The term you’re referring to, “AAV,” stands for Adeno-Associated Virus, a commonly used viral vector in gene therapy. AAV is widely used in biotechnology and medical research due to its ability to deliver genetic material to specific cells with high precision and relatively low immunogenicity. Here’s a deeper look at AAV as a delivery method:
Adeno-Associated Virus (AAV) Delivery Method
- Mechanism:
- AAVs are small, non-enveloped viruses that can infect both dividing and non-dividing cells. They are engineered to carry therapeutic genes into the target cells without integrating into the host genome, which reduces the risk of insertional mutagenesis (i.e., causing unintended changes to the host’s DNA).
- Applications:
- Gene Therapy: AAVs are used to deliver healthy copies of genes to replace defective ones in conditions such as hemophilia, muscular dystrophy, and certain types of inherited blindness (e.g., Leber’s congenital amaurosis).
- Cancer Therapy: AAVs can deliver genes that trigger apoptosis (cell death) in cancer cells or enhance the immune system’s ability to recognize and attack tumors.
- Neurological Disorders: AAVs are being explored to deliver genes to the brain for conditions such as Parkinson’s disease, spinal muscular atrophy (SMA), and Huntington’s disease.
- Advantages:
- Tropism: AAVs can be engineered to target specific cell types by modifying their capsid proteins, giving them a high level of specificity.
- Safety: Since AAVs do not integrate into the host genome, they present a lower risk of causing mutations compared to other viral vectors.
- Long-Term Expression: AAV vectors can provide long-term expression of the delivered gene, especially in non-dividing cells, making them suitable for chronic conditions.
- Limitations:
- Limited Cargo Capacity: AAVs have a relatively small packaging capacity (around 4.7 kb), which limits the size of the therapeutic gene that can be delivered.
- Pre-existing Immunity: Some individuals have pre-existing immunity to certain AAV serotypes, which can reduce the effectiveness of the therapy.
- Example Therapies Using AAV:
- Luxturna: An FDA-approved gene therapy for treating Leber’s congenital amaurosis, a form of inherited blindness, uses an AAV vector to deliver a functional copy of the RPE65 gene.
- Zolgensma: A gene therapy for spinal muscular atrophy (SMA) that uses AAV to deliver a functional copy of the SMN1 gene to motor neurons, providing a one-time treatment for this otherwise fatal condition.
AAV is a versatile and powerful tool in the delivery of therapeutic genes, making it a cornerstone of modern gene therapy and personalized medicine.
Adeno-Associated Virus AVV