Engineered streaky pork by 3D co-printing and co-differentiation of muscle and fat cells

Cultured meat has attracted widespread interest and research due to its sustainable meat production through innovative technologies. Recently, studies have been carried out on manufacturing muscle or fat tissue for application in cultured meat, but it remains a challenge to engineer and produce cultured meat integrating both muscle and fat tissues. Herein, it is aimed to simultaneously assemble porcine muscle stem cells (pMuSCs) and adipose-derived mesenchymal stem cells (pAMSCs) by 3D bioprinting and to develop a co-differentiation approach to manufacture cultured streaky pork (CSP) with well-defined muscle and fat compositions. Previously, we have fabricated a collagen-chitosan composite hydrogel that efficiently supported the 3D proliferation and differentiation of pMuSCs. In this work, we first determined a composite hydrogel consisting of fibrinogen and sodium alginate for the 3D culture of pAMSCs. Next, for the two bioinks encapsulating pMuSCs and pAMSCs, respectively, we obtained the optimal cell loading number and printing parameters (pressure and speed) of an extrusion bioprinter and developed a co-differentiation approach that induced both myogenic differentiation of pMuSCs and adipogenic differentiation of pAMSCs. Furthermore, we fabricated meat-like 3D constructs by co-printing two bioinks and then induced both myogenesis and adipogenesis with the co-differentiation approach, thereby producing CSP containing both muscle and fat tissues. The textural and nutritional assessment demonstrated that the CSP possessed the cooking properties and eating qualities of meat products. This work provides innovative strategies and technical references for the production of cultured meat with tissue composition and spatial structure closer to real meat.