Advances in Dental Pulp Stem Cell Biology for Biomedical Engineering (Preprint)

2020 ◽  
Author(s):  
Sejin Bae ◽  
Byeonguk Kang ◽  
Hyungbin Lee ◽  
Harrison Luu ◽  
Eric Mullins ◽  
...  

BACKGROUND Many studies in stem cell biology have demonstrated that dental pulp stem cells (DPSC) may be highly proliferative and capable of pluripotent differentiation into many different tissue types. Recent advances in stem cell research have outlined methods for directing in vitro or in vivo differentiation of DPSC - although much remains to be discovered. OBJECTIVE Based upon this information, the primary objective of this study was to understand the biology and biotechnology needed to more effectively direct DPSC differentiation. METHODS Previously collected and isolated samples of DPSC from an existing repository were used. Due to the use of previously collected, non-identifiable samples this protocol was granted exemption from Human Subjects review. Previously established stem cell biomarkers (Sox-2, Oct-4, NANOG) from each isolate were correlated with their proliferation rates or doubling times to categorize them into rapid, intermediate, or slow-dividing multipotent DPSC. Growth factors and other dental biomaterials were subsequently tested to evaluate DPSC responses in proliferation, viability and morphology. RESULTS Differential responses were observed among DPSC isolates to growth factors, including vascular endothelial growth factor (VEGF) and bone morphogenic protein (BMP-2), and biomaterials such as mineralized trioxide aggregates (MTA). The responsiveness of DPSC isolates did not correlate with any single factor but rather with a combination of proliferation rate and biomarker expression. CONCLUSIONS These data strongly suggest that some, but not all DPSC isolates are capable of a robust and significant in vitro response to differentiation stimuli, although this response is not universal. Although some biomarkers and phenotypes that distinguish and characterize these DPSC isolates may facilitate the ability to predict differentiation potential, more research is needed to determine the other intrinsic and extrinsic factors that may contribute to and modulate these DPSC responses for biotechnology and bioengineering applications. CLINICALTRIAL N/A (not applicable)

2021 ◽  
Vol 12 (1) ◽  
pp. 15
Author(s):  
Sejin Bae ◽  
Bueonguk Kang ◽  
Hyungbin Lee ◽  
Harrison Luu ◽  
Eric Mullins ◽  
...  

Introduction: Many studies in stem cell biology have demonstrated that dental pulp stem cells (DPSC) may be highly proliferative and capable of pluripotent differentiation into many different tissue types. Recent advances in stem cell research have outlined methods for directing in vitro or in vivo growth, viability, and proliferation, as well as differentiation of DPSC—although much remains to be discovered. Based upon this information, the primary objective of this study was to understand the functional biomaterials needed to more effectively direct DPSC viability, growth, and proliferation. Methods: Using an approved protocol, previously collected and isolated samples of DPSC from an existing repository were used. Previously established stem cell biomarkers (Sox-2, Oct-4, NANOG) from each isolate were correlated with their proliferation rates or doubling times to categorize them into rapid, intermediate, or slow-dividing multipotent DPSC. Growth factors and other functional dental biomaterials were subsequently tested to evaluate DPSC responses in proliferation, viability, and morphology. Results: Differential responses were observed among DPSC isolates to growth factors, including vascular endothelial growth factor (VEGF) and bone morphogenic protein (BMP-2), and functional biomaterials such as mineralized trioxide aggregates (MTA). The responsiveness of DPSC isolates did not correlate with any single factor but rather with a combination of proliferation rate and biomarker expression. Conclusions: These data strongly suggest that some, but not all, DPSC isolates are capable of a robust and significant in vitro response to differentiation stimuli, although this response is not universal. Although some biomarkers and phenotypes that distinguish and characterize these DPSC isolates may facilitate the ability to predict growth, viability, and differentiation potential, more research is needed to determine the other intrinsic and extrinsic factors that may contribute to and modulate these DPSC responses to these functional biomaterials for biotechnology and bioengineering applications.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 95-95 ◽  
Author(s):  
Keisuke Ito ◽  
Paolo Sportoletti ◽  
John G Clohessy ◽  
Grisendi Silvia ◽  
Pier Paolo Pandolfi

Abstract Abstract 95 Myelodysplastic syndrome (MDS) is an incurable stem cell disorder characterized by ineffective hematopoiesis and an increased risk of leukemia transformation. Nucleophosmin (NPM) is directly implicated in primitive hematopoiesis, the pathogenesis of hematopoietic malignancies and more recently of MDS. However, little is known regarding the molecular role and function of NPM in MDS pathogenesis and in stem cell biology. Here we present data demonstrating that NPM plays a critical role in the maintenance of hematopoietic stem cells (HSCs) and the transformation of MDS into leukemia. NPM is located on chromosome 5q and is frequently lost in therapy-related and de novo MDS. We have previously shown that Npm1 acts as a haploinsufficient tumor suppressor in the hematopoietic compartment and Npm1+/− mice develop a hematologic syndrome with features of human MDS, including increased susceptibility to leukemogenesis. As HSCs have been demonstrated to be the target of the primary neoplastic event in MDS, a functional analysis of the HSC compartment is essential to understand the molecular mechanisms in MDS pathogenesis. However, the role of NPM in adult hematopoiesis remains largely unknown as Npm1-deficiency leads to embryonic lethality. To investigate NPM function in adult hematopoiesis, we have generated conditional knockout mice of Npm1, using the Cre-loxP system. Analysis of Npm1 conditional mutants crossed with Mx1-Cre transgenic mice reveals that Npm1 plays a crucial role in adult hematopoiesis and ablation of Npm1 in adult HSCs leads to aberrant cycling and followed by apoptosis. Analysis of cell cycle status revealed that HSCs are impaired in their ability to maintain quiescence after Npm1-deletion and are rapidly depleted in vivo as well as in vitro. Competitive reconstitution assay revealed that Npm1 acts cell-autonomously to maintain HSCs. Conditional inactivation of Npm1 leads to an MDS phenotype including a profoundly impaired ability to differentiate into cells of the erythroid lineage, megakaryocyte dyspoiesis and centrosome amplification. Furthermore, Npm1 loss evokes a p53-dependent response and Npm1-deleted HSCs undergo apoptosis in vivo and in vitro. Strikingly, transfer of the Npm1 mutation into a p53-null background rescued the apoptosis of Npm1-ablated HSCs and resulted in accelerated transformation to an aggressive and lethal form of acute myeloid leukemia. Our findings highlight the crucial role of NPM in stem cell biology and identify a new mechanism by which MDS can progress to leukemia. This has important therapeutic implications for de novo MDS as well as therapy-related MDS, which is known to rapidly evolve to leukemia with frequent loss or mutation of TRP53. Disclosures: No relevant conflicts of interest to declare.


2018 ◽  
pp. 1402-1423
Author(s):  
Martin Reinhardt ◽  
Shibashish Giri ◽  
Augustinus Bader

Currently, practical application of nanotechnological approaches and stem cell therapies remains a challenge in both preclinical and clinical settings. Many existing problems in tissue engineering to organ engineering have been solved by the combined approaches of nanotechnology and stem cell biology, but significant barriers remain. Details about the role of various types of nanomaterial in preclinical and clinical research have been reviewed elsewhere, but scant information exists about the influence of nanomaterials on stem cell biology. Herein, the authors highlight the current advances of nanotechnological approaches for expansion, differentiations, harvesting, labeling, imagining, tissue engineering, and organ engineering of different types of stem cells. The preclinical outcome of in vitro and in vivo animal experimentations along with some examples of clinical outcomes of nanomaterials on stem cell research is the main focus of this chapter. This book chapter might be an impetus for the present generation of young scientists to revolutionize the coming generation of effective human healthcare.


2021 ◽  
Vol 12 ◽  
Author(s):  
Xu Cheng ◽  
Bing Shi ◽  
Jingtao Li

Craniofacial muscles emerge as a developmental novelty during the evolution from invertebrates to vertebrates, facilitating diversified modes of predation, feeding and communication. In contrast to the well-studied limb muscles, knowledge about craniofacial muscle stem cell biology has only recently starts to be gathered. Craniofacial muscles are distinct from their counterparts in other regions in terms of both their embryonic origin and their injury response. Compared with somite-derived limb muscles, pharyngeal arch-derived craniofacial muscles demonstrate delayed myofiber reconstitution and prolonged fibrosis during repair. The regeneration of muscle is orchestrated by a blended source of stem/progenitor cells, including myogenic muscle satellite cells (MuSCs), mesenchymal fibro-adipogenic progenitors (FAPs) and other interstitial progenitors. Limb muscles host MuSCs of the Pax3 lineage, and FAPs from the mesoderm, while craniofacial muscles have MuSCs of the Mesp1 lineage and FAPs from the ectoderm-derived neural crest. Both in vivo and in vitro data revealed distinct patterns of proliferation and differentiation in these craniofacial muscle stem/progenitor cells. Additionally, the proportion of cells of different embryonic origins changes throughout postnatal development in the craniofacial muscles, creating a more dynamic niche environment than in other muscles. In-depth comparative studies of the stem cell biology of craniofacial and limb muscles might inspire the development of novel therapeutics to improve the management of myopathic diseases. Based on the most up-to-date literature, we delineated the pivotal cell populations regulating craniofacial muscle repair and identified clues that might elucidate the distinct embryonic origin and injury response in craniofacial muscle cells.


Author(s):  
Martin Reinhardt ◽  
Shibashish Giri ◽  
Augustinus Bader

Currently, practical application of nanotechnological approaches and stem cell therapies remains a challenge in both preclinical and clinical settings. Many existing problems in tissue engineering to organ engineering have been solved by the combined approaches of nanotechnology and stem cell biology, but significant barriers remain. Details about the role of various types of nanomaterial in preclinical and clinical research have been reviewed elsewhere, but scant information exists about the influence of nanomaterials on stem cell biology. Herein, the authors highlight the current advances of nanotechnological approaches for expansion, differentiations, harvesting, labeling, imagining, tissue engineering, and organ engineering of different types of stem cells. The preclinical outcome of in vitro and in vivo animal experimentations along with some examples of clinical outcomes of nanomaterials on stem cell research is the main focus of this chapter. This book chapter might be an impetus for the present generation of young scientists to revolutionize the coming generation of effective human healthcare.


2006 ◽  
Vol 191 (1) ◽  
pp. 101-111 ◽  
Author(s):  
David J Flint ◽  
Nadine Binart ◽  
Stephanie Boumard ◽  
John J Kopchick ◽  
Paul Kelly

Direct metabolic effects of GH on adipose tissue are well established, but effects of prolactin (PRL) have been more controversial. Recent studies have demonstrated PRL receptors on adipocytes and effects of PRL on adipose tissue in vitro. The role of GH in adipocyte proliferation and differentiation is also controversial, since GH stimulates adipocyte differentiation in cell lines, whereas it stimulates proliferation but inhibits differentiation of adipocytes in primary cell culture. Using female gene disrupted (ko) mice, we showed that absence of PRL receptors (PRLRko) impaired development of both internal and s.c. adipose tissue, due to reduced numbers of adipocytes, an effect differing from that of reduced food intake, where cell volume is decreased. In contrast, GHRko mice exhibited major decreases in the number of internal adipocytes, whereas s.c. adipocyte numbers were increased, even though body weight was decreased by 40–50%. The changes in adipose tissue in PRLRko mice appeared to be entirely due to extrinsic factors since preadipocytes proliferated and differentiated in similar fashion to wild-type animals in vitro and their response to insulin and isoproterenol was similar to wild-type animals. This contrasted with GHRko mice, where s.c. adipocytes proliferated, differentiated, and responded to hormones in identical fashion to controls, whereas parametrial adipocytes exhibited markedly depressed proliferation and differentiation potential and failed to respond to insulin or noradrenaline. Our results provide in vivo evidence that both GH and PRL stimulate differentiation of adipocytes but that the effects of GH are site specific and induce intrinsic changes in the precursor population, which are retained in vitro.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 1705-1705
Author(s):  
Joyce S.G Yeoh ◽  
Ronald van Os ◽  
Ellen Weersing ◽  
Bert Dontje ◽  
Edo Vellenga ◽  
...  

Abstract Fibroblast Growth Factors (FGF) are a large family of signaling molecules widely involved in tissue development, maintenance and repair. Little is known about the role of FGF/FGF-receptor signaling in the regulation of adult hematopoietic stem cells (HSC). In this study, we assessed the potential of exogenously added FGF-1/2, or retrovirally overexpressed FGF-1 to preserve HSC function in vitro and in vivo. First, we demonstrate that in vitro culture of unfractionated mouse bone marrow cells, in serum-free medium, supplemented with FGF-1 or FGF-2 or FGF-1 + 2 resulted in the robust generation of long-term repopulating (LTR) HSCs. Cultures were maintained for 12 weeks and during that time in vivo competitive reconstitution assays were performed. Stem cell activity was detectable at 3, 5, and 8 weeks after initiation of culture, but lost after 12 weeks. However, whereas 3 and 5 week cultured cells provided radioprotection in non-competitive assays, animals transplanted with 8 or 12 week cultured cells succumbed due to bone marrow failure. So far, we have been unable to expand single, highly purified Lin−Sca-1+c-Kit+ using FGF-1 + 2. Consequently, we speculated that essential intermediate cell populations or signals are required for FGF-induced stem cell conservation. To test this we cultured highly purified CD45.1 Lin−Sca-1+c-Kit+ cells in a co-culture with CD45.2 unfractionated BM. Co-cultured cells were transplanted after 5 weeks in lethally irradiated recipients, and CD45.1 chimerism levels were assessed. High levels of CD45.1 chimerism confirmed that Lin−Sca-1+c-Kit+ cells require an accessory signal in addition to FGF to induced stem cell activity in vitro. We subsequently tested stem cell potential of cells cultured in FGF-1 + 2 for 5 weeks, with the addition of SCF + IL-11 + Flt3L for the last 2, 4 or 7 days. Cell numbers increased with increasing time of growth factor presence. However, only when growth factors were present for 2 days engraftment of cultured cells in a competitive repopulation assay was increased 3.5-fold. Finally, we show by immunohistochemistry that ~10% of freshly isolated Lin−Sca-1+c-Kit+ expresses high levels of FGF-1. Retroviral overexpression of FGF-1 in stem cells resulted in increased growth potential and sustained clonogenic activity in vitro. Upon transplantation of transduced stem cells, FGF-1 overexpression resulted in increased white blood cell counts 4 weeks post-transplant compared to control animals. Most notable was a marked granulocytosis in FGF-1 overexpressing recipients Our results reveal FGF as an important regulator of HSC signaling and homeostasis. Importantly, in the presence of FGF stem cells can be maintained in vitro for 2 months. These findings open novel avenues for in vitro manipulation of stem cells for future clinical therapies.


2009 ◽  
Vol 390 (10) ◽  
Author(s):  
Claus Kordes ◽  
Iris Sawitza ◽  
Dieter Häussinger

Abstract Stellate cells are vitamin A-storing cells of liver and pancreas and have been described in all vertebrates ranging from lampreys (primitive fish) to humans, demonstrating their major importance. This cell type is thought to contribute to fibrosis, a condition characterized by an excess deposition of extracellular matrix proteins. Recently, the expression of stem/progenitor cell markers, such as CD133 (prominin-1) and Oct4, was discovered in hepatic stellate cells (HSCs) of rats. Moreover, HSCs possess signaling pathways important for maintenance of stemness and cell differentiation, such as hedgehog, β-catenin-dependent Wnt, and Notch signaling, and are resistant to CD95-mediated apoptosis. In analogy to a stem cell niche, some characteristics of quiescent HSC are maintained by aid of a special microenvironment located in the space of Dissé. Finally, stellate cells display a differentiation potential as investigated in vitro and in vivo. Collectively all these properties are congruently found in stem/progenitor cells and support the concept that stellate cells are undifferentiated cells, which might play an important role in liver regeneration. The present review highlights findings related to this novel aspect of stellate cell biology.


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