Receptor mediated label transfer assay

摘要

A new method for the detection of subpicogram amounts of soluble receptors and receptor-ligands is disclosed. The method is exceedingly sensitive and has been used to detect tumor necrosis factor in plasma samples. The technique takes advantage of the resolving power of polyacrylamide gel electrophoresis combined with specificity imparted by receptor-ligand interaction. Limitations imposed only by the affinity constant of interaction between ligand and receptor are circumvented by forming a covalent bond between the receptor and the ligand. The assay is in principle applicable to the detection of many protein hormones for which soluble receptors exist and is particularly suited to detection of proteins that engage multiple receptor subunits. The methods represent a major improvement over conventional methods for the assay of trace proteins to permit the specific detection of only a few hundred thousand active molecules.