Opportunity
Mitochondrial dysfunction is a critical factor in numerous diseases, including mitochondrial DNA (mtDNA)-related disorders, muscle atrophy, and other degenerative conditions. The severity of these diseases is often determined by heteroplasmy—the ratio of mutant to wild-type mtDNA. Current therapies, such as myoblast transplantation, face significant challenges, including immune rejection (e.g., CD8+ T lymphocyte attacks) and low efficacy in restoring cellular function. Existing mitochondrial transfer methods, such as co-culture and microinjection, suffer from major limitations. Co-culture techniques, while minimally invasive, exhibit low transfer efficiency (≤28%) and high heterogeneity (1–60 mitochondria per cell), making it difficult to achieve consistent therapeutic outcomes. Microinjection, though precise, is low-throughput and risks damaging recipient cells. There is an urgent need for a high-throughput, quantitative, and minimally invasive method to transfer mitochondria into recipient cells for precise medicine applications, particularly in cell therapy for mtDNA-related diseases.
Technology
The patent introduces a droplet microfluidics-based system for high-efficiency, quantitative mitochondrial transfer. The system comprises:
1. Droplet Generation Module: Encapsulates isolated mitochondria and single recipient cells (e.g., C2C12 myoblasts) into uniform droplets (∼40 µm diameter) using a flow-focusing structure. A wave-like structure improves single-cell encapsulation efficiency to >47% while suppressing multi-cell encapsulation to <6%.>
2. Droplet Observation Module: Enables real-time monitoring of mitochondrial transfer via microscopy.
3. Droplet Collection Module: Harvests droplets for downstream applications.
The innovation lies in the closed microenvironment of droplets, which confines mitochondria and cells, enhancing contact probability and transfer efficiency (≥75%). By adjusting mitochondrial suspension concentration, the system precisely controls the number of mitochondria transferred per cell (e.g., 8, 14, or 31 mitochondria per cell). This method achieves high throughput (2×10⁵ cells processed in 30 minutes) without compromising cell viability (≥95%).
Advantages
- Precision: Quantitative control of mitochondrial transfer at the single-cell level.
- High Efficiency: Transfer efficiency of ≥75%, far surpassing co-culture methods.
- High Throughput: Processes thousands of droplets per second, enabling scalable cell therapy production.
- Minimal Cell Damage: Gentle encapsulation avoids membrane disruption (unlike microinjection).
- Consistency: Uniform droplet size (40 µm) ensures reproducible results.
- Versatility: Applicable to various cell types and mitochondrial therapies.
Applications
- Cell Therapy: Treatment of mtDNA-related diseases (e.g., mitochondrial myopathies, Leigh syndrome).
- Muscle Regeneration: Enhancing myogenic differentiation in skeletal muscle disorders.
- Stem Cell Research: Improving mitochondrial function in stem cell therapies.
- Drug Screening: High-throughput testing of mitochondrial-targeted drugs.
- Aging Research: Studying mitochondrial dysfunction in age-related degeneration.
