Novel 3D glioblastoma model using extrusion based bioprinting system

The spatial organisation of cells such as cancer cells, fibroblasts and immune cells in defined matrix is essential to recapitulate the 3D complex architecture of tumour tissue. Current co-culture systems, 3D spheroids and organoids have contributed to understanding of diseases and drug response. However, the 3D models in general and specifically in glioma, yet to be tailored to depict the pathological relevant cell combination and complexity of tumour microenvironment. The application of extrusion based bio-printing approach allows 3D patterning of heterogeneous cell types in a predefined biomimetic manner. Here we present a robust printable 3D glioblastoma model with dimension of 3 mm in diameter and 1 mm in height. An alginate (4%)/ hyaluronic acid (5 mg/ml)/ collagen-1 (0.06 mg/ml) based hydrogel was used to embed U87MG or G144 glioma stem cells as a central core, with admix of macrophages and glioma patient derived fibroblasts in outer concentric circles. The alginate based 3D glioblastoma structure was crosslinked by covalent cations (Calcium chloride , 20 mM or Barium chloride, 20 mM) and was stable for weeks in cell culture medium. The viability of cells was verified in both 3D printing and pipetted approaches, and drug responses were compared among 2D culture, spheroids and 3D printed culture systems. The viability of printed and pipetted U87MG and G144 via cell dose response confirms no significant cell death. Stromal cells increase the proliferation of U87MG and G144 in 3D printed constructs compared to 3D spheroids and 2D culture system. The U87MG and G144 are significantly more sensitive to cisplatin and temozolomide in 2D than spheroid and 3D bio-printed constructs. This novel approach of onco-bioprinting is advancement over conventional 3D models, and should provide better biomimetic cancer tissue architecture to study the early diseases mechanism and drug screening.