The frequency of extramedullary infiltration (EMI) in acute myeloblastic leukemia (AML) is reported up to 40% and most prevalent in myelo-monoblastic and monoblastic subtypes of AML (M4 and M5 according to FAB classification). The majority of patients with EMI suffered poor prognosis. To explore mechanism underlying EMI, we analyzed SHI-1 ...

Hydrogels are synthetic or natural polymer networks that closely mimic native extracellular matrices. As hydrogel-based vehicles are being increasingly employed in therapeutic cell delivery, two inherent traits of most common hydrogels, namely low cell affinity and high cell constraint, have significantly drawn the attention of biomedical community. These two properties ...

Collagen is highly conserved across species and has been used extensively for tissue regeneration; however, its mechanical properties are limited. A recent advance using plastic compression of collagen gels to achieve much higher concentrations significantly increases its mechanical properties at the neo-tissue level. This controlled, cell-independent process allows the engineering ...

Biodegradable nanofibers simulate the fibril structure of natural extracellular matrix, and provide a cell-friendly microenvironment for tissue regeneration. However, the effects of nanofiber organization and immobilized biochemical factors on cell infiltration into three-dimensional scaffolds are not well understood. For example, cell infiltration into an electrospun nanofibrous matrix is often limited ...

In our previous work, biomimetic calcium phosphate-coated poly(caprolactone) nanofibre meshes (BCP-NMs) were demonstrated to be more effective for supporting cell attachment and proliferation under static conditions, when compared with poly(caprolactone) nanofibre meshes (PCL-NMs). In many applications, in vitro cultivation of constructs using bioreactors that support efficient nutrition of cells has ...

The ability to bioengineer three-dimensional (3D) tissues is a potentially powerful approach to treat diverse diseases such as cancer, loss of tissue function, or organ failure. Traditional tissue engineering methods, however, face challenges in fabricating 3D tissue constructs that resemble the native tissue microvasculature and microarchitectures. We have developed a ...

Three-dimensional collagen gel contraction is the standard assay utilized for functionally quantifying a variety of cell types, in particular smooth muscle cells (SMCs) and myofibroblasts. Here, we have developed a method to effectively reduce the three-dimensional parameters of the standard collagen gel into a single, linear measurement. Cell/collagen suspensions that ...

Cellular organization within a multicellular organism requires that a cell assess its relative location, taking in multiple cues from its microenvironment. Given that the extracellular matrix (ECM) consists of the most abundant proteins in animals and contributes both structure and elasticity to tissues, ECM probably provides key physical cues to ...

Experimental studies in animals and recent human clinical trials have revealed the current limitations of cellular transplantation, which include poor cell survival, lack of cell engraftment, and poor differentiation. Evidence in animals suggests that use of a 3-dimensional scaffold may enhance cell therapy and engineer myocardial tissue by improving initial ...

The periodontal ligament (PDL), a connective tissue located between the cementum of teeth and the alveolar bone of mandibula, plays a crucial role in the maintenance and regeneration of periodontal tissues. The PDL contains fibroblastic cells of a heterogeneous cell population, from which we have established several cell lines previously. ...

OBJECTIVE: To explore tissue organization based on the geometry of cell neighborhoods in histologic preparations. STUDY DESIGN: Local complexity of solid tissues was measured in images of discrete tissue compartments. Exclusive areas associated with cell nuclei (v-cells) were computed using a watershed transform of the nuclear staining intensity. Mathematical morphology ...

AIM: To investigate the possibility of chondrogenic differentiation and cartilage repair of synovial fluid cells of osteoarthritis (OA) knee. METHODS: Synovial fluids from 26 patients with OA knee were aspirated from each knee joint and cultured in vitro. The morphology of cultured synovial fluid cells, cell proliferation rate, the phenotype, ...

Mechanical signal is important for regulating cellular activities, including proliferation, metabolism, matrix production, and orientation. Bioreactors with loading functions can be used to precondition cells in three-dimensional (3D) constructs so as to study the cellular responses to mechanical stimulation. However, full-scale bioreactor is not always an affordable option considering the ...

Carbohydrates are integral components of the stem cell niche on several levels; proteoglycans are a major constituent of the extracellular matrix (ECM) surrounding a cell, glycosoaminoglycans (GAGs) help link cells to the ECM and the neighboring cells, and small but informationally-rich oligosaccharides provide a "sugar code" that identifies each cell ...

Adult stem cells, or mesenchymal stromal cells (MSCs), are of great potential for cell therapy and tissue-engineering applications. However, for therapeutic use, these cells need to be isolated from tissue or a biopsy and efficiently expanded, as they cannot be harvested in sufficient quantities from the body. In our opinion, ...

The aim of this study was to investigate the interconnection between the processes of proliferation, dedifferentiation, and intrinsic redifferentiation (chondrogenic) capacities of human articular chondrocyte (HAC), and to identify markers linking HAC dedifferentiation status with their chondrogenic potential. Cumulative population doublings (PD) of HAC expanded in monolayer culture were determined, ...

We elucidated the localization of Thy-1-positive cells in the perichondrium of fetal rat limb bones to clarify the distribution of osteogenic cells in the process of endochondral ossification. We also examined the formation of calcified bone-like matrices by isolated perichondrial cells in vitro. At embryonic day (E) 15.5, when the ...

Cartilage tissue engineering, in which chondrogenic cells are combined with a scaffold, is a cell-based approach to regenerate damaged cartilage. Various scaffold materials have been investigated, among which are hydrogels. Previously, we have developed dextran-based hydrogels that form under physiological conditions via a Michael-type addition reaction. Hydrogels can be formed ...

Direct intra-articular injection of mesenchymal stem cells (MSCs) has been proposed as a potential cell therapy for cartilage defects. This cell therapy relies on the survival of the implanted MSCs. However, the arduous local environment may limit cell viability after implantation, which would restrict the cells' regenerative capacity. Thus, it ...

The following in vitro translational study investigated whether enamel matrix derivative (EMD), an approved biomimetic treatment for periodontal disease (Emdogain) and hard-to-heal wounds (Xelma), enhanced synovial cell colonization and protein synthesis around a scaffold used clinically for in situ tissue engineering of the torn anterior cruciate ligament (ACL). Synovial cells ...

Cell-based therapy for myocardial infarction (MI) holds great promise; however, the ideal cell type and delivery system have not been established. Obstacles in the field are the massive cell death after direct injection and the small percentage of surviving cells differentiating into cardiomyocytes. To overcome these challenges we designed a ...

The central role of the adipose tissue in lipid metabolism places specific demands on the cell structure of adipocytes. The protein composition and dynamics of the extracellular matrix (ECM) is of crucial importance for the functioning of those cells. Adipogenesis is a bi-phasic process in which the ECM develops from ...

Tumor cells can migrate in 3D matrices in either a mesenchymal-like or amoeboid mode. HT1080 fibrosarcoma cells cultured in 3D collagen gels change their morphology from mesenchymal-like (elongated) to amoeboid (round) following protease inhibitor (PI) treatment or active Rho or ROCK expression. In this study, we examined the role of ...

Tissue-engineered constructs can be fabricated by the assembly of smaller building blocks in order to mimic much of the native biology that is often made from repeating functional units. Our aim was to realize a three-dimensional (3-D) tissue-like construct in vitro by inducing the assembly of functional micrometric tissue precursors ...

One of the major challenges in scaffold guided regenerative therapies is identifying the essential cues such as mechanical forces that induce cellular responses to form functional tissue. Developing multi-scale modelling methods would facilitate in predicting responses of encapsulated cells for controlling and maintaining the cell phenotype in an engineered tissue ...

Our research is focused on the design of hydrogel biomaterials that can be used for 3-D cell encapsulation and tissue engineering. In this study, our goal was to engineer a temperature-responsive biomaterial to possess bioactive properties using polymer and protein chemistry, and at the same time provide the biomaterial with ...

The effect of scaffold shape on dentin regeneration is not well understood. In this study, porous hydroxyapatite/beta-tricalcium phosphate (HAp/beta-TCP), powdered HAp/beta-TCP, and polyglycolic acid (PGA) fiber mesh were used as scaffolds and transplanted with cultured porcine dental pulp-derived cells into the backs of nude mice. Samples were harvested after 6 ...

We demonstrate that Dz13, a DNA enzyme that cleaves c-Jun mRNA, and is capable of inhibiting cancer cell growth in vitro, can be encapsulated into chitosan nanoparticles. For optimisation of this chitosan-based formulation, pH 6, 0.02% chitosan concentration, and 55 degrees C were found to be best among the variables ...

A combination of high-throughput material formulation and microarray techniques were synergistically applied for the efficient analysis of the biological functionality of 135 binary polymer blends. This allowed the identification of cell-compatible biopolymers permissive for human skeletal stem cell growth in both in vitro and in vivo applications. The blended polymeric ...

Artificial tissue growth requires cells to proliferate and differentiate within the host scaffold. As cell function is governed by mechano-sensitive selection, tissue type is influenced by the microscopic forces exposed to the cells, which is a product of macroscopically straining the scaffold. Accordingly, the microscopic strain environment within a CG ...

Guided assembly of microscale tissue subunits (i.e. 3D cell clusters/aggregates) has found applications in cell therapy/tissue engineering, cell and developmental biology, and drug discovery. As cluster size and geometry are known to influence cellular responses, the ability to spatially control cluster formation in a high throughput manner could be advantageous ...

The biomechanical behaviour of biological cells is of great importance in many physiological processes. One such process is the maintenance of fibrous networks, such as collagenous tissues. The activity of the fibre-producing cells in this type of tissue is very important, and a comprehensive material description needs to incorporate the ...

Understanding the influence of a controlled spatial distribution of biological cues on cell activities can be useful to design "cell instructive" materials, able to control and guide the formation of engineered tissues in vivo and in vitro. To this purpose, biochemical and mechanical properties of the resulting biomaterial must be ...

For repairing cartilage defects by cartilage tissue engineering, it is important that engineered cartilage that is fabricated with scaffolds and cells can maintain the biological and physiological functions of cartilage, and also can induce three-dimensional spatial organization of chondrocytes. In this sense, hydrogels such as fibrin gels (FG) and hyaluronan ...

Myofibroblasts are a differentiated cell type essential for wound healing, participating in tissue remodeling following insult. Myofibroblasts are typically activated fibroblasts, although they can also be derived from other cell types, including epithelial cells, endothelial cells, and mononuclear cells. In most organ systems, cell signals initiated following tissue-specific insult or ...

Epithelial-mesenchymal interactions play a key role in the development of tissues such as tooth, lungs, and kidneys. To successfully engineer or repair such living tissues it is necessary to first understand the complex cell-cell and cell-matrix interactions underlying organogenesis. To mimic an in vivo setting it is necessary to assemble ...

Tissue engineering holds great promise as an alternative strategy to current treatment modalities of diseased or otherwise failed tissues. Most strategies of tissue engineering rely on three-dimensional porous scaffolds to mimic the natural extracellular matrix (ECM) as templates onto which cells attach, multiply, migrate and function. When cells are harvested ...

A major question in biomimetic tissue engineering is how much of the structure/function of native vasculature needs to be reproduced for effective tissue perfusion. O2 supplied to cells in 3D scaffolds in vitro is initially dependent upon diffusion through the scaffold and cell consumption. Low O2 (3%) enhances specific cell ...

Transplantation of olfactory ensheathing cells (OECs) is a potential treatment for spinal cord injury (SCI). However, this process lacks extracellular matrix guiding cell growth, tissue morphogenesis, and remodeling. In order to solve this problem, we fabricated silk fibroin scaffolds (SFS) with different fiber diameters by electrospinning. The behaviors of OECs ...

Most current methods for cell monitoring on 3D porous scaffolds involve end-stage investigation of scaffolds. Repeated measurements on scaffolds, without disturbing cell vitality and proliferation, are needed to relate in vitro to in vivo data. Alamar Blue was used for this purpose. Two different Ca/P scaffolds were studied, using rat ...

Cardiac and skeletal muscle tissue engineering provides a smart approach to overcome problems associated with organ transplantation and cardiac tissue and also lays a platform for superior alternative approaches in muscle regeneration. The aim of the study was to demonstrate cryogel scaffold potential in the field of skeletal muscle and ...

Neuromyelitis optica spectrum disorders (NMOSD) are severe central nervous system inflammatory demyelinating disorders (CNS IDD) characterized by monophasic or relapsing, longitudinally extensive transverse myelitis (LETM) and/or optic neuritis (ON). A significant proportion of NMOSD patients are seropositive for aquaporin-4 (AQP4) autoantibodies. We compared the AQP4 autoantibody detection rates of tissue-based ...

BACKGROUND: The interfacial molecular mechanisms that regulate mammalian cell growth and differentiation have important implications for biotechnology (production of cells and cell products) and medicine (tissue engineering, prosthetic implants, cancer and developmental biology). We demonstrate here that engineered protein motifs can be robustly displayed to mammalian cells in vitro in ...

Cell cooperation is a critical event during tissue development. We present the first precise metrics to quantify the interaction between mesenchymal stem cells (MSCs) and extra cellular matrix (ECM). In particular, we describe cooperative collagen alignment process with respect to the spatio-temporal organization and function of mesenchymal stem cells in ...

The purpose of this investigation was to evaluate the effects of Duabanga grandiflora (Sonneratiaceae), which has been used as a traditional Thai medicine on human skin cells. The leaf extract of D. grandiflora actively affected several human skin cells such as skin whitening, anti-aging and anti-inflammation. It became evident that ...

The present study shows that alumina nanotopography affects monocyte/macrophage behavior. Human mononuclear cells cultured on alumina membranes with pore diameters of 20 and 200 nm were evaluated in terms of cell adhesion, viability, morphology, and release of proinflammatory cytokines. After 24 hours, cell adhesion was assessed by means of light microscopy ...

Fibroadenomas are human benign breast tumors characterized by proliferation of epithelial and stroma cells of the terminal ductal unit. Expression of O-glycans seems to contribute to the proliferation and transformation events. With this in mind, we evaluated the expression of glycans in fibroadenoma tissue through immunohistochemistry with antibodies against mucin ...

ABSTRACT: 3D-scaffolds have been shown to direct cell growth and differentiation in many different cell types, with the formation and functionalisation of the 3D-microenviroment being important in determining the fate of the embedded cells. Here we used a hydrogel-based scaffold to investigate the influences of matrix concentration and functionalisation with ...

Electrospinning was used to fabricate fibrous scaffolds of lipase-catalyzed poly(omega-pentadecalactone) (PPDL). The slow resorbability of this biomaterial is expected to be valuable for tissue-engineering applications requiring long healing times. The effect of solvent systems and instrumental parameters on fiber morphology was investigated. PPDL electrospinning was optimized and defect-free fibers (diameter ...

Regenerative medicine encompasses "tissue engineering" - the in vitro fabrication of tissues and/or organs using scaffold material and viable cells - and "cell therapy" - the transplantation or manipulation of cells in diseased tissue in vivo. In the cardiovascular system, tissue engineering strategies are being pursued for the development of ...