Purity >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie? Blue Staining. MW (observed): 78-121 kDa, reducing conditions. MW (theoretical): 44 kDa. The Recombinant Human ELFN1 His-tag Protein from R&D Systems is derived from CHO. The Recombinant Human ELFN1 His-tag Protein has been validated for the following applications: Bioactivity.