Fig. 4.

Determination of an apparent association constant by Langmuir plot. Antigens were rIFN α-2b (▲), IFN α-2b (◼) and cIFN α-2b gene (●). Immune complexes were prepared by incubating 100 mg of IgG with varying amount of different interferons (0-100 mg) in an assay volume of 500 ml for 2 h at room temperature and overnight at 4°C. The binding data were analyzed for antibody affinity as described in Material and methods. #Significantly higher binding than IFN α-2b (p < 0.05) and IFN α-2b gene (p < 0.001)