Ischemic heart disease is a major cause of human death worldwide owing to the heart minimal ability to repair following injury. Other than heart transplantation, there are currently no effective or long-lasting therapies for end-stage heart failure. Therefore, it is crucial to develop not only alternative therapies that potentiate heart regeneration or repair, but also new tools to study human cardiac physiology and pathophysiology in vitro. In this context, cardiac tissue engineering arises a promising strategy, as it is aimed at generating cardiac tissue analogues that would act as in vitro models of human cardiac tissue or as surrogates for heart repair. Thus, having 3D human cardiac tissue constructs resembling human myocardium could revolutionize drug discovery and toxicity testing, cardiac disease modelling and regenerative medicine. An strategy to obtain reliable cardiac tissue constructs is to mimic the native cardiac environment. The classical approach is based on seeding cardiomyocytes in biocompatible 3D scaffolds, and then culturing the construct in a biomimetic signaling system, usually a bioreactor. Although major advances have been made, the generation of thick and mature tissue constructs from human induced pluripotent stem cells-derived cardiomyocytes (hiPSC-CM) is still a challenge. Therefore, the hypothesis of our study is that the combination of hiPSC-CM with 3D scaffolds and appropriate regulatory signals may lead to the generation of mature human cardiac tissue constructs resembling human myocardium, both functionally and structurally. To address this, we have characterized a collagen-based 3D scaffold and established an efficient method for cell seeding into the scaffold. We have also developed a parallelized perfusion bioreactor system, which ensures an effective mass transport between cells and culture medium and allows culturing multiple replicas of tissue constructs. In addition, we have designed and fabricated a perfusion chamber including electrodes to electrically stimulate cells during culture, as well as to monitor tissue function. With this advanced 3D culture system, we have been able to generate thick 3D human cardiac constructs with tissue-like functionality. Our results indicate that perfusion of culture medium combined with electrical stimulation and collagen-based scaffold improve the structural and functional maturation of hiPSC-CM. In general terms, electrical stimulation has improved the structural organization, alignment and coupling of cardiomyocytes in our cardiac tissue constructs. Moreover, electrical stimulation has promoted the formation of synchronous contractile constructs at the macroscale with improved electrophysiological functions. Through the development of a new electrophysiological recording system, we report for the first time to our knowledge a technique that provides information about the electrical activity of intact cardiac tissue constructs in real time. Specifically, the combination of action potentials generated by hiPSC-CM composing cardiac constructs produces ECG-like signals, which could be monitored online. Finally, we have demonstrated the ability of stimulated human cardiac tissue constructs to detect drug-induced cardiotoxicity, as typical features of arrhythmias (e.g. prolongation of RR intervals and regular blockades) could be observed upon treatment with sotalol. Taken together, results indicate that macroscopic human cardiac tissue constructs with tissue-like functionality can be obtained through the use of our advanced 3D culture system. We have studied the effects of electrical stimulation on cardiomyocytes at multiple levels: molecular (presence, distribution and expression of cardiac proteins), ultrastructural (sarcomere width and presence of specialized cellular junctions), cellular (morphology and alignment), and functional (amplitude, directionality and strain of contractions, and electrophysiological recordings). Findings validate our in vitro approach as a valuable system to obtain 3D cardiac patches with an improved maturity and functionality. Importantly, the online monitoring system developed in this study can provide essential electrophysiological information of intact cardiac tissue constructs, which opens up myriad possibilities in the field of cardiovascular research.

This book presents a systematic overview of the technologies currently being explored and utilized in the fields of cardiovascular tissue engineering and regenerative medicine. Considering the unprecedented rapid progress occurring on multiple technological fronts in cardiac tissue engineering, this important new volume fills a need for an up-to-date, comprehensive text on emerging advanced biological and engineering tools. The book is an important resource for anyone looking to understand the emerging topics that have the potential to substantially influence the future of the field. Coverage includes iPS stem cell technologies, nanotechnologies and nanomedicine, advanced biomanufacturing, 3D culture systems, 3D organoid systems, genetic approaches to cardiovascular tissue engineering, and organ on a chip. This book will be a valuable guide for research scientists, students, and clinical researchers in the fields of cardiovascular biology, medicine, and bioengineering, as well as industry-based practitioners working in biomaterial science, nanomaterials and technology, and rapid prototyping and biomanufacturing (3D bioprinting).

Regenerative engineering is the convergence of developmental biology, stem cell science and engineering, materials science, and clinical translation to provide tissue patches or constructs for diseased or damaged organs. Various methods have been introduced to create tissue constructs with clinically relevant dimensions. Among such methods, 3D bioprinting provides the versatility, speed and control over location and dimensions of the deposited structures. Three-dimensional bioprinting has leveraged the momentum in printing and tissue engineering technologies and has emerged as a versatile method of fabricating tissue blocks and patches. The flexibility of the system lies in the fact that numerous biomaterials encapsulated with living cells can be printed. This book contains an extensive collection of papers by world-renowned experts in 3D bioprinting. In addition to providing entry-level knowledge about bioprinting, the authors delve into the latest advances in this technology. Furthermore, details are included about the different technologies used in bioprinting. In addition to the equipment for bioprinting, the book also describes the different biomaterials and cells used in these approaches. This text: Presents the principles and applications of bioprinting Discusses bioinks for 3D printing Explores applications of extrusion bioprinting, including past, present, and future challenges Includes discussion on 4D Bioprinting in terms of mechanisms and applications

This Volume of the series Cardiac and Vascular Biology offers a comprehensive and exciting, state-of-the-art work on the current options and potentials of cardiac regeneration and repair. Several techniques and approaches have been developed for heart failure repair: direct injection of cells, programming of scar tissue into functional myocardium, and tissue-engineered heart muscle support. The book introduces the rationale for these different approaches in cell-based heart regeneration and discusses the most important considerations for clinical translation. Expert authors discuss when, why, and how heart muscle can be salvaged. The book represents a valuable resource for stem cell researchers, cardiologists, bioengineers, and biomedical scientists studying cardiac function and regeneration.

This textbook shall introduce the students to 3D cell culture approaches and applications. An overview on existing techniques and equipment is provided and insight into various aspects and challenges that researchers need to consider and face during culture of 3D cells is given. The reader will learn the importance of physiological cell, tissue and organ models and gains important knowledge on 3D analytics. This textbook deepens selected aspects of the textbook “Cell Culture Technology”, which also is published in this series, while offering extended insight into 3D cell culture. The concept of the textbook encompasses various lectures ranging from basics in cell cultivation, tissue engineering, biomaterials and biocompatibility, in vitro test systems and regenerative medicine. The textbook addresses Master- and PhD students interested and/or working in the field of modern cell culture applications and will support the understanding of the essential strategies in 3D cell culture and waken awareness for the potentials and challenges of this application.

This textbook provides an overview on current cell culture techniques, conditions, and applications specifically focusing on human cell culture. This book is based on lectures, seminars and practical courses in stem cells, tissue engineering, regenerative medicine and 3D cell culture held at the University of Natural Resources and Life Sciences Vienna BOKU and the Gottfried Wilhelm Leibniz University Hannover, complemented by contributions from international experts, and therefore delivers in a compact and clear way important theoretical, as well as practical knowledge to advanced graduate students on cell culture techniques and the current status of research. The book is written for Master students and PhD candidates in biotechnology, tissue engineering and biomedicine working with mammalian, and specifically human cells. It will be of interest to doctoral colleges, Master- and PhD programs teaching courses in this area of research.

Cardiac tissue engineering aims at repairing damaged heart muscle and producing human cardiac tissues for application in drug toxicity studies. This book offers a comprehensive overview of the cardiac tissue engineering strategies, including presenting and discussing the various concepts in use, research directions and applications. Essential basic information on the major components in cardiac tissue engineering, namely cell sources and biomaterials, is firstly presented to the readers, followed by a detailed description of their implementation in different strategies, broadly divided to cellular and acellular ones. In cellular approaches, the biomaterials are used to increase cell retention after implantation or as scaffolds when bioengineering the cardiac patch, in vitro. In acellular approaches, the biomaterials are used as ECM replacement for damaged cardiac ECM after MI, or, in combination with growth factors, the biomaterials assume an additional function as a depot for prolonged factor activity for the effective recruitment of repairing cells. The book also presents technological innovations aimed to improve the quality of the cardiac patches, such as bioreactor applications, stimulation patterns and prevascularization. This book could be of interest not only from an educational perspective (i.e. for graduate students), but also for researchers and medical professionals, to offer them fresh views on novel and powerful treatment strategies. We hope that the reader will find a broad spectrum of ideas and possibilities described in this book both interesting and convincing. Table of Contents: Introduction / The Heart: Structure, Cardiovascular Diseases, and Regeneration / Cell Sources for Cardiac Tissue Engineering / Biomaterials: Polymers, Scaffolds, and Basic Design Criteria / Biomaterials as Vehicles for Stem Cell Delivery and Retention in the Infarct / Bioengineering of Cardiac Patches, In Vitro / Perfusion Bioreactors and Stimulation Patterns in Cardiac Tissue Engineering / Vascularization of Cardiac Patches / Acellular Biomaterials for Cardiac Repair / Biomaterial-based Controlled Delivery of Bioactive Molecules for Myocardial Regeneration