ECM components such as laminin, fibronectin and collagen engage the integrin receptors and support to maintain cell identity and function. Organoids rely on artificial extracellular matrices (ECM) to facilitate their self-organization into structures that resemble native tissue. Īlthough still imperfect, organoids represent an attractive model for studying human biology and disease, carrying the potential to answer several unresolved questions. Yet, recent studies are dealing with trying to overcome this limitation through obtaining a tridimensional structure that more closely reproduces the whole cellular diversity of the tissue microenvironment. Failing to recapitulate the complexity of native organs, the (partial) absence of a mesenchymal compartment, vascularization, and microbiome represents therefore a limit of organoid technology. However, although most organoid cultures develop functional tissue units, they lack elements such as mesenchymal, stromal, immune, and neural cells that populate tissue in vivo. Additionally, organoids’ formation recapitulates characteristic processes of self-organization during development. The organoids resemble specific features of organs in vivo: an organoid must indeed contain more than one cell type of the organ it models it should exhibit some function related to that organ and the cells should be organized similarly to the tissue of the organ. The developmental potential of the initiating stem cells influences how complex the organoid can be. Organoids are therefore stem cell-derived and self-organizing 3D cultures that phenocopy cell-type composition, architecture, and, to a certain extent, functionality of different tissues. In the past decade, these prototypical stem cell features have been exploited to develop the organoids in vitro. In general, they can generate all tissues of the developing embryo and maintain tissue homeostasis in adults. Stem cells are present in both embryonic and adult organisms, but they have slightly different properties in each. In multicellular organisms, stem cells are undifferentiated or partially committed cells that can differentiate into various types of cells and proliferate indefinitely to produce more of the same stem cell (the so-called self-renewal). The word “organoid” is mainly used to describe such structure derived from stem cells. The term “organoid” refers to mini clusters of growing cells able to self-organize in vitro and differentiate into functional cell types, resembling an organ 3D structure and function. ![]() Here, we summarize the evolution of biological model systems from the generation of 2D spheroids to 3D organoids by focusing on the generation of cardioids based on the currently available laboratory technologies and outline their high potential for cardiovascular research. Currently, growing cardiac organoid (cardioids) from pluripotent stem cells and cardiac stem/progenitor cells remains an open challenge due to the complexity of the spreading, differentiation, and migration of cardiac muscle and vascular layers. Lineage-specific self-organizing organoids have now been generated for many organs. ![]() ![]() In vitro replication of the cellular micro-environment of a specific tissue leads to reproducing the molecular, biochemical, and biomechanical mechanisms that directly influence cell behavior and fate within that specific tissue. Exploiting the ability of cells to re-aggregate and reconstruct the original architecture of an organ makes it possible to overcome many limitations of 2D cell culture systems. Although 2D cell cultures have been used for more than 50 years, even for their simplicity and low-cost maintenance, recent years have witnessed a steep rise in the availability of organoid model systems. Organoids indeed represent promising systems for the in vitro modeling of tissue morphogenesis and organogenesis, regenerative medicine and tissue engineering, drug therapy testing, toxicology screening, and disease modeling. The growing interest in the use of organoids arises from their ability to mimic the biology and physiology of specific tissue structures in vitro. Organoids are tiny, self-organized, three-dimensional tissue cultures that are derived from the differentiation of stem cells.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |