Quality assessment of supercoiled minicircle DNA by cadaverine-modified analytical chromatographic monolith

Cryogels and Monoliths: Promising Tools for Chromatographic Purification of Nucleic Acids

The increasing demand for highly pure biopharmaceuticals has put significant pressure on the biotechnological industry to innovate in production and purification processes. Nucleic acid purification, crucial for gene therapy and vaccine production, presents challenges due to the unique physical and chemical properties of these molecules. Meeting regulatory standards necessitates large quantities of biotherapeutic agents of high purity. While conventional chromatography offers versatility and efficiency, it suffers from drawbacks like low flow rates and binding capacity, as well as high mass transfer resistance. Recent advancements in continuous beds, including monoliths and cryogel-based systems, have emerged as promising solutions to overcome these limitations. This review explores and evaluates the latest progress in chromatography utilizing monolithic and cryogenic supports for nucleic acid purification.

Minicircle DNA Vaccine Purification and E7 Antigen Expression Assessment

Human papillomavirus (HPV ) has been extensively associated with the development of cervical cancer due to the expression of oncoproteins like E7. This protein can interfere with pRB tumor suppressor activity, enabling the uncontrolled proliferation of abnormal cells. DNA vaccines are known as the third-generation vaccines, providing the ability of targeting viral infections such as HPV in a preventive and therapeutic way. Although current strategies make use of plasmid DNA (pDNA) as the vector of choice to be used as a DNA vaccine, minicircle DNA (mcDNA) has been proving its added value as a non-viral DNA vector by demonstrating higher expression efficiency and increased biosafety than the pDNA. However, due to its innovative profile, few methodologies have been explored and implemented for the manufacture of this molecule. This chapter describes the detailed procedures for the production, extraction, and purification of supercoiled E7-mcDNA vaccine, by using size-exclusion chromatography to obtain mcDNA with a purity degree which meets the regulatory agency criteria. Then, the assessment of E7 antigen expression through immunocytochemistry is also described.

Minicircle DNA: The Future for DNA-Based Vectors?

Minicircle DNA (mcDNA) is a smaller and safer version of non-viral DNA vectors that results from a cutting-edge in vivo recombination process to excise prokaryotic sequences from plasmid DNA (pDNA). Considering the molecule's potential and increasing interest as a non-viral DNA-based therapeutic, biomanufacturing methodologies need to be improved, especially in downstream processing.