Embedded 3D printing in self-healing annealable composites for functional patterning of human neural constructs

Human in vitro models of neural tissue with controllable cellular composition, tunable microenvironment, and defined spatial patterning are needed to facilitate studies of brain development and disease. Towards this end, bioprinting has emerged as a promising strategy. However, precise and programmable printing of extremely soft and compliant materials that are permissive for stem cell differentiation and functional neuronal growth has been a major challenge. Therefore, solutions for engineering structurally and functionally defined human neural constructs remain scarce. Here, we present a modular platform for bioengineering of neuronal networks via direct embedded 3D printing of human stem cells inside Self-Healing Annealable Particle-Extracellular matrix (SHAPE) composites. The approach combines rheological benefits of granular soft microgel supports with the versatile biomimicry of bulk hydrogels to simultaneously enable precise freeform patterning of stem cells, and consequent generation and long-term maintenance of subtype-specific neurons within engineered networks that extend into the bulk of the annealed support. The developed approach further allows multi-ink deposition, live spatial and temporal monitoring of oxygen levels, as well as creation of vascular channels. Due to its modularity, SHAPE biomanufacturing toolbox not only offers a solution for functional modeling of mechanically sensitive neural constructs, but also has potential to be applied to a wide range of biomaterials with different crosslinking mechanisms to model tissues and diseases where recapitulation of complex architectural features and topological cues is essential.

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Lysosomal Glycohydrolase Activities in Dendritic Cells: Is It a Function of Hematopoietic Stem Cells Differentiation Process?.

Blood ◽

10.1182/blood.v104.11.4193.4193 ◽

2004 ◽

Vol 104 (11) ◽

pp. 4193-4193

Author(s):

Anna C. Berardi ◽

Pamela Manieri ◽

Elisa Ciraci ◽

Roberto Tribuzi ◽

Ilaria Di Girolamo ◽

...

Keyword(s):

Stem Cells ◽

Dendritic Cells ◽

Hematopoietic Stem Cells ◽

Cellular Proliferation ◽

Stem Cell Differentiation ◽

Neoplastic Disease ◽

Differentiation Process ◽

Hematopoietic Stem ◽

Wide Range

Abstract A key mechanism responsible for processing of peptide-MHC class II complexes in mature Dendritic Cells (DCs) is the generalized activation of lysosomal function. Mechanisms underlie these developmental changes are controversial. Thus, it is unclear whether immature DCs can present self antigens, and which are the checkpoints that regulate antigen presentation in immature and mature DCs. Here we generated in-vitro human DCs from peripheral blood CD34+ hematopoietic stem cells (HSCs), by adding to the medium culture Flt-3, GM-CSF, IL-4, and TNF-a (cytokine cocktail, CC) at 37°C for 14 days, and analysed the lysosomal glycohydrolases production and function. Lysosomal enzymes, b-N-Acetyl-Hexosaminidase, a-Mannosidase, b-Galactosidase and b-Glucoronidase are highly increased in a wide range in DCs (14 days of culture) with respect to the CD34+HSCs. All the glycohydrolases activities measured at 3 and 7 days in-vitro culture, were similar and four times more than CD34+HSCs (day 0) respectively. Interestingly, no activities increase were observed, even when SCF, an early acting cytokine, promoting cellular proliferation, were added to the CC medium, indicating that this phenomenon is independent from the proliferation process. Moreover, LPS treatment, to induce DCs maturation, slightly enhance the specific activities of all enzymes that we tested as respect to the untreated cells. and support the evidence that the lysosomal glycohydrolases activation is up-stream to DCs maturation process. Furthermore, for the first time, this date indicated that lysosomal glycohydrolases are regulated during the stem cell differentiation process. Understanding the key mechanism leading this phenomenon is critical for therapeutic application in immunologic or neoplastic disease.

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Insights into Differentiation of Melanocytes from Human Stem Cells and Their Relevance for Melanoma Treatment

Cancers ◽

10.3390/cancers12092508 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2508

Author(s):

Madalina Mirea ◽

Stefan Eckensperger ◽

Markus Hengstschläger ◽

Mario Mikula

Keyword(s):

Stem Cells ◽

Cell Differentiation ◽

Developmental Process ◽

Epithelial Mesenchymal Transition ◽

Stem Cell Differentiation ◽

Human Stem Cells ◽

Mesenchymal Transition ◽

Melanocytic Differentiation

Malignant melanoma represents a highly aggressive form of skin cancer. The metastatic process itself is mostly governed by the so-called epithelial mesenchymal transition (EMT), which confers cancer cells migrative, invasive and resistance abilities. Since EMT represents a conserved developmental process, it is worthwhile further examining the nature of early developmental steps fundamental for melanocyte differentiation. This can be done either in vivo by analyzing the physiologic embryo development in different species or by in vitro studies of melanocytic differentiation originating from embryonic human stem cells. Most importantly, external cues drive progenitor cell differentiation, which can be divided in stages favoring neural crest specification or melanocytic differentiation and proliferation. In this review, we describe ectopic factors which drive human pluripotent stem cell differentiation to melanocytes in 2D, as well as in organoid models. Furthermore, we compare developmental mechanisms with processes described to occur during melanoma development. Finally, we suggest differentiation factors as potential co-treatment options for metastatic melanoma patients.

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Stem Cells as In Vitro Models of Disease

Current Stem Cell Research & Therapy ◽

10.2174/157488807782793772 ◽

2007 ◽

Vol 2 (4) ◽

pp. 280-292 ◽

Cited By ~ 4

Author(s):

Pilar Ruiz-Lozano ◽

Prithi Rajan

Keyword(s):

Stem Cells ◽

In Vitro Models ◽

Models Of Disease

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Dental Pulp-Derived Mesenchymal Stem Cells for Modeling Genetic Disorders

International Journal of Molecular Sciences ◽

10.3390/ijms22052269 ◽

2021 ◽

Vol 22 (5) ◽

pp. 2269

Author(s):

Keiji Masuda ◽

Xu Han ◽

Hiroki Kato ◽

Hiroshi Sato ◽

Yu Zhang ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Dental Pulp ◽

Genetic Disorders ◽

In Vitro Models ◽

High Plasticity ◽

Human Teeth ◽

Clinical Diagnoses ◽

Models Of Disease

A subpopulation of mesenchymal stem cells, developmentally derived from multipotent neural crest cells that form multiple facial tissues, resides within the dental pulp of human teeth. These stem cells show high proliferative capacity in vitro and are multipotent, including adipogenic, myogenic, osteogenic, chondrogenic, and neurogenic potential. Teeth containing viable cells are harvested via minimally invasive procedures, based on various clinical diagnoses, but then usually discarded as medical waste, indicating the relatively low ethical considerations to reuse these cells for medical applications. Previous studies have demonstrated that stem cells derived from healthy subjects are an excellent source for cell-based medicine, tissue regeneration, and bioengineering. Furthermore, stem cells donated by patients affected by genetic disorders can serve as in vitro models of disease-specific genetic variants, indicating additional applications of these stem cells with high plasticity. This review discusses the benefits, limitations, and perspectives of patient-derived dental pulp stem cells as alternatives that may complement other excellent, yet incomplete stem cell models, such as induced pluripotent stem cells, together with our recent data.

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Construction of a mammalian embryo model from stem cells organized by a morphogen signalling centre

Nature Communications ◽

10.1038/s41467-021-23653-4 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Peng-Fei Xu ◽

Ricardo Moraes Borges ◽

Jonathan Fillatre ◽

Maraysa de Oliveira-Melo ◽

Tao Cheng ◽

...

Keyword(s):

Stem Cells ◽

Cell Tracking ◽

Cardiac Tissue ◽

Embryonic Stem ◽

Mammalian Embryo ◽

Wide Range ◽

Vitro Model ◽

Neurula Stage

AbstractGenerating properly differentiated embryonic structures in vitro from pluripotent stem cells remains a challenge. Here we show that instruction of aggregates of mouse embryonic stem cells with an experimentally engineered morphogen signalling centre, that functions as an organizer, results in the development of embryo-like entities (embryoids). In situ hybridization, immunolabelling, cell tracking and transcriptomic analyses show that these embryoids form the three germ layers through a gastrulation process and that they exhibit a wide range of developmental structures, highly similar to neurula-stage mouse embryos. Embryoids are organized around an axial chordamesoderm, with a dorsal neural plate that displays histological properties similar to the murine embryo neuroepithelium and that folds into a neural tube patterned antero-posteriorly from the posterior midbrain to the tip of the tail. Lateral to the chordamesoderm, embryoids display somitic and intermediate mesoderm, with beating cardiac tissue anteriorly and formation of a vasculature network. Ventrally, embryoids differentiate a primitive gut tube, which is patterned both antero-posteriorly and dorso-ventrally. Altogether, embryoids provide an in vitro model of mammalian embryo that displays extensive development of germ layer derivatives and that promises to be a powerful tool for in vitro studies and disease modelling.

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Biomaterials Nano Geometry for Control of Stem Cell Differentiation

MRS Proceedings ◽

10.1557/proc-1239-vv02-02 ◽

2009 ◽

Vol 1239 ◽

Author(s):

Karla Brammer ◽

Seunghan Oh ◽

Sungho Jin

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Mesenchymal Stem Cell ◽

Stem Cell Differentiation ◽

Human Mesenchymal Stem Cell ◽

Oxide Surface ◽

Specific Cell ◽

Implant Surface ◽

Multipotent Stem Cells

AbstractTwo important goals in stem cell research are to control the cell proliferation without differentiation, and also to direct the differentiation into a specific cell lineage when desired. Recent studies indicate that the nanostructures substantially influence the stem cell behavior. It is well known that mesenchymal stem cells (MSCs) are multipotent stem cells that can differentiate into stromal lineages such as adipocyte, chondrocyte, fibroblast, myocyte, and osteoblast cell types. By examining the cellular behavior of MSCs cultured in vitro on nanostructures, some understanding of the effects that the nanostructures have on the stem cell’s response has been obtained. Here we demonstrate that TiO2 nanotubes produced by anodization on Ti implant surface can regulate human mesenchymal stem cell (hMSC) differentiation towards an osteoblast lineage in the absence of osteogenic inducing factors. Altering the dimensions of nanotubular-shaped titanium oxide surface structures independently allowed either augmented human mesenchymal stem cell (hMSC) adhesion at smaller diameter levels or a specific differentiation of hMSCs into osteoblasts using only the geometric cues. Small (˜30 nm diameter) nanotubes promoted adhesion without noticeable differentiation, while larger (˜70 - 100 nm diameter) nanotubes elicited a dramatic, ˜10 fold stem cell elongation, which induced cytoskeletal stress and selective differentiation into osteoblast-like cells, offering a promising nanotechnology-based route for novel orthopaedics-related hMSC treatments. The fact that a guided and preferential osteogenic differentiation of stem cells can be achieved using substrate nanotopography alone without using potentially toxic, differentiation-inducing chemical agents is significant, which can be useful for future development of novel and enhanced stem cell control and therapeutic implant development.

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