Developing novel agonists of cytokine receptors by targeting receptor pre-clusters

Members of the tumor necrosis factor receptor superfamily (TNFRSF) regulate proliferation of immune cells or induce programmed cell death. Developing antibodies to selectively activate or inhibit these receptors is of tremendous implication in the treatment of cancer or autoimmune diseases. In earlier study, we made an unexpected finding that, for several members of the TNFRSF, there exists a defined autoinhibitory, pre-clustered state formed by the receptor ectodomain, and that proteolytic removal of the ectodomain led to full receptor activation. Recently, we have obtained direct structural evidence of such preligand cluster, raising the prospect of developing new agonistic antibodies that act by disrupting the receptor preligand association. In this pilot research, we propose to develop agonistic single-domain antibodies (sdAbs) that specifically activate TNF receptors by disrupting the preligand association for enhancing antitumor activity of T cells, using a combination of Yeast Display and the SPLANDID antigen presentation technology.