Figure 9. Prolonged binding of IL-4 to V50-IL-4Rα.
A. U937 clones expressing the I50- or V50-IL-4Rα were analyzed for expression of IL-4Rα by M1 staining or by IL-4 binding. Cells were treated with 10.0 ng/mL of murine IL-4 for 15 minutes at 4°C. The cells were isolated and stained for murine IL-4 bound to the receptors using the biotin rat anti-mouse IL-4 monoclonal antibody. B. U937 clones expressing the I50- or V50-IL-4Rα were treated with 10.0 ng/mL of murine IL-4 for 15 minutes. The cells were isolated and separated into three groups: (1) IL-4 treatment, (2) IL-4 removal, (3) 30 minutes post-IL-4 removal. The cells were stained for murine IL-4 bound to the polymorphic receptors using the biotin rat anti-mouse IL-4 monoclonal antibody.