A team of biomedical researchers, led by Michael Mak from the Renaissance School of Medicine at Stony Brook University, has developed a new bioprinting method called TRACE (Tunable Rapid Assembly of Collagenous Elements). This method addresses previous challenges in bioprinting natural body materials and is anticipated to advance drug development, disease modeling, and regenerative medicine.
The details of this method are outlined in a paper published in Nature Materials. Bioprinting involves positioning biochemicals, biological materials, and living cells to create bioengineered structures. It uses biological inks (bioinks) and biomaterials with computer-controlled 3D printing techniques to construct living tissue models for medical research. Although 3D printing technologies are relatively new to medicine and biomedical research, they have been widely used in industries like automotive manufacturing.
Researchers highlight that despite the potential of bioprinting, achieving functionality in bioprinted tissues and organs has been challenging. Biological cells in traditional bioprinted tissues often cannot perform their natural activities within the body, making most bioprinted tissues unsuitable for clinical purposes and advanced medical applications.
Mak and his colleagues believe TRACE will help address this issue in future medical research. "Our method is essentially a novel platform technology that can be used to print wide-ranging tissue and organ types," said Mak, an associate professor in the Department of Pharmacological Sciences. "With TRACE, we figured out how to fabricate and manufacture complex user-designable tissue and organ structures via 3D patterning and printing using the body’s natural building blocks, particularly collagen, as bioinks in a highly biocompatible manner and with direct incorporation of living cells."
Collagen, especially Collagen Type I, is a prominent protein in the human body. It acts as the "glue" for many tissues and organs and serves as the body's natural scaffolding material for holding cells and tissues in place. It also directs cells to perform their functions. Due to these attributes of collagen in physiological processes, it is considered an ideal candidate for use as a bioink material.
In their paper titled “Instant Assembly of Collagen for Tissue Engineering and Bioprinting,” the authors explain how TRACE allows them to rapidly accelerate the gelation process of collagen through macromolecular crowding—a process where an inert crowding material speeds up collagen molecule assembly reactions.
By employing this technique, they can create tissues composed of elements found inside the body. They apply TRACE to generate functional tissues and "mini organs" such as heart chambers.
Mak concludes: “TRACE offers a versatile biofabrication platform enabling direct 3D printing of physiological materials and living tissues achieving both structural complexity and biofunctionality. This work broadens the scope of controllable multiscale biofabrication for tissues across various organ systems using collagen as a key component.”