Location: Dairy and Functional Foods ResearchTitle: Rapid AAV neutralizing antibody determination with a cell-binding assay
|GUO, PING - Temple University Medical School|
|ZHANG, JUNPING - Temple University Medical School|
|HUANG, JIANHE - Temple University Medical School|
|CHEW, HELEN - Temple University Medical School|
|SANG, NIANLI - Temple University Medical School|
|DIAO, YONG - School Of Biomedical Sciences, Huaqiao University|
|XIAO, WEIDONG - Temple University Medical School|
Submitted to: Molecular Therapy
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/22/2018
Publication Date: 11/29/2018
Citation: Guo, P., Zhang, J., Huang, J., Chew, H., Firrman, J., Sang, N., Diao, Y., Xiao, W. 2018. Rapid AAV neutralizing antibody determination with a cell-binding assay. Molecular Therapy. 13:40-46. https://doi.org/10.1016/j.omtm.2018.11.007.
Interpretive Summary: Gene therapy is a type of treatment for disease that works by giving a human cell a correct version of a dysfunctional gene. The Adeno-Associated Virus (AAV) is a safe virus that can be used to deliver the correct gene for gene therapy treatment. However, the human body can have a natural immune response to AAV because it is a virus. This immune response is in the form of neutralizing antibodies (NAB), which bind to AAV and make it unable to enter human cells. Since the presence of NAB hinders gene therapy, it is important to know how much NAB is present in a person accurately and quickly. Here, a new method to detect NAB has been developed that determines the presence of NAB by looking to see if AAV is able to bind to the human cells. This method can be used in clinics for patients that need gene therapy, and results can be obtained quicker than with traditional methods.
Technical Abstract: Recombinant adeno-associated virus (rAAV) vectors have been successfully developed for both basic research and human gene therapy. However, neutralizing antibodies (NAB) against AAV capsids can abolish their infectivity to the target cells, reducing the transduction efficacy. The absence of AAV NAB has become a prerequisite qualification for patients enrolled in gene therapy trials. Nevertheless, accurate assessment of AAV NAB has remained a challenging task. Here, we developed a rapid assay based on the observations that AAV NAB inhibits rAAV binding to the host cell surface and NAB titers are negatively related to the amount of AAV genomes binding to the target cells. By quantifying the AAV genome on the target cells in the presence of anti-sera, AAV NAB titers can be accurately determined. The titer determined by this assay correlates well with the classical transduction-based assays. A major advantage of this new assay is that it can be carried out using a 30 min binding assay without waiting for lengthy transduction outcomes. This assay is independent of transduction performance of AAV serotypes to the target cells. Therefore, the AAV-cell binding assay for NAB determination offers an alternative method for in vivo NAB quantification.