METHODS OF RENATURATION OF RECOMBINANT PROTEINS
The present invention provides large-scale methods for renaturation of proteins comprising adding a solution of denatured, chemically modified or reduced proteins to a refolding buffer containing sulfate derived from H 2 SO 4 and/or MgSO 4 in the presence of guanidine. The present invention further provides methods of isolating a refolded protein at a concentration of about 0.4 to 3.0 gm/L by using a hydrophobic interaction chromatography (HIC) column.
1 . (canceled)
2 . (canceled)
3 . A method of isolating a refolded protein at a concentration of about 0.4 to 3 gm/L comprising:
a) loading a pH-adjusted protein solution to a hydrophobic interaction chromatography (HIC) column; and
b) eluting the protein with an elution buffer.
4 . A method for large-scale renaturation of proteins comprising adding to a refolding buffer a protein solution of about 12 to 20 gm/L of denatured, chemically modified or reduced protein in the presence of guanidine, wherein the refolding buffer comprises MgSO 4 in a Tris-base/Tris-HCl system.
5 . The method of claim 4 , wherein the refolding buffer comprises 0.2 M to 0.6 M MgSO 4 , 0.1 M to 0.6 M Tris Base, 0.7 M to 1.4 M Tris HCl, 2 mM to 7 mM EDTA, and 0.5 mM to 2 mM cysteine.
6 . (canceled)
7 . The method of claim 5 , wherein the refolding buffer further comprises 0.1 mM to 0.4 mM beta-mercaptoethanol.
8 . The method of claim 4 , wherein the refolding buffer further comprises 5%-20% sucrose.
9 . (canceled)
10 . (canceled)
11 . The method of claim 4 , wherein the addition of the protein occurs via pulsed dilution.
12 . The method of claim 11 , wherein the protein is added in 1 to 3 dilutions with 0 to 4 hours between dilutions.
13 . (canceled)
14 . The method of claim 4 , wherein the protein solution is diafiltered with 1 to 10 diavolumes of a diafiltration buffer prior to addition to the refolding buffer.
15 . (canceled)
16 . The method of claim 14 , wherein the diafiltration buffer comprises 3 M to 7 M guanidine.
17 . The method of claim 16 , wherein the diafiltration buffer further comprises 25 mM to 75 mM Tris, and 1 mM to 7 mM EDTA, at pH 7.0 to 9.0.
18 - 21 . (canceled)
22 . The method of claim 4 , further comprising recovering the protein via hydrophobic interaction chromatography (HIC).
23 . The method of claim 22 , wherein the pH is lowered to about 2.1 to 5.8 prior to HIC.
24 . (canceled)
25 . The method of claim 4 , wherein the protein solution contains about 20 gm/L of protein.
26 - 29 . (canceled)
30 . A method for large-scale renaturation of proteins comprising:
a) diafiltering a denatured, chemically modified, or reduced protein with 1 to 10 diavolumes of a diafiltration buffer, wherein the diafiltration buffer comprises guanidine;
b) concentrating the diafiltered protein to about 12 to 20 gm/L; and
c) adding the concentrated protein via pulsed dilution to a refolding buffer, wherein the refolding buffer comprises MgSO 4 in a Tris-base/Tris-HCl system.
31 . The method of claim 30 , wherein the diafiltration buffer comprises 3 M to 7 M guanidine, 25 mM to 75 mM Tris, and 1 mM to 7 mM EDTA, at pH 7.0 to 9.0.
32 - 35 . (canceled)
36 . The method of claim 31 , wherein the refolding buffer comprises 0.2 M to 0.6 M MgSO 4 , 0.1 M to 0.6 M Tris Base, 0.7 M to 1.4 M Tris HCl, 2 mM to 7 mM EDTA, and 0.5 mM to 2 mM cysteine.
37 . (canceled)
38 . The method of claim 30 , wherein the refolding buffer further comprises 0.25 mM beta-mercapto ethanol.
39 . The method of claim 30 , wherein the protein is diafiltered with 3 diavolumes of diafiltration buffer.
40 . The method of claim 30 , wherein the refolding buffer further comprises 5%-20% sucrose.
41 . (canceled)
42 . The method of claim 30 , wherein the protein is added in 1 to 3 dilutions with 0 to 4 hours between dilutions.
43 . (canceled)
44 . The method of claim 30 , further comprising recovering the protein via hydrophobic interaction chromatography (HIC).
45 . The method of claim 30 , wherein the pH of the mixture of the concentrated protein and the refolding buffer is lowered to about 2.1 to 5.8 prior to HIC.
46 . (canceled)
47 . The method of claim 30 , wherein the solution contains about 20 gm/L of protein.
48 - 52 . (canceled)
53 . The method of claim 3 , wherein the elution buffer comprises 10-14% 2 M ammonium sulfate, 8 mM to 12 mM potassium phosphate, pH 3.0/85-88% 10 mM potassium phosphate, at pH 3.0.
54 . (canceled)
55 . The method of claim 3 , wherein the protein solution is adjusted to a pH of about 2.1 to 5.8 prior to HIC.
56 - 59 . (canceled)