Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA; Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Biomaterials. 2022 Aug;287:121669. doi: 10.1016/j.biomaterials.2022.121669. Epub 2022 Jul 12.
Cultured meat has potential to diversify methods for protein production, but innovations in production efficiency will be required to make cultured meat a feasible protein alternative. Microcarriers provide a strategy to culture sufficient volumes of adherent cells in a bioreactor that are required for meat products. However, cell culture on inedible microcarriers involves extra downstream processing to dissociate cells prior to consumption. Here, we present edible microcarriers that can support the expansion and differentiation of myogenic cells in a single bioreactor system. To fabricate edible microcarriers with a scalable process, we used water-in-oil emulsions as templates for gelatin microparticles. We also developed a novel embossing technique to imprint edible microcarriers with grooved topology in order to test if microcarriers with striated surface texture can promote myoblast proliferation and differentiation in suspension culture. In this proof-of-concept demonstration, we showed that edible microcarriers with both smooth and grooved surface topologies supported the proliferation and differentiation of mouse myogenic C2C12 cells in a suspension culture. The grooved edible microcarriers showed a modest increase in the proliferation and alignment of myogenic cells compared to cells cultured on smooth, spherical microcarriers. During the expansion phase, we also observed the formation of cell-microcarrier aggregates or 'microtissues' for cells cultured on both smooth and grooved microcarriers. Myogenic microtissues cultured with smooth and grooved microcarriers showed similar characteristics in terms of myotube length, myotube volume fraction, and expression of myogenic markers. To establish feasibility of edible microcarriers for cultured meat, we showed that edible microcarriers supported the production of myogenic microtissue from C2C12 or bovine satellite muscle cells, which we harvested by centrifugation into a cookable meat patty that maintained its shape and exhibited browning during cooking. These findings demonstrate the potential of edible microcarriers for the scalable production of cultured meat in a single bioreactor.
培养肉具有使蛋白质生产方法多样化的潜力，但需要提高生产效率方面的创新，才能使培养肉成为可行的蛋白质替代品。微载体为在生物反应器中培养大量贴壁细胞提供了一种策略，这些细胞是生产肉类产品所必需的。然而，在不可食用的微载体上进行细胞培养，在食用之前需要额外的下游处理来使细胞分离。在这里，我们提出了可食用的微载体，它可以在单个生物反应器系统中支持肌源性细胞的扩增和分化。为了用可扩展的工艺制造可食用的微载体，我们使用油包水乳液作为明胶微球的模板。我们还开发了一种新的压印技术，在可食用的微载体上压印具有凹槽拓扑结构的图案，以测试具有条纹表面纹理的微载体是否可以促进悬浮培养中的成肌细胞增殖和分化。在这个概念验证演示中，我们表明，具有光滑和有凹槽表面拓扑结构的可食用微载体都支持悬浮培养中的鼠源性 C2C12 成肌细胞的增殖和分化。与在光滑的球形微载体上培养的细胞相比，具有凹槽的可食用微载体上的成肌细胞增殖和排列略有增加。在扩展阶段，我们还观察到在光滑和有凹槽的微载体上培养的细胞形成细胞-微载体聚集体或“微组织”。在光滑和有凹槽的微载体上培养的成肌微组织在肌管长度、肌管体积分数和成肌标志物表达方面表现出相似的特征。为了确定可食用微载体用于培养肉的可行性，我们表明，可食用微载体支持 C2C12 或牛卫星肌肉细胞产生成肌微组织，我们通过离心将其收获到可烹饪的肉饼中，该肉饼在烹饪过程中保持形状并呈现褐色。这些发现证明了可食用微载体在单个生物反应器中规模化生产培养肉的潜力。
