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AAV Neutralizing Antibody Assay

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In recent years, adeno-associated virus (AAV) has emerged as a popular gene therapy vector due to its safety profile and efficiency. However, pre-existing AAV-specific antibodies (Abs) can significantly hinder gene therapy efficacy in patients. Moreover, AAV antibody titers can vary over time within individuals, and therapy-induced Abs may prevent the re-administration of the same AAV vector for future treatments. Therefore, it is essential to assess the presence and level of neutralizing antibodies (NAbs) against AAV using an AAV neutralizing antibody (NAb) assay to determine a patient’s suitability for AAV gene therapy.


Figure 1.  Mechanisms for the inhibition of vector transduction and transgene expression by neutralizing anti-AAV antibodies

Applications

● Before clinical treatment: NAb assay can inform the selection of AAV serotypes, administration routes, and drug doses for personalized AAV gene therapy regimens.

● During clinical treatment: By monitoring NAb trends, AAV NAb assay can evaluate whether gene therapy medications have achieved effective therapeutic dosage levels, assess drug efficacy, and determine the duration of therapeutic effects.

Service Offerings

1.AAV NAb Assay (Transfection Inhibition, TI)

Using our various AAV serotypes, we simulate the biological process of antibodies blocking AAV entry into cells to detect the neutralizing activity of serum/antibodies against AAV and calculate the NAb titers.


●Cell selection: HEK 293

●Assay design:

AAVs are pre-incubated with serially diluted serum/antibody samples before being used to infect cells. After 48 hours, fluorescence intensity is measured across all dilutions using a multi-mode microplate reader. By comparing the infection efficiency in the presence and absence of serum/antibodies, we can determine the IC50 value and evaluate the neutralizing capacity of the tested antibodies or serum.

●Samples:

a. Sample types: serum, body fluid, vitreous humor, etc., transported on dry ice;

b. Sample volume: > 30 μl (customizable for special needs);

c. Sample requirements: sterile, negative for Hepatitis B, Hepatitis C, HIV, Syphilis, EB, CMV, etc.

d. Species: Human, monkey, mouse, etc.


Why choose us

We utilize the Luciferase reporter gene system to mimic the natural process of antibodies blocking AAV entry into cells, providing a more intuitive and systematic representation of the neutralization process. This assay is characterized by high sensitivity, high specificity, high throughput and high accuracy.


Data Presentation