Targeted replacement of endogenous T cell receptors
Provided herein are methods and compositions for editing the genome of a human T cell. In some embodiments, a heterologous T cell receptor (TCR)-β chain and a heterologous TCR-α chain are inserted into exon 1 of a TCR subunit constant gene in the genome of the T cell.
1. A method of treating a subject having a cancer that expresses a target antigen, comprising:
administering to the subject having the cancer a modified primary human T cell comprising: at least one nucleic acid sequence comprising at least one heterologous gene non-virally inserted into one or both of:
an endogenous T cell receptor alpha subunit constant gene (TRAC); and
an endogenous T cell receptor beta subunit constant gene (TRBC),
wherein the at least one heterologous gene encodes at least one antigen-specific receptor that specifically binds the target antigen expressed by the cancer, and wherein the at least one heterologous gene comprises at least one of: (1) a variable region of a heterologous human T cell receptor alpha (TCR-a) chain gene and (2) a variable region of a heterologous human T cell receptor beta (TCR-b) chain gene.
2. The method of claim 1 , wherein the modified human T cell does not comprise a viral vector.
3. The method of claim 1 , wherein the at least one nucleic acid sequence is at least 1.5 kb in size.
4. The method of claim 1 , wherein the at least one nucleic acid sequence is non-virally inserted into an exon of the T cell receptor alpha subunit constant gene (TRAC) or into an exon of the T cell receptor beta subunit constant gene (TRBC).
5. The method of claim 1 , wherein the at least one nucleic acid sequence is at least 500 bp in size.
6. The method of claim 1 , wherein the at least one heterologous gene comprises at least one of:
(1) a) a variable region of a heterologous T cell receptor alpha (TCR-α) chain or b) a variable region and constant region of the heterologous TCR-α chain; and
(2) a) a variable region of a heterologous T cell receptor beta (TCR-β) chain or b) a variable region and constant region of the heterologous TCR-β chain.
7. The method of claim 6 , wherein the at least one heterologous gene comprises each of:
(1) the a) variable region of the heterologous TCR-α chain or b) variable region and constant region of the heterologous TCR-α chain; and
(2) the a) variable region of the heterologous TCR-β chain or b) variable region and constant region of the heterologous TCR-β chain.
8. The method of claim 7 , wherein one or more coding sequences for the heterologous TCR-α chain and the heterologous TCR-β chain are linked by a linker sequence or a multicistronic element.
9. The method of claim 8 , wherein the linker sequence is a cleavable linker sequence that is cleaved to generate the heterologous TCR-α chain gene and the heterologous TCR-β chain gene.
10. The method of claim 8 , wherein the heterologous gene encodes the TCR-α chain and the heterologous TCR-β chain and wherein the heterologous gene is inserted into TRAC.
11. The method of claim 1 , wherein the at least one heterologous gene is non-virally inserted into an endogenous TRAC, wherein the at least one heterologous gene comprises each of:
(1) a) a variable region of the heterologous TCR-α chain or b) a variable region and constant region of the heterologous TCR-α chain; and
(2) a) a variable region of the heterologous TCR-β chain or b) a variable region and constant region of the heterologous TCR-β chain,
wherein the heterologous TCR-α chain and the heterologous TCR-β chain are operably linked by a cleavable linker sequence that is cleaved to generate the heterologous TCR-α chain and the heterologous TCR-β chain, and wherein the heterologous TCR-α chain and the heterologous TCR-β form an antigen-specific T cell receptor (TCR) that recognizes the target antigen expressed by the cancer.
12. The method of claim 1 , wherein expression of the at least one heterologous gene is under the control of an endogenous promoter.
13. The method of claim 1 , wherein the modified human T cell is a CD8+ T cell or a CD4+ T cell.
14. The method of claim 13 , wherein the CD8+ T cell or CD4+ T cell is an effector T cell or a naïve T cell.
15. The method of claim 1 , wherein a primary human T cell is obtained from the subject having the cancer and modified to comprise the at least one nucleic acid sequence comprising at least one heterologous gene prior to administration of the modified primary human T cell to the subject.
16. The method of claim 1 , further comprising culturing the modified human T cell under conditions that allow for expression of the at least one heterologous gene encoding the receptor that specifically binds the target antigen expressed by the cancer.
17. The method of claim 16 , further comprising culturing the modified human T cell under conditions effective for expanding the modified human T cell.
18. The method of claim 1 , further comprising purifying the modified human T cell(s) that express the receptor.