Nuclease-mediated genome editing of primary cells and enrichment thereof
In certain aspects, the present invention provides methods for inducing a stable gene modification of a target nucleic acid via homologous recombination in a primary cell, such as a primary blood cell and/or a primary mesenchymal cell. In certain other aspects, the present invention provides methods for enriching a population of genetically modified primary cells having targeted integration at a target nucleic acid. The methods of the present invention rely on the introduction of a DNA nuclease such as a Cas polypeptide and a homologous donor adeno-associated viral (AAV) vector into the primary cell to mediate targeted integration of the target nucleic acid. Also provided herein are methods for preventing or treating a disease in a subject in need thereof by administering to the subject any of the genetically modified primary cells or pharmaceutical compositions described herein to prevent the disease or ameliorate one or more symptoms of the disease.
1. A method for producing a stable integration of a polynucleotide into a genome of one or more primary cells of a population of primary cells via homologous recombination, the method comprising:
introducing into the one or more primary cells:
(a) a modified single guide RNA (sgRNA) comprising a first nucleotide sequence that is complementary to a target nucleic acid sequence in the genome of the one or more primary cells and a second nucleotide sequence that interacts with a CRISPR-associated Cas polypeptide, wherein the first nucleotide sequence, the second nucleotide sequence, or both comprise a modified nucleotide;
(b) the Cas polypeptide, an mRNA encoding the Cas polypeptide, or a recombinant expression vector comprising a nucleotide sequence encoding the Cas polypeptide, wherein the modified sgRNA guides the Cas polypeptide to the target nucleic acid sequence; and
(c) an adeno-associated viral (AAV) vector comprising the polynucleotide,
wherein the Cas polypeptide cleaves the target nucleic acid sequence, thereby generating a double-strand break in the target nucleic acid sequence,
wherein the polynucleotide is integrated into the double-strand break in the target nucleic acid sequence, thereby producing the stable integration of the polynucleotide into the genome of the one or more primary cells, and
wherein the polynucleotide is integrated into the genome of greater than 10% of primary cells in the population of primary cells.
2. The method of claim 1 , wherein the one or more primary cells are primary blood cells, primary mesenchymal cells, or a combination thereof.
3. The method of claim 1 , wherein the AAV vector is selected from the group consisting of: AAV1, AAV2, AAV3, AAV4, AAV3, AAV5, AAV6, AAV7, AAV8, AAV9, AAV10, AAV11 and AAV12.
4. The method of claim 1 , wherein the AAV vector is an AAV6 vector.
5. The method of claim 1 , further comprising introducing a second AAV vector comprising a second polynucleotide for integration into the one or more primary cells.
6. The method of claim 5 , wherein the second polynucleotide is integrated into a second nucleic acid sequence in the genome of the one or more primary cells, wherein the second nucleic acid sequence is different from the target nucleic acid sequence.
7. The method of claim 5 , wherein the second polynucleotide is integrated into the target nucleic acid sequence in the one or more primary cells.
8. The method of claim 1 , wherein the Cas polypeptide is a Cas9 polypeptide.
9. The method of claim 1 , wherein the modified sgRNA and the Cas polypeptide are incubated together to form a ribonucleoprotein (RNP) complex prior to introducing into the one or more primary cells.
10. The method of claim 9 , wherein the RNP complex and the AAV vector are sequentially introduced into the one or more primary cells.
11. The method of claim 10 , wherein the RNP complex is introduced into the one or more primary cells before the AAV vector.
12. The method of claim 1 , wherein the modified nucleotide is selected from the group consisting of: a 2′-O-methyl nucleotide, a 2′-O-methyl 3′-phosphorothioate nucleotide, and a 2′-O-methyl 3′-thioPACE (MSP) nucleotide.
13. The method of claim 1 , wherein the modified nucleotide comprises a 2′-O-methyl 3′-phosphorothioate nucleotide.
14. The method of claim 1 , wherein a 5′ end, a 3′ end, or a combination thereof of the modified sgRNA comprises the modified nucleotide.
15. The method of claim 1 , wherein the one or more primary cells are mammalian cells.
16. The method of claim 1 , wherein the one or more primary cells are human cells.
17. The method of claim 1 , wherein the method is ex vivo.
18. The method of claim 1 , wherein the stable integration of the polynucleotide into the genome of the one or more primary cells is determined by sequencing a portion of a genomic DNA of the one or more primary cells after introducing the AAV vector.
19. The method of claim 1 , wherein the polynucleotide is integrated into the genome of greater than 20% of primary cells in the population of primary cells.