Cell lines and their use in encapsulated cell biodelivery
View Patent ↗The present invention relates to generation of cell lines expressing recombinant proteins for use in naked and encapsulated cell biodelivery of secreted therapeutic molecules. In one embodiment the cell line is human. In another aspect of the invention the transposon system is used for generating a cell line for secretion of a biologically active polypeptide.
1. A method for manufacturing a secreted recombinant protein in vitro comprising:
a) culturing human contact-inhibited ARPE-19 cells comprising:
i) between 3 and 10 Sleeping Beauty transposons, said one or more transposons each comprising at least two terminal inverted repeats, said terminal inverted repeats being substrates for a transposase,
ii) a heterologous expression construct encoding said secreted recombinant protein, said heterologous expression construct being located between said two terminal inverted repeats, and
iii) said one or more transposons integrated into genome of said human contact-inhibited cells;
b) encapsulating said human contact-inhibited cells within a capsule comprising a semipermeable outer membrane and an inner core, said inner core comprising said human contact-inhibited cells suspended in a liquid medium;
c) said human contact-inhibited cells forming a composition in said liquid medium having a high and stable expression level of said secreted recombinant protein for at least a six month period without requiring the presence of a selection pressure compared to said human contact-inhibited cells generated without a transposase; and
d) recovering said secreted recombinant protein from said liquid medium.
2. The method of claim 1 , wherein the ARPE-19 cells secrete at least 200 ng/10 6 cells/24 hrs. of said recombinant protein.
3. The method of claim 1 , wherein said Sleeping Beauty variant is selected from the variants of SB10X comprising the amino acid sequence differing from SEQ ID NO 7 by 1 to 20 amino acids including at least one of the following mutations or groups of mutations selected from the group consisting of K14R; K13D; K13A; K30R; K33A; T83A; I100L; R115H; R143L; R147E; A205K/H207V/K208R/D210E; H207V/K208R/D210E; R214D/K215A/E216V/N217Q; M243H; M243Q; E267D; T314N; and G317E.
4. The method of claim 3 , wherein said Sleeping Beauty variant is variant 27 comprising the amino acid sequence disclosed in SEQ ID NO 8.
5. The method of claim 3 , wherein the Sleeping Beauty variant is variant 28 comprising the amino acid sequence disclosed in SEQ ID NO 9.
6. The method of claim 1 , wherein the expression construct is under the control of a constitutive promoter.
7. The method of claim 1 , wherein the capsule comprises between 10,000 and 250,00 cells per μL of capsule volume.
8. The method of claim 1 , wherein the inner core comprises a matrix for the cells disposed within the semi-permeable membrane.
9. The method of claim 8 , wherein the matrix is selected from reticulate foam scaffold, yarn, filaments, mesh, and braid.
10. The method of claim 1 , wherein the semi-permeable outer membrane is microporous.
11. The method of claim 1 , wherein the semi-permeable outer membrane has a molecular weight cutoff of 1000 κDa or less.
12. The method of claim 1 , wherein the recombinant protein is selected from growth factors, growth factor receptors, antibodies, neuropeptides, neurotransmitter synthesizer proteins, trophic factors, interleukins, hormones, and enzymes.
13. The method of claim 12 , wherein the protein is selected from basic fibroblast growth factor (bFGF), acid fibroblast growth factor, epidermal growth factor, transforming growth factor a, transforming growth factor β, nerve growth factor, insulin like growth factor, platelet derived growth factor, glia cell lined-derived neurotrophic factor, neurturin, persephin, Neublastin (Artemin), brain derived neurotrophic factor, ciliary neurotrophic factor, tryophotin, activin, thyrotropin releasing hormone, bone morphogenic protein, macrophage inflammatory proteins, heparin sulfate, amphiregulin, retinoic acid, tumor necrosis factor a, fibroblast growth factor receptor, and epidermal growth factor receptor.
14. The method of claim 12 , wherein the antibody is selected from human antibodies, humanized antibodies, chimeric antibodies, antigen binding fragments of antibodies, Fv, scFv, Fab, Fab′ or F(ab) 2 , IgA, IgM, antibodies and diabodies.
15. The method of claim 1 , wherein the protein is produced without the use of antibiotics.
16. The method of claim 1 , further comprising down-stream processing of the recovered protein.
17. The method of claim 1 , wherein said cells expressing said secreted recombinant protein are a monoclonal cell line.