METHODS FOR IDENTIFYING MEMBERS OF SPECIFIC BINDING PAIRS

摘要

The present invention provides a method for identifying members of specific binding pairs comprising (a) providing a mammalian cell which is susceptible to apoptosis upon exposure to a stimulus, (b) expressing in the cell a putative first binding pair member fused to an apoptosis inhibitor, or the signalling portion thereof, such that the putative first binding pair member is displayed on the surface of the cell (e.g. WEHI 231 cells), (c) exposing the cell to an agent capable of inducing apoptosis in such a cells in which the apoptosis inhibitor is not activated, and (d) contacting the cell with a putative second binding pair member, wherein members of specific binding pairs are identified by the binding of the second pair member to the first binding pair member, such that the apoptosis inhibitor is activated to inhibit apoptosis of the cell which expresses the first binding pair member. Preferably, the first binding members are expressed as fusion proteins with the signalling portion of CD40. In a preferred embodiment, the putative first binding pair member is an antibody or antigen-binding fragment thereof (e.g. scFv) and the putative second binding pair member is an antigen, or vice-versa.