Affiliation: | 1. College of Biological Science and Medical Engineering, Donghua University, Shanghai, 201620 China Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, 68198 USA Mary & Dick Holland Regenerative Medicine Program, University of Nebraska Medical Center, Omaha, NE, 68198 USA;2. Mary & Dick Holland Regenerative Medicine Program, University of Nebraska Medical Center, Omaha, NE, 68198 USA Department of Surgery, University of Nebraska Medical Center, Omaha, NE, 68198 USA;3. Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, 68198 USA Mary & Dick Holland Regenerative Medicine Program, University of Nebraska Medical Center, Omaha, NE, 68198 USA;4. Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE, 68198 USA;5. Department of Biochemistry and the Redox Biology Center, University of Nebraska-Lincoln, Lincoln, NE, 68588 USA;6. Department of Nutrition, University of Massachusetts Amherst, Amherst, MA, 01003 USA;7. Mary & Dick Holland Regenerative Medicine Program, University of Nebraska Medical Center, Omaha, NE, 68198 USA Department of Genetics, University of Nebraska Medical Center, Omaha, NE, 68198 USA;8. Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, 68198 USA |
Abstract: | Porous alginate (Alg) hydrogels possess many advantages as cell carriers. However, current pore generation methods require either complex or harsh fabrication processes, toxic components, or extra purification steps, limiting the feasibility and affecting the cellular survival and function. In this study, a simple and cell-friendly approach to generate highly porous cell-laden Alg hydrogels based on two-phase aqueous emulsions is reported. The pre-gel solutions, which contain two immiscible aqueous phases of Alg and caseinate (Cas), are cross-linked by calcium ions. The porous structure of the hydrogel construct is formed by subsequently removing the Cas phase from the ion-cross-linked Alg hydrogel. Those porous Alg hydrogels possess heterogeneous pores ≈100 µm and interconnected paths. Human white adipose progenitors (WAPs) encapsulated in these hydrogels self-organize into spheroids and show enhanced viability, proliferation, and adipogenic differentiation, compared to non-porous constructs. As a proof of concept, this porous Alg hydrogel platform is employed to prepare core-shell spheres for coculture of WAPs and colon cancer cells, with WAP clusters distributed around cancer cell aggregates, to investigate cellular crosstalk. This efficacious approach is believed to provide a robust and versatile platform for engineering porous-structured Alg hydrogels for applications as cell carriers and in disease modeling. |