Integrated patient induced pluripotent stem cell models and Gaa-/- mice reveal central nervous system neural pathology in infantile-onset Pompe disease

Abstract

BACKGROUND

Pompe disease, or glycogen storage disease type II, is an autosomal recessive disorder caused by pathogenic variants in the acid α-glucosidase (GAA) gene. Although enzyme replacement therapy has improved survival in infantile-onset Pompe disease (IOPD), central nervous system (CNS) involvement has become increasingly evident because recombinant human GAA cannot cross the blood-brain barrier. The lack of reliable human models that faithfully recapitulate neural pathology has hindered mechanistic studies and the development of targeted therapies.

AIM

To establish an integrated disease-modeling platform by combining patient-derived induced pluripotent stem cell (iPSC) neural lineages with Gaa^-/- mice to reveal the cell-type-specific and progressive CNS pathology characteristic of IOPD.

METHODS

We generated iPSCs from peripheral blood mononuclear cells obtained from an enzyme replacement therapy-naïve IOPD patient and differentiated them into major CNS-relevant neural lineages, including cortical neurons, astrocytes, oligodendrocytes, and spinal motor neurons. These patient-derived neural cells were systematically assessed for lysosomal pathology and compared with the corresponding CNS phenotypes in Gaa^-/- mice. Lysosomal enlargement was quantified at the single-cell level in human neural cultures, whereas fluorescence-based intensity and area-fraction analyses were performed on mouse cerebral cortex and spinal cord tissues to evaluate in vivo lysosomal and glycogen-storage pathology.

RESULTS

Patient-derived iPSC neural cells exhibited marked lysosomal enlargement in cortical neurons, astrocytes, oligodendrocytes, and motor neurons, closely mirroring the cell-type-specific pathology observed in Gaa^-/- mice. In vivo, PAS staining revealed widespread glycogen accumulation in the cerebral cortex, hippocampus, and spinal cord, accompanied by pronounced lysosomal expansion across multiple neural populations. Gaa^-/- mice also showed progressive CNS involvement, with robust astrogliosis and substantial neuronal loss by six months of age. Consistently, long-term cultures of patient-derived neurons showed increased cleaved caspase-3-positive apoptosis.

CONCLUSION

Our integrated iPSC and mouse modeling approach recapitulates the essential CNS pathological features of IOPD, providing a relevant platform for mechanistic studies. This system may help guide future efforts to develop CNS-directed therapeutic strategies.

Keywords: Pompe disease; Lysosomal storage disease; Central nervous system; Blood-brain barrier; Induced pluripotent stem cells

Core Tip: This study integrates patient-derived induced pluripotent stem cell neural lineages and Gaa^-/- mice to model central nervous system pathology in infantile-onset Pompe disease. Patient-specific cortical neurons, astrocytes, oligodendrocytes, and motor neurons recapitulate key lysosomal pathology seen in vivo. Gaa^-/- mice exhibit progressive glycogen accumulation, astrogliosis, and neuronal loss. This dual-platform approach faithfully reproduces infantile-onset Pompe disease neural features, providing a valuable system for mechanistic research and testing central nervous system-directed therapies.