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International Journal of Bioprinting Bioprinting organoids for toxicity testing

3. 3D-bioprinted functional pancreas or laminin mixtures did not affect the behavior of the cells
analyzed. A multilayer bioprinted structure of alginate
3.1. Bioprinted pancreatic islet structure bioink and polycaprolactone biodegradable polymer was
Precise bioprinting technology allows for the orientation encapsulated by beta cells (mouse insulinoma-6 [MIN-6])
of islet cells and supporting cells and the recapitulation (Figure 2C). In a study using a mouse model with type
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of the structural characteristics of natural islets. The islet 1 diabetes, the animals implanted with the bioprinted
cells, after bioprinting, maintain their physiological state structure showed a threefold increase in insulin secretion
in the bioink to ensure normal function, providing not and control of blood sugar levels 8 weeks after surgery
only a new tool for the study of pancreas-related diseases, (Figure 3).
but also strong support for the development of diabetes
treatment strategies. Through in-depth exploration of 3.3. In vitro islet bioprinting process and AI-based
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materials selection, cell distribution, scaffold design, and automation control
other factors in the construction process, this technology The cutting-edge applications of in vitro islet bioprinting
has made remarkable progress in the bioprinting of islet and AI-based automation control have been explored. At
structures, laying a solid foundation for future applications present, in vitro bioprinting of islets has made remarkable
in personalized medicine and tissue repair (Figure 2A). progress, as evident by the successful construction of islet
structures, but challenges in maintaining the functionality
3.2. Bioprinting of functional pancreatic islets and stability of islets remain. In the future, it is expected
The current 3D bioprinting technology can be used to that a higher degree of functional maintenance of the
construct the structure of the pancreatic islets, while bioprinted islets can be achieved by optimizing cell
maintaining their functions. Precise cell orientation and orientation, bioink formulation, and printing parameters.
bioink optimization allow for the maintenance of islet cells’ Artificial intelligence-based automation control has
normal endocrine functions during construction, including great potential in the field of bioprinting. By establishing
insulin secretion and glucose regulation. This achievement intelligent models, the printing process can be monitored,
promotes research in diabetes treatment, laying a solid analyzed, and adjusted in real time to improve accuracy
foundation for the development of personalized treatment and controllability.
strategies and biological tissue repair technologies, which
will further improve therapeutic accuracy and efficacy. The It has been demonstrated that artificial bionic islets
3D-bioprinted pancreatic islets can promote insulin secretion bioprinted from the stem cells derived from the pancreas
over a long period of time, and the structure is implanted of humans, rabbits, mice, etc. can produce insulin based
underneath the skin to prevent islet loss. Several recent on blood sugar levels like what the normal human organs
studies 44-46 have demonstrated the application of acellular do. In the long term, the 3D-bioprinted organs could
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extracellular matrix to these islets and tumor models. functionally replace the original pancreas. Different from
insulin injections, bioprinted pancreas can continuously
Pancreatic cancer is often used as a model for
developing new treatments, and pancreatic cancer cell lines produce insulin, significantly improving the quality of life of
patients. The pancreas contains many groups of specific cells,
exhibit different behaviors in their respective inks. Cellink and pancreatic cells generally refer to islet cells, including
bioinks consist of alginate and nanofiber cellulose, and one alpha cells, beta cells, pancreatic polypeptide cells, and delta
of which is coupled to RGD peptide (Cellink RGD). GelXA cells, which constitute the endocrine part of the pancreas and
bioinks are composed of gelatin methacrylate, xanthan are of great significance. At present, with the aid of computer-
gum, and alginate, and one of which is coupled to laminins aided design and computer-aided manufacturing, various
(GelXA LAMININK+). These modifications were chosen 3D bioprinting technologies can create highly similar 3D islet
because the expression of suitable integrin-like receptor structures with advanced functions. In addition, pancreatic
proteins is well described in malignant melanoma and has cancer cells can also be bioprinted to build in vitro pancreatic
been found to have an important role in tumor growth and cancer model, which can be used to test anti-tumor drugs,
progression. Matrigel is similar to the extracellular matrix examine their adverse reactions, and aid in the personalized
and is composed of type IV collagen, laminin, dentin, treatment of pancreatic cancer patients.
heparan sulfate proteoglycan, and growth factors. In
Matrigel, the cells are able to spread, proliferate, and form Tissue processing and cell culture during bioprinting
dense networks throughout the construction process, while dictate the quality of the resulting 3D-bioprinted structure.
in alginate-based bioinks, the cells do not proliferate at all. Taking human pancreas as an example, the purpose of
In a bioink based on methacrylate gelatin, cells proliferate cutting the tissue in the first step is to increase the contact
in clusters. Surprisingly, modifying the bioinks with RGD area between trypsin or collagenase and cells in the process

Volume 10 Issue 1 (2024) 129 https://doi.org/10.36922/ijb.1256