Chiara Villa1, Andrea Farini2, Marzia Belicchi1, Yvan Torrente 1,2.
1Stem Cell Laboratory, Department of Pathophysiology and Transplantation, Dino Ferrari Centre, Università degli Studi di Milano, Milan, Italy
2Neurology Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan, Italy
Introduction
Duchenne muscular dystrophy (DMD) is characterized by progressive muscle degeneration, yet systemic immunological consequences remain poorly understood. Recent fatalities following AAV-mediated gene therapy highlight critical gaps in baseline immune dysfunction knowledge. This study aimed to comprehensively characterize systemic immune profiles in glucocorticoid-free DMD patients using multi-omic approaches.
Methods
We performed single-cell transcriptomic and epigenomic profiling coupled with systemic cytokine analysis in glucocorticoid-free DMD patients. Immune cell populations were characterized across bone marrow, dystrophic muscle, and peripheral blood compartments. Cell-cell communication networks were analyzed, and findings were validated through meta-analysis across independent cohorts.
Results
DMD exhibited distinct immune microenvironments: bone marrow harbored transcriptionally primed yet phenotypically naïve lymphocytes with stress-responsive signatures (ATF3, FOSB) and metabolic reprogramming. Dystrophic muscle showed chronic T cell exhaustion with epigenetic imprinting. Paradoxically, circulating CD8+ memory T cells maintained TCF1+TIGIT− stem-like features despite tissue exhaustion. Systemic profiling revealed elevated pro-inflammatory mediators (IL-6, TNF receptors, interferons) with impaired chemokine networks. Bone marrow networks centered on monocyte-mediated T cell priming, while muscle networks involved FAP-myofiber-macrophage triads driving remodeling.
Conclusion
Pre-existing immune priming in DMD—characterized by stress-responsive transcription, enhanced OXPHOS metabolism, and preserved T cell stemness—may predispose patients to exaggerated therapeutic responses, providing essential groundwork for predicting complications and designing immunomodulatory strategies.
Disclosures
None.