Purity of Viral Vector
Residual Impurities in Viral Vector
The process of producing viral vectors involves a biological system that naturally generates byproducts. If these byproducts or contaminants aren't effectively separated from the vector, it could lead to adverse reactions upon administration. Hence, it's crucial to ensure the purity of the viral vector before its use in both preclinical and clinical trials. These impurities encompass various factors, including:
- Host cell protein (HCP), is a significant impurity in viral vector manufacturing, posing a primary risk of immunogenicity.
- Host cell DNA and plasmid DNA, share similar structural units but possess varying fragment lengths and physical forms. Their presence can result in a diverse range of consequences.
- Nucleases can be introduced in the process of removing plasmid DNA and host DNA.
- Specific process-related residues, such as BSA, PEI, helper virus, and residues from decontaminants.
Impurity Detection Methods in Viral Vector
Creative Biolabs has formulated thorough testing methods, as shown in Tab.1, to detect impurities as a critical quality parameter, encompassing all potential impurities that could arise during viral vector production while adhering to pertinent regulatory quality control standards. The utilization of diverse analytical techniques has facilitated process optimization, thereby guaranteeing the safety and efficacy of the viral vectors.
Tab.1 The impurity test methods for viral vectors.
| Impurity | Method |
|---|---|
| Host cell protein (HCP) | Enzyme-Linked Immunosorbent Assay (ELISA) |
|
Mass Spec (MS): It offers direct insights into HCP characteristics such as isoelectric point (pI), molecular weight (MW), abundance, and identification. |
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SDS-PAGE: It is the most commonly used method. |
|
| Host DNA / Plasmid DNA |
qPCR: By employing specific primers and probes, specific target sequences can be quantified. The concentration of residual DNA can be determined by introducing a standard sample of known concentration to establish a standard curve. Subsequently, the concentration of the original template can be extrapolated based on the position of the sample being tested on the standard curve. |
|
DNA probe hybridization: The exogenous DNA is denatured and adsorbed onto a solid-phase membrane, then hybridized with a labeled DNA probe at a specific temperature. The hybridized DNA forms double-stranded DNA, which is detected using a display system corresponding to a specific marker. The quantity of exogenous DNA in the sample is assessed by comparing it to a positive DNA control of known content and examining the intensity of color development during the reaction. |
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Threshold method: Quantitative detection of single-stranded DNA (ssDNA) involves measuring the total DNA content in the sample using two non-specific DNA sequence-binding proteins: single-stranded DNA (ssDNA) binding protein and an anti-ssDNA monoclonal antibody that binds to denatured DNA. |
|
| Nuclease | ELISA |
| Specific process-related residues | MS |
SERVICES
At Creative Biolabs, we provide a comprehensive solution for impurity detection. Our dependable assay technology ensures precise results, ensuring the delivery of high-quality and pure viral vectors to our clients. If you have any requirements, please don't hesitate to reach out to us, and our seasoned specialists will be delighted to help you.
