Cell sheet based bioink for 3D bioprinting applications

Abstract

In this research, a novel development of bioink from cell sheets is presented for scaffold free bioprinting applications. Poly(N-isopropylacrylamide) (PNIPAAm) coated surfaces were first prepared by using initiated chemical vapor deposition method. Cell-sheets were then grown on these thermoresponsive pNIPAAm coated surfaces and easily detached without disturbing delicate cell-extracellular matrix (ECM) and cell-cell interactions. The detached cells sheets were used to prepare cell sheet based bioink and bioprinted to form various shapes. The results showed that the prepared cell-sheet based bioink shows an increase in the structural integrity compare to cell-aggregates suggesting that the cell sheet aggregates preserved interconnected ECM proteins. The viability of cell sheet based aggregates was also compared to single cell aggregates at three different time points in a seven-day period after printing. The developed cell-sheet based bioink has several advantages in terms of shape fidelity, reproducibility and automated deposition for bioprinting applications. The results also demonstrated that the bioprinted constructs secreted collagen type I which is a strong indication of starting ECM deposition. Moreover, the immunostaining results showed that the fibronectin in cell sheets was preserved during and after the preparation process of bioink.

3D Printing of Mechanically Stable Calcium‐Free Alginate‐Based Scaffolds with Tunable Surface Charge to Enable Cell Adhesion and Facile Biofunctionalization

“…Supporting materials are commonly used in 3D‐printing to realize complicated structures, especially in the creation of overhanging and hollow shapes within scaffolds, but later dispose of the supporting material is usually necessary. [4d,19] The successful fabrication of bone‐shaped scaffolds on a large scale demonstrated the excellent self‐supporting ability of the designed Alg/ε‐PL bioink, as shown in Figure C; the actual printing process was recorded in Movie S1 in the Supporting Information. Furthermore, tubular scaffold was also successfully fabricated by a coaxial printhead (inner radius: 0.7 mm, outer radius: 1.5 mm) to confirm the Alg/ε‐PL bioink with excellent printability and self‐supporting ability.…”

“…This should be due to the limitations in terms of current biomaterial availably used as bioinks in 3D printing . Thus, the development of a suitable bioink with printability, biodegradability, biocompatibility, and mechanical strength with simultaneous facile bioactive functionalization properties is highly desirable to fabricate personalized scaffolds that can ideally be tailored to regenerate undefined tissue defects …”

Advanced Bottom‐Up Engineering of Living Architectures

“…Apart from controlling cell distribution and harvesting in in vitro cultured substrates, cell sheets have also been recently processed as scaffolds‐free 3D bioinks. Using an elegant approach, researchers used extrusion bioprinting to fabricate sheet‐based constructs that showed an increased structural integrity in comparison to standard cell‐aggregates owing to their in vitro produced ECM …”

Enabling personalized implant and controllable biosystem development through 3D printing

“…A cell sheetbased bioink preparation method was demonstrated in which the cells were proliferated on poly(Nisopropylacrylamide) (PNIPAAm) coated surfaces and then were used as a bioink for 3D bioprinting. (Bakirci et al, 2017) In addition, a method in which the cellular components of a tissue are removed to form a decellularized ECM bioink (dECM) by the physical, chemical and enzymatic processes has been recently developed. The 3D Bioprinting is performed with this material containing encapsulated living stem cells.…”