Tissue engineering, as the name suggests, is a science that develops synthetic biological substitutes capable of replacing diseased or damaged human tissue. In tissue engineering, biological components, such as cells and growth factors, are combined with engineering principles and synthetic materials. Human cells are seeded onto scaffolds made of collagen, a type of fiber, or biodegradable polymers, which are large molecules. Cells are stimulated by growth factors. The scaffolds are incubated with growth factors which promotes cell growth and division. When the cells spread over the scaffold, they provide a substitute for the original tissue. Implanting this tissue into the human body is possible, with the implanted scaffold being absorbed or dissolved by the body over time.
The goal of tissue engineering is to develop safe and reliable sources of tissues and organs for the replacement of damaged or diseased tissues and organs. Several advances and innovations are currently being made in the fields of tissue engineering and regenerative medicine that have a big impact on the three-dimensional bio-printing (3D bio-printing) of tissues and organs. 3D bioprinting holds great promise for artificial tissue and organ bioprinting, thereby revolutionizing the field of regenerative medicine. In order to perform 3D bioprinting and to use stem cells in therapeutic treatments, synthetic and natural biological molecules, such as growth factors, are needed. Recent research has shown that the use of these substances is causing severe side effects and toxicity, so scientists are looking for alternatives.
Currently available stimulants are mostly of non-human origin, so the body may reject them when they are used. Purified biological molecules are not only expensive, but they are also time-consuming to use. The US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) have approved a number of 3D-bioprinted constructs and stem cell therapies in the last decade. There are also medical devices and biopharmaceuticals to consider in addition to the therapies and products listed above. Despite this, most products are not able to resolve complex injuries or diseases entirely. There is a considerable delay involved in bringing new biomaterials and stem cell products to market mainly due to the number of policies required for FDA approval as well as the lack of monetary funding.