Methods and compositions for preparing surfactant protein D (SP-D)
Some embodiments of the methods and compositions provided herein relate to the preparation surfactant protein-D (SP-D). Some embodiments include the expression of human SP-D in certain cell lines, and the purification of human SP-D from such cell lines. Some embodiments include the preparation of certain oligomeric forms of human SP-D.
1. A pharmaceutical solution comprising a population of recombinant human surfactant protein D (SP-D) polypeptides having oligomeric forms, wherein greater than about 40% of the oligomeric forms are dodecamers of the SP-D polypeptides; and a histidine buffer.
2. The pharmaceutical solution of claim 1 , wherein the human SP-D polypeptides comprise the amino acid sequence of positions 22 to 376 of SEQ ID NO:04.
3. The pharmaceutical solution of claim 1 , wherein the oligomeric forms comprise a residue at a polymorphic position, wherein the residue is selected from the group consisting of Met at position 31 of SEQ ID NO:04, Thr at position 180 of SEQ ID NO:04, Ser at position 270 of SEQ ID NO:04, and Ala at position 306 of SEQ ID NO:04.
4. The pharmaceutical solution of claim 1 , wherein greater than about 60% of the oligomeric forms are dodecamers of the SP-D polypeptides.
5. The pharmaceutical solution of claim 1 , wherein greater than about 62% of the oligomeric forms are dodecamers of the SP-D polypeptides.
6. The pharmaceutical solution of claim 1 , wherein a distribution of oligomeric forms of the SP-D polypeptides is measured using an asymmetric flow field-flow fractionation with multi-angle light scattering (AF4-MALS) analysis.
7. The pharmaceutical solution of claim 1 , wherein each SP-D polypeptide comprises a complex-type carbohydrate attached at an N-glycosylation site, wherein the population has a glycosylation pattern comprising the following characteristics:
(i) at least 70% of the complex-type carbohydrates include a core fucose;
(ii) at least 10% of the complex-type carbohydrates include at least one sialic acid residue;
(iii) at least 50% of the complex-type carbohydrates include at least a biantennary carbohydrate structure;
(iv) at least 10% of the complex-type carbohydrates include a bisecting N-acetylglucosamine;
(v) less than 10% of the carbohydrates are high-mannose type structures; and
(vi) a detectable amount of α2,6-coupled sialic acid residues.
8. The pharmaceutical solution of claim 7 , wherein the population has a glycosylation pattern comprising one or more of the following characteristics:
(i) at least 20% of the complex-type carbohydrates include a bisecting N-acetylglucosamine; and
(ii) at least 85% of the complex-type carbohydrates include a core fucose.
9. The pharmaceutical solution of claim 1 , wherein each SP-D polypeptide comprises a complex-type carbohydrate attached at an N-glycosylation site, wherein the population has a glycosylation pattern comprising a characteristic selected from the group consisting of:
(i) at least 70% of the complex-type carbohydrates include a core fucose;
(ii) at least 10% of the complex-type carbohydrates include at least one sialic acid residue;
(iii) at least 50% of the complex-type carbohydrates include at least a biantennary carbohydrate structure;
(iv) at least 10% of the complex-type carbohydrates include a bisecting N-acetylglucosamine;
(v) less than 10% of the carbohydrates are high-mannose type structures; and
(vi) a detectable amount of α2,6-coupled sialic acid residues.
10. The pharmaceutical solution of claim 9 , wherein the glycosylation pattern comprises at least 70% of the complex-type carbohydrates include a core fucose.
11. The pharmaceutical solution of claim 9 , wherein the glycosylation pattern comprises at least 10% of the complex-type carbohydrates include at least one sialic acid residue.
12. The pharmaceutical solution of claim 9 , wherein the glycosylation pattern comprises at least 50% of the complex-type carbohydrates include at least a biantennary carbohydrate structure.
13. The pharmaceutical solution of claim 9 , wherein the glycosylation pattern comprises at least 10% of the complex-type carbohydrates include a bisecting N-acetylglucosamine.
14. The pharmaceutical solution of claim 9 , wherein the glycosylation pattern comprises less than 10% of the carbohydrates are high-mannose type structures.
15. The pharmaceutical solution of claim 9 , wherein the glycosylation pattern comprises a detectable amount of α2,6-coupled sialic acid residues.
16. The pharmaceutical solution of claim 9 , wherein the glycosylation pattern comprises at least 20% of the complex-type carbohydrates include a bisecting N-acetylglucosamine.
17. The pharmaceutical solution of claim 9 , wherein the glycosylation pattern comprises at least 85% of the complex-type carbohydrates include a core fucose.
18. The pharmaceutical solution of claim 1 , wherein the population comprises a greater amount of α2,6-linked N-acetylneuraminic acid carbohydrates compared to α2,3-linked N-acetylneuraminic acid carbohydrates.
19. The pharmaceutical solution of claim 1 , wherein the SP-D polypeptides have an antennarity number within a range from 190 to 215.
20. The pharmaceutical solution of claim 1 , wherein an antennarity number for the SP-D polypeptides and an antennarity number for a naturally occurring human SP-D are within 10% from each other.