Chimeric antigen receptors comprising bcma-specific fibronectin type iii domains and uses thereof

Abstract

BCMA-specific fibronectin type III (FN3) domains, BCMA-targeting chimeric antigen receptors (CARs) comprising the FN3 domains, and engineered BCMA-targeting immune cells expressing the CARs are described. Also described are nucleic acids and expression vectors encoding the FN3 domains and the CARs, recombinant cells containing the vectors, and compositions comprising the engineered immune cells. Methods of making the FN3 domains, CARs, and engineered immune cells, and methods of using the engineered immune cells to treat diseases including cancer are also described.

1 - 13 . (canceled) 
     
     
         14 . An isolated polynucleotide encoding a chimeric antigen receptor (CAR) comprising:
 an extracellular domain having an FN3 domain that binds to BCMA;   a transmembrane domain; and   an intracellular signaling domain.   
     
     
         15 . The isolated polynucleotide of  claim 14 , wherein the FN3 domain comprises an amino acid sequence that is at least 80% identical to SEQ ID NO: 1; and wherein the FN3 domain binds to a human BCMA with a KD less than 1×10 −6  M as determined by using surface plasmon resonance. 
     
     
         16 . The isolated polynucleotide of  claim 14 , wherein the FN3 domain comprises the amino acid sequence of SEQ ID NO: 7. 
     
     
         17 . The isolated polynucleotide of  claim 14 , wherein the FN3 domain comprises an amino acid sequence that is at least 90% identical to any one of SEQ ID NOs: 8-44 and 58-145. 
     
     
         18 . The isolated polynucleotide of  claim 14 , wherein the FN3 domain comprises the amino acid sequence of any one of SEQ ID NOs: 8-44 and 58-145. 
     
     
         19 . The isolated polynucleotide of  claim 14 , wherein the CAR further comprises a signal peptide at the amino terminus. 
     
     
         20 . The isolated polynucleotide of  claim 19 , wherein the CAR further comprises a hinge region connecting the extracellular domain and the transmembrane domain. 
     
     
         21 . The isolated polynucleotide of  claim 20 , wherein the hinge region comprises an amino acid sequence that is at least 90% identical to SEQ ID NO: 3. 
     
     
         22 . The isolated polynucleotide of  claim 21 , wherein the hinge region comprises the amino acid sequence of SEQ. ID NO: 3. 
     
     
         23 . The isolated polynucleotide of  claim 14 , wherein the transmembrane domain comprises an amino acid sequence that is at least 90% identical to SEQ ID NO: 4. 
     
     
         24 . The isolated polynucleotide of  claim 23 , wherein the transmembrane domain comprises the amino acid sequence of SEQ ID NO: 4. 
     
     
         25 . The isolated polynucleotide of  claim 14 , wherein the intracellular signaling domain comprises a co-stimulatory domain having an amino acid sequence that is at least 90% identical to SEQ ID NO: 5, and a primary signaling domain having an amino acid sequence that is at least 90% identical to SEQ ID NO: 6. 
     
     
         26 . The isolated polynucleotide of  claim 25 , wherein the intracellular signaling domain comprises a co-stimulatory domain comprising the amino acid sequence of SEQ ID NO: 5, and a primary signaling domain comprising the amino acid sequence of SEQ ID NO: 6. 
     
     
         27 . The isolated polynucleotide of  claim 14 , comprising:
 the extracellular domain comprising the amino acid sequence of one of SEQ ID NOs: 8-44 and 58-145;   a hinge region comprising the amino acid sequence of SEQ ID NO: 3;   the transmembrane domain comprising the amino acid sequence of SEQ ID NO: 4; and   the intracellular signaling domain comprising the amino acid sequence of SEQ ID NO: 5 and the amino acid sequence of SEQ ID NO: 6.   
     
     
         28 . A vector comprising the polynucleotide of  claim 14 . 
     
     
         29 . A host cell comprising the polynucleotide of  claim 14 . 
     
     
         30 . A polypeptide encoded by the polynucleotide of  claim 14 .