Preparation of biotinylated anti-cytokine monoclonal antibodies

ObjectiveTo explore a method of preparation for biotinylated monoclonal antibodies. MethodsRat anti-mouse IL-5, IL-4 and IFN-γ were purified by ultra filtration, precipitated with saturated ammonium sulfate further purified by chromatography with the protein G-sepharose affinity column from the hybridoma cell culture supernatants. We added 80 μg of the biotinylation reagent per 1 mg of the monoclonal antibody, and incubated them at room temperature for 60 min. After that, we applied the monoclonal antibody sample to the Sephadex G-25 column and got the purified biotinylated monoclonal antibody. The antibodies were tested the activities through the Avidin-biotin ELISA. ResultsThe results showed that the antibodies kept high biological activities and sensitivities in detecting the sera from IL-5 transgenic mice and non-transgenic mice by ELISA. ConclusionThe method is simple and stable. [