This book is a printed edition of the Special Issue "Advances in Micro-Bioreactor Design for Organ Cell Studies" that was published in Bioengineering

Recent advances in microsystems technology and cell culture techniques have led to the development of organ-on-chip microdevices that produce tissue-level functionality, not possible with conventional culture models, by recapitulating natural tissue architecture and microenvironmental cues within microfluidic devices. Since the physiological microenvironments in living systems are mostly microfluidic in nature, the use of microfluidic devices facilitates engineering cellular microenvironments; the microfluidic devices allow for control of local chemical gradients and dynamic mechanical forces, which play important roles in cellular viability and function. The organ-on-chip microdevices have great potential to promote drug discovery and development, to model human physiology and disease, and to replace animal models for efficacy and toxicity testing. Recently, induced pluripotent stem (iPS) cells have been leveraged to develop organs-on-chips, which enable various types of organ models and disease models not possible with primary cells and cell lines. This Special Issue seeks to showcase research papers, short communications, and review articles that focus on: (1) microdevices to mimic or control cellular microenvironment; (2) microdevices to evaluate interactions between different organ models; (3) microdevices to maintain iPS cells or iPSC-derived cells; and (4) sensors and techniques to evaluate drug efficacy or toxicity.

A comprehensive overview of the latest achievements, trends, and the current state of the art of this important and rapidly expanding field. Clearly and logically structured, the first part of the book explores the fundamentals of tissue engineering, providing a separate chapter on each of the basic topics, including biomaterials stem cells, biosensors and bioreactors. The second part then follows a more applied approach, discussing various applications of tissue engineering, such as the replacement or repairing of skins, cartilages, livers and blood vessels, to trachea, lungs and cardiac tissues, to musculoskeletal tissue engineering used for bones and ligaments as well as pancreas, kidney and neural tissue engineering for the brain. The book concludes with a look at future technological advances. An invaluable reading for entrants to the field in biomedical engineering as well as expert researchers and developers in industry.

In this expert handbook both the topics and contributors are selected so as to provide an authoritative view of possible applications for this new technology. The result is an up-to-date survey of current challenges and opportunities in the design and operation of bioreactors for high-value products in the biomedical and chemical industries. Combining theory and practice, the authors explain such leading-edge technologies as single-use bioreactors, bioreactor simulators, and soft sensor monitoring, and discuss novel applications, such as stem cell production, process development, and multi-product reactors, using case studies from academia as well as from industry. A final section addresses the latest trends, including culture media design and systems biotechnology, which are expected to have an increasing impact on bioreactor design. With its focus on cutting-edge technologies and discussions of future developments, this handbook will remain an invaluable reference for many years to come.

The editors of this special volume would first like to thank all authors for their excellent contributions. We would also like to thank Prof. Dr. Thomas Scheper, Dr. Marion Hertel and Ulrike Kreusel for providing the opportunity to compose this volume and Springer for organizational and technical support. Tissue engineering represents one of the major emerging fields in modern b- technology; it combines different subjects ranging from biological and material sciences to engineering and clinical disciplines. The aim of tissue engineering is the development of therapeutic approaches to substitute diseased organs or tissues or improve their function. Therefore, three dimensional biocompatible materials are seeded with cells and cultivated in suitable systems to generate functional tissues. Many different aspects play a role in the formation of 3D tissue structures. In the first place the source of the used cells is of the utmost importance. To prevent tissue rejection or immune response, preferentially autologous cells are now used. In particular, stem cells from different sources are gaining exceptional importance as they can be differentiated into different tissues by using special media and supplements. In the field of biomaterials, numerous scaffold materials already exist but new composites are also being developed based on polymeric, natural or xenogenic sources. Moreover, a very important issue in tissue en- neering is the formation of tissues under well defined, controlled and reprod- ible conditions. Therefore, a substantial number of new bioreactors have been developed.

This book summarizes the NATO Advanced Research Workshop (ARW) on “Nanoengineered Systems for Regenerative Medicine” that was organized under the auspices of the NATO Security through Science Program. I would like to thank NATO for supporting this workshop via a grant to the co-directors. The objective of ARW was to explore the various facets of regenerative me- cine and to highlight role of the “the nano-length scale” and “nano-scale systems” in defining and controlling cell and tissue environments. The development of novel tissue regenerative strategies require the integration of new insights emerging from studies of cell-matrix interactions, cellular signalling processes, developmental and systems biology, into biomaterials design, via a systems approach. The chapters in the book, written by the leading experts in their respective disciplines, cover a wide spectrum of topics ranging from stem cell biology, developmental biology, ce- matrix interactions, and matrix biology to surface science, materials processing and drug delivery. We hope the contents of the book will provoke the readership into developing regenerative medicine paradigms that combine these facets into cli- cally translatable solutions. This NATO meeting would not have been successful without the timely help of Dr. Ulrike Shastri, Sanjeet Rangarajan and Ms. Sabine Benner, who assisted in the organization and implementation of various elements of this meeting. Thanks are also due Dr. Fausto Pedrazzini and Ms. Alison Trapp at NATO HQ (Brussels, Belgium). The commitment and persistence of Ms.

Microscale hydrogels are potentially useful materials for controlling cellular behavior to mimic native microenvironments for tissue engineering applications. In this chapter, various fabrication techniques to generate microscale hydrogels and their applications in tissue engineering have been outlined. In addition, we provide examples of microscale hydrogels with different physical and chemical properties for generation of tissue constructs. Finally, we discuss potential future directions in fabrication of hydrogels to address challenges in tissue engineering. It is expected that these techniques will enable engineering of three-dimensional (3D) structures with controlled features for the formation of functional tissues and organs.