TRANSCRIPTION SYSTEM

1 . A transcription system which comprises:

(a) a docking component which comprises a first binding domain; and

(b) a transcription control component which comprises a transcription factor and a second binding domain which binds the first binding domain of the docking component

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 docking component and the transcription control component heterodimerize.

2 . A transcription system according to claim 1 , wherein

the docking component also comprises a membrane localisation domain; and

the transcription component also comprises a nuclear localisation signal

such that when the transcription system is expressed in a cell, in the absence of the agent the transcription component is held on the intracellular side of the plasma membrane; whereas in the presence of the agent the transcription component dissociates from the docking component and translocates to the nucleus where the transcription factor binds DNA and regulates the transcription of a gene.

3 . A transcription system according to claim 1 , wherein

the docking component also comprises a nuclear localisation signal; and

the transcription component also comprises a nuclear export signal

such that when the transcription system is expressed in a cell, in the absence of the agent the transcription component is held in the nucleus where the transcription factor binds DNA and regulates the transcription of a gene; whereas in the presence of the agent the transcription component dissociates from the docking component and translocates to the cytoplasm.

4 .- 10 . (canceled)

11 . A transcription system according to claim 1 , wherein the transcription factor prevents or reduces T-cell differentiation and/or exhaustion when expressed in a T-cell.

12 .- 22 . (canceled)

23 . A nucleic acid construct encoding a transcription system according to claim 1 , which comprises

(a) a first nucleic acid sequence encoding a docking component which comprises a first binding domain; and

(b) a second nucleic acid sequence encoding a transcription control component which comprises a transcription factor and a second binding domain which binds the first binding domain of the docking component

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 docking component and the transcription control component heterodimerize.

24 . (canceled)

25 . A nucleic acid construct according to claim 23 , which comprises a third nucleic acid sequence encoding a chimeric antigen receptor.

26 .- 27 . (canceled)

28 . A kit of nucleic acid sequences which comprises

(a) a first nucleic acid sequence encoding a docking component which comprises a first binding domain; and

(b) a second nucleic acid sequence encoding a transcription control component which comprises a transcription factor and a second binding domain which binds the first binding domain of the docking component

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 docking component and the transcription control component heterodimerize.

29 . (canceled)

30 . A vector which comprises a nucleic acid construct according to claim 23 .

31 . A kit of vectors which comprises (a) a first vector which comprises a first nucleic acid sequence encoding a docking component which comprises a first binding domain; and

(b) a second vector which comprises a second nucleic acid sequence encoding a transcription control component which comprises a transcription factor and a second binding domain which binds the first binding domain of the docking component

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 docking component and the transcription control component heterodimerize.

32 . (canceled)

33 . A cell which comprises a transcription system according to claim 1 .

34 . A cell according to claim 33 which expresses a chimeric antigen receptor.

35 . A method for making a cell according to claim 33 , which comprises the step of introducing: a nucleic acid construct, a kit of nucleic acid sequences, a vector, or a kit of vectors, into a cell.

36 . (canceled)

37 . A pharmaceutical composition comprising a plurality of cells according to claim 33 .

38 . A method for treating and/or preventing a disease, which comprises the step of administering a pharmaceutical composition according to claim 37 to a subject.

39 .- 42 . (canceled)

43 . A method for regulating the transcription of a gene in a cell according to claim 33 , which comprises the step of administering the agent to the cell in vitro.

44 . A method for regulating the transcription of a gene in a cell according to claim 33 in vivo in a subject, which comprises the step of administering the agent to the subject.

45 . (canceled)

46 . A method for preventing or reducing T cell differentiation or exhaustion in a cell comprising a transcription system according to claim 1 , which comprises the step of administering the agent to the cell in vitro.

47 . A method for preventing or reducing T cell differentiation or exhaustion in a cell comprising a transcription system according to claim 1 in vivo in a subject, which comprises the step of administering the agent to the subject.

48 . (canceled)

49 . A composition which comprises a plurality of cells according to claim 33 together with the agent which disrupts binding of the first and second binding domains.