Human Placenta-derived Stem Cells Research Articles

Biosponge-Encased Placental Stem Cells for Volumetric Muscle Loss Repair.

Objective: Volumetric muscle loss (VML) leads to permanent muscle mass and functional impairments. While mesenchymal stromal cells (MSCs) and their secreted factors can aid muscle regeneration, MSCs exhibit limited persistence in injured tissue post-transplantation. Human placental-derived stem cells (hPDSCs), sharing surface markers with MSCs, demonstrate superior regenerative potential due to their fetal origin. Previously, a biosponge (BS) scaffold was shown to augment muscle regeneration post-VML. This study aims to coapply BS therapy and hPDSCs to further enhance muscle recovery following VML. Approach: A VML defect was created by removing ∼20% of the tibialis anterior muscle mass in male Lewis rats. Injured muscles were either left untreated or treated with BS or BS-encapsulated hPDSCs cultured under normoxic or hypoxic conditions. On day 28 postinjury, peak isometric torque was measured, and the muscle was harvested for analysis. Results: BS encapsulated hPDSCs subjected to hypoxic preconditioning persisted in larger quantities and enhanced muscle mass at day 28 postinjury. BS encapsulated hPDSCs cultured under normoxic or hypoxic conditions increased small myofibers (<500 µm2) percentage, MyoD protein expression, and both pro- and anti-inflammatory macrophage marker expression. BS encapsulated hPDSCs also reduced fibrosis and BS remodeling rate. Innovation: This study is the first to examine the therapeutic effects of hPDSCs in a rat VML model. A BS carrier and hypoxic preconditioning were investigated to mitigate low cell survival postimplantation. Conclusion: hPDSCs augment the regenerative effect of BS. Combining hPDSCs and BS emerges as a promising strategy worthy of further investigation.

A comparative study of pathogen inactivation technologies in human platelet lysate and its optimal efficiency in human placenta-derived stem cells culture

BackgroundPathogen inactivation (PI) is necessary for the pooled components derived from a biological source. Recently, the use of human platelet lysate (hPL) has increased in the cell manufacturing process as a xeno-free substitute for Fetal Bovine Serum (FBS). Therefore, an effective PI process to produce a pathogen-free hPL with the optimal efficiency in the manufacturing of cell therapy products is a vital requirement. Study design and methodsTo evaluate the efficacy of gamma irradiation and riboflavin/ultraviolet light (RB/UV) as PI methods for hPL, the reduction factor (RF) of titer of model viruses and bacteria were examined. Furthermore, the effect of different PI methods on the hPL performance was evaluated by the in vitro expansion of human placenta-derived mesenchymal stem cells (PLMSCs). To compare different study groups, the growth kinetic, immunophenotype, colony formation, and differentiation capacity (osteogenic and adipogenic) of PLMSCs were examined. In addition, the concentration of growth factors was assayed in each study group. ResultsAchievement to the RF more than 5 log10 for all pathogens, showed the effectiveness of two PI methods. In comparison with the other study groups, the dose of 45 kGy gamma irradiation considerably decreased the growth factor level of the hPL. It also showed a significant adverse effect on PLMSCs growth kinetics. The dose of 30 KGy gamma irradiation and RB/UV demonstrated a favorable effect on different assays of the in vitro expanded PLMSCs. ConclusionThe 30 KGy gamma irradiation and RB/UV were effective in the RF of the viral and bacterial models of the contaminated hPL. The efficacy of these PI-hPLs for PLMSCs expansion was preserved. To increase the safety of cell therapy products, PI methods should be considered for the hPL preparations.

Human placenta-derived stem cells - recent findings based on the molecular science

Abstract The human placenta is a complex, multifunctional transient fetomaternal organ. The placenta is composed of the maternal decidua basalis and its fetal part, consisting of the mesenchymal and trophoblast cell lineages. Both the placenta and the amniotic membranes are abundant in readily available placenta-derived mesenchymal stem cells (PD-MSCs). The clinical application of the PD-MSCs opens new perspectives for regenerative medicine and the treatment of various degenerative disorders. Their properties depend on their paracrine activity – the secretion of the anti-inflammatory cytokines and specific exosomes. In contrast to the PD-MSCs, the trophoblast stem cells (TSCs) are much more elusive. They can only be isolated from the blastocyst-stage embryos or the first-trimester placental tissue, making that procedure quite demanding. Also, other cultures require specific, strictly controlled conditions. TSCs may be potentially used as an in vitro model of various placental pathologies, facilitating the elucidation of their mysterious pathogenesis and creating the environment for testing the new drug efficiency. Nonetheless, it is unlikely that they could be ever implemented as a part of novel cellular therapeutic strategies in humans. Running title: Current knowledge on the placental stem cells

Hypoxia-Preconditioned Placenta-Derived Mesenchymal Stem Cells Rescue Optic Nerve Axons Via Differential Roles of Vascular Endothelial Growth Factor in an Optic Nerve Compression Animal Model

Human placenta-derived stem cells (hPSCs) with the therapeutic potential to recover from optic nerve injury have been reported. We have recently demonstrated that hPSCs have protective abilities against hypoxic damage. To improve the capacity of hPSCs, we established a hypoxia-preconditioned strain (HPPCs) using a hypoxic chamber. The hPSCs were exposed to short-term hypoxic conditions of 2.2% O2 and 5.5% CO2. We also performed in vivo experiments to demonstrate the recovery effects of HPPCs using an optic nerve injury rat model. Naïve hPSCs (and HPPCs) were injected into the optic nerve. After 1, 2, or 4weeks, we analyzed changes in target proteins in the optic nerve tissues. In the retina, GAP43 expression was higher in both groups of naïve hPSCs and HPPCs versus sham controls. Two weeks after injection, all hPSC-injected groups showed recovery of tuj1 expression in damaged retinas. We also determined GFAP expression in retinas using the same model. In optic nerve tissues, HIF-1α levels were significantly lower in the HPPC-injected group 1week after injury, and Thy-1 levels were higher in the hPSC-injected group at 4weeks. There was also an enhanced recovery of Thy-1 expression after HPPC injection. In addition, R28 cells exposed to hypoxic conditions showed improved viability through enhanced recovery of HPPCs than naïve hPSCs. VEGF protein was a mediator in the recovery pathway via upregulation of target proteins regulated by HPPCs. Our results suggest that HPPCs may be candidates for cell therapy for the treatment of traumatic optic nerve injury.

Dynamic Changes in Erectile Function and Histological Architecture After Intracorporal Injection of Human Placental Stem Cells in a Pelvic Neurovascular Injury Rat Model

IntroductionThe human placenta provides a bountiful and noncontroversial source of stem cells which have the potential for regeneration of injured tissue. These cells may restore erectile function after neurovascular tissue injury such as that seen in radical pelvic surgeries and pelvic trauma. AimTo determine the effect of human placenta–derived stem cells on erectile function recovery and histological changes at various time points in a cavernous nerve injury rat model and to study the fate of injected stem cells throughout the regenerative process. MethodsHuman placental stem cells (PSCs) were dual labeled with monomeric Katushka far red fluorescent protein (mKATE)-renLUC using a lentivirus vector. A pelvic neurovascular injury–induced erectile dysfunction model was established in male, athymic rats by crushing the cavernous nerves and ligating the internal pudendal neurovascular bundles, bilaterally. At the time of defect creation, nonlabeled PSCs were injected into the corpus cavernosum at a concentration of 2.5 × 106 cells/0.2 mL. The phosphate-buffered saline–treated group served as the negative control group, and age-matched rats (age-matched controls) were used as the control group. Erectile function, histomorphological analyses, and Western blot were assessed at 1, 6, and 12 weeks after model creation. The distribution of implanted, dual-labeled PSCs was monitored using an in vivo imaging system (IVIS). Implanted cells were further tracked by detection of mKATE fluorescence in histological sections. Main Outcome MeasureThe main outcome measure includes intracavernous pressure/mean arterial pressure ratio, neural, endothelial, smooth muscle cell regeneration, mKATE fluorescence, and IVIS imaging. ResultsThe ratio of intracavernous pressure to mean arterial pressure significantly increased in PSC-injected rats compared with phosphate-buffered saline controls (P < 0.05) at the 6- and 12-week time points, reaching 72% and 68% of the age-matched control group, respectively. Immunofluorescence staining and Western blot analysis showed significant increases in markers of neurons (84.3%), endothelial cells (70.2%), and smooth muscle cells (70.3%) by 6 weeks in treatment groups compared with negative controls. These results were maintained through 12 weeks. IVIS analysis showed luminescence of implanted PSCs in the injected corpora immediately after injection and migration of cells to the sites of injury, including the incision site and periprostatic vasculature by day 1. mKATE fluorescence data revealed the presence of PSCs in the penile corpora and major pelvic ganglion at 1 and 3 days postoperatively. At 7 days, immunofluorescence of penile PSCs had disappeared and was diminished in the major pelvic ganglion. Clinical ImplicationsPlacenta-derived stem cells may represent a future “off-the-shelf” treatment to mitigate against development of erectile dysfunction after radical prostatectomy or other forms of pelvic injury. Strength & LimitationsSingle dose injection of PSCs after injury resulted in maximal functional recovery and tissue regeneration at 6 weeks, and the results were maintained through 12 weeks. Strategies to optimize adult stem cell therapy might achieve more effective outcomes for human clinical trials. ConclusionHuman PSC therapy effectively restores the erectile tissue and function in this animal model. Thus, PSC therapy may provide an attractive modality to lessen the incidence of erectile dysfunction after pelvic neurovascular injury. Further improvement in tissue regeneration and functional recovery may be possible using multiple injections or systemic introduction of stem cells.Gu X, Thakker PU, Matz EL, et al. Dynamic Changes in Erectile Function and Histological Architecture After Intracorporal Injection of Human Placental Stem Cells in a Pelvic Neurovascular Injury Rat Model. J Sex Med 2020;17:400–411.

Allogeneic Hematopoietic Stem Cell Transplantation (Allo-HSCT) with Human Placenta-Derived Stem Cells (HPDSC) Combined with Unrelated Cord Blood (UCB) for Malignant and Non-Malignant Disorders (IND 14949)

Background MAC or RTC followed by UCB donor allo-HSCT in children with malignant and non-malignant diseases is safe and effective (Geyer/Cairo, BJH 2011). However, concentration of CD34+ HPCs in UCB is low, leading to delayed hematopoietic reconstitution and high incidence of engraftment failure (Satwani/Cairo, BBMT 2013). HPDSCs are rich in HPCs, low in HLA Class I/II expression and T-cells, and have regenerative, anti-inflammatory, and immunosuppressive properties (Liao/Cairo, Stem Cells Trans Med 2018). Objective To determine the safety and efficacy of HPDSCs plus UCB for allo-HSCT in children. Design/Method UCB with TNC ≥ 5 × 107/kg (4/6 HLA match) or ≥ 3.5 × 107/kg (5-6/6 HLA match) were included. Patients received MAC or RTC followed by UCB plus HPDSC infusion. GVHD prophylaxis consisted of tacrolimus and MMF as previously described (Bhatia/Cairo, BBMT 2009). Results Twenty-eight patients ≤18 years were enrolled, 15 males. Mean age± SD was 6.8±5.5 years, (4 months-12 years). There were 12 patients with non-malignant diseases including ALD (2), CAT (1), CGD (1), SCID (2), DC (1), CN (1), SAA (2), LCH (1), and SDS (1) and 16 patients with malignant diseases including B-ALL- CR1 (4), B-ALL - CR2 (4), T-ALL – CR1 (1), AML-CR1 (4), JMML-CR1 (1), TLL - CR1 (1), and BL - CR2 (1). There were 13, 9, and 5 patients with 6/6, 5/6, and 4/6 HLA match, respectively. Mean UCB TNC±SD and CD34+ cell dose±SD infused were 0.77±0.5 × 108/kg and 0.48±0.59 × 106/kg, respectively. Mean HPDSC TNC±SD and CD34+ cell±SD dose were 0.96±3.51 × 108/kg and 0.05±0.05 × 106/kg, respectively. There were no SAEs associated with HPDSC infusions. Four patients were withdrawn for administration of alternative therapy after engraftment failure (3) or relapse (1). Probability of neutrophil engraftment by day 42 was 78.6%, median day 22 (13-53). Probability of platelet engraftment by day 100 in neutrophil engrafted patients was 86.4%, median day 42 (35-98) (Figure 1). Mean UCB chimerism was 92, 99, 96 and 99% at day 30, 60, 100 and 180, respectively. Average HPDSC chimerism was Conclusions These results suggest that UCB plus HPDSCs for Allo-HSCT is safe and well tolerated. Median day to platelet engraftment was lower than previously reported using UCB alone (Geyer/Cairo.BJH 2011). Probability of Grade 2-4 aGVHD was lower than previously reported using UCB alone, possibly due to the immunomodulatory effect of HPDSCs (Geyer/Cairo.BJH 2011). A larger cohort and longer follow-up is required to determine clinical significance.

Hematopoietic Stem Cell Transplantation with Human Placenta-Derived Stem Cells Combined with Unrelated Cord Blood for Malignant and Non-Malignant Disorders (IND 14949)

Background Myeloablative (MAC) or reduced toxicity conditioning (RTC) followed by UCBT in children with malignant and non-malignant diseases is safe and effective (Geyer/Cairo, BJH 2011). However, concentration of CD34+ HPCs in UCB is low, leading to delayed hematopoietic reconstitution and high incidence of engraftment failure (Satwani/Cairo, BBMT 2013). HPDSCs are rich in HPCs, low in HLA Class I/II expression and T-cells, and have regenerative, anti-inflammatory, and immunosuppressive properties (Liao/Cairo, Stem Cells Translational Medicine 2018). Objective To determine the safety and efficacy of HPDSC with UCBT in children with malignant and non-malignant diseases. Design/Method 4-6/6 HLA matched UCB with TNC ≥ 5 × 107/kg (4/6 HLA match) or ≥ 3.5 × 107/kg (5-6/6 HLA match) were included. Patients received MAC or RTC followed by UCB plus HPDSC infusion. GVHD prophylaxis consisted of tacrolimus and mycophenolate mofetil as previously described (Bhatia/Cairo, BBMT 2009). Results To date, 28 patients ≤18 years were enrolled, 15 males and 13 females. Mean age in years ± SD was 6.8±5.5. There were 12 patients with non-malignant disease including ALD (2), CAT (1), CGD (1), SCID (2), dyskeratosis congenita (1), congenital neutropenia (1), SAA (2), LCH (1), and SDS (1) and 16 patients with malignant disease including pre B-cell ALL- CR1 (4), pre B-cell ALL - CR2 (4), T-cell ALL – CR1 (1), AML-CR1 (4), JMML-CR1 (1), TLL - CR1 (1), and BL - CR2 (1). Mean UCB TNC±SD and CD34±SD infused were 7.7 × 107±5.0/kg and 0.48 × 106±0.59/kg, respectively. There were no SAEs associated with HPDSC infusions. Four patients were removed prior to day 180 due to progressive disease (1) and engraftment failure necessitating alternative treatment (3). Probability of neutrophil engraftment was 89.2%, median day 22 (13-53). Of neutrophil engrafted evaluable patients (n=22), the probability of platelet engraftment by day 100 was 90.9%, median day 42 (20-98). Of neutrophil engrafted, evaluable patients at day 30, 60, 100 and 180, mean whole blood UCB chimerism was 92, 99, 96 and 99%, respectively. Average whole blood HPDSC chimerism was Conclusions These results suggest that UCBT with HPDSC is safe and well tolerated, has a lower than expected probability of Grade 2-4 aGVHD, and results in robust immune reconstitution. A larger cohort and longer follow-up is required to determine the clinical significance of these findings.

Immunomodulatory effect of CD200-positive human placenta-derived stem cells in the early phase of stroke

Human placenta amniotic membrane-derived mesenchymal stem cells (AMSCs) regulate immune responses, and this property can be exploited to treat stroke patients via cell therapy. We investigated the expression profile of AMSCs cultured under hypoxic conditions and observed interesting expression changes in various genes involved in immune regulation. CD200, an anti-inflammatory factor and positive regulator of TGF-β, was more highly expressed under hypoxic conditions than normoxic conditions. Furthermore, AMSCs exhibited inhibition of pro-inflammatory cytokine expression in co-cultures with LPS-primed BV2 microglia, and this effect was decreased in CD200-silenced AMSCs. The AMSCs transplanted into the ischemic rat model of stroke dramatically inhibited the expression of pro-inflammatory cytokines and up-regulated CD200, as compared with the levels in the sham-treated group. Moreover, decreased microglia activation in the boundary region and improvements in behavior were confirmed in AMSC-treated ischemic rats. The results suggested that the highly expressed CD200 from the AMSCs in a hypoxic environment modulates levels of inflammatory cytokines and microglial activation, thus increasing the therapeutic recovery potential after hypoxic-ischemic brain injury, and further demonstrated the immunomodulatory function of AMSCs in a stroke model.

CD34- human placenta-derived mesenchymal stem cells protect against heat stroke mortality in rats.

CD34 is a transmembrane phosphoglycoprotein used to selectively enrich bone marrow in hematopoietic stem cells for transplantation. Treating rats with CD34+ cells derived from human umbilical cord blood before or after heat stroke has been shown to promote survival. We investigated whether CD34– human placenta-derived stem cells (PDMSCs) could improve survival following heat stroke in rats. Rats were subjected to heat stress (42°C for 98 min) to induce heat stroke. Intravenous administration of PDMSCs 1 day before or immediately after the onset of heat stroke improved survival by 60% and 20%, respectively. Pre-treatment with CD34− PDMSCs protected against heat stroke injury more effectively than that treatment after injury. PDMSCs treatment attenuated cerebrovascular dysfunction, the inflammatory response, and lipid peroxidation. These data suggest human PDMSCs protect against heat stroke injury in rats. Moreover, these effects do not require the presence of CD34+ cells.

Real-time regulatory effects of IFN-γ and programed death ligand 2 (PDL2) on adherence, proliferation and migration of human placenta-derived mesenchymal stem cells

Objective To investigate the real-time regulatory effects of IFN-γ, programed death ligand 2(PDL2) and janus kinase/signal transducers and activators of transcription (JAK/STAT) signaling pathway on the adherence, proliferation and migration of human placenta-derived mesenchymal stem cells(hPMSCs) based on a finding that IFN-γ could enhance the expression of PDL2 in hPMSCs through JAK/STAT signaling pathway. Methods hPMSCs were isolated by using enzyme digestion method and then co-cultured with IFN-γ, anti-PDL2 monoclonal antibody (anti-PDL2 McAb) and JAK inhibitor, respectively. Real-time cell analysis (RTCA) was used to detect the dynamic changes in the adherence, proliferation and migration of hPMSCs following various interventions. Results IFN-γ remarkably suppressed hPMSCs proliferation during the period from 40 hours to 80 hours after intervention and also inhibited the non-targeted migration of hPMSCs. However, hPMSCs adherence was not affected by IFN-γ. Co-culturing hPMSCs with anti-PDL2 McAb significantly enhanced hPMSCs adhesion and inhibited their non-targeted migration, but had no significant effect on hPMSCs proliferation. Furthermore, the proliferation of hPMSCs co-cultured with IFN-γ and anti-PDL2 McAb was significantly inhibited as compared with that of anti-PDL2McAb treatment group. The adhesion, migration and proliferation of hPMSCs were significantly inhibited after co-culturing them with JAK inhibitor. Conclusion IFN-γ can remarkably suppress the proliferation and migration of hPMSCs. PDL2 can enhance the migration and inhibit the adhesion of hPMSCs. JAK/STAT signaling pathway is involved in regulating the adhesion, migration and proliferation of hPMSCs. Key words: IFN-γ; Mesenchymal stem cell; Adherence; Proliferation; Migration; PDL2

134 - A Pilot Trial of Unrelated Donor Human Placenta-Derived Stem Cells (HPDSC) in Conjunction with Single Unrelated Cord Blood Transplantation (UCBT) in Children with Malignant and Non-Malignant Disease (IND 14949)

134 - A Pilot Trial of Unrelated Donor Human Placenta-Derived Stem Cells (HPDSC) in Conjunction with Single Unrelated Cord Blood Transplantation (UCBT) in Children with Malignant and Non-Malignant Disease (IND 14949)

A Pilot Trial of Unmatched Human Placenta-Derived Stem Cells (HPDSCs) in Conjunction with Unrelated Cord Blood Transplantation (UCBT) in Children and Young Adults with Malignant and Non-Malignant Disease (IND 14949)

Background: Myeloablative conditioning (MAC) and reduced toxicity conditioning (RTC) followed by UCBT (matched at 4-6/6 HLA loci) in children with malignant and non-malignant diseases is safe and effective (Wagner/Cairo et al, Blood, 1996; Geyer/Cairo et al, BJH, 2011). However, there is a low concentration of CD34+ hematopoietic progenitor cells (HPCs) in banked UCB (Cairo/Kurtzberg et al, Transfusion, 2005) compared to bone marrow or peripheral blood, leading to delayed hematopoietic reconstitution and 10-20% incidence of graft failure (Cairo et al, Blood, 1997; Cairo et al, Transfusion, 2005; Satwani/Cairo et al, BBMT, 2013). Human placenta-derived stem cells (HPDSCs) are rich in HPCs and HPC colony forming unit capabilities, low in HLA Class I and II expression, low in T-cell content, and have regenerative, anti-inflammatory, and immunosuppressive properties (Cairo et al, BMT, 2015). Mendez-Ferrer et al have demonstrated that HPDSCs enhance in-vivo engraftment when combined with UCBT in NOD-SCID animals (Mendez-Ferrero et al, Nature, 2010).Objective: To determine the safety of administering unrelated donor HPDSC in conjunction with unrelated single or double UCBT following MAC or RTC in children and adults with malignant and non-malignant diseases and to determine the time to hematopoietic engraftment, immune reconstitution and probability of donor chimerism.Methods: Patients ≤55 years of age with malignant and non-malignant diseases with a single UCB 5-6/6 HLA match and TNC ≥ 3.5x 107/kg, or double UCB 4-6/6 HLA match and combined TNC >5.0 x 107/kg are eligible. HLA typing was performed by serology for Class I A and B and by high resolution DNA typing of DRB1. Patients received either fully myeloablative or reduced toxicity pre-UCBT conditioning as indicated for the targeted disease followed by single or double UCB plus HPDSC infusion. All patients received filgrastim (G-CSF) starting at least 24 hours after the HPDSC infusion until myeloid engraftment and GVHD prophylaxis with tacrolimus or cyclosporine plus mycophenolate mofetil.Results: Twenty one patients have been enrolled to date: mean age 11 (0.31-34.9) years, 11 males, 10 females. Fourteen subjects had malignancies (relapsed/refractory or hypodiploid precursor B-ALL (n=7), relapsed/refractory or high risk AML (n=5), T-cell ALL induction failure (n=1), and T-cell lymphoblastic lymphoma (n=1)) and seven had non-malignant disorders (adrenoleukodystrophy (n=1), chronic granulomatous disease (n=1), congenital amegakaryocytic thrombocytopenia (n=1), bone marrow failure (n=1), SCID (n=1), severe aplastic anemia (n=1), and dyskeratosis congenita (n=1)). Fourteen patients received single UCBT followed by HPDSC infusion, and seven patients received double UCBT followed by HPDSC infusion. There were no severe adverse events associated with the HPDSC infusions. Median time to neutrophil and platelet engraftment were 22 (13-53) and 45 (20-98) days post UCBT, respectively. Mean percent of whole blood donor chimerism at days 30, 60, 100 and 180 were 97% (SEM 1.25), 99%, (SEM 0.36), 99% (SEM 0.39), and 97.9 (SEM 1.31), respectively. Average percent of whole blood HPDSC chimerism was <1% at day 30. Average absolute CD3/4/8 at days 100, 180, 270, and 365 were 150/107/43, 411/ 256/154, 1020/630/371, and 1207/728/458, respectively, per mcl. Average absolute CD56 and CD19 at days 100, 180, 270 and 365 were 478/654, 190/713, 308/2225 and 361/1215 respectively. The probability of NRM at day 100 was 0%. Of patients with malignant disease, the incidence of relapse was 0/14 (0%) at day 100 and 1/14 (7.1%) at day 180 post-transplant. For the full cohort, the probability of Grade II-IV aGVHD was 14.8% (CI95 0.0-28.9) (Figure 1) and the probability of 12 month overall survival was78.6% (CI95 62.0-99.6) (Figure 2). OS at day 100 and day 180 are 19/19 (100%) and 15/19 (78.9%) respectively. 2/21 patients have not yet reached day 100. Sixteen of twenty-one patients are alive at a median of 535 (53-1175) days post UCBT.Conclusions: These preliminary results suggest that single or double UCBT combined with unrelated HPDSC is safe, well tolerated, and has a lower than expected probability of Grade II-IV aGVHD. A larger cohort and longer follow-up is required to determine the safety and clinical significance of these early findings. [Display omitted] [Display omitted] DisclosuresPulsipher:Novartis: Consultancy, Other: Study Steering Committee; Jazz Pharmaceutical: Consultancy; Chimerix: Consultancy; Medac: Other: Housing support for conference. Zhang:Celgene: Employment, Equity Ownership, Patents & Royalties. Gurney:Celgene: Employment, Equity Ownership. Cairo:Celgene: Research Funding.

Conditioned medium of H9c2 triggers VEGF dependent angiogenesis by activation of p38/pSTAT3 pathways in placenta derived stem cells for cardiac repair

AimsCardiomyocytes are understood to possess a limited regenerative capacity. Any myocardial insult leads to an irreversible injury. Mesenchymal stem cell differentiation into cardiomyocyte-like cells stands as one of the leading experimental therapies. However, a candidate cell source has yet to be defined. Here, we examined the in vitro and in vivo cardiac differentiation potential of human placenta derived stem cells (hPDSCs); a unique, abundant, and non-immunogenic cell source. Main methodsH9c2 cell culture medium was applied to hPDSCs at different ratios for a period of 4weeks. In parallel, hPDSCs, human bone marrow stem cells, or cell free culture medium was injected in peri-infarcted regions induced in rat hearts. Key findingsIn vitro, hPDSCs pre-conditioned with H9c2 cell culture medium proportionally over-expressed alpha sarcoplasmic actinin and displaced connexin 43 from the cytoplasm to the cell membrane. Additionally, pre-conditioning promoted hPDSCs survival and triggered vascular endothelial growth factor (VEGF) dependent angiogenesis by activating the pAkt and p38MAPK/pSTAT3 pathways. In vivo, echocardiography analysis showed a significant improvement in cardiac parameters in the rats injected with hPDSCs, similar to the human bone marrow stem cells injected group. Moreover, hPDSCs detected within rat cardiac tissues expressed troponin I and myosin heavy chain. In accordance with the pre-conditioning findings, VEGF positive neovessels were observed in hearts injected with hPDSCs. SignificancehPDSCs have the potential to differentiate into cardiac-like cells and induce angiogenesis via paracrine effects. With the advantages of easy availability and young age, these cells could be more suitable for clinical translation.

A Rational Strategy for the Use of Amniotic Epithelial Stem Cell Therapy for Liver Diseases.

Stem cell-based therapies hold the potential to alleviate the burden of many serious diseases, including those of the liver. Among the different types of stem cells, human placenta-derived stem cells are potentially one of the most clinically applicable stem cells because of their tissue-specific advantages. They are a readily available cell source that can be procured in a noninvasive manner, and there are few ethical concerns regarding their use. Recent studies have demonstrated that the amniotic epithelium contains stem cells that possess four unique and advantageous properties; human amniotic epithelial cells (hAECs) have low immunogenicity, secrete several immune regulatory molecules, possess the potential to differentiate into all three germ layers, and contain abundant lysosomes allowing them to secrete lysosomal enzymes. This perspective article provides an overview of the beneficial properties of hAECs and proposes a rational strategy for translating placental stem cells toward clinical application for various liver diseases. This article provides an overview of the beneficial properties of one type of human placental stem cell and proposes a rational strategy for translating placental stem cells toward clinical application for various liver diseases.

Potential Use of Human Placenta Derived Stem Cell (HPDSCs) As a Novel Stem Cell Source for the Treatment of Recessive Dystrophic Epidermolysis Bullosa (RDEB)

Potential Use of Human Placenta Derived Stem Cell (HPDSCs) As a Novel Stem Cell Source for the Treatment of Recessive Dystrophic Epidermolysis Bullosa (RDEB)

Isolation and Identification of Human Umbilical Cord and Placenta-derived Stem Cells and Their Component Analysis

Clinical transplantation evidence has been indicated that umbilical cord blood (UCB) can be useful in the hematopoietic reconstitution in the children, but can not be well in the adult hematopoietic transplantation because of the low count. This study was to evaluate a new method for collecting stem cells from human placenta and umbilical cord, and to comparatively analyze the similarity and difference of quality and quantity of the cells. The UCB was collected, in same time the placental tissue was sterily collected; the umbilical placenta was collected by perfusing the blood (UPB) cord arterial and venous vascules with 0.9% saline; the mesenchymal stem cells (MSC) from same source of umbilical cord and placental tissues were isolated and cultured. The cell colony assay and flow cytometry were performed to determine the proliferation capacities and cell markers of UMSC and PMSC. The total nuclear cells (NC) and hematopoietic stem cells (CD34(+)) from UPB and UCB were (17.45 ± 16.86) × 10(8), (6.9 ± 4.61) × 10(8) and (2.97 ± 2.25) × 10(6), (1.91 ± 1.7) × 10(6), respectively. Furthermore, the UPB contained more early precursor of hematopoietic stem cells (CD33(+) CD34(-)) (6.2 ± 13.5) × 10(5), (0.2 ± 0.8) × 10(5) ; and high proportion of MSC to NC (25.21 ± 18.69, 0.05 ± 0.10)%, respectively in 62 samples. There were no difference of the MSC level in UPB and UCB, as well as in the morphology and cell markers. UPB has rich hematopoietic stem cells and mesenchymal stem cells. Placenta may offer another source for hematopoietic stem cells in research of hematopoietic stem cells and regeneration medicine.

Cellular engineering and therapy in combination with cord blood allografting in pediatric recipients.

Cord blood (CB) transplantation is an alternate source of human hematopoietic progenitor cells for allogeneic stem cell transplantation in children and adolescents with both malignant and nonmalignant diseases. Current limitations included delay in hematopoietic reconstitution, increased incidence of primary graft failure and slow cellular immunoreconstitution. These limitations lead to a significant increase in primary graft failure, infectious complications and increased transplant-related mortality. There is a number of experimental approaches currently under investigation including cellular engineering to circumvent these limitations. In this review, we summarize the recent findings of utilizing ex vivo CB expansion with Notch1 ligand Delta 1, mesenchymal progenitor cells, the use of human placenta-derived stem cells and CB-derived natural killer cells. Early and preliminary results suggest some of these experimental cellular strategies may in part ameliorate the incidence of primary graft failure, delays in hematopoietic reconstitution and/or slowness in cellular immune reconstitution following unrelated CB transplantation.

Transplantation of human placenta-derived multipotent stem cells reduces ischemic brain injury in adult rats.

After the onset of stroke, a series of progressive and degenerative reactions, including inflammation, is activated, which leads to cell death. We recently reported that human placenta-derived multipotent stem cells (hPDMCs) process potent anti-inflammatory effects. In this study, we examined the protective effect of hPDMC transplants in a rodent model of stroke. Adult male Sprague-Dawley rats were anesthetized. hPDMCs labeled with a vital dye of fluorescing microparticles, DiI, or vehicle were transplanted into three cortical areas adjacent to the right middle cerebral artery (MCA). Five minutes after grafting, the right MCA was transiently occluded for 60 min. Stroke animals receiving hPDMCs showed a significant behavioral improvement and reduction in lesion volume examined by T2-weighted images 4 days poststroke. Brain tissues were collected 1 day later. Human-specific marker HuNu immunoreactivity and DiI fluorescence were found at the hPDMC graft sites, suggesting the survival of hPDMCs in host brain. Grafting of hPDMCs suppressed IBA1 immunoreactivity and deramification of IBA1(+) cells in the perilesioned area, suggesting activation of microglia was attenuated by the transplants. Taken together, our data indicate that hPDMC transplantation reduced cortical lesions and behavioral deficits in adult stroke rats, and these cells could serve as a unique anti-inflammatory reservoir for the treatment of ischemic brain injury.

In Vitro Differentiation Potential of Human Placenta Derived Cells into Skin Cells.

Skin autografting is the most viable and aesthetic technique for treatment of extensive burns; however, this practice has potential limitations. Harvesting cells from neonatal sources (such as placental tissue) is a simple, inexpensive, and noninvasive procedure. In the current study authors sought to evaluate in vitro potential of human placenta derived stem cells to develop into skin-like cells. After extensive washing, amniotic membrane and umbilical cord tissue were separated to harvest amniotic epithelial cells (AECs) and umbilical cord mesenchymal stem cells (UC-MSCs), respectively. Both types of cells were characterized for the expression of embryonic lineage markers and their growth characteristics were determined. AECs and UC-MSCs were induced to differentiate into keratinocytes-like and dermal fibroblasts-like cells, respectively. After induction, morphological changes were detected by microscopy. The differentiation potential was further assessed using immunostaining and RT-PCR analyses. AECs were positive for cytokeratins and E-Cadherin while UC-MSCs were positive for fibroblast specific makers. AECs differentiated into keratinocytes-like cells showed positive expression of keratinocyte specific cytokeratins, involucrin, and loricrin. UC-MSCs differentiated into dermal fibroblast-like cells indicated expression of collagen type 3, desmin, FGF-7, fibroblast activation protein alpha, procollagen-1, and vimentin. In conclusion, placenta is a potential source of cells to develop into skin-like cells.

Characterization and ex vivo Expansion of Human Placenta-Derived Natural Killer Cells for Cancer Immunotherapy

Recent clinical studies suggest that adoptive transfer of donor-derived natural killer (NK) cells may improve clinical outcome in hematological malignancies and some solid tumors by direct anti-tumor effects as well as by reduction of graft versus host disease (GVHD). NK cells have also been shown to enhance transplant engraftment during allogeneic hematopoietic stem cell transplantation (HSCT) for hematological malignancies. The limited ex vivo expansion potential of NK cells from peripheral blood (PB) or umbilical cord blood (UCB) has however restricted their therapeutic potential. Here we define methods to efficiently generate NK cells from donor-matched, full-term human placenta perfusate (termed Human Placenta-Derived Stem Cell, HPDSC) and UCB. Following isolation from cryopreserved donor-matched HPDSC and UCB units, CD56+CD3− placenta-derived NK cells, termed pNK cells, were expanded in culture for up to 3 weeks to yield an average of 1.2 billion cells per donor that were >80% CD56+CD3−, comparable to doses previously utilized in clinical applications. Ex vivo-expanded pNK cells exhibited a marked increase in anti-tumor cytolytic activity coinciding with the significantly increased expression of NKG2D, NKp46, and NKp44 (p < 0.001, p < 0.001, and p < 0.05, respectively). Strong cytolytic activity was observed against a wide range of tumor cell lines in vitro. pNK cells display a distinct microRNA (miRNA) expression profile, immunophenotype, and greater anti-tumor capacity in vitro compared to PB NK cells used in recent clinical trials. With further development, pNK may represent a novel and effective cellular immunotherapy for patients with high clinical needs and few other therapeutic options.