A Gelatin Methacrylate-Based Hydrogel as a Potential Bioink for 3D Bioprinting and Neuronal Differentiation

Abstract

Neuronal loss is the ultimate pathophysiologic event in central nervous system (CNS) diseases and replacing these neurons is one of the most significant challenges in regenerative medicine. Providing a suitable microenvironment for new neuron engraftment, proliferation, and synapse formation is a primary goal for 3D bioprinting. Among the various biomaterials, gelatin methacrylate (GelMA) stands out due to its Arg-Gly-Asp (RGD) domains, which assure its biocompatibility and degradation under physiological conditions. This work aimed to produce different GelMA-based bioink compositions, verify their mechanical and biological properties, and evaluate their ability to support neurogenesis. We evaluated four different GelMA-based bioink compositions; however, when it came to their biological properties, incorporating extracellular matrix components, such as GeltrexTM, was essential to ensure human neuroprogenitor cell viability. Finally, GeltrexTM: 8% GelMA (1:1) bioink efficiently maintained human neuroprogenitor cell stemness and supported neuronal differentiation. Interestingly, this bioink composition provides a suitable environment for murine astrocytes to de-differentiate into neural stem cells and give rise to MAP2-positive cells.

Recent Advancements of Bioinks for 3D Bioprinting of Human Tissues and Organs

“…Furthermore, it could provide a suitable environment for the differentiation and generation of mouse astrocytes (Figure 6j). 89 Recent studies have shown that an increasing number of experiments have successfully integrated neural stem cells directly into bioprinted scaffolds without detrimental effects on cell survival and activity. Moreover, these studies have demonstrated the beneficial role of bioprinted scaffolds in The development of bioink and scaffolds is built upon in vitro experiments, aiming to promote neural cell differentiation and construct neural tissue.…”

“…The coagulated bioink, as shown in Figure i, supported the idea that human neural stem cells were successfully differentiated in immature neurons. Furthermore, it could provide a suitable environment for the differentiation and generation of mouse astrocytes (Figure j) …”

“…(h) SEM image of the 3D printed construct using the optimal ratio of bioink. Adapted with permission from ref . Copyright 2023, MDPI.…”

“…(i) Images of immunofluorescence staining using GFAP, TUBB3, and MAP2 markers on bioprinted hNPCs. Adapted with permission from ref . Copyright 2023, MDPI.…”

“…(j) Images of the expression of neuronal-specific markers (MAP2) to evaluate neurogenesis in mouse astrocytes. Adapted with permission from ref . Copyright 2023, MDPI.…”