Encapsulated cells as an enzyme replacement therapy for metachromatic leukodystrophy

Area of Science:

• Neuroscience
• Genetics
• Biotechnology

Background:

• Metachromatic leukodystrophy (MLD) is a lysosomal storage disorder causing myelin degeneration due to arylsulfatase A (ARSA) deficiency.
• Current treatments are limited, especially for symptomatic patients, with gene therapy approved only for specific pre-symptomatic or early-symptomatic MLD cases.
• Existing research explores intrathecal delivery of recombinant ARSA, but continuous delivery methods are needed.

Purpose of the Study:

• To investigate encapsulated-cell therapy as an innovative approach for delivering recombinant ARSA in MLD.
• To evaluate the efficacy and biocompatibility of a cell-based device for continuous ARSA delivery in MLD models.
• To compare different engineered cell constructs and dosages for optimal therapeutic outcomes in the central nervous system (CNS).

Main Methods:

• Developed and tested a cell-based device for continuous delivery of human ARSA.
• Engineered two distinct cell constructs for efficient CNS targeting and evaluated two doses (cell numbers).
• Implanted devices in MLD mice with established disease and assessed biocompatibility and therapeutic efficacy after 3 months.

Main Results:

• The cell-based device was well tolerated and biocompatible in MLD mice.
• Demonstrated correction of sulfatide storage in the CNS of treated mice.
• Showed significant improvement in neuroinflammation markers within the CNS of all treated animals.

Conclusions:

• Cell-based device therapy is a promising strategy for treating symptomatic MLD patients.
• This approach offers continuous ARSA delivery, potentially overcoming limitations of intermittent treatments.
• Further research is warranted to advance this therapy towards clinical application in MLD.