 2-30 ng/ml range. The intra- and interassay coefficients of variation in the measurement of Ig in mouse hybridoma culture supernatants averaged 7.5% and 5% respectively. The assay is simple, reproducible, rapid and does not require specific equipment. It is of potential value to all laboratories engaged in hybridoma technology.