| abstract |
The present invention provides a chimeric antigen receptor (CAR) system comprising; (i) a receptor component comprising a antigen binding domain and a first binding domain; and (ii) a signalling component comprising a signalling domain and a second binding domain which binds the single domain binder of the first binding domain of the receptor component wherein either the first or second binding domains comprise a single domain binder, and wherein, binding of the first and second binding domains is disrupted by the presence of an agent, such that in the absence of the agent, the receptor component and the signalling component heterodimerize and binding of the antigen binding domain to antigen results in signalling through the signalling domain; whereas in the presence of the agent, the receptor component and the signalling component do not heterodimerize and binding of the antigen binding domain to antigen does not result in signalling through the signalling domain. |