Mechanisms of Dystrophin Expressing Chimeric Cell Therapy in Duchenne Muscular Dystrophy

Topic:

Clinical Trials

Poster Number: P164

Author(s):

Maria Siemionow, MD, PhD, DSc, University of Illinois at Chicago, Dystrogen Therapeutics Corporation, Grzegorz Biegański, MD, Poznan University of Medical Sciences, Jacek Wachowiak, MD, PhD, Poznan University of Medical Sciences, Jarosław Czarnota, MD, Hospital MedPolonia, Krzysztof Siemionow, MD, PhD, University of Illinois at Chicago, Dystrogen Therapeutics Corporation, Adam Niezgoda, MD, PhD, Poznan University of Medical Sciences, Anna Ziemiecka, MSc, Dystrogen Therapeutics Corporation, Katarzyna Bożyk, MSc, Dystrogen Therapeutics Corporation, Ahlke Heydemann, PhD, University of Illinois at Chicago

Introduction:
Duchenne Muscular Dystrophy (DMD) is a progressive genetic disorder resulting from dystrophin gene mutations, leading to severe muscle degeneration and premature death. Current treatments for DMD are limited, primarily addressing symptoms rather than halting disease progression. Dystrophin Expressing Chimeric cell therapy, DT-DEC01, has emerged as a potential therapeutic alternative, aiming to regenerate muscle tissue in DMD patients by creating chimeric cells through fusion of donor and patient myoblasts.

Methods:
DEC cells were generated via ex vivo polyethylene glycol (PEG)-mediated fusion of myoblasts from healthy donors and DMD patients. The chimeric nature of DEC cells was confirmed by flow cytometry and short tandem repeat (STR)-PCR analysis. In vitro assays characterized DT-DEC01 by assessing markers like desmin, dystrophin, and myosin heavy chain, alongside mitochondrial transfer and myotube formation assays to support the mechanisms of action involved in therapeutic effect after systemic-intraosseous administration of DT-DEC01 therapy to DMD patients.

Results:
The created DT-DEC01 cells exhibited successful chimerism, expressing dystrophin and myosin heavy chain in previously dystrophin-negative DMD cells. Immunofluorescence confirmed the presence of muscle-specific proteins, and Pappenheim staining validated the regenerative potential through myotube formation in DEC cells, whereas DMD myoblasts before fusion did not demonstrate these myogenic features. Myoblast fusion resulted in the transfer of healthy donor mitochondria and the creation of chimeric mitochondria within DT-DEC01, potentially addressing mitochondrial dysfunction in DMD.

Conclusions:
DT-DEC01 therapy demonstrated promising regenerative capacity and safety for systemic DMD treatment. Confirmation of myogenic potential by myotube formation, presence of dystrophin, mitochondrial transfer and chimeric mitochondria support the unique properties of DT-DEC01 therapy as a universal therapeutic approach for all DMD patients and underscore the importance of the presented treatment mechanisms in Duchenne muscular dystrophy.