Anti-soluble interleukin-2R alpha combinations measure different epitopes: comparison between different anti-sIL-2R alpha antibody combinations and a newly developed in-house sIL-2R alpha sandwich ELISA.

Cytokines are a group of low molecular weight glycoproteins important in cellular signaling for various responses such as activation and proliferation. They separate the cellular responses into Th1 and Th2 pathways, where each pathway releases its own cytokine group. Interleukins are an important section of the cytokine group and consist of a number of members with their respective receptors such as interleukin-2 and interleukin-2 receptor (IL-2 and IL-2R, respectively). In this study, a soluble interleukin-2 receptor alpha (sIL-2R alpha) sandwich ELISA was developed and tested with different samples. This method was compared with other mono- and polyclonal antibodies that measure sIL-2R alpha molecule using the same subjects and recombinant sIL-2R alpha. The results showed that different antibody combinations measure different epitopes on the receptor molecule.