• Saanvi Jain

Bioprinting

Did you know that every day 17 people die because of their inability to get an organ transplant? A lot of the time, these people are unable to get an organ in time because of numerous reasons. Some of the common ones include the fact that the number of donors is significantly less than the demand for organs, unlikely matches, and the fast decaying rates of organs.

Fortunately, scientists, researchers, and medical experts have come up with an invention to help reduce this problem. Specifically, the solution to the problem is bioprinting. Bioprinting is a process similar to 3D printing. However, whereas 3D printing uses plastic, bioprinting uses cells and biomaterials. In this process, a digital file is used to print an organ or tissue layer by layer. Bioprinting has many applications and uses that have made it a ground-breaking discovery in science and medicine. Although one of the most prominent applications of it is the creation of artificial organs and tissue, it is also used for drug development, toxicology screening, wounds healing, and cancer research. The fabrication of various tissues such as skin tissue, bone and cartilage, blood vessels, and liver tissue has made recovery more feasible for many patients that have a hard time finding organs and tissue for transplants. In addition, due to organ donation lists being so long, many people end up dying or waiting for years. However, bioprinting has created a work-around for this. It is predicted that as bioprinting becomes more advanced and known, it will significantly decrease the need for organ donation. In addition, because tissue can be replicated in bioprinting, drug development can be simply more achievable. For drug testing, specific tissue is required to determine the efficacy and toxicity of a drug. Oftentimes, tissue is hard to come by because it is so rare and expensive since it is also on the basis of donation. Through bioprinting, acquiring tissue becomes cheaper and easier to access. Also, toxicity screenings can be done on bioprinted tissue instead of animals and humans. Not only does this make this type of screening easier to do, it also makes it more humane. Testing on animals tends to be cruel and sometimes against ethical codes. Bioprinting is a great solution to this problem. The test of cosmetic products and their toxicity can also be done on bioprinted tissue because the tissue will simulate real reactions on human skin such as skin corrosion, irritation, absorption, sensitization, and much more. Another great use of bioprinting is wound healing. There are a lot of clinical uses to bioprinting such as skin grafts and bone bandages due to the printing of artificial skin tissue, neurons, and liver cells. Lastly, bioprinting can be used for cancer research. In the past, cancer research has only been in 2D and studying it in 3D and live models can be very beneficial to understand it better. Bioprinting allows both pathogenesis, the manner of development of a disease, and metastasis, the development of secondary malignant growths, to be researched in more depth. Cells can be manipulated to simulate the conditions of cancer cells by controlling the cell-cell distance and cell density. Bioprinted tissue can also be used to study the efficiency of cancer treatments.

The basic process of bioprinting involves three steps — pre-bioprinting, bioprinting, and post-bioprinting. In pre-bioprinting, digital files are created using CT and MRI scans. Then, a live-cell imaging system is used to mix bioink and prepare cells. To prepare cells, first scientists select and multiply them. To keep them viable, nutrients and oxygen are mixed with the cell mass. Next is the bioprinting step. In this step, the bioink is put inside a cartridge and then placed inside a printer. This step in the process is quite complex because depending on the type of tissue or organ that needs to be formed, a cell type, the bioink, and the equipment is chosen. Lastly, post-bioprinting takes place. This process is to crosslink structures in order to make them more stable. To crosslink, structures are treated with either ionic solution or UV light. The ionic solution treatment is considered a chemical stimulation and the UV light treatment is considered a physical simulation. These stimulation treatments help signal the cells to maintain tissue growth and help them reorganize. Then, these structures are cultivated in an incubator until they are ready for use.

Thus, bioprinting is the future of medicine. However, much like most technology and inventions, bioprinting has its own challenges. Currently, bioprinting is only compatible with a select few biomaterials. In addition, the printing rate is extremely slow. Maintaining the printed tissue and organs also requires a great deal of maintenance. Because of the newness of it, bioprinting is quite expensive as of now and that may make it inaccessible to the poor, therefore, it may be unethical. It has also not been tested on humans enough so scientists are not sure if it is safe enough as of now. In the end, it is an amazing invention that will continue to improve as more scientists and researchers work on it.