Stretchable zein-coated alginate fiber for aligning muscle cells to artificially produce cultivated meat.

Numerous studies have explored the cultivation of muscle cells using non-animal materials for cultivated meat production. Achieving muscle cell proliferation and alignment using 3D scaffolds made from plant-based materials remains challenging. This study introduces a technique to culture and align muscle cells using only plant-based materials, avoiding toxic chemical modifications. Zein-alginate fibers (ZA fibers) were fabricated by coating zein protein onto alginate fibers (A fibers). Zein's excellent cell compatibility and biodegradability enable high cell adhesion and proliferation rates, and the good ductility of the ZA fibers enable a high strain rate (>75%). We demonstrate mature and aligned myotube formation in ZA fibers, providing a simple way to align muscle cells using plant-based materials. Additionally, cultivated meat was constructed by assembling muscle, fat, and vessel fibers. This method holds promise for the future mass production of cultivated meat.

Efficient Myogenic/Adipogenic Transdifferentiation of Bovine Fibroblasts in a 3D Bioprinting System for Steak-Type Cultured Meat Production.

The interest in cultured meat is increasing because of the problems with conventional livestock industry. Recently, many studies related to cultured meat have been conducted, but producing large-sized cultured meat remains a challenge. It is aimed to introduce 3D bioprinting for producing large cell aggregates for cultured meat production. A hydrogel scaffold is produced at the centimeter scale using a bioink consisting of photocrosslinkable materials for digital light processing-based (DLP) printing, which has high printing accuracy and can produce geometrically complex structures. The light exposure time for hydrogel photopolymerization by DLP bioprinting is optimized based on photorheometry and cell viability assays. Naturally immortalized bovine embryonic fibroblast cells transformed with MyoD and PPARγ2 instead of primary cells are used as the latter have difficulties in maintaining stemness and are associated with animal ethics issues. The cells are mixed into the hydrogel for printing. Myogenesis and adipogenesis are induced simply by changing the medium after printing. Scaffolds are obtained successfully with living cells and large microchannels. The cooked cultured meat maintains its size and shape upon cutting. The overall dimensions are 3.43 cm × 5.53 cm × 0.96 cm. This study provides proof-of-concept for producing 3D cultured meat using bioinks.