Bioprinting is an emerging technology based on 3D printing for health that it enables the production of scaffolds with a homogeneous distribution of cells, materials/hydrogels and molecules throughout a scaffold.
This new technology has focused on studies involving the development and combination of biocompatible, biodegradable materials, inductive biomolecules, and cells or spheroids. Tissue spheroids or simply cell clusters can be produced by several techniques, with advantages such as high cell density, 3D structuring and the possibility of micro vascularization.
Tissue spheroids or simply cell aggregate can be produced by several techniques, with advantages such as high cell density, 3D structuring and the possibility of micro vascularization.
Bioprint technology has steps similar to 3D printing. It basically comes down to a pre-processing step, which requires a BioCAD / Blueprint or simply the tissue design for bioprinting. A second step called 3D processing or bioprinting using components such as cells or spheroids, synthetic materials or biomaterials, hydrogels and biomolecules. And the post-processing step which is the stage of maturation of the bioimpressed tissue. This last step requires equipment called bioreactors and is essential for the development of bio-printed tissue.
This scheme presents the relationship between tissue engineering, biofabrication, bioprinting and information technology.
There is a very important relationship among tissue engineering, biofabrication, bioprinting, and information technology. These technologies are excellent opportunities for the emergence of methods more advanced for biofabrication of functional organs.
“a formulation of cells suitable for processing by an automated biofabrication technology that may also contain biologically active components and biomaterials”
The challenges in the bioprinting of tissues and organs are numerous.
We can divide these challenges into technological, biological, chemical, physical, material, ethical and regulatory challenges.
Technological challenges are complex and need to be developed. While the area is new, many devices, software, and methods have been adapted and not properly created for bioprinting. Consequently, the integration and interoperability of files and systems have become a huge challenge.
The use of an adapted engineering method is routine, for example, the use of engineering software for the modeling of BioCAD, ie the design of the fabric that will be "biofabricated". We did not find computational programs and methods produced specifically for the development of complex tissues, and consequently, the area of biological modeling and simulation is very new and complex.
Systematic analysis (meta-analysis) or integrated platforms for evaluating biological processes can be called BioCAE, and may become the key to important steps in the processes of biofabrication and bioprinting of tissues.
BioCAE is a new computational approach to predict complex biological tissue systems using a combination of methods such as multiscalar mathematical modeling, computational simulations, functional biological data mining, simulation of structure, material and cell behavior, regulatory network machine learning, integrated with systems biology.
The cellular and tissue phenotype is essential for the understanding of tissue regeneration. Understanding the molecular networks of stem cells, adult cells, induced/edited cells and tissues is crucial for the development of new Bioprocesses and Bioproducts, such as biofabrication of tissues and in the future organs.
Of course, the use of computational methods such as BioCAE will help significantly in the development of Bioprocesses and Bioproducts, minimizing costs, time and use of animals.
Below, we have shown 3D printing concepts that are applied to all steps of 3D Bioprinting of tissues and organs, differing in accuracy, materials used and post-processing.
Tissues and organs "Bioprinted"
Recent trends in bioprinting research have shown its promising potential in the biofabrication of small tissue structures, organoids and in the future, complex organs. This technique offers advantages compared to conventional microfabrication methods, as well as, microscale, high manufacturing yield, and precise ability to dispense cells and tissue spheroids with high spatial and temporal resolution.
Although there has been a growing advance in the technologies involved in the field of 3D bioprinting, it is pertinent to affirm and reaffirm that no approach available today has the capacity to produce a fully functional organ, but it is not a fact impossible to happen in the future.
In recent years, much research has been done on bioprinting technology and its application in the generation of tissue analogs, including skin, heart valves, blood vessels, bones, cartilage, structures of the cornea, liver, thyroid and cardiac tissue.
Bioprinting is a hot area of research, with great promise in applications such as printing skin for burn victims and printing bone and cartilage for orthopedic repairs. But these research projects haven’t yet turned into real treatments for human patients.
Although there has been a growing advancement of technologies involved in the field of 3D bioprinting, it is pertinent to assert and reaffirm that no approach available today has the ability to produce a fully functional organ. Many studies are still needed for the evolution of this technology, especially the creation of interdisciplinary teams.
Bioprint is an emerging area that uses 3D printing technology for tissue and organ construction. 3D printing is an additive manufacturing technology (layer by layer) composed of few main steps, such as:
1- Modeling of the virtual model (CAD)
2- Image Slicing
3- 3D printing
4- Post processing
The equipment used for bioprinting tissues, and in the future organs, is called bioprinter. This equipment is similar to a 3D printer.
The main difference is the biological material that is used, being hydrogel, cells and biomolecules. The first step is the modeling of BioCAD (file with the structural organization of the biological components).
Many articles explain the use of tomography or resonance imaging for bioprinting, but we know that a significant amount of time is needed to study the histoarchitecture and composition of each tissue/organ.
The complexity, dynamicity of cells and the biological remodeling of their components are crucial for a functional tissue design. Today, we know that much more is needed than an organ's 3D structure file.
A multiscalar study of the tissue is necessary, for a better understanding of its systematic functionality - at the molecular, cellular and tissue level. The deposition stage of the biological material - cells, and biomolecules - is done with adequate strategies and is constantly improving to increase its accuracy.
This technology is already marketed, see some examples of bioprinters below.