Bioprintable Alginate/Gelatin Hydrogel 3D <em>In Vitro</em> Model Systems Induce Cell Spheroid Formation

Abstract

The cellular, biochemical, and biophysical heterogeneity of the native tumor microenvironment is not recapitulated by growing immortalized cancer cell lines using conventional two-dimensional (2D) cell culture. These challenges can be overcome by using bioprinting techniques to build heterogeneous three-dimensional (3D) tumor models whereby different types of cells are embedded. Alginate and gelatin are two of the most common biomaterials employed in bioprinting due to their biocompatibility, biomimicry, and mechanical properties. By combining the two polymers, we achieved a bioprintable composite hydrogel with similarities to the microscopic architecture of a native tumor stroma. We studied the printability of the composite hydrogel via rheology and obtained the optimal printing window. Breast cancer cells and fibroblasts were embedded in the hydrogels and printed to form a 3D model mimicking the in vivo microenvironment. The bioprinted heterogeneous model achieves a high viability for long-term cell culture (> 30 days) and promotes the self-assembly of breast cancer cells into multicellular tumor spheroids (MCTS). We observed the migration and interaction of the cancer-associated fibroblast cells (CAFs) with the MCTS in this model. By using bioprinted cell culture platforms as co-culture systems, it offers a unique tool to study the dependence of tumorigenesis on the stroma composition. This technique features a high-throughput, low cost, and high reproducibility, and it can also provide an alternative model to conventional cell monolayer cultures and animal tumor models to study cancer biology.

Cell Culture Based in vitro Test Systems for Anticancer Drug Screening

“…An interesting approach is the combination of several types of cells, tumor and stromal, in a 3D bioprinting model. Breast cancer cells and fibroblasts cultured in 3D bioprinting spheroids as part of an alginate-gelatin hydrogel maintained viability for more than 30 days and were resistant to paclitaxel, which was not observed in 3D bioprinting monocultures of breast cancer cells (Jiang et al, 2018). The trophic role of stromal or immune cells has been shown in other studies.…”

3D printing of tissue engineering scaffolds: a focus on vascular regeneration

“…Besides, hanging-drop approach by inverting cell-seeding plates is another feasible method [ 60 ]. Both matrices and microchannels can be fabricated by 3D printing-based methods [ 1 , 61 ]. Although scaffold-free approaches are also advancing, there are inescapable aspects in vascularized tissue engineering, where scaffold-based methods are better than the scaffold-free methods.…”

Recent trends in protein and peptide-based biomaterials for advanced drug delivery

“…In vivo, inhibition of tumor growth was similar for hydrogels containing a low dose of cisplatin and conventional intraperitoneal administration of high doses of free cisplatin [ 306 ]. Kinsella and colleague fabricated various alginate-gelatin bio-printable composite hydrogels that resemble the microscopic architecture of native tumor stroma [ [307] , [308] , [309] ]. 3D-printed hydrogels embedded with breast cancer cells, and fibroblasts promoted the self-assembly of breast cancer cells into multicellular tumor spheroids (MCTS), which were viable for more than 30 days [ 307 ].…”