Bioprinting: Fundamentals and Applications (Bioprinting: Fundamentals and Applications)

Additive manufacturing enables the generation of highly complex geometries with high flexibility compared to traditional manufacturing technologies and has received increasing attention in many fields, including biomedical engineering. Recent advances in additive manufacturing applied to biomaterials and cells resulted in an emerging technology: Bioprinting. This technology exploits the technical advancements of additive manufacturing to precisely position cells in a 3D environment to recapitulate the biochemical and biophysical properties of native tissue. In this way, 3D in vitro models of specific tissues/organs are created, which can be used for disease modeling and drug screening. The possibility of using human cells makes these models physiologically relevant and, in some aspects, more predictive of the human response to e.g. drugs than the usually employed animal models. Biologically functional models can be generated by the structural organization of living cells, bioactive molecules and biomaterials, through various bioprinting technologies, such as extrusion- and inkjet-based processes or laser-induced forward transfer. With applications ranging from disease modeling, drug discovery to personalized medicine and investigation of fundamental biological mechanisms, bioprinting is a fast-progressing field, gaining relevance in high-impact translational work as well as showing tremendous potential for various industrial applications.
The module “Bioprinting” provides an overview of this multidisciplinary research area and the knowledge in bioprinting technologies, bioinks, 3D in vitro models and organoids. The course starts with an overview of the historical developments and the general motivation to manufacture biologically functional tissue. Next, established extrusion-, droplet- and laser-based bioprinting technologies as well as emerging approaches (e.g. microfluidic bioprinting, volumetric bioprinting) are discussed with respect to their advantages and disadvantages, and fields of application. The course highlights the printing parameters as well as methods to assess extrudability and shape fidelity. Fundamental basics in cell culture are introduced to understand the general biological requirements as well as design criteria for bioinks to encapsulate cells. To familiarize students with translational aspects, the course discusses the regulatory considerations for bioprinting processes and products. The course will explain technical as well as interdisciplinary competences, which are not only relevant to the field of bioprinting, but also relevant for biomedical engineering in general.

The following topics are covered in this module (subjected to change):
• Introduction to bioprinting: historical developments, motivation and applications
• Definition and comparison of state-of-the-art bioprinting technologies
• Introduction to basics cell culture and stem cells
• Classification and design criteria for bioinks
• Fundamentals and applications of crosslinking methods in bioprinting
• Methods to evaluate the extrudability, shape fidelity, and printing accuracy
• Methods to assess cell viability and proliferation
• In vitro 3D models of human tissue/organs and organoids: biofabrication and potential
• Translational applications and future challenges
• Regulatory considerations for processes and products

After successful participation in the module "Bioprinting", the students are able to
• understand the operating principles of bioprinting technologies
• evaluate the existing bioprinting technologies and their specific advantages and disadvantages
• demonstrate an understanding of the design criteria for bioinks and formulate bioink specifications for bioprinting technologies and application areas
• describe methods to assess cell viability and proliferation
• analyze current challenges in the field of biofabrication
• formulate regulatory consideration for processes and products

none

The module consists of a lecture, an exercise, and a tutorial. If in-person teaching is not possible, an online format will be chosen that guarantees active exchange with the lecturers and log-in data will be shared with the students at the beginning of the semester. Materials and additional information are available online to all registered students in a digital format via the Moodle eLearning platform. Questions and answers (Q&A) sessions are offered to clarify topics presented in the lectures and to further deepen aspects of interest upon students’ request. The exercise will strengthen the theoretical knowledge provided in the lectures. Students will solve and discuss problems related to the field of bioprinting, and learn to implement the taught concepts to exemplary applications. The exercises are an essential format to help the students to acquire the teaching goals of this module. In addition to the lecture and exercise, tutorials are organized to provide the students with the opportunity to ask the lecturers specific questions individually or in small groups. Tutorials will close knowledge gaps and and will allow to explore individual areas of interest in greater detail.

Presentations, handouts, videos, online teaching materials, case study descriptions

[1] Murphy, S. V., Atala, A. (2014). 3D bioprinting of tissues and organs. Nature biotechnology, 32(8), 773-785.
[2] Sun, W. et al. (2020). The Bioprinting Roadmap. Biofabrication, 12(2), 022002.
[3] Moroni, L., et al (2018). Biofabrication: a guide to technology and terminology. Trends in biotechnology, 36(4), 384-402.
[4] Groll, J., et al. (2016). Biofabrication: reappraising the definition of an evolving field. Biofabrication, 8(1), 013001.
[5] Bedell, M. et al. (2020). Polymeric systems for bioprinting. Chemical Reviews, 120(19), 10744-10792.
[6] Schwab, A. et al. (2020). Printability and shape fidelity of bioinks in 3D bioprinting. Chemical Reviews, 120(19), 11028-11055.
[7] Levato, R., et al. (2020). From shape to function: the next step in bioprinting. Advanced Materials, 32(12), 1906423.

The learning outcomes will be examined in a written test (duration: 90 min). This test will assess the degree of understanding in the field of bioprinting, specifically, whether the students are familiar with the operating principles of bioprinting technologies and design criteria for bioinks as well as the corresponding applications to mimic human tissue and organs. Students have to demonstrate their ability to critically evaluate and solve problems for bioprinting applications. This also includes regulatory considerations for the processes and products.

Resources for the exam: none (except writing materials)