Hokkaido University Scientists Develop e-MITO: A Surface-Engineered Mitochondrial Delivery System for Organelle-Based Therapeutics
核心洞察
Researchers at Hokkaido University developed e-MITO, a surface engineering approach that coats isolated mitochondria with PEG and cell-penetrating peptides to enhance stability and cellular uptake.
In laboratory experiments, CPP–PEG-engineered mitochondria were taken up more efficiently by cells than unmodified mitochondria and led to increased mitochondrial respiratory activity in recipient cells.
The modular design could enable mitochondria to be targeted to specific diseases or tissues, representing an early step toward using organelles as therapeutic tools.
Researchers at Hokkaido University in Sapporo, Japan, have developed a new surface engineering method that significantly improves the delivery of functional mitochondria into living cells, addressing longstanding barriers in the emerging field of mitochondrial transplantation. The technology, named e-MITO (enhanced artificially designed mitochondria), was described in a paper recently published in Advanced Materials Interfaces.
Mitochondria, the bean-shaped organelles responsible for cellular energy production, are implicated in a range of severe diseases affecting the brain, heart, and other vital organs when they malfunction. While most current therapeutic strategies focus on supplementing missing components such as proteins or antioxidants, mitochondrial transplantation — the direct delivery of healthy mitochondria into target cells to modulate energy metabolism — has drawn increasing interest as a more fundamental intervention. However, conventional mitochondrial preparations are fragile, rapidly lose function during handling and storage, and are poorly taken up by cells.
A Dual-Layer Surface Engineering Strategy
To overcome these limitations, the Hokkaido University team employed a two-component surface engineering approach. Isolated mitochondria are first coated with a protective layer of polyethylene glycol (PEG), a pharmaceutical-grade polymer that acts as a shield to preserve mitochondrial structure and serves as a platform for attaching additional functional molecules. The researchers then conjugated cell-penetrating peptides (CPP) to the outer end of this PEG layer, positioning the peptides away from the mitochondrial membrane. This design simultaneously enhanced mitochondrial uptake by target cells and preserved the integrity of the mitochondria's outer membrane under experimental conditions.
In laboratory experiments, the CPP–PEG-engineered mitochondrial preparations demonstrated superior cellular uptake compared to unmodified mitochondria. Critically, recipient cells containing the modified mitochondria subsequently showed increased mitochondrial respiratory activity, confirming that the delivered organelles retained their energy-producing function.
Toward Organelle-Based Therapeutics
Professor Yuma Yamada, who led the study, emphasized the broader implications of the modular platform. "The modular nature of this approach could be a real advantage that could enable us to design mitochondria targeted to treat a specific disease or tissue," Yamada said. "This work represents an early step toward a new field in which organelles themselves serve as therapeutic tools, much like genes, proteins, and cells. Organelle-derived materials could offer new opportunities to control cellular functions in the future."
The research was supported in part by the Japan Science and Technology Agency (JST) through the Fusion Oriented Research for Disruptive Science and Technology (FOREST) Program (JPMJFR203X) and by the Japan Agency for Medical Research and Development (AMED; JP25ym012684 and JP223fa627005).