Chimeric AAV Capsid Proteins for Enhanced Transduction

Solution Overview

Problem

Current AAV-2 vectors face limitations such as inefficient transduction of clinically relevant cell types and tissues, high immunogenicity due to pre-existing antibodies in humans, and restricted biodistribution, which hinders their effectiveness in gene therapy applications.

Innovation Solution

Development of recombinant AAV vectors with capsid proteins comprising regions from multiple AAV serotypes, such as AAV-2, AAV-8, and AAV-9, to create a novel capsid protein (AAV-DJ) with enhanced transduction efficiency and immune evasion capabilities, generated through a library of shuffled capsid genes and sequences with high sequence identity, allowing for improved tissue tropism and resistance to neutralization.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If AAV-2 vectors are used for gene transfer, then stable long-term transgene expression is achieved, but transduction efficiency in clinically relevant cell types and tissues is poor

Engineering Contradiction:

Improvetransduction efficiencyVSAvoidstable long-term transgene expression

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent combines capsid protein sequences from multiple AAV serotypes (AAV-2, AAV-8, AAV-9) to create chimeric capsid proteins that integrate the stable transgene expression capability of AAV-2 with the enhanced transduction efficiency of AAV-8 and AAV-9 variants

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The invention creates composite capsid structures by fusing homologous regions from different AAV serotypes, resulting in hybrid capsid proteins that exhibit properties of all parent serotypes including improved transduction efficiency while maintaining stable expression

Inventive Principle:

Principle #40Composite materials

2Ease of manufacture

If AAV-2 vectors are used, then the technology to produce and purify vectors is well-established, but neutralization by pre-existing human antibodies occurs in up to 67% of seropositive individuals

Engineering Contradiction:

Improveproduction and purification technologyVSAvoidneutralization by anti-AAV-2 antibodies

Core Design Contradiction:

Ease of manufactureVSObject-affected harmful factors

Solution Approach 1:

The patent modifies specific regions of the capsid protein sequence while preserving other regions, creating localized changes that reduce antibody recognition in key epitopic regions while maintaining overall capsid structure and production compatibility

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The invention alters the amino acid sequence parameters of the capsid protein by incorporating sequences from AAV-8 and AAV-9, changing the immunogenic properties of the vector while maintaining manufacturability through homologous recombination

Inventive Principle:

Principle #35Parameter changes

3Adaptability or versatility

If AAV-2 vectors are administered systemically, then gene transfer to multiple tissues is possible, but cell-mediated immune responses are triggered in patients

Engineering Contradiction:

Improvetissue distributionVSAvoidcell-mediated immune response

Core Design Contradiction:

Adaptability or versatilityVSObject-generated harmful factors

Solution Approach 1:

The patent modifies specific regions of the capsid protein sequence while preserving other regions, creating localized changes that reduce antibody recognition in key epitopic regions while maintaining overall capsid structure and production compatibility

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The invention alters the amino acid sequence parameters of the capsid protein by incorporating sequences from AAV-8 and AAV-9, changing the immunogenic properties of the vector while maintaining manufacturability through homologous recombination

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentEP2007795B1AAV capsid proteins

Publication Date: 2016.11.16 THE BOARD OF TRUSTEES OF THE LELAND STANFORD JUNIOR UNIV

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Figure 2C~3

AI summary

Recombinant adeno-associated viral (AAV) capsid proteins are provided. Methods for generating the recombinant adeno-associated viral capsid proteins and a library from which the capsids are selected are also provided.