Recovery of Encapsulated Adult Neural Progenitor Cells from Microfluidic-Spun Hydrogel Fibers Enhances Proliferation and Neuronal Differentiation

Abstract

Because of the limitations imposed by traditional two-dimensional (2D) cultures, biomaterials have become a major focus in neural and tissue engineering to study cell behavior in vitro. 2D systems fail to account for interactions between cells and the surrounding environment; these cell−matrix interactions are important to guide cell differentiation and influence cell behavior such as adhesion and migration. Biomaterials provide a unique approach to help mimic the native microenvironment in vivo. In this study, a novel microfluidic technique is used to encapsulate adult rat hippocampal stem/ progenitor cells (AHPCs) within alginate-based fibrous hydrogels. To our knowledge, this is the first study to encapsulate AHPCs within a fibrous hydrogel. Alginate-based hydrogels were cultured for 4 days in vitro and recovered to investigate the effects of a 3D environment on the stem cell fate. Post recovery, cells were cultured for an additional 24 or 72 h in vitro before fixing cells to determine if proliferation and neuronal differentiation were impacted after encapsulation. The results indicate that the 3D environment created within a hydrogel is one factor promoting AHPC proliferation and neuronal differentiation (19.1 and 13.5%, respectively); however, this effect is acute. By 72 h post recovery, cells had similar levels of proliferation and neuronal differentiation (10.3 and 8.3%, respectively) compared to the control conditions. Fibrous hydrogels may better mimic the natural micro-environment present in vivo and be used to encapsulate AHPCs, enhancing cell proliferation and selective differentiation. Understanding cell behavior within 3D scaffolds may lead to the development of directed therapies for central nervous system repair and rescue.

Behavior of Neural Cells Post Manufacturing and After Prolonged Encapsulation within Conductive Graphene-Laden Alginate Microfibers

“…[16] Its structure of M- and G-blocks can be ionically crosslinked in the presence of divalant cations, such as Ca 2+ , Ba 2+ , Sr 2+ , and others; however, calcium crosslinkers are commonly used in biomedical applications because they are readily available and cost effective, and because calcium alginate hydrogels exhibit good swelling properties, which is important to maintain cell viability. [5, 6, 9, 35]…”

Recent Progress in Preparation and Application of Fibers Using Microfluidic Spinning Technology

“…Cell Scaffold: Under certain circumstances, microfluidic fibers are beneficial to cell proliferation and conducive to guiding cell alignment. [70][71] Alginate-GelMA hydrogel microfibers with various structures, such as single-layer, double-layer, and hollow shape were fabricated without a great change of the microfluidic set-up (the composition of solution used in the core stream and sheath stream was nearly the same for different structures). [72] The biocompatible hydrogel microfibers with the single-layer structure were seeded with mouse embryonic osteoblast precursor cells (MC3T3-E1) or human umbilical vein endothelial cells (HUVECs), while microfibers with double-layer and hollow structures were encapsulated with MC3T3-E1 cells and HUVECs, re-spectively.…”

Targeted Microfluidic Manufacturing to Mimic Biological Microenvironments: Cell-Encapsulated Hollow Fibers

“…25 TUBB-3 levels were suppressed after the addition of alginate, which was also observed in past works on adult hippocampal progenitor stem cells using immunocytochemistry to study β-III tubulin levels. 30 Since TUBB-3 is related neurogenesis and formation of the cytoskeleton, downregulation in these samples indicates that alginate negatively affects cells' ability to perform healthy cellular activities. This is a trend that is continued in encapsulated cells, indicating that the encapsulation process and the situation within the microfibers further inhibits neurogenesis and cytoskeleton formation.…”