A new 3D printing technique allows researchers to replicate biological structures that could be used for tissue regeneration and replica organs.
Structure of a single unit; how eight units fit together; two views of a printed and set eight-unit structure. Source: Imperial College London
Researchers from the Imperial College London have developed this new method that created 3D structures using cryogenics and 3D printing techniques.
This technique builds on previous research, although it is the first to create structures that are soft enough to mimic the mechanical properties of organs like the brain and lungs.
Being able to match the structure and softness of body tissues means that these structures could be used in medical procedures to form scaffolds that can act as a template for tissue regeneration, where damaged tissues are encouraged to regrow.
Regenerating damaged tissue by "seeding" porous scaffolds with cells and encouraging them to grow allows bodies to heal without the issues that tissue-replacing transplant procedures are normally affected by, like the body rejecting the tissue.
The use of scaffolds is becoming common, but the new technique is special because it creates super-soft scaffolds that help promote regeneration. In particular, there may be future potential in seeding neuronal cells, like those involved in the brain and spinal cord.
The researchers tested the 3D printed structures by seeding them with dermal fibroblast cells, which generated connective tissue in the skin. They found that there were successful attachment and survival. The success could lead to further possibilities around the successful growth of stem cells, which is medically exciting due to their ability to change into different types of cells.
The technique could also be used to create replica body parts or even whole organs. These could be useful to scientists to use in experiments that are not possible on live subjects. They could be used to help with medical training, replacing the need for animal bodies for students to practice surgery on.
Zhengchu Tan, a researcher from the Department of Mechanical Engineering at Imperial, "At the moment we have created structures a few centimeters in size, but ideally we'd like to create a replica of a whole organ using this technique."
The technique uses solid carbon dioxide to rapidly cool a hydrogel ink as it is extruded from a 3D printer. After being thawed, the gel is as soft as body tissues but doesn’t collapse under its own weight, which has been a problem for similar techniques in the past.
Dr. Antonio Elia Forte, one of the researchers from the Department of Bioengineering at Imperial, said, "Cryogenics is the novel aspect of this technology — it uses the phase change between liquid and solid to trigger polymerization and create super soft objects that can hold their shape. This means that the technology has a wide variety of possible uses."
The paper on this research was published in Scientific Reports.
