Evading the AAV Immune Response in Mucopolysaccharidoses

Area of Science:

• Immunology
• Gene Therapy
• Biotechnology

Background:

• Humoral immune responses against adeno-associated virus (AAV) capsids and transgene products impede effective gene therapy for mucopolysaccharidoses (MPS).
• Pre-existing and treatment-induced antibodies against AAV limit patient eligibility and re-treatment options in clinical trials.
• The efficacy of AAV gene therapy for MPS is significantly reduced by the generation of anti-AAV antibodies, impacting enzyme replacement and disease management.

Purpose of the Study:

• To review the mechanisms underlying the anti-AAV humoral immune response in the context of MPS gene therapy.
• To evaluate the current strategies for overcoming immune responses to AAV vectors.
• To provide evidence-based recommendations for future AAV gene therapy approaches in MPS.

Main Methods:

• Review of existing literature on anti-AAV immune responses.
• Analysis of current and emerging strategies for immune evasion in AAV gene therapy.
• Evaluation of the strengths and limitations of different evasion techniques.

Main Results:

• Antibodies targeting AAV capsids and transgene products reduce essential enzyme production for MPS treatment.
• Patient populations eligible for AAV gene therapy are restricted by age, serotype, and racial background due to pre-existing antibodies.
• Various immune evasion strategies, including novel serotypes, plasmapheresis, immunosuppression, and vector modifications, are under development.

Conclusions:

• Understanding the anti-AAV immune response is critical for successful AAV gene therapy in MPS.
• Current immune evasion strategies offer potential solutions but require further validation.
• Optimizing AAV gene therapy for MPS necessitates a comprehensive approach to mitigate immune barriers and enhance therapeutic outcomes.