Cardiac Cell Culture Technologies

Microfluidics is a quite mature technology, but its medical applications for disease diagnosis and personal therapy studies are still insufficient. The usage of the microsystems for such applications should be supported by elaboration of new diagnostic methods/models because the currently applied ones exhibit many drawbacks. An application of the microanalytical devices for this purpose seems to be a promising approach and solution to all mentioned problems, and it can increase the experimental throughput. Organ-on-a-chip systems are used to investigate cell-cell and cell-extracellular matrix (ECM) interactions as well as to perform cytotoxicity assays of various drugs. Lab-on-a-Chip systems for mimicking of organs such as: liver, skin, lung, kidneys, or breast are presented in the literature. The Heart-on-a-chip systems used to simulate the vascular system and heart tissue functions are also fabricated. They play an increasingly important role in biomedical sciences.

Microfluidic technology has a great application potential in many fields of science such as analytical chemistry, molecular biology, or biotechnology. The microfluidic systems are also widely used for cell engineering. The microsystems have several advantages comparing with the traditional analysis, such as: using small volumes of reagents, low power consumption, flexibility, and adaptability to different experimental conditions and purposes. Additionally, in vivo conditions can be better mimicked in the microsystems than in conventional culture methods. In this chapter, the microfluidic systems for cellular application are described. We present important parameters of the microdevices, which have the greatest impact on the cell behavior. The advantages and disadvantages of using the microfluidic systems are also extensively discussed. Furthermore, we characterize some cellular models (static and perfusion; monolayer and spatial) developed in the microsystems. This chapter is an overview of basics of the microfluidic systems for cellular application.

The main advantage of the microsystems is their ability to imitate in vivo conditions which are missing in macroscale cell cultures. The materials which find applications in Lab-on-a-chip devices for cellomics, their properties, and microfabrication techniques are presented in this chapter. Such microfluidic devices are useful tools in many fields involving cell culture studies, e.g., cell trapping, counting or sorting, cell lysis and fusion, cultivation, and drug screening. Construction materials, not only the most commonly used poly(dimethyl siloxane) (PDMS) and glass, but also such polymers as polystyrene (PS), poly(methyl methacrylate) (PMMA), polycarbonate (PC), and cyclic olefin copolymer (COC), are presented. There are many materials which are utilized to create spatial arrangement of the cells in the developed microsystems. For this purpose, natural (e.g., collagen), synthetic (e.g., poly(ethylene glycol)—PEG), and hybrid (e.g., gelatin methacryloyl—GelMA) hydrogels as well as nanofibrous scaffolds are applied. We present short description and some examples of the usage of above materials. This chapter also describes the most common fabrication methods of Lab-on-a-chip (LOC) devices for cellomics. These considerations are extended to potential mass production of cell-based microsystems, using a range of materials. Adopting more time and cost-effective fabrication methods is critical for the integration of LOCs into mainstream applications, and therefore, factors such as quality control or device repeatability were detailed.

Organ-on-a-chip systems are novel platforms, which imitate key functions of living organ, including specific microarchitectures, cell–cell and tissue–tissue interactions, and extracellular communication. Microtechnology offers the possibility of creating more complex, multi-organ platforms known as Body-on-a-chip or Human-on-a-chip. Such integration allows research on inter-tissue and interorgan interactions as well as human metabolism simulation, which plays a key role in studies on toxic and dose-related effects of novel therapies. In this chapter, examples of current developments in Organ-on-a-chip technology are reviewed and discussed.

The heart is one of the most important organs and performs a principal task in the organism providing a blood through the vascular bed. Since cardiovascular diseases (CVD) are known to be a main cause of mortality in humans, there is a huge interest in development of novel therapies for myocardial dysfunction. There is number of proposed approaches; however, a big hope has been placed in stem cell therapies. The best possible candidates among stem cells for cellular therapies of the heart are mesenchymal stem cells (MSC), cardiac cell progenitors (CPC), embryonic stem cells (ESC), and generations of induced pluripotent stem cells (iPSC). iPSCs are potentially helpful, despite their pluripotent induction, low propagation ability, oncogenomic instability, teratoma generation, etc. Adaptation of protocols are further required to improve stem cells resistance to pathological environment, e.g., hypoxic conditions in postinfarcted heart and to enhance their retention. Cooperation between stem cell therapy and gene transfer is presently more often tried in preclinical studies with promising view for prospective clinical trials. Supplementary substances (mostly anti-inflammatory and anti-apoptotic factors) have been considered to maintain stem cell viability which has been examined at in vivo animal models with optimistic results. Combination of all therapies with nanotechnology both for effective stem cell visualization as well as ensuring cell resistance to apoptosis (supported with scaffolds) appear to be necessary for next generation protocols of stem cell interventions. The whole organ (heart) reconstruction attempts have also been described. In this section, we will summarize recent advances in therapy of the heart and methods that could be used to enhance its efficacy in clinical application.

Stem cells are formed during embryonic development and then reside in tissues and organs of adult organism, being responsible for their self-renewal and regeneration. They are also widely used in the studies aiming to understand and also control differentiation of various cell types as well as to design the therapeutic strategies allowing to treat various degenerative diseases and to regenerate damaged tissues and organs. Among the stem cells which attract the most of attention are pluripotent stem cells able to differentiate into any given cell type. These cells could be either derived from preimplantation mammalian embryos or from somatic cells subjected to reprogramming. Multipotent mesenchymal stem cells, on the other hand, are isolated from tissues of adult organisms, such as bone marrow or adipose tissue. Their ability to differentiate is restricted, as compared to pluripotent stem cells. Both types of cells were tested as a source to derive skeletal muscle myoblasts or cardiomyocytes that could be potentially used in clinics. Current review focuses at the characteristics of pluripotent and mesenchymal stem cells and also presents selected studies aiming at their efficient derivation and application in cellular therapies.

The microfluidic systems are designed especially for many biological applications. An Organ-on-a-chip system, used to mimic organ functions, is one type of such microsystems. Various organs, e.g., liver, skin, lung, or breast are investigated in microscale. The microsystems designed for heart cell culture and analysis (called Heart-on-a-chip) are also fabricated. In this chapter, a characterization of the microfluidic systems for cardiac cell culture is described. Interest in this research area stems from the fact that heart diseases are the most common cause of death around the world. Therefore, research issues concerning heart diseases are presented at the beginning of this chapter. Two approaches of investigating cardiac cells in microscale are shown: the creation of a beating heart culture model, which mimics heart tissue and the creation of a whole vascular system, which mimics blood flow in vessels. Specific properties, which have to be provided in Heart-on-a-chip systems, are also presented. Features such as: perfusion conditions, electrical field, stretching, hydrogels, and nanofibres are used to mimic a native myocardium. Additionally, heart cell culture in the microsystems is often used to simulate heart diseases and investigate heart regeneration using stem cells (SCs).

Heart diseases are the most common cause of death around the world. Therefore, it is important to develop new drugs and therapies, which can be useful in the treatment of cardiovascular diseases (CVDs). Elaboration of in vivo-like culture models of heart cells will allow the mimicking of native heart tissue and the investigation of heart cell response to the exposure of external stimuli. Heart-on-a-chip systems can be successfully used to imitate heart tissue functions and to perform assays based on cardiotherapy. In this chapter, we present Heart-on-a-chip systems, which can be utilized for various types of assays. Different cardiac cell cultures performed in Lab-on-a-chip systems are characterized at the beginning of this chapter. Single, monolayer, and spatial cell cultures are presented. Next, examples of cardiotoxicity assays and electrical stimulations performed in Heart-on-a-chip systems are described. Methods of heart cell analysis used in microscale are also defined. Finally, we summarize the research focused on Heart-on-a-chip systems and we outline perspectives for the usage of such microsystems.

Stem cells (SCs) are the main source of biological material used in cell therapy and tissue engineering. Additionally, these cells are being investigated as a potential therapy technique for cardiovascular diseases (CVDs) and heart regeneration. To improve the investigation of SC proliferation and maturation, the Lab-on-a-Chip systems are being developed. There are many reports, which have proven that such microsystems have been successfully used for SC differentiation into different cell lineages. In this chapter, we present Heart-on-a-chip systems based on stem cells—the microsystems utilized for SC differentiation into cardiomyocytes (CMs). Various types of SC differentiation performed in Lab-on-a-chip systems are presented at the beginning of this chapter. Next, biochemical, physical and mechanical stimulations are presented as techniques to perform cardiogenesis. Other promising methods, especially the use of graphene and their other forms, which could be used for cardiac differentiation, are presented at the end of this chapter. Finally, we summarize the research focused on heart regeneration using the Lab-on-a-chip systems, and we outline future perspectives for microsystem usage for SC differentiation into CMs.