Tissue engineered model of neuroblastoma. (a) Generation of pre-vascularized sheets of neuroblastoma cells using temperature-responsive poly(N-isopropylacrylamide)(PIPAAm)-grafted culture plates. Bright field image shows a co-culture of SKNBE(2) and HUVEC cells growing on top of temperature-responsive plates at day 3 (Scale bar: 100 µm). (b) Formation of cell aggregates and cell-aligned structures in neuroblastoma cell sheets at day 3, by Scanning Electron Microscopy (SEM) (Scale bar: 25 µm). (c) Evaluation of cell-sheet pre-vascularization, cellular composition and cell proliferation by AZAN, CD31, NMYC and Ki67 staining of 3-layered SKNBE(2)/HUVEC cell sheets at day 3 (Scale bar: 100 µm). (d) Scheme of assembly of the tissue-engineered model of Neuroblastoma(NB). A pre-vascularized 3-layered NB/HUVEC cell sheet is stacked with fibrin and then, it is placed on top of the vascular bed. The vascular bed is made of fibrin, collagen I and HUVEC cells and generated on top of a collagen-gel base. (e) Culture device. The tissue-engineered tumor model is generated in situ atop a collagen-gel base with 8 microchannels in the culture device. (f) The tissue-engineered tumor model is cultured in the bioreactor culture chamber under perfusion (0.5 mL/min) established by a syringe pump, with monitoring of oxygen and pH in culture medium. (g) Computer simulation of the concentration profiles inside the tumor model, using glucose as a marker molecule. The concentrations levels are color-coded. (i) Cross-section view. (ii) The top surface.