Cell culture methods involving HDAC inhibitors or rep proteins
The invention relates to methods of culturing cells, generating cell lines, and delivering polynucleotides to cells involving the use of HDAC inhibitors and/or adeno-associated virus (AAV) rep proteins.
1. A method of developing a stable cell line comprising a recombinant AAV (rAAV) vector sequence stably integrated into chromosome 19 for producing rAAV, the method comprising:
a) providing a rAAV vector comprising the rAAV vector sequence and a rep mRNA selected from the group consisting of rep68 mRNA, rep78 mRNA, and a combination thereof to a HeLa cell culture;
b) culturing the HeLa cell culture under conditions that allow for integration of the rAAV vector into the HeLa cell genome;
c) identifying a HeLa cell that contains the rAAV vector sequence integrated into chromosome 19 of the HeLa cell genome; and
d) culturing the mammalian cell under conditions that allow for generation of a cell line that produces rAAV,
wherein the rAAV produced by the cell line is at a titer of at least 8.5×10 10 GC/ml when the HeLa cell culture of d) is cultured for at least four days.
2. The method of claim 1 , wherein the delivering of the rAAV vector and the rep mRNA is performed using electroporation, chemical-based transfection, microinjection, or cell squeezing.
3. The method of claim 2 , wherein the chemical-based transfection comprises exposure to lipids, calcium phosphate, cationic polymers, DEAE-dextran, or activated dendrimers.
4. The method of claim 1 , wherein the delivering of the rAAV vector and the rep mRNA is performed using magnetic beads or nanoparticles.
5. The method of claim 1 , wherein the rAAV vector sequence is integrated into the HeLa cell genome at a 2-kb region on the long arm of chromosome 19 (19q13.3-qter).
6. The method of claim 1 , wherein the amount of rep mRNA provided to the HeLa cell is between 0.75 μg to 1 μg per 10 6 cells.
7. The method of claim 1 , wherein the rAAV produced by the HeLa cell line is at a titer of about 8.85×10 10 GC/ml to about 1.4 to 10 11 GC/ml.
8. A stable HeLa cell line generated using the method of claim 1 .
9. A plurality of rAAV particles produced by the stable HeLa cell line developed using the method of claim 1 .
10. The method of claim 1 , wherein the HeLa cell culture is a HeLa S3 cell culture.