Hydrogels for Large-Scale Expansion of Stem Cells

Abstract

Stem cells show great promise for various pre-clinical and clinical applications, including drug screening, disease treatments, and regenerative medicine. In these applications, producing high-quality and large amount of stem cells is highly demanded. Despite challenging, with the development of hydrogel-based cell culture technology, tremendous progress has been made in stem cell expansion and directed differentiation. Hydrogels are soft materials with abundant water. Many hydrogel properties, including biodegradability, mechanical strength, and porosity have been shown to play essential roles in regulating stem cell proliferation and differentiation. The biochemical and physical properties of hydrogels can be specially tailored to mimic the native microenvironment that various stem cells reside in in vivo. A few hydrogel-based systems have been developed for successful stem cell culture and expansion in vitro. In this review, we summarize various types of hydrogels that have been designed to effectively enhance the proliferation of hematopoietic stem cells (HSCs), mesenchymal stem/stromal cells (MSCs), and pluripotent stem cells (PSCs), respectively. According to each stem cell type's preference, we also discuss the strategies for fabricating hydrogels of biochemical and mechanical cues and other characters representing the stem cells’ in vivo microenvironment.