Encapsulation of pristine and silica-coated human adipose-derived mesenchymal stem cells in gelatin colloidal hydrogels for tissue engineering and bioprinting applications.

Colloidal gels assembled from gelatin nanoparticles (GNPs) as particulate building blocks show strong promise to solve challenges in cell delivery and biofabrication, such as low cell survival and limited spatial retention. These gels offer evident advantages to facilitate cell encapsulation, but research on this topic is still limited, which hampers our understanding of the relationship between the physicochemical and biological properties of cell-laden colloidal gels. Human adipose-derived mesenchymal stem cells were successfully encapsulated in gelatin colloidal gels and evaluated their mechanical and biological performance over 7 days. The cells dispersed well within the gels without compromising gel cohesiveness, remained viable, and spread throughout the gels. Cells partially coated with silica were introduced into these gels, which increased their storage moduli and decreased their self-healing capacity after 7 days. This finding demonstrates the ability to modulate gel stiffness by incorporating cells partially coated with silica, without altering the solid content or introducing additional particles. Our work presents an efficient method for cell encapsulation while preserving gel integrity, expanding the applicability of colloidal hydrogels for tissue engineering and bioprinting. Overall, our study contributes to the design of improved cell delivery systems and biofabrication techniques.

Microparticles orchestrating cell fate in bottom-up approaches.

The modulation of cells in tissue formation is still one of the hardest tasks to achieve in Tissue Engineering. To control the cell response when undergoing their normal functions such as adhesion, differentiation, assembly, or maturation is vital the development of more successful solutions. Herein, we discuss how microparticles are being overlooked in their potential for controlling the cellular response. Until now, their role was quite often restricted to a reservoir of chemical compounds or as carriers for cell expansion. Nevertheless, microparticles design with the introduction of biophysical and biochemical cues can effectively modulate cell response.