AAV Engineering for Improving Tropism to the Central Nervous System.

Area of Science:

• * Gene Therapy Vector Development
• * Viral Vector Engineering
• * Neuroscience and Drug Delivery

Background:

• * Adeno-associated virus (AAV) is a non-pathogenic viral vector widely used in gene therapy.
• * Current AAV applications show promise for CNS, ocular, muscular, and liver diseases.
• * Challenges include low delivery efficiency, especially to the central nervous system (CNS) due to the blood-brain barrier (BBB).

Purpose of the Study:

• * To review key studies on engineered AAV capsids for enhanced CNS delivery.
• * To discuss methodological improvements in AAV engineering.
• * To highlight the need for next-generation capsids with improved properties like BBB penetrance and reduced immunogenicity.

Main Methods:

• * Review of studies employing directed evolution, rational design, and in silico design for AAV capsid engineering.
• * Analysis of methods used to discover novel CNS-targeting AAV capsids.
• * Discussion of strategies for improving AAV properties such as delivery efficiency and immunogenicity.

Main Results:

• * Identification of engineered CNS capsids (e.g., PhP.B, B10, PAL1A/B/C) through various engineering approaches.
• * Demonstration of methodological advancements in creating improved AAV vectors.
• * Highlighting the potential of engineered capsids to overcome BBB limitations.

Conclusions:

• * AAV engineering is crucial for advancing gene therapy, especially for CNS disorders.
• * Further research is needed to address cross-species translatability and cell specificity.
• * Modular engineering approaches may enable simultaneous improvement of multiple AAV capsid properties.