Application Notes

Bacteriophages are used in a broad range of applications, including phage therapy and phage display. With the growing problem of antibiotic resistance leading to untreatable bacterial infections, they are becoming very interesting as antimicrobial agents, not only in medicine, but also in veterinary medicine, food industry and agriculture. Phages intended for use as antimicrobial agents, especially those for human use, need to be purified of contaminants.

Here we present efficient single step purification method for a Staphylococcus aureus phage VDX-10 from bacterial lysate on a CIM® QA Disk Monolithic Column (Figure 1). The described method can be used also on a larger scale using a CIM® QA-8 mL Tube Monolithic Column (Figure 2).

Adenoviruses are among the most commonly used vectors for the delivery of genetic material into human cells and as such there is demand for high-titre manufacturing processes. The key to the successful development of such processes are analytical methods that can be applied to the final purified samples and throughout the production process. Many conventional methods for quantitative analysis of adenoviruses are labour and time-intensive. For example, a plaque assay can take up to 7 days to perform, is prone to error and will only report the number of infectious and not total viral particles. The resolving power of the high-performance liquid chromatography (HPLC), on the other hand, permits separation of intact virus particles from other cellular contaminants or virus particle fragments.

Anion-exchange chromatography has already been applied to analyse various adenovirus preparations. The results from the anion-exchange HPLC methods can be obtained much faster, within minutes, thus allowing for a faster evaluation of different process steps. A method was designed and developed to quantify adenoviral particles using a strong anion-exchange CIMac™ Analytical column. Regeneration conditions were incorporated to extend the functional life of the column.

Bacteriophages, viruses that infect bacteria, are being used as antibacterial agents, in phage display screening, as gene therapy delivery systems, and for bacteria typing. To use phages in these applications, they must be free of all impurities. A purification and concentration process was recently developed using an ion exchange monolithic column [1]. One of the key challenges faced in phage purification is the monitoring of genomic DNA (gDNA) released to the growth medium which can interfere with the various applications of phages. CIMac™ DEAE Analytical Columns can be used to monitor the fermentation process, evaluate the amount of degraded gDNA to determine the optimal fermentation endpoint and then to efficiently purify the phage particles.

Adenovirus vectors have proven as useful tool for gene therapy, vaccine therapy and basic biology studies. The increasing importance of the recombinant adenoviruses pushes the limits of research in the field of adenovirus purification methods. There is a global focus on large scale production of adenovirus vectors, providing high titres combined with fast, effective and reliable purification methods.

Because of the physico-chemical properties adenovirus vectors possess, they can effectively be purified using ion-exchange chromatography. Here we present a simple and rapid method for adenovirus vectors purification using ion-exchange CIM ®QA chromatographic supports (Figure 1). CIM® monolithic supports are a new generation of chromatographic supports able to meet the GMP and GLP requirements in the field of virus purification.

As the demand for plasmid DNA (pDNA) based gene therapy and vaccines increases, large scale, cost effective, and reproducible pDNA production will be required. The key to success is a real time in-process control method that ensures a high percentage of supercoiled pDNA in the final product. CIMac™ pDNA Analytical Column allows the monitoring of degradation products (open circular and linear pDNA), the removal of impurities (RNA), and ensures that each production step is yielding the amount of supercoiled pDNA anticipated.

Diluted samples of live attenuated measles and mumps virus were each loaded on CIM® DEAE Disk. Concentrated eluates of viral RNA were subjected to molecular detection by PCR. It was demonstrated that enrichment of viral RNA on a CIM® DEAE Disk prior PCR is feasible and successful.