Larger Bio-actuators: Engineered Tissue Upscaling with Perfusable Design Criteria and Microfluidics

Larger Bio-actuators 

Engineered, centimeter-scale skeletal muscle tissues have the potential to replicate muscle physiology and pathology, providing valuable models for studying development, disease, regeneration, drug response, and movement. Scaling up engineered muscle tissue enhances its force generation capabilities, which is essential for applications in bio-hybrid robotics. Achieving this scale in skeletal muscle tissues requires engineering perfusable channels to support cell survival, along with structural elements that promote mechanical stimulation and alignment into uniaxial myofibers.

Tissue Upscaling: How To?

To overcome size constraints in engineered muscle tissue, we have developed a strategy focused on perfusing the tissue to maintain cell viability and function. This approach aims to increase force output and improve the actuation performance of 3D bio-actuators by scaling up skeletal muscle tissue constructs to achieve full maturation. Using high-resolution biofabrication and microfluidics, we have created intratissue perfusable networks to ensure adequate nutrient and oxygen exchange, allowing us to engineer muscle tissue structures beyond the centimeter scale. Our perfusable muscle constructs feature complex designs that promote tissue maturation and high cell survival throughout. These centimeter-scale muscles also include synthetic components co-printed with the living tissue, forming cohesive interfaces and allowing for passive mechanical tension during tissue remodeling.

Impact

By utilizing extrusion-based, multimaterial bioprinting with optimized bioinks and designs, we can produce biohybrid skeletal muscle tissues with in vitro maturation suitable for biomedical applications. These centimeter-scale constructs not only hold promise for high-performance bio-hybrid robotics but also serve as valuable platforms for studying drug distribution under fluid convection, mimicking the muscle’s microvascular environment.

Authors Involved

This research was conducted by a collaborative team from the Soft Robotics Lab at ETH Zurich, including:

Miriam Filippi

Oncay Yasa

Aiste Balciunaite

Robert K. Katzschmann