Measurement of Interleukin-2 by Bioassay

Bioassays are used to determine the presence and concentration of biologically active cytokines by exploiting the different activities they induce, such as cellular proliferation, chemotaxis, or cytotoxicity. These assays often use established cell lines that depend for their continued growth and survival on the presence of particular cytokine(s). The detection of the cytokine may be made directly using the cell line of choice or via a second cell line that is directly dependent on the activities or properties of the first cell line. These assays are called conversion assays. Bioassays remain a simple and relatively inexpensive method for cytokine quantification; they require no specialized equipment, and, in comparison with enzyme-linked immunosorbent assay (ELISA) methods, they are relatively easy to set up in a cell culture laboratory.