For humans, IFN-α consists of a group of proteins that are greater than 85% homologous by amino acid sequence. A lot of individual human IFN-α subtypes have been identified and many have different properties. For the moment, we don’t know exactly why there are multiple IFN-α subtypes. A variety of studies suggested they possess overlapping but also unique sets of biological activities. Quantification of IFN is essential but usually methods don’t take account all IFN types. In this post, I would like to focus on a relevant ELISA kit to avoid this problem.