Disulfide bond stabilized polypeptide compositions and methods of use
Provided herein are polypeptides comprising one or more non-native cysteine residues that form a disulfide bridge between non-native cysteines within the protein or between non-native cysteines of two monomers of the protein. Such modified human polypeptides are useful in treatment of genetic diseases via enzyme replacement therapy and/or gene therapy.
1. A gene therapy vector comprising a nucleic acid construct comprising: a nucleic acid encoding a stabilized form of a protein that is defective or deficient in a genetic disorder, the stabilized form comprising one or more non-native cysteine residues that form a disulfide bridge between non-native cysteines within the protein or between non-native cysteines of two monomers of the protein, wherein:
the protein comprises a stabilized α-galactosidase A (α-GAL) protein further comprising one or more pairs of non-native cysteine residues compared to the wildtype α-GAL sequence (SEQ ID NO:1), selected from the group consisting of: (i) D233C and I359C; and (ii) M51C and G360C; and
the gene therapy vector is a viral vector selected from the group consisting of an adenovirus vector, an adeno-associated virus vector, a retrovirus vector, a lentivirus vector, and a herpes virus vector.
2. The gene therapy vector of claim 1 , wherein the stabilized protein has a longer half-life at pH 7.4 compared to a corresponding protein without the non-native cysteines.
3. The gene therapy vector of claim 1 , wherein the stabilized-protein can replace a protein that is defective or deficient in the genetic disorder.
4. The gene therapy vector of 1, wherein the stabilized protein can reduce or slow one or more symptoms associated with the genetic disorder.
5. The gene therapy vector of 1, wherein the stabilized protein is more effective at reducing or slowing one or more symptoms of the genetic disorder, compared to a wildtype protein.
6. The gene therapy vector of claim 1 , wherein the viral vector genome comprises a recombinant AAV (rAAV) genome.
7. The gene therapy vector of claim 6 , wherein the rAAV genome comprises a self-complementary genome.
8. The gene therapy vector of claim 6 , wherein the rAAV genome comprises a first inverted terminal repeat and a second inverted terminal repeat.
9. The gene therapy vector of claim 6 , wherein the rAAV genome further comprises an SV40 intron and a poly-adenylation sequence.
10. The gene therapy vector of claim 6 , wherein the construct further comprises a nucleic acid sequence encoding an α-GAL protein, wherein the nucleic acid sequence is at least 85% identical to SEQ ID Nos: 7-12.
11. The gene therapy vector of claim 1 , wherein the construct further comprises a promoter sequence.
12. The gene therapy vector of claim 11 , wherein the promoter is a constitutive promoter or a tissue-specific promoter.
13. The gene therapy vector of claim 1 , wherein the construct further comprises one or more nucleic acid sequences selected from the group consisting of: a Kozak sequence, a cricket paralysis virus internal ribosomal entry sequence (CrPV IRES), a nucleic acid sequence encoding a linker, a nucleic acid sequence encoding a signal sequence, and a nucleic acid sequence encoding an Insulin-like Growth Factor 2 peptide.
14. A pharmaceutical composition comprising the gene therapy vector of claim 1 and a pharmaceutically acceptable excipient, carrier, or diluent.
15. The pharmaceutical composition of claim 14 , wherein the excipient is selected from the group consisting of saline, maleic acid, tartaric acid, lactic acid, citric acid, acetic acid, sodium bicarbonate, sodium phosphate, histidine, glycine, sodium chloride, potassium chloride, calcium chloride, zinc chloride, water, dextrose, N-methylpyrrolidone, dimethyl sulfoxide, N,N-dimethylacetamide, ethanol, propylene glycol, polyethylene glycol, diethylene glycol monoethyl ether, and surfactant polyoxyethylene-sorbitan monooleate.
16. The gene therapy vector of claim 1 , wherein the stabilized protein comprises a pair of non-native cysteine residues at D233C and I359C of SEQ ID NO:1.
17. The gene therapy vector of claim 1 , wherein the stabilized protein comprises a pair of non-native cysteine residues at M51C and G360C of SEQ ID NO:1.
18. The gene therapy vector of claim 16 , wherein the stabilized protein comprises the amino acid sequence of SEQ ID NO:5.
19. The gene therapy vector of claim 18 , wherein the stabilized protein comprises the amino acid sequence of SEQ ID NO:4.
20. The gene therapy vector of claim 1 , wherein the construct further comprises a nucleic acid sequence encoding an a-GAL protein, wherein the nucleic acid sequence comprises at least one of SEQ ID NO: 15 and SEQ ID NO: 16.