Expression of recombinant extracellular domain of the type II transforminggrowth factor-ss receptor: Utilization in a modified enzyme-linked immunoabsorbent assay to screen TGF-ss agonists and antagonists

TGF-beta is a ubiquitous protein that exhibits a broad spectrum of biologic al activity. The prokaryotic expression and purification of the extracellul ar domain of the type II TGF-beta receptor (T betaR-II-ED), without the nee d for fusion protein cleavage and refolding, is described. The recombinant T betaR-II-ED fusion protein bound commercially available TGF-beta1 and dis played an affinity of 11.1 nM. In a modified ELISA, receptor binding to TGF -beta1 was inhibited by TGF-beta3. The technique lends itself to high-throu ghput screening of combinatorial libraries for the identification of TGF-be ta agonists and antagonists and this, in turn, may have important therapeut ic implications, (C) 2001 Academic Press.