EAGER: 3D Printing of Aligned Muscle Fibers for Thick Structured Meat Production

The continued growth of human populations with declined resources has imposed a significant challenge to affordable and sustainable foods and nutrition. One resource-efficient solution is cultured meat, which is genuine animal meat produced by cultivating animal cells directly using a bioreactor. Though scaffold-based technologies have demonstrated the feasibility of making minced or unstructured meat products, such technologies are limited and cannot produce thick structured meat.

This EArly-concept Grant for Exploratory Research (EAGER) supports fundamental research that aims to establish a scaffold-free 3D embedded bioprinting technology to enable the production of cultured meat with centimeter thick and structured features. The study will explore the alignment and fusion of myoblasts during embedded meat printing in a gelatin composite-based cellular matrix bath.

The results will catalyze future scale-up production of thick structured cuts of cultured meat and promote cellular agriculture as the future of complementary food production for the benefits of sustainability, public health, and animal welfare. The project will also stimulate science-based bioprinting research to advance cultured-meat manufacture and broaden the participation of underrepresented students in crosscutting STEM fields via the bioprinting study.

The objective of this research is to understand the effects of extrusion-induced shear force and post-printing tension on the formation of aligned muscle fibers from myoblasts during embedded printing of thick multicellular structured meat-like tissues. Specifically, myoblasts will be printed in an embedded manner, aligned, and stretched for myoblast fusion to be myotubes and further matured as myofibers in the gelatin composite-based yield-stress matrix bath.

The printed sacrificial bioink will then be removed to form perfusable channels. While embedded 3D printing of myoblasts and adipocyte progenitor cells will enable printed tissues to be structured, the perfusable channels and capillaries self-assembled by endothelial and adipose-derived stem cells will enable the printed tissues to grow thick. Theoretically, the effect of shear force on the myoblast alignment during printing will be computationally modeled using the Eulerian formulation and myoblasts will be macroscopically treated as a linear elastic solid in the myoblast bioink.

The modeling results will be validated with the orientation of the printed myoblasts. Next, the cyclic tension-induced effect on myoblast fusion will be investigated during the culturing of the printed meat-like tissues in a customized bioreactor, and the printed tissues will be perfused via the channels. The resulting meat-like tissues will be characterized in terms of vascularization, myoblast differentiation as well as myotube and myofiber formation.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.