Heparin Affinity Chromatography
Affinity chromatography is attractive because of its high selectivity, high resolution and high viral binding ability, which makes it commonly used as a method to remove process-related impurities in the manufacture of biological agents. Heparin is a highly sulfated glycosaminoglycan, which is widely used as a general affinity ligand. It also showed a good effect on the purification of adeno-associated virus (AAV). Based on our expertise in gene therapy, Creative Biolabs provides high-quality heparin affinity chromatography purification services for AAV vectors.
Heparin Affinity Chromatography for AAV Vector Purification
Viral vectors are needed to produce gene therapy and gene-modified cells for various cell therapies. AAV, as one of cell therapy vectors, needs to be purified to improve its titer and efficacy. In recent years, vector purification has developed towards chromatography. The use of affinity chromatography eliminates some of the burdens of downstream purification steps of affinity steps, enabling the focus to point to specific attributes, such as the enrichment of complete capsid, rather than the removal of crude impurities in the product stream. Interest in chromatographic solutions has led to the development of several new affinity ligands for viral vector purification. Affinity columns with specific antigens for each AAV serotype have been used to purify gene therapy products based on AAV. It has been pointed out that a new affinity purification method using heparin sulfate proteoglycan on the cell surface and iodixanol as a non-ionic gradient medium can improve the viral infectivity, efficient purification of AAV vectors.
Heparin Affinity Chromatography Services
Affinity chromatography can separate virus particles from protein and DNA contaminants based on the reversible interaction between virus capsid, specific biological ligands or receptors and chromatographic matrix. This technology is an ideal capture or intermediate step in purification protocol that can be used at any time for the appropriate separation of specific ligand or receptor. In the purification of AAV vectors, the discovery of heparin sulfate proteoglycan mediating the entry of AAV-2 cells promotes the development of several purification schemes of AAV-2 based heparin affinity. Creative Biolabs has achieved some success in purifying AAV virus by heparin affinity chromatography. AAV-2 was purified from the heparin column by high-performance liquid chromatography (HPLC) and the recovery of AAV-2 in crude pyrolysis solution was over 70%. Compared with the viruses purified by cesium chloride density gradient, the AAV-2 vector purified on the heparin column has higher bioavailability and higher infection rates.
Figure 1. Principle of affinity chromatography. (Zhao, 2019)
Features of Our Services
Chromatographic purification of viruses improves the selection of downstream processes, making gene therapy possible. The highly sulfated heparin gives the molecule strong acidity, so it can bind to many substances through ion interaction. Heparin affinity chromatography has been used to purify AAV and other viruses and has been reported to be able to handle large volumes. These new developments, especially in chromatographic methods, have improved the selection of downstream processes, making gene therapy possible. In addition to heparin, we can also provide suitable selective ligands on beaded and porous matrices for binding to target compounds and then recover them under mild conditions.
If you are interested in our chromatographic purification service, please feel free to contact us.
Reference
- Zhao, M.; et al. (2019). Affinity chromatography for vaccines manufacturing: Finally ready for prime time. Vaccine. 37(36): 5491-5503.
