Methods for producing preparations of recombinant AAV virions substantially free of empty capsids
Methods for separating AAV empty capsids from mixtures of AAV vector particles and AAV empty capsids are described. The methods use column chromatography techniques and provide for commercially viable levels of recombinant AAV virions.
1. A method for purifying AAV vector particles from an AAV preparation comprising AAV vector particles and AAV empty capsids, to provide an AAV product substantially free of AAV empty capsids, said method comprising:
(a) providing a host cell comprising AAV vector particles;
(b) lysing said host cell to obtain a crude cell lysate comprising AAV vector particles and AAV empty capsids;
(c) applying said crude cell lysate to a cation exchange chromatography column under conditions whereby said AAV vector particles and said AAV empty capsids bind the column;
(d) eluting said AAV vector particles and said AAV empty capsids under non-separating conditions to provide an AAV preparation comprising AAV vector particles and AAV empty capsids;
(e) applying the AAV preparation from (d) to an anion exchange chromatography column under conditions whereby said AAV vector particles and said AAV empty capsids bind the column;
(f) adding a low salt buffer to the column from (e) under conditions whereby AAV empty capsids are eluted and AAV vector particles remain bound to the column;
(g) adding a high salt buffer to the column from (f) under conditions whereby AAV vector particles are eluted;
(h) collecting eluted fractions from (g) that comprise AAV vector particles to provide an AAV product substantially free of AAV empty capsids;
(i) applying the AAV preparation from (h) to a second cation exchange chromatography column under conditions whereby said AAV vector particles and said AAV empty capsids bind the column;
(j) adding a low salt buffer to the column from (i) under conditions whereby AAV vector particles are eluted and AAV empty capsids remain bound to the column; and
(k) collecting eluted fractions from (j) that comprise AAV vector particles to provide an AAV product substantially free of AAV empty capsids;
(l) applying the AAV preparation from (k) to a second anion exchange chromatography column under conditions whereby said AAV vector particles and said AAV empty capsids, if present, bind the column;
(m) adding a low salt buffer to the column from (l) under conditions whereby AAV empty capsids are eluted and AAV vector particles remain bound to the column;
(n) adding a high salt buffer to the column from (m) under conditions whereby AAV vector particles are eluted;
(o) collecting eluted fractions from (n) that comprise AAV vector particles to provide an AAV product substantially free of AAV empty capsids.
2. The method of claim 1 , wherein AAV vector particles are present in said AAV product in an amount of at least 75%.
3. The method of claim 1 , wherein AAV vector particles are present in said AAV product in an amount of at least 85%.
4. The method of claim 1 , wherein AAV vector particles are present in said AAV product in an amount of at least 90%.
5. The method of claim 1 , wherein said AAV vector particles are derived from AAV-2.
6. The method of claim 1 , wherein said AAV vector particles are derived from AAV-5.
7. The method of claim 1 , wherein said first cation exchange column comprises a carboxymethylated or sulfonated matrix.
8. The method of claim 7 , wherein said matrix comprises the functional ligand R—SO 3 —.
9. The method of claim 1 , wherein said second cation exchange column comprises a carboxymethylated or sulfonated matrix.
10. The method of claim 9 , wherein said matrix comprises the functional ligand R—SO 3 —.