Top PDF Stem Cells in Regenerative Endodontics

Stem Cells in Regenerative Endodontics

Stem Cells in Regenerative Endodontics

Systematically, 2 distinctly different strategies exist involving stem cells for the repair and/or regeneration of damaged tissues: first, the acellular approach with in situ stimulation of stem cells and modulation of their activity and, second, the cellular approach consisting of ex vivo cell culture and the use of stem cells in tissue engineering.

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Trends in tissue repair and regeneration

Trends in tissue repair and regeneration

The Hydra polyp provides a unique system with which to investigate the mechanisms that maintain homeostasis, regeneration and slow ageing over many years. Brigitte Galliot (Geneva University, Switzerland) showed that H. vulgaris epithelial cells adapt to the loss of neurogenesis by overexpressing genes with potential neurogenic, neurotransmission or reprogramming functions (Wenger et al., 2016). By contrast, some H. oligactis strains lack this property, and animals rapidly lose regenerative capacity and develop an ageing phenotype. A positive role for senescent cells in regeneration has recently emerged as a new direction in the field (Demaria et al., 2014). Maximina Yun (University College London, UK) reported that, in salamander, endogenous senescent cells are detected during early phases of limb regeneration and are subsequently cleared by a ROS-dependent surveillance mechanism mediated by macrophages (Yun et al., 2015). Interestingly, transplantation of senescent cells into the regenerating blastema stimulates regeneration, whereas their elimination hinders it, highlighting their pro-regenerative nature. Similarly, Shahragim Tajbakhsh (Institut Pasteur, Paris, France) reported on a potentially positive role for cellular senescence in muscle regeneration in adult mice. Using Numb;Numbl conditional mutants in muscle stem cells, he showed that myogenic cells undergo cellular senescence following acute muscle injury, a process that is dependent on p53 (Trp53) and oxidative stress (Le Roux et al., 2015). Senescence of endothelial cells also occurs during early regeneration in wild-type mice, although this is independent of p53 and oxidative stress. These findings point to different modes by which senescent cells influence regeneration.
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Recombinant proteins in differentiation of stem cells

Recombinant proteins in differentiation of stem cells

Regarding cardiac cell-based treatments, stem cells are a promising cell source, which are being prioritized by scientists for basic research and clinical trials. 10,11 Several different human tissues have already been proposed as a source of stem cells with cardiogenic potential (therefore capable to generate new cardiomyocytes) (e.g., fetal cardiomyocytes, adult cardiac progenitor cells, skeletal myoblasts, bone marrow-derived stem cells, adipose-derived stem cells, umbilical cord-derived stem cells, and pluripotent stem cells), and some methods to isolate and expand these cells have been developed aiming cardiac regenerative therapy. 7,10–12 In this field, stem cell-derived cardiomyocytes would facilitate the discovery of small molecules promoting cardiomyocyte differentiation that could be used for the activation of endogenous cardiac stem cells in clinical settings. 12
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STEM CELLS AND REGENERATION

STEM CELLS AND REGENERATION

Remarkably, upon amputation the caudal fin regenerates the precise amount of tissue that was lost, at the correct location. This indicates that a positional memory instructs the blastema cells according to their proximo-distal fin localization (Lee et al., 2005). Coupled to this property, the regenerative process occurs independently of the number of amputations applied and animal age (Azevedo et al., 2011). Such properties indicate a tight growth control program, involving precise coordination between proliferation and positional information along the regenerating caudal fin. Although it is as yet unclear how these two central processes are molecularly controlled, they are likely to involve the integration of various signals. To date, fibroblast growth factor (FGF) is the only morphogen that has been shown to promote a proliferation rate increase in a proximal-distal gradient-like manner (Lee et al., 2005). Recently, inhibition of the phosphatase Calcineurin and of potassium channel activity were shown to be necessary for proportionate growth of the fin during development and regeneration (Perathoner et al., 2014; Kujawski et al., 2014). Clearly, further clarification of the cellular mechanisms that restrain uncontrolled proliferation is required in order to understand what regulates the final size of the renewed organ.
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Interface (Botucatu)  vol.11 número23 en a13v1123

Interface (Botucatu) vol.11 número23 en a13v1123

Borojevic (2004) describes regenerative medicine, a new specialty established within the medical field, whose goal is the repair or substitution of damaged or degenerate tissue. Bioengineering associates biomaterial with adjacent tissue cells in order to implant or promote the introduction of cells, seeking to integrate the resulting new structures with the damaged tissues. The use of stem cells in this process could permit the repetitive generation and recreation of tissue. Bone marrow is currently the principal source of stem cells for these therapies and the cells’ capacity to regenerate complex and functional tissue structures in situ is critical for their use in regenerative medicine. Some regenerative therapies seek to construct tissue in the laboratory for later implants and these have already demonstrated stem cells’ capabilities in vivo. Depending upon what disease is being treated, cellular therapy is a valid option. In cases of traumatic injuries accompanied by tissue or organ loss, for example, bioengineering and reparative cellular therapy can create adequate results. In the case of degenerative disease, however, Borojevic considers this sort of therapy to be palliative and also alerts readers as to common unrealistic or exaggerated expectations for stem cell therapies. There are many ethical objections to the use of cloned or embryonic stem cells, but none against the use of stem cells harvested from the patient herself (Borojevic, 2004).
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RGO, Rev. Gaúch. Odontol.  vol.65 número3

RGO, Rev. Gaúch. Odontol. vol.65 número3

Tissue engineering is a contemporary ield of science, which aims to create conditions based on principles of cell and molecular biology, bioengineering and biomaterials to regenerate tissues. Mesenchymal stem cells present high proliferation rates and are able to differentiate into multilineages under certain conditions, suggesting that they have great potential to act in regeneration ield. Tooth derived stem cells are a suitable alternative source of mesenchymal cells once they are easily accessible and have poor morbidity to the donor. Studies showed that they have been isolated and characterized from diverse tissues such as dental pulp, exfoliated deciduous teeth, periodontal ligament, gingiva, dental follicle and apical papilla. However studies show that there is heterogeneity among these populations and there is no standard method to select the most appropriate tooth derived stem cells for regenerative procedures. The aim of this review is to present the current perspective of the multiple types of tooth-derived stem cells and to discuss the basis for their use in periodontal tissue engineering.
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Platelet-rich plasma and adipose-derived mesenchymal stem cells for regenerative medicine-associated treatments in bottlenose dolphins (Tursiops truncatus).

Platelet-rich plasma and adipose-derived mesenchymal stem cells for regenerative medicine-associated treatments in bottlenose dolphins (Tursiops truncatus).

Figure 3. Dolphin PRP induces proliferation and phagocytic activity of dolphin ASCs. (A) Adipose tissue was collected from the postnuchal fat pad from recent postmortem wild striped dolphins (Stenella coeruleoalba) (n = 2) and dolphin ASCs were derived and characterized. (B) Dolphin ASCs are plastic adherent and are able to be cultured in the presence of both 10% FBS and 10% dolphin serum. The morphology of ASCs treated with 10% dolphin serum appeared less elongated and senescent compared to those cultured with 10% FBS. (C) Dolphin ASCs were positive for mesenchymal cell markers CD90, CD44, and CD105 and were negative for hematopoietic cell markers CD34 and CD45. The histograms for CD90, CD44, and CD105 show the shift in the positive population in pink versus the non-stained sample in blue. CD34 and CD45 did not show positive reactivity, thereby confirming that the putative ASCs are indeed of mesenchymal origin. (D) Dolphin ASCs were capable of tri-lineage mesenchymal differentiation. ASCs were differentiated under standard in vitro conditions to adipocytes (Oil Red O staining), osteocytes (Alizarin Red staining) and chondrocytes (Alcian blue staining). (E) Dolphin ASCs treated in vitro with 2.5 or 5% dolphin PRP exhibited significantly increased proliferation, while those treated with 1% PRP were not different than controls. Proliferation rates in ASCs treated with the same concentrations of FBS were similar but significantly lower at 2.5 and 5% compared to PRP. Morphologically there was an increase in the number and density of ASCs cultured with 2.5 or 5% PRP compared to controls. Representative images of dolphin ASCs treated with 0 or 5% dolphin PRP are shown. Results of MTS assays are mean 6 SD of colorimetric signal from treated cells in the presence of 1, 2.5, or 5% PRP compared to the absence of PRP. Every condition was assayed in quadruplicate in three different experiments for both lines of dolphin ASCs. (F) In addition to inducing proliferation of ASCs, treatment with 5% PRP stimulates phagocytic activity in dolphin ASCs. Red fluorescent microspheres were highly phagocytosed by ASCs in the presence of PRP compared to those without PRP (upper panels). Similarly, when fixed and stained with Giemsa, there were clearly more ASCs indicating increased proliferation. Also visible are the increased number of microspheres which have been phagocytosed within the ASCs treated with 5% PRP compared to fewer microspheres inside untreated ASCs. Asterisks denote significant difference compared to controls (0% or PRP or FBS) * P,0.05.
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Stem cells and bioengineering in the current context of dentistry and general health / Células-tronco e bioengenharia no contexto atual da odontologia e saúde geral

Stem cells and bioengineering in the current context of dentistry and general health / Células-tronco e bioengenharia no contexto atual da odontologia e saúde geral

This literature review focused on mesenchymal stem cells - in particular DPSC, SHED, PDLSC, DFSC and SCAP - with regard to their contribution and effectiveness in dental treatments or not. Based on the studies presented, these cells have, in fact, a broad perspective of application in tissue bioengineering and cell therapies, due to their easy and less invasive collection combined with their regenerative, anti-inflammatory and immunomodulatory properties. In addition, despite the reduced number of studies, MSC are also promising in the treatment of complications caused by SARS-CoV-2. In a culture medium composed of the presented triad, DSC demonstrates their ability to differentiate into multiple cell lines. In this context, understanding the functioning of these cells and their properties allows the development of more effective therapies or even the cure of diseases, such as Severe Acute Respiratory Syndrome.
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Avaliação de peptídeos antimicrobianos e imunomoduladores : novas estratégias biotecnológicas para o preparo do dente para a revascularização pulpar

Avaliação de peptídeos antimicrobianos e imunomoduladores : novas estratégias biotecnológicas para o preparo do dente para a revascularização pulpar

Recent regenerative therapies such as pulpal revascularization have been diffused in endodontics in immature permanent teeth. However, the use of medications such as double antibiotic paste (DAP) containing metronidazole (MTZ) and ciprofloxaxin (CIP) or triple antibiotic paste (TAP) containing CIP, MTZ and minocycline may cause resistance, cytotoxicity and dentin discoloration. On the other hand, host defense peptides (HDPs) have antimicrobial and immunomodulatory effects, emerging as an option for pulpal revascularization. Thus, the aim of this study was to evaluate the antimicrobial and immunomodulatory potential of synthetic peptides (DJK-6, IDR-1018, IDR-1002 and LL-37) compared to TAP and DAP, in an in vitro endodontic infection model. For this, the study was divided in three stages: (1) antimicrobial potential of TAP and DAP drugs (alone or in combination) and HDPs against the bacteria Staphylococcus aures (S.a.) and Enterococcus faecalis (E.f.) and the synergistic potential of CIP and IDR-1002; (2) comparison of the findings of this study with TAP and DAP clinical concentrations, through cell viability by MTT and nitric oxide (NO) production by the Griess reaction, in RAW 264.7 macrophages and L929 fibroblasts; (3) immunomodulatory stage, by the evaluation of cytokines by ELISA: IL-1α, IL-6, IL- 12, IL-10 and tumor necrosis factor (TNF-α), as well as NO in RAW 264.7 (RAW) and IL-6 and NO, in L929 with or without the recombinant interferon gamma (rIFN-γ) and heat killed antigens HK-S.a. or HK-E.f. In the first stage, CIP presented the best antimicrobial activity comparing to TAP and DAP containing antibiotics and IDR-1002, the best HDP. In addition, the combination between CIP and IDR-1002 was synergistic. The viability was not reduced by any groups and TAP stimulated NO production in RAW cells. Finally, LL-37 significantly reduced the viability of L929 and TAP, the RAW viability. Without any antigenic stimuli, TAP and DAP presented a pro-inflammatory profile up regulating IL-1α, TNF-α and IL-6 in RAW and IL-6, in L929. However, the addition of antigenic stimuli and rIFN-γ, TAP and DAP presented pro and anti- inflammatory profile reducing IL-1α, IL-12 and IL-6 in RAW and increasing TNF-α and NO, and reducing IL-1α, IL-10 and IL-6 in RAW and increasing IL-12. CIP, LL-37, IDR- 1002 and the combination of CIP with IDR-1002 showed an anti-inflammatory profile, mainly reducing IL-6 and IL-12 with antigenic and rIFN-γ stimuli. In conclusion, the synergistic combination of CIP with IDR-1002 was effective against both bacteria and presented an anti-inflammatory role in this in vitro infection model may emerge as a promising option for biotechnological applications involving pulp revascularization.
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Stromal cells in the hematopoietic-stem-cell niche

Stromal cells in the hematopoietic-stem-cell niche

Mesenchymal stem cells (MSC) are multipotential nonhematopoietic progenitor cells capable of differentiating into multiple mesenchymal tissues. MSC are able to reconstitute the functional human hematopoietic microenvironment and promote en- graftment of hematopoietic stem cells. MSC constitutively express low levels of major histocompatibility complex-I molecules and do not express costimulatory molecules such as CD80, CD86 or CD40, thus lacking immunogenicity. Furthermore, they are able to suppress T- and B-lymphocyte activation and proliferation and may also affect dendritic cell maturation. Based on these properties, MSC are being used in regenerative medicine and also for the treatment of autoimmune diseases and graft- versus-host disease. On the other hand, MSC from patients diagnosed with myelodysplastic syndromes or multiple myeloma display abnormalities, which could play a role in the physiopathology of the disease. Finally, in patients with immune throm- bocytopenic purpura, MSC have a reduced proliferative capacity and a lower inhibitory effect on T-cell proliferation compared with MSC from healthy donors.
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Dental follicle cells rescue the regenerative capacity of periodontal ligament stem cells in an inflammatory microenvironment.

Dental follicle cells rescue the regenerative capacity of periodontal ligament stem cells in an inflammatory microenvironment.

HPDLSCs and PPDLSCs were successfully isolated from PDL tissues derived from healthy donors and patients diagnosed with periodontitis, respectively. Putative stem cells were isolated using a limiting dilution technique and cultured to the third passage. Additionally, DFCs were harvested from dental follicle tissue and cultured to the third passage. Using a microscope, HPDLSCs, PPDLSCs, and DFCs were observed growing in an adherent manner with a long spindle shape. Although no obvious difference was observed between HPDLSCs and PPDLSCs, PPDLSCs appeared slightly irregular (Figure 1A). All three cell populations expressed the mesenchymal stem cell markers Stro-1, CD146, CD105, CD90, and CD29 and were negative for the hematopoi- Figure 5. Effects of DFCs on cell sheet formation by HPDLSCs and PPDLSCs in vitro. A: H&E staining of cell sheets. HPDLSCs formed more cell layers and ECM than PPDLSCs. In the co-cultured systems, both HPDLSCs and PPDLSCs formed more cell layers and ECM than in the monocultured systems (hematoxylin-eosin staining, magnification: 4006, scale bar = 50 mm). B: SEM of cell sheets; HPDLSCs secreted richer ECM than PPDLSCs, and co-culture with DFCs enhanced the ECM secretion by both HPDLSCs and PPDLSCs. Notes: DFCs (–), monocultured PDLSCs that were cultured with transwell containing no DFCs; DFCs (+), co-cultured PDLSCs that were cultured with transwells seeded with a specific number of DFCs.
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Mesenchymal stem cells secretome in Parkinson’s disease regenerative medicine

Mesenchymal stem cells secretome in Parkinson’s disease regenerative medicine

Neurotrophic growth factors such as NGF, BDNF, GDNF have also been found to be increased after NSCs transplantation (Drago et al., 2013). Likewise MSCs, currently there are no studies regarding the application of NSCs secretome alone in animal models of PD. However, studies have suggested NSCs as neurotrophic-factor secreting cells (Drago et al., 2013). For instance, Yasuhara and co-workers (Yasuhara et al., 2006) showed that after intrastriatal transplantation of NSCs in 6-OHDA PD model, there was an improvement in the behavioral performance of the animals, which was correlated with the increase of TH innervation due to an active expression of SCF. Similar outcomes were also presented by Ourednik and colleagues (Ourednik et al., 2002), which demonstrated, using a MPTP PD model, that after the transplantation of NSCs there was an increased recovery of TH and DAT activity due to an in situ expression of GDNF. Moreover, the authors suggest that the NSCs have the capacity to create host environments rich in trophic and neuroprotective support to rescue imperiled host cells (Ourednik et al., 2002). Ebert and colleagues (Ebert et al., 2008) demonstrated that NSCs overexpressing either IGF-1 or GNDF were able to significantly reduce amphetamine-induce rotational behavior and DA neuronal loss in 6-OHDA PD animals, when compared to the untransduced NSCs. Behrstock et al. (Behrstock et al., 2006) demonstrated, in vitro, that the number of primary neurons staining for TH significantly increased after the addition of NSCs CM. In vivo, using NSCs genetically modified to release GDNF, the same authors showed that more TH positive neurons were present in the transplanted rats (partial lesioned with 6-OHDA), verifying fewer rotations compared to the untransplanted group (Behrstock et al., 2006).
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RGO, Rev. Gaúch. Odontol.  vol.65 número4

RGO, Rev. Gaúch. Odontol. vol.65 número4

Regenerative therapies have been widely developed in dentistry and it is important to incorporate dentists’ knowledge of these new therapies into the dental clinic routine. This study reviewed the literature on regenerative therapies and clinical applications. Tissue engineering has contributed to changes in the paradigm of restorative health sciences. Its pillars underpin the techniques of tissue and organ regeneration. Despite the majority of studies in this ield being in vitro, a range of preclinical studies and methodologies has been formed using these principles and they are already being used on humans. The use of platelet-rich plasma and platelet-rich ibrin in surgery as natural scaffolds for the reestablishment of bone and periodontal tissue are often reported in the literature and clinical trials using this approach have shown promising results. Stem cells from autologous dental pulp have been successfully applied in bone tissue regeneration using natural collagen scaffold in humans. In addition, revascularization of the root canal already appears in the literature as a promising alternative to apexiication. The principle behind this therapy is the use of the blood clot as a scaffold and the migration of stem cells of the apical papilla to regenerate the dental pulp organ. Final considerations: Although still in the early stages, regenerative therapies can now be used in dental practice. Knowledge of the principles governing these therapies should be understood by the dentist for use in clinical practice.
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Dissecting lineage priming in mouse embryonic stem cells

Dissecting lineage priming in mouse embryonic stem cells

7 In the mouse embryo after implantation, as described in section 1.1, the pluripotent epiblast undergoes morphological and transcriptional modifications. Around E6.5 (Figure 1), gastrulation begins with the formation of the node that acts as a body plan organizer, on the posterior side of the epiblast. From the node, a structure called primitive streak is formed. With the formation of the primitive streak, the anterior-posterior axis becomes morphologically obvious with the streak located on the posterior side of the embryo. The cells that move through the streak become mesendoderm, which are the precursors of mesoderm and endoderm cells. Anteriorly, the acquisition of neural fate is achieved by the induction of the anterior neural plate derived from the anterior epiblast, while the posterior neural plate arises from regionalization of the anterior neuroectoderm through “posteriorizing” signals. This model is derived from the “activation-transformation” hypothesis proposed by Nieuwkoop in 1952 49 . More recently, the
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Stem and progenitor cell-mediated tumor selective gene therapy

Stem and progenitor cell-mediated tumor selective gene therapy

that survived had incorporated the exogenous nucleotide sequence at sites adjacent to loci encoding LMO2, LYL1, c-Jun, Bmi1 or CCND2. Insertions at these sites upregu- lated expression of genes, which, when highly expressed, transformed T cells. The critical concern becomes, in any given cell type, if an exogenous gene or cDNA inserts into the host cell genome, is the expression of any ‘nearby’ gene altered and is upregulation of that gene likely to impact on the phenotype of the type of cell into which the gene was inserted? (It should be noted that cell lines immortalized using retroviruses to insert hTERT, SV40 large T, Bmi-1 and E6/E7 have not been extensively characterized. Since insertion sites were not mapped, hTERT itself may not be tumorigenic, but its insertion may have disrupted another critical genomic locus and transformed the delivery cell. Before telomerase-immor- talized cell lines are used clinically, it will be essential to determine which of these alternatives is responsible for any observed tumor development.) In leukocytes, un- fortunately, there is documentation from clinical trials that insertion of an exogenous gene near at least five specific genetic loci increases the tumorigenic potential. Based on these data, one would postulate that if cells of neuronal, rather than hematopoietic, origin were used as delivery vehicles it would be important to determine that insertion of exogenous sequences near genetic loci encoding MYC-N or EGFR, for example, did not alter expression of these genes. Pike-Overzet et al. 88 suggest
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A defined, feeder-free, serum-free system to generate in vitro hematopoietic progenitors and differentiated blood cells from hESCs and hiPSCs.

A defined, feeder-free, serum-free system to generate in vitro hematopoietic progenitors and differentiated blood cells from hESCs and hiPSCs.

cells [29–35]). Recently, three groups have reported megakaryocyte differentia- tion from hESC lines using the murine OP9 co-culture system [25,36,37] and one group using the EB method [38]. Our work presents, therefore, for the first time a protocol devoid of serum and other undefined conditions to obtain megakaryocytes from hESCs and hiPCSs capable of shedding platelets in vitro. Obtaining large quantities of megakaryocytes in vitro could offer a valuable example of using hESC/hiPSC-derived cells to study disorders affecting a rare population of cells (megakaryocyte represent 0.1% of the nucleated cells in the bone marrow), but most importantly could set the stage for the production of a cell type, which could be used in clinical settings. It has been proposed that co-transplan- tation of autologous megakaryocytes together with hematopoietic stem cells could result in higher response and survival rates for patients afflicted by the severe thrombocytopenia often associated with high dose chemotherapy and radiation therapy [39]. The advantage of using autologous cells in transplantation studies prompted us to test our protocol on nine hiPSC lines generated in our laboratories using retroviral transduction of cells of different tissue origin. HiPSCs have already been shown to be able to differentiate into various lineages, such as cardiac [40], pancreatic [41], hepatic [42], epithelial [6,43,44], neuronal [45–47], adipose [48], and endothelial and hematopoietic [6,11,49–51]. The fast pace of basic research on hiPSCs since their discovery in 2007 [52,53] reflects the high value of these new pluripotent lines for drug testing, preclinical models and clinical application. For the potential use of hiPSCs in pre- and clinical settings the major challenge is to define culture conditions to differentiate progenitor cells into a selected lineage with high efficiency and purity. Here we tested several hiPSC lines generated by our group for their ability to differentiate into hematopoietic progenitors using the 2D protocol optimized on a hESC line. Despite some expected differences in differentiation efficiency, we were able to generate hematopoietic progenitors from nine hiPSC lines derived from 5 different tissue types. As proof of principle we generated
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Rev. Bras. Hematol. Hemoter.  vol.38 número1

Rev. Bras. Hematol. Hemoter. vol.38 número1

The addition of plerixafor shows a consistent increase in collection rate success, reducing the number of apheresis and not increasing toxicity. Strategies of preemptive use of plerix- afor have been considered a promising way to optimize and rationalize the use of this agent in patients who have high chance of failure with classic mobilization based on G-CSF with or without chemotherapy. This strategy would reduce failure in mobilization, especially in poor mobilizers, ensuring collection and transplantation as well as reducing time and costs of the mobilization procedure. However, external valid- ity of these algorithms is limited, so it is recommended that each institution sets up a strategy appropriate to its standards for the preemptive use of plerixafor.
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Expression and secretion of human recombinant LIF by genetically modified mammalian cells

Expression and secretion of human recombinant LIF by genetically modified mammalian cells

При куль ти ви ро ва нии кле ток in vitro в сре ду до - бав ля ют очи щен ные ре ком би нан тные рос то вые фак то ры, ци то ки ны и дру гие би о ло ги чес ки ак тив - ные мо ле ку лы или ис поль зу ют кон ди ци о ни ро ван - ные сре ды [15, 16]. Инак ти ва ция рос то вых фак то - ров тре бу ет по сто ян ной за ме ны сре ды, по э то му раз ра ба ты ва ют и дру гие под хо ды к об ес пе че нию эф фек тив но го мик ро ок ру же ния куль ти ви ру е мых кле ток, в час тнос ти, ис поль зу ют им мо би ли зо ван - ные рос то вые фак то ры [17] и транс ген ные кле точ - ные ли нии, ко то рые мо гут слу жить фи дер ны ми клет ка ми [18–20]. По лу че ние транс ген ных кле точ - ных ли ний раз но го про ис хож де ния да ет воз мож - ность ре шать ряд за дач, свя зан ных, сре ди про че го, с из уче ни ем вли я ния транс ге на на би о ло гию клет - ки-ре ци пи ен та. Кро ме это го, экс прес сия ре ком би - нан тных бел ков в клет ках мле ко пи та ю щих яв ля ет - ся основ ным ис точ ни ком по лу че ния гли ко зи ли ро - ван ных бел ков.
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Xinghui Song1 , Yanwei Li1 , Xiao Chen2

Xinghui Song1 , Yanwei Li1 , Xiao Chen2

In this study, ESCs were cultured on mouse embry- onic fibroblasts. These cells can be cultured, passaged and cryopreserved, and retain their proliferative capacity after continuous passage. Several totipotency molecular markers with an important role in maintaining the capacity for self-renewal (Eiges et al., 2001; Richards et al., 2002) oc- cur in these cells, including stage-specific embryonic anti- gens (SSEA-1, SSEA-3, SSEA-4), transcriptional regulation antigens (TRA-1-60, TRA-1-81), homologous protein transcription factor (Nanog) and transcription fac- tors OCT3\4 and SOX-2. As shown here, three germ layer teratomas were also generated. These results indicate these cells are totipotent and that the method for establishing them is feasible. MSCs were generated from ESCs. With continuous passage, the cells began to form fibroblast colo- nies. MSCs can proliferate indefinitely while retaining their potential for differentiation, as shown by the identification of totipotency factors. Indeed, MSCs were totipotent and could differentiate into osteoblasts, chondrocytes and adipocytes after stimulation with a specific inducer. MSCs can therefore be regarded as seed cells for tissue engineer- ing. The relatively controllable differentiation may provide a new approach for adipose tissue engineering.
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Co- transplantation of Bone Marrow Stromal Cells with Schwann Cells Evokes Mechanical Allodynia in the Contusion Model of Spinal Cord Injury in Rats

Co- transplantation of Bone Marrow Stromal Cells with Schwann Cells Evokes Mechanical Allodynia in the Contusion Model of Spinal Cord Injury in Rats

Different researchers have demonstrated that transplantation of stem cells like bone marrow stromal cells (BMSCs) (9), Schwann cells (SCs) (10), neural stem cells (NSCs) (11[r]

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