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International Journal of Bioprinting dECM bioink for in vitro disease modeling

bioreactor can be minimized, allowing for generation of substitutes. 88,231 Nonetheless, augmenting dECM bioink
results that are highly reflective of the actual situation of with other hydrogels is considered a reasonable strategy
respiratory system. for improving the printability of the bioink through the
improvement of its physical properties, and there are
5. Conclusions and future perspectives attractive methods for accomplishing this integration. 232,233

To create 3D structure and to simulate pathology-specific For example, Ali et al. improved the physical properties of
microenvironment in a disease model, it is important to a bioink using a methacrylated-dECM bioink and applied
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select appropriate biomaterials and model manufacturing it to kidney regeneration, whereas Kim et al. developed
methods. From this perspective, the combination a light-activated dECM bioink and successfully fabricated
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of dECM as a biomaterial and 3D bioprinting as a centimeter-scale 233 structures using extrusion-based
manufacturing method is currently a promising approach 3D bioprinting. These methods, which leverage the
to fabricate disease models. First, 3D bioprinting can be advantage of dECM bioink, can be used to fabricate stable
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used to process various cells and biomaterials that constitute 3D structures to improve their mechanical properties while
organs into shapes suitable for creating pathophysiological maintaining their characteristics essential for creating
structures. 3D bioprinting can create in vitro and in vivo tissue-specific microenvironment.
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models that precisely mimic the structures and functions of To maximize the utilization of the enhanced dECM
human organs via the spatial placement of cell-containing bioink through the previously mentioned methods in
bioink. To maximize the advantages of 3D bioprinting, various applications, the versatility of 3D bioprinting
it is important to select an appropriate biomaterial that technology itself is essential. To develop more diverse
can create the microenvironment of the disease model. disease models and to fabricate large-volume structures
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Therefore, employing dECM as a bioink to reproduce the for tissue regeneration, it is necessary to improve
ECM composition specific to a given organ has considerable fabrication technology, in terms of fabrication time and
potential for simulating the pathophysiological precision, using advanced dispensers and nozzles. These
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microenvironment of a disease. 3D-bioprinted disease requirements can be fulfilled by adopting a combination
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models created with dECM bioinks have demonstrated the of existing 3D bioprinting technologies. For example,
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potential for pathophysiological mechanism studies, tissue Brassard et al. successfully generated macroscale
regeneration, and drug screening for various diseases. tissue blocks using a combination of extrusion-based
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However, widespread application of 3D bioprinting using and inkjet bioprinting techniques. Moreover, it is
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dECM bioinks is limited by several challenges. Some of difficult to accurately control the printing conditions
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these challenges associated with dECM and 3D bioprinting of a conventional 3D bioprinting system in real time,
for the fabrication of various disease models are discussed such as temperature and humidity, setting the stage for
as follows. Approaches to overcome these problems are problems in the precision of structure manufacturing
also proposed. Additionally, ethical and legal issues related using dECM. Therefore, it is necessary to establish a
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to 3D bioprinting and dECM bioink are briefly addressed. printability database for dECM bioinks and to apply real-
time automatic control to printing systems.
Biomaterials suitable for 3D bioprinting must possess
specific physical properties to ensure mechanical stability of Other challenges related to dECM bioinks include
the printed structure. In the case of hydrogels, for example, reproducibility and standardization issues. The toxicity
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their restricted crosslinking limits their applicability as of agents used for decellularization and incomplete cell
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bioinks. Therefore, to have a high degree of freedom in 3D removal have also emerged as additional problems. The
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bioprinting, it is necessary to develop advanced biomaterials dECM is an attractive biomaterial for tissue regeneration
with controllable physical properties through the chemical and disease models because it can be used to create tissue-
or physical treatment of conventional biomaterials. specific microenvironments. However, the dECM
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Regarding dECM, its important property is that it can composition changes slightly from batch to batch, resulting
simulate an organ-specific microenvironment. However, in functional differences. To address this problem,
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despite their biochemical superiority, dECM bioinks have standardization of the material preparation process is
insufficient mechanical properties to fabricate various required. There is a method for decellularizing large
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structures with high resolution. One possible supportive amounts of tissue to produce large amounts of dECM at
method that addresses this limitation is the integration once and mixing it. A thorough analysis of all components
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of a hydrogel with a polymer, such as polycaprolactone of each organ-derived dECM lays a foundation for the
(PCL) and polyethylene-vinyl acetate (PEVA), to enhance quantitative standardization of their composition, which is
structural integrity; however, plastic scaffolds may limit instrumental for the creation of a more potent and uniform
the usage of printed analogs in the context of native tissue biological material. Furthermore, animal-derived dECM

Volume 10 Issue 2 (2024) 151 doi: 10.36922/ijb.1970