Rapid AAV-Neutralizing Antibody Determination with a Cell-Binding Assay.

Area of Science:

• Molecular Biology
• Immunology
• Gene Therapy

Background:

• Recombinant adeno-associated virus (rAAV) is a key vector in gene therapy.
• Neutralizing antibodies (NAbs) against AAV capsids impede transduction efficacy.
• Accurate assessment of AAV NAbs is crucial for patient selection in gene therapy trials.

Purpose of the Study:

• To develop a rapid and accurate assay for determining AAV NAb titers.
• To provide an alternative to lengthy transduction-based NAb assays.

Main Methods:

• Developed a cell-binding assay measuring rAAV genome binding to target cells in the presence of patient sera.
• Quantified bound AAV genomes to determine NAb titers.
• Correlated results with established transduction-based assays.

Main Results:

• The developed assay accurately determines AAV NAb titers.
• Assay results show strong correlation with classical transduction-based assays.
• This method provides results within a 30-minute binding assay, significantly faster than traditional methods.

Conclusions:

• The AAV cell-binding assay offers a rapid and reliable alternative for NAb determination.
• This assay is independent of AAV serotype and target cell transduction efficiency.
• It provides a valuable tool for assessing patient eligibility for AAV-based gene therapies.