Droplet microfluidics technology offers refined control over the flows of multiple fluids in micro/nano-scale, enabling fabrication of micro/nano-droplets with precisely adjustable structures and compositions in a high-throughput manner. With the combination of proper hydrogel materials and preparation methods, single or multiple cells can be efficiently encapsulated into hydrogels to produce cell-loaded hydrogel microspheres. The cell-loaded hydrogel microspheres can provide a three-dimensional, relatively independent and controllable microenvironment for cell proliferation and differentiation, which is of great value for three-dimensional cell culture, tissue engineering and regenerative medicine, stem cell research, single cell study and many other biological science fields. In this review, the preparation methods of cell-loaded hydrogel microspheres based on droplet microfluidics and its applications in biomedical field are summarized and future prospects are proposed.
Hydrogels/chemistry* ; Microfluidics/methods* ; Microspheres ; Regenerative Medicine ; Tissue Engineering/methods*

From the perspective of Regenerative Medicine, the tissue generated in vitro can imitate the physiological and pathological tissue to a certain extent. However, the structures and functions of the in vitro tissue are very simple so that research on in vitro self-assembling and imitating of tissue development is necessary. The development of Nanotechnology and the technology of micro-structure makes the in vitro tissue assembling possible. As previous studies showed that, besides genetic material, tissue architecture and its micro-environment are closely related to morphogenesis of in vitro tissue. Thus, how to design and assemble microstructure to make the tissue molding still requires effort. How to predict and control the development mechanism in vitro is also a question needed to be resolved. In this essay, we reviewed the mechanism of assembling and imitating of in vitro tissue based on the theory of physics, biology and systemic integrated structure.
Animals ; Computer Simulation ; Humans ; Microtechnology ; methods ; Nanostructures ; chemistry ; Regenerative Medicine ; methods ; Tissue Engineering ; methods

This article introduces the basic theories about atomic force microscope (AFM) and electron microscope (EM), respectively. New applications of each microscopic technology in regenerative medicine, covering both material science and life science, are discussed. The advantages or disadvantages of the kinds of microscopes in working conditions, sample preparation, resolution and the like, are discussed and compared systematically to make clear each scope of applications. This could be a useful guide for selecting the appropriate microscopic analysis in research work about regenerative medicine.
Humans ; Microscopy, Atomic Force ; methods ; trends ; Microscopy, Electron ; methods ; trends ; Regenerative Medicine ; methods ; trends

OBJECTIVETo give a concise review of the current state of the art in tissue engineering (TE) related to skeletal muscle and kinds of bioreactor environment.

DATA SOURCESThe review was based on data obtained from the published articles and guidelines.

STUDY SELECTIONA total of 106 articles were selected from several hundred original articles or reviews. The content of selected articles is in accordance with our purpose and the authors are authorized scientists in the study of engineered muscle tissue in bioreactor.

RESULTSSkeletal muscle TE is a promising interdisciplinary field which aims at the reconstruction of skeletal muscle loss. Although numerous studies have indicated that engineering skeletal muscle tissue may be of great importance in medicine in the near future, this technique still represents a limited degree of success. Since tissue-engineered muscle constructs require an adequate connection to the vascular system for efficient transport of oxygen, carbon dioxide, nutrients and waste products. Moreover, functional and clinically applicable muscle constructs depend on adequate neuromuscular junctions with neural cells. Third, in order to engineer muscle tissue successfully, it may be beneficial to mimic the in vivo environment of muscle through association with adequate stimuli from bioreactors.

CONCLUSIONVascular system and bioreactors are necessary for development and maintenance of engineered muscle in order to provide circulation within the construct.

Animals ; Cell Culture Techniques ; Humans ; Lung ; cytology ; Regenerative Medicine ; methods ; Stem Cell Transplantation ; methods

In the field of plastic and reconstructive surgery, the loss of organs or tissues caused by diseases or injuries has resulted in challenges, such as donor shortage and immunosuppression. In recent years, with the development of regenerative medicine, the decellularization-recellularization strategy seems to be a promising and attractive method to resolve these difficulties. The decellularized extracellular matrix contains no cells and genetic materials, while retaining the complex ultrastructure, and it can be used as a scaffold for cell seeding and subsequent transplantation, thereby promoting the regeneration of diseased or damaged tissues and organs. This review provided an overview of decellularization-recellularization technique, and mainly concentrated on the application of decellularization-recellularization technique in the field of plastic and reconstructive surgery, including the remodeling of skin, nose, ears, face, and limbs. Finally, we proposed the challenges in and the direction of future development of decellularization-recellularization technique in plastic surgery.
Tissue Engineering/methods* ; Tissue Scaffolds/chemistry* ; Surgery, Plastic ; Regenerative Medicine/methods* ; Extracellular Matrix

The need for organ and tissue regeneration in patients continues to increase because of a scarcity of donors, as well as biocompatibility issues in transplant immune rejection. To address this, scientists have investigated artificial tissues as an alternative to transplantation. Three-dimensional (3D) bioprinting technology is an additive manufacturing method that can be used for the fabrication of 3D functional tissues or organs. This technology promises to replicate the complex architecture of structures in natural tissue. To date, 3D bioprinting strategies have confirmed their potential practice in regenerative medicine to fabricate the transplantable hard tissues, including cartilage and bone. However, 3D bioprinting approaches still have unsolved challenges to realize 3D hard tissues. In this manuscript, the current technical development, challenges, and future prospects of 3D bioprinting for engineering hard tissues are reviewed.
Bioprinting* ; Cartilage ; Humans ; Methods ; Regeneration ; Regenerative Medicine ; Tissue Donors ; Tissue Engineering*

ObjectiveSince the advent of induced pluripotent stem cell (iPSC) technology a decade ago, enormous progress has been made in stem cell biology and regenerative medicine. Human iPSCs have been widely used for disease modeling, drug discovery, and cell therapy development. In this review, we discuss the progress in applications of iPSC technology that are particularly relevant to drug discovery and regenerative medicine, and consider the remaining challenges and the emerging opportunities in the field.

Data SourcesArticles in this review were searched from PubMed database from January 2014 to December 2017.

Study SelectionOriginal articles about iPSCs and cardiovascular diseases were included and analyzed.

ResultsiPSC holds great promises for human disease modeling, drug discovery, and stem cell-based therapy, and this potential is only beginning to be realized. However, several important issues remain to be addressed.

ConclusionsThe recent availability of human cardiomyocytes derived from iPSCs opens new opportunities to build in vitro models of cardiac disease, screening for new drugs and patient-specific cardiac therapy.

Cell/gene-activated biomaterials are the main tendency and characteristics of the biomaterial researches for the future. The gene delivery based on the polymeric materials as vectors has potential applications in gene therapy, regenerative medicine and tissue engineering. In this paper, the application of layer-by-layer (LBL) technique in advanced biomaterial surface engineering is reviewed and its potential application in the construction of in situ gene delivery system onto biomaterial surface is in turn addressed. These are of great significance to biomaterial researches.
Biocompatible Materials ; chemistry ; DNA ; metabolism ; pharmacokinetics ; Regenerative Medicine ; methods ; Surface Properties ; Tissue Engineering ; methods ; trends ; Tissue Scaffolds ; Transfection

Recent advances have shown the direct reprogramming of mouse and human fibroblasts into induced neural stem cells (iNSCs) without passing through an intermediate pluripotent state. Thus, direct reprogramming strategy possibly provides a safe and homogeneous cellular platform. However, the applications of iNSCs for regenerative medicine are limited by the restricted availability of cell sources. Human umbilical cord blood (hUCB) cells hold great potential in that immunotyped hUCB units can be immediately obtained from public banks. Moreover, hUCB samples do not require invasive procedures during collection or an extensive culture period prior to reprogramming. We recently reported that somatic cells can be directly converted into iNSCs with high efficiency and a short turnaround time. Here, we describe the detailed method for the generation of iNSCs derived from hUCB (hUCB iNSCs) using the lineage-specific transcription factors SOX2 and HMGA2. The protocol for deriving iNSC-like colonies takes 1~2 weeks and establishment of homogenous hUCB iNSCs takes additional 2 weeks. Established hUCB iNSCs are clonally expandable and multipotent producing neurons and glia. Our study provides an accessible method for generating hUCB iNSCs, contributing development of in vitro neuropathological model systems.
Animals ; Fetal Blood* ; Fibroblasts ; Humans* ; In Vitro Techniques ; Methods ; Mice ; Neural Stem Cells* ; Neuroglia ; Neurons ; Regenerative Medicine ; Transcription Factors ; Umbilical Cord*