In-lab three-dimensional printing: an inexpensive tool for experimentation and visualization for the field of organogenesis

Abstract

The development of the microscope in 1590 by Zacharias Janssenby and Hans Lippershey gave the world a new way of visualizing details of morphogenesis and development. More recent improvements in this technology including confocal microscopy, scanning electron microscopy (SEM) and optical projection tomography (OPT) have enhanced the quality of the resultant image. These technologies also allow a representation to be made of a developing tissue's three-dimensional (3-D) form. With all these techniques however, the image is delivered on a flat two-dimensional (2-D) screen. 3-D printing represents an exciting potential to reproduce the image not simply on a flat screen, but in a physical, palpable three-dimensional structure. Here we explore the scope that this holds for exploring and interacting with the structure of a developing organ in an entirely novel way. As well as being useful for visualization, 3-D printers are capable of rapidly and cost-effectively producing custom-made structures for use within the laboratory. We here describe the advantages of producing hardware for a tissue culture system using an inexpensive in-lab printer.

Figure 1. Embryonic mouse kidney imaged using OPT. The image stack was then imported to a commercially available image segmentation package (ScanIP). Threshold and segmentation techniques were then applied to reconstruct a surface mesh of the ureteric tree. Smoothing and island removal tools were applied to the mesh to reduce artifacts at the transition between image slices, and to remove unconnected regions in the model that may pose problems when printing. The final mesh of the embryonic kidney was then saved and exported in the .stl format. Further repairs and clean up/simplification of the kidney surface as required were performed using freely available open source packages such as MeshLab and netfabb. The final .stl file containing the embryonic kidney geometry was then imported into the companion software package of the 3-D printer (Axon2, BitsfromBytes).

Figure 2. Branching ureteric tree from an E15.5 mouse kidney printed in red ABS plastic, demonstrating the extensive white PLA support scaffold required.

Figure 3. Red ABS printed branching ureteric tree from an E15.5 mouse kidney with support structure removed. The branching pattern is clearly seen and can be explored in three dimensions.

Figure 4. TinkerCad (top left) and netfabb (top right) screen shots showing .stl file generation and “clean-up” process respectively. Bottom photo: the ABS culture support grids printed from this file.

Figure 5. Close-up of tissue culture support grid (left). Grid in use supporting four E11.5 mouse small bowels in culture (right).