Perfusion culture‐induced template‐assisted assembling of cell‐laden microcarriers is a promising route for fabricating macrotissues

Abstract

Mass transfer limitation in conventional top-down tissue engineering makes it impossible to fabricate large size viable tissue replacements. In the present study, we aimed at performing a systemic investigation of the assembling process in perfusion culture for fabricating centimeter-scale macrotissues from cell-laden microcarriers following a bottom-up modular approach. Cells (human fibroblasts, human mesenchymal stem cells, or HepG2 cells) were seeded onto microcarriers (Cytopore-2 or CultiSpher S) in spinner flasks and cultured for 14 days and subsequently transferred to a perfusion chamber for assembling. It was found that growth of different cells on different microcarriers varied and aggregation of cell-laden microcarriers was favored with CultiSpher S. After perfusion culture for 14 days, while all microtissues could assemble into integral macrotissues, macrotissues of HepG2 cells were structurally most inferior and the assembling of cell-laden CultiSpher S led to a significant shrinkage. By designing perfusion chamber and using agar-based templates, tubular, disc, and alphabetic letter-shaped macrotissues could be easily fabricated, suggesting template-assisted assembling. Importantly, it was revealed that there existed both optimal perfusion culture time (21 days) and packing condition (1/4 compression) for the assembling of microtissues. This study lays a solid foundation for future applications of this microtissue assembling technique in tissue engineering.

Biophysical properties of dermal building-blocks affect extra cellular matrix assembly in 3D endogenous macrotissue

“…HD-μTP were fabricated by culturing human dermal fibroblasts within gelatine porous microbeads in a dynamic spinner culture [13,14]. 'We and others [13,39] have previously proved that, under such configuration, the interaction arising among fibroblasts and the surface of the gelatin microscaffolds, triggered mechanotransduction pathways involved in the collagen remodeling (synthesis-assembling-degradation). As a consequence, fibroblasts synthesized new collagen molecules that were then assembled within the pore spaces and on the surfaces of the gelatin microscaffold'.…”

Engineered microtissues for the bystander therapy against cancer

“…Cells are actively contributing to the formation of the bio-scaffold by proliferating and depositing ECM, creating a therapeutic MTs. MCs have already shown their potential for the construction of MTs for tissue engineering [63][64][65][66][67] or even fabricating in vitro tumors [68]. Whereas cell-derived ECM scaffolds have been used in different tissue regeneration approaches for bone, cartilage, liver, skin and vascular tissue among others [69].…”

Bioactive poly(ε-caprolactone) microspheres with tunable open pores as microcarriers for tissue regeneration

“…4 Previously, we had developed a novel process for engineering large bone tissue substitutes by culturing cells (mesenchymal stem cells, MSCs) on microcarriers (CultiSpher S) in scalable spinner flasks and then assembling these cell-laden microcarriers in a perfusion culture system. 5–8…”

“…4 Previously, we had developed a novel process for engineering large bone tissue substitutes by culturing cells (mesenchymal stem cells, MSCs) on microcarriers (CultiSpher S) in scalable spinner flasks and then assembling these cell-laden microcarriers in a perfusion culture system. [5][6][7][8] Microcarriers for cell culture are generally made of biodegradable polymers, such as synthetic polyesters including polycaprolactone (PCL), polylactic acid (PLA), polyglycolic acid (PGA), PLGA, as well as naturally derived molecules including collagen, chitosan, and alginate. 9 In addition, decellularized tissues, such as bone, can also be processed into microcarriers, which contain native bioactive molecules and can potentially provide a more favorable microenvironment for cells.…”