Amnion-derived cells as a reliable resource for next-generation regenerative medicine

Exosomes secreted from amniotic mesenchymal stem cells modify trophoblast activities by delivering miR-18a-5p and regulating HRK-p53 interaction

BACKGROUND

Amniotic mesenchymal stem cells (AMSCs) have been demonstrated as effective in tissue repair and regeneration. Trophoblast dysfunction is associated with several types of pregnancy complications. The aim of this study is to investigate the effects of AMSCs on the biological activities of human trophoblasts, as well as their molecular mechanisms.

METHODS

Exosomes were isolated from AMSC supernatants, and characterized and quantified by transmission electron microscopy, nanoparticle tracking analysis and Western blotting assay. Immunofluorescence assay was performed to detect the uptake of AMSCs-derived exomes (AMSC-Exos) by human trophoblasts. Human trophoblasts were subjected to transcriptome analysis after being cocultured with AMSC-Exos. Lentiviral transfection was performed to construct the human trophoblast cell lines with stable HRK knockdown or overexpression. Immunohistochemistry was used to detect the HRK expression in preeclampsia (PE) patients. CCK8 and Transwell assays were, respectively, used to detect the trophoblast proliferation and migration. TUNEL flow cytometry assay was used to detect the apoptosis in trophoblasts. Quantitative real-time (qRT) PCR and Western blotting assays were used to detect the mRNA and protein levels of the genes. Dual luciferase reporter assays were used to detect the changes in gene-transcript levels.

RESULTS

AMSC-Exos could be absorbed by human trophoblasts. Transcriptome analysis showed that HRK was significantly reduced in human trophoblasts cocultured with AMSC-Exos. HRK inhibited cell proliferation and migration in human trophoblasts and promoted their apoptosis via p53 upregulation. miR-18a-5p, present at high levels in AMSC-Exos, improved trophoblast proliferation and migration, and inhibited their apoptosis by inhibiting the HRK expression.

CONCLUSION

miR-18a-5p present in AMSC-Exos could be absorbed by trophoblasts, in turn, improved their proliferation and migration, and inhibited their apoptosis by HRK downregulation.

Effects of human amniotic membrane on the angiogenesis and healing of ischemic wounds in a rat model

Although the human amniotic membrane (hAM) has been demonstrated to promote angiogenesis, its efficacy in healing ischemic wounds remains unknown. Therefore, the current study aimed to evaluate the potential of hAM as a dressing for treating ischemic wounds. The inferior abdominal wall arteries and veins of male rats were divided, and an ischemic wound was created on each side of the abdominal wall. Of the two ischemic wounds created, only one was covered with hAM, and its wound healing effect was determined by measuring the wound area. Angiogenesis was assessed by measuring microvessel density (MVD). On day 5, the mean wound area changed from 400 mm2 to 335.4 (260-450) mm2 in the hAM group and to 459 (306-570) mm2 in the control group (p = 0.0051). MVD was 19.0 (10.4-24.6) in the hAM group and 15.1 (10.6-20.8) in the control group (p = 0.0026). No significant differences in local pro- and anti-inflammatory cytokine levels were observed between the two groups. Histological examination revealed no rejection of the transplanted hAM. Therefore, the hAM may serve as a novel wound dressing that can promote angiogenesis and healing in ischemic wounds.

Optimization of a nanoparticle uptake protocol applied to amniotic-derived cells: unlocking the therapeutic potential

Stem cell-based therapy implementation relies heavily on advancements in cell tracking. The present research has been designed to develop a gold nanorod (AuNR) labeling protocol applied to amniotic epithelial cells (AECs) leveraging the pro-regenerative properties of this placental stem cell source which is widely used for both human and veterinary biomedical regenerative applications, although not yet exploited with tracking technologies. Ovine AECs, in native or induced mesenchymal (mAECs) phenotypes via epithelial-mesenchymal transition (EMT), served as the model. Initially, various uptake methods validated on other sources of mesenchymal stromal cells (MSCs) were assessed on mAECs before optimization for AECs. Furthermore, the protocol was implemented by adopting the biological strategy of MitoCeption to improve endocytosis. The results indicate that the most efficient, affordable, and easy protocol leading to internalization of AuNRs in living mAECs recognized the combination of the one-step uptake condition (cell in suspension), centrifugation-mediated internalization method (G-force) and MitoCeption (mitochondrial isolated from mAECs). This protocol produced labeled vital mAECs within minutes, suitable for preclinical and clinical trials. The optimized protocol has the potential to yield feasible labeled amniotic-derived cells for biomedical purposes: up to 10 million starting from a single amniotic membrane. Similar and even higher efficiency was found when the protocol was applied to ovine and human AECs, thereby demonstrating the transferability of the method to cells of different phenotypes and species-specificity, hence validating its great potential for the development of improved biomedical applications in cell-based therapy and diagnostic imaging.

Amniotic miracle: Investigating the unique development and applications of amniotic membrane in wound healing

BACKGROUND

The perfect repair of damaged skin has always been a constant goal for scientists; however, the repair and reconstruction of skin is still a major problem and challenge in injury and burns medicine. Human amniotic membrane (hAM), with its good mechanical properties and anti-inflammatory, antioxidant and antimicrobial benefits, containing growth factors that promote wound healing, has evolved over the last few decades from simple skin sheets to high-tech dressings, such as being made into nanocomposites, hydrogels, powders, and electrostatically spun scaffolds. This paper aims to explore the historical development, applications, trends, and research hotspots of hAM in wound healing.

METHODS

We examined 2660 publications indexed in the Web of Science Core Collection (WoSCC) from January 1, 1975 to July 12, 2023. Utilizing bibliometric methods, we employed VOSviewer, CiteSpace, and R-bibliometrix to characterize general information, identify development trends, and highlight research hotspots. Subsequently, we identified a collection of high-quality English articles focusing on the roles of human amniotic epithelial stem cells (hAESCs), human amniotic mesenchymal stem cells (hAMSCs), and amniotic membrane (AM) scaffolds in regenerative medicine and tissue engineering.

RESULTS

Bibliometric analysis identified Udice-French Research Universities as the most productive affiliation and Tseng S.C.G. as the most prolific author. Keyword analysis, historical direct quotations network, and thematic analysis helped us review the historical and major themes in this field. Our examination included the knowledge structure, global status, trends, and research hotspots regarding the application of hAM in wound healing. Our findings indicate that contemporary research emphasizes the preparation and application of products derived from hAM. Notably, both hAM and the cells isolated from it - hADSCs and hAESCs are prominent and promising areas of research in regenerative medicine and tissue engineering.

CONCLUSION

This research delivers a comprehensive understanding of the knowledge frameworks, global dynamics, emerging patterns, and primary research foci in the realm of hAM applications for wound healing. The field is rapidly evolving, and our findings offer valuable insights for researchers. Future research outcomes are anticipated to be applied in clinical practice, enhancing methods for disease prevention, diagnosis, and treatment.

Human Amniotic Membrane-Derived Mesenchymal Stem Cells Prevent Acute Graft-Versus-Host Disease in an Intestinal Microbiome-Dependent Manner

Acute graft-versus-host disease (aGVHD) represents a fatal severe complication after allogeneic hematopoietic stem cell transplantation. As a promising cell therapeutic strategy of aGVHD, the mechanism of mesenchymal stem cells (MSC) to ameliorate aGVHD has not been fully clarified, especially in the field of intestinal homeostasis including the intestinal microbiome involved in the pathogenesis of aGVHD. The present study aimed to explore the effect of MSC on intestinal homeostasis including the intestinal barrier and intestinal microbiome and its metabolites, as well as the role of intestinal microbiome in the preventive process of hAMSCs ameliorating aGVHD. The preventive effects of human amniotic membrane-derived MSC (hAMSCs) was assessed in humanized aGVHD mouse models. Immunohistochemistry and RT-qPCR were used to evaluate intestinal barrier function. The 16S rRNA sequencing and targeted metabolomics assay were performed to observe the alternation of intestinal microbiome and the amounts of medium-chain fatty acids (MCFAs) and short-chain fatty acids (SCFAs), respectively. Flow cytometry was performed to analyze the frequencies of T immune cells. Through animal experiments, we found that hAMSCs had the potential to prevent aGVHD. HAMSCs could repair the damage of intestinal barrier structure and function, as well as improve the dysbiosis of intestinal microbiome induced by aGVHD, and meanwhile, upregulate the concentration of metabolites SCFAs, so as to reshape intestinal homeostasis. Gut microbiota depletion and fecal microbial transplantation confirmed the involvement of intestinal microbiome in the preventive process of hAMSCs on aGVHD. Our findings showed that hAMSCs prevented aGVHD in an intestinal microbiome-dependent manner, which might shed light on a new mechanism of hAMSCs inhibiting aGVHD and promote the development of new prophylaxis regimes for aGVHD prevention.

Effect of amniotic membrane/collagen scaffolds on laryngeal cartilage repair

Objectives

Laryngeal cartilage defects are a major problem that greatly impacts structural integrity and function. Cartilage repair is also a challenging issue. This study evaluated the efficacy of a collagen scaffold enveloped by amniotic membrane (AM/C) on laryngeal cartilage repair.

Study Design

Experimental animal study.

Methods

Fourteen Dutch rabbits were enrolled in the study. A 5 mm cartilage defect was created in the right and left thyroid lamina. The animals were divided into two groups randomly. Group 1 collagen scaffolds and group 2 AM/C were applied to the right side defects. Left side defects were not repaired, serving as control. Histologic evaluation was done 45 and 90 days following collagen and AM/C application with criteria of tissue and cell morphology, lacuna formation, vascularization, and inflammation.

Results

Significant improvement in cartilage repair was observed in the AM/C side compared to the control side in all histologic criteria after 45 days (p<.05). After 90 days, cartilage repair improved in cell morphology, lacuna formation, and inflammation significantly (p<.05).

Conclusion

The combination of amniotic membrane and collagen scaffolds provides a promising treatment modality for improving the repair of laryngeal cartilage defects.

Level of Evidence

NA.

Deciphering maternal-fetal cross-talk in the human placenta during parturition using single-cell RNA sequencing

Labor is a complex physiological process requiring a well-orchestrated dialogue between the mother and fetus. However, the cellular contributions and communications that facilitate maternal-fetal cross-talk in labor have not been fully elucidated. Here, single-cell RNA sequencing (scRNA-seq) was applied to decipher maternal-fetal signaling in the human placenta during term labor. First, a single-cell atlas of the human placenta was established, demonstrating that maternal and fetal cell types underwent changes in transcriptomic activity during labor. Cell types most affected by labor were fetal stromal and maternal decidual cells in the chorioamniotic membranes (CAMs) and maternal and fetal myeloid cells in the placenta. Cell-cell interaction analyses showed that CAM and placental cell types participated in labor-driven maternal and fetal signaling, including the collagen, C-X-C motif ligand (CXCL), tumor necrosis factor (TNF), galectin, and interleukin-6 (IL-6) pathways. Integration of scRNA-seq data with publicly available bulk transcriptomic data showed that placenta-derived scRNA-seq signatures could be monitored in the maternal circulation throughout gestation and in labor. Moreover, comparative analysis revealed that placenta-derived signatures in term labor were mirrored by those in spontaneous preterm labor and birth. Furthermore, we demonstrated that early in gestation, labor-specific, placenta-derived signatures could be detected in the circulation of women destined to undergo spontaneous preterm birth, with either intact or prelabor ruptured membranes. Collectively, our findings provide insight into the maternal-fetal cross-talk of human parturition and suggest that placenta-derived single-cell signatures can aid in the development of noninvasive biomarkers for the prediction of preterm birth.

Diverse contribution of amniogenic somatopleural cells to cardiovascular development: With special reference to thyroid vasculature

BACKGROUND

The somatopleure serves as the primordium of the amnion, an extraembryonic membrane surrounding the embryo. Recently, we have reported that amniogenic somatopleural cells (ASCs) not only form the amnion but also migrate into the embryo and differentiate into cardiomyocytes and vascular endothelial cells. However, detailed differentiation processes and final distributions of these intra-embryonic ASCs (hereafter referred to as iASCs) remain largely unknown.

RESULTS

By quail-chick chimera analysis, we here show that iASCs differentiate into various cell types including cardiomyocytes, smooth muscle cells, cardiac interstitial cells, and vascular endothelial cells. In the pharyngeal region, they distribute selectively into the thyroid gland and differentiate into vascular endothelial cells to form intra-thyroid vasculature. Explant culture experiments indicated sequential requirement of fibroblast growth factor (FGF) and vascular endothelial growth factor (VEGF) signaling for endothelial differentiation of iASCs. Single-cell transcriptome analysis further revealed heterogeneity and the presence of hemangioblast-like cell population within ASCs, with a switch from FGF to VEGF receptor gene expression.

CONCLUSION

The present study demonstrates novel roles of ASCss especially in heart and thyroid development. It will provide a novel clue for understanding the cardiovascular development of amniotes from embryological and evolutionary perspectives.

Amniotic Membrane-Derived Stromal Cells Release Extracellular Vesicles That Favor Regeneration of Dystrophic Skeletal Muscles

Duchenne muscular dystrophy (DMD) is a muscle disease caused by mutations in the dystrophin gene characterized by myofiber fragility and progressive muscle degeneration. The genetic defect results in a reduced number of self-renewing muscle stem cells (MuSCs) and an impairment of their activation and differentiation, which lead to the exhaustion of skeletal muscle regeneration potential and muscle replacement by fibrotic and fatty tissue. In this study, we focused on an unexplored strategy to improve MuSC function and to preserve their niche based on the regenerative properties of mesenchymal stromal cells from the amniotic membrane (hAMSCs), that are multipotent cells recognized to have a role in tissue repair in different disease models. We demonstrate that the hAMSC secretome (CM hAMSC) and extracellular vesicles (EVs) isolated thereof directly stimulate the in vitro proliferation and differentiation of human myoblasts and mouse MuSC from dystrophic muscles. Furthermore, we demonstrate that hAMSC secreted factors modulate the muscle stem cell niche in dystrophic-mdx-mice. Interestingly, local injection of EV hAMSC in mdx muscles correlated with an increase in the number of activated Pax7+/Ki67+ MuSCs and in new fiber formation. EV hAMSCs also significantly reduced muscle collagen deposition, thus counteracting fibrosis and MuSCs exhaustion, two hallmarks of DMD. Herein for the first time we demonstrate that CM hAMSC and EVs derived thereof promote muscle regeneration by supporting proliferation and differentiation of resident muscle stem cells. These results pave the way for the development of a novel treatment to counteract DMD progression by reducing fibrosis and enhancing myogenesis in dystrophic muscles.

The Use of Human Amniotic Membrane (hAM) as a Treatment Strategy of Medication-Related Osteonecrosis of the Jaw (MRONJ): A Systematic Review and Meta-Analysis of the Literature

Background and objectives: Although it is very uncommon, medication-induced osteonecrosis of the jaw (also known as MRONJ) can have serious consequences. Traditionally, this adverse event has been recognised in patients who were treated with bisphosphonate (BP) drugs. Nevertheless, in recent years, it has been established that individuals having treatment with various types of medications, such as a receptor activator of nuclear factor kappa-Β ligand inhibitor (denosumab) and antiangiogenic agents, have had the same issue. The purpose of this research is to determine if the application of human amniotic membrane (hAM) may be used as a therapy for MRONJ. Material and Methods: A multi-source database (MEDLINE, EMBASE, AMED, and CENTRAL) systematic search was performed. The major objective of this study is to obtain an understanding of the efficacy of hAM when it is employed as a treatment modality for MRONJ. The protocol of this review was registered in the INPLASY register under the number NPLASY202330010. Results: The authors were able to include a total of five studies for the quality analysis, whereas for the quantity evaluation, only four studies were eligible. A total of 91 patients were considered for the investigation. After treatment with human amniotic membrane (hAM), a recurrence of osteonecrosis was observed in n = 6 cases (8.8%). The combined efficacy of surgical therapy and the use of hAM resulted in an overall success rate of 91.2%. Intraoperative complications were only documented in one article, and they were mostly caused by the positioning of the hAM, which led to wound breakdown at the surgical site. Conclusions: Based on the small amount of data and low-quality research included in this study, using human amniotic membranes to treat MRONJ might represent a feasible option. Nevertheless, further studies with a wider patient population are required to understand the long-term impacts.

Effects of Ginsenoside Rg1 on the Biological Behavior of Human Amnion-Derived Mesenchymal Stem/Stromal Cells (hAD-MSCs)

Ginsenoside Rg1 (Rg1) is purified from ginseng with various pharmacological effects, which might facilitate the biological behavior of human amnion-derived mesenchymal stem/stromal cells (hAD-MSCs). This study is aimed at investigating the effects of Rg1 on the biological behavior, such as viability, proliferation, apoptosis, senescence, migration, and paracrine, of hAD-MSCs. hAD-MSCs were isolated from human amnions. The effects of Rg1 on the viability, proliferation, apoptosis, senescence, migration, and paracrine of hAD-MSCs were detected by CCK-8, EdU, flow cytometry, SA-β-Gal staining, wound healing, and ELISA assays, respectively. The protein expression levels were detected by western blot. Cell cycle distribution was evaluated using flow cytometry. We found that Rg1 promoted hAD-MSC cycle progression from G0/G1 to S and G2/M phases and significantly increased hAD-MSC proliferation rate. Rg1 activated PI3K/AKT signaling pathway and significantly upregulated the expressions of cyclin D, cyclin E, CDK4, and CDK2 in hAD-MSCs. Inhibition of PI3K/AKT signaling significantly downregulated the expressions of cyclin D, cyclin E, CDK4, and CDK2, prevented cell cycle progression, and reduced hAD-MSC proliferation induced by Rg1. hAD-MSC senescence rate was significantly increased by D-galactose, while the elevated hAD-MSC senescence rate induced by D-galactose was significantly decreased by Rg1 treatment. D-galactose significantly induced the expressions of senescence markers, p16^INK4a, p14^ARF, p21^CIP1, and p53 in hAD-MSCs, while Rg1 significantly reduced the expressions of those markers induced by D-galactose in hAD-MSCs. Rg1 significantly promoted the secretion of IGF-I in hAD-MSCs. Rg1 reduced the hAD-MSC apoptosis rate. However, the difference was not significant. Rg1 had no influence on hAD-MSC migration. Altogether, our results demonstrate that Rg1 can promote the viability, proliferation, and paracrine and relieve the senescence of hAD-MSCs. PI3K/AKT signaling pathway is involved in the promotive effect of Rg1 on hAD-MSC proliferation. The protective effect of Rg1 on hAD-MSC senescence may be achieved via the downregulation of p16^INK4A and p53/p21^CIP1 pathway.

Comparative Analysis of Co-Cultured Amniotic Cell-Conditioned Media with Cell-Free Amniotic Fluid Reveals Differential Effects on Epithelial–Mesenchymal Transition and Myofibroblast Activation

Myofibroblast activation is a cellular response elicited by a variety of physiological or pathological insults whereby cells initiate a coordinated response intended to eradicate the insult and then revert back to a basal state. However, an underlying theme in various disease states is persistent myofibroblast activation that fails to resolve. Based on multiple observations, we hypothesized that the secreted factors harvested from co-culturing amniotic stem cells might mimic the anti-inflammatory state that cell-free amniotic fluid (AF) elicits. We optimized an amnion epithelial and amniotic fluid cell co-culture system, and tested this hypothesis in the context of myofibroblast activation. However, we discovered that co-cultured amniotic cell conditioned media (coACCM) and AF have opposing effects on myofibroblast activation: coACCM activates the epithelial–mesenchymal transition (EMT) and stimulates gene expression patterns associated with myofibroblast activation, while AF does the opposite. Intriguingly, extracellular vesicles (EVs) purified from AF are necessary and sufficient to activate EMT and inflammatory gene expression patterns, while the EV-depleted AF potently represses these responses. In summary, these data indicate that coACCM stimulates myofibroblast activation, while AF represses it. We interpret these findings to suggest that coACCM, AF, and fractionated AF represent unique biologics that elicit different cellular responses that are correlated with a wide variety of pathological states, and therefore could have broad utility in the clinic and the lab.

Hepatic and Adrenocortical Choristomas in the Placenta

Background Hepatic and adrenocortical choristomas are unusual findings in the placenta. This meta-analysis includes our own case report and 23 previously reported cases. We searched for patterns of associated placental, fetal and maternal aberrations in order to determine whether these choristomas are clinically relevant. Case report: In our case, abortion was induced due to fetal central nervous system and renal malformations. In the placenta a hepatic choristoma (<0.1 cm), thrombangiitis obliterans and a single umbilical artery were found. Results: In the literature, the majority of lesions were ≤1.0 cm (n = 21/24, 87.5%) and two hepatic choristomas manifested within chorangiomas. In a subfraction of cases, we found an association with twin/triple pregnancies (n = 6/24, 25%) and heterogeneous non-hepatic/non-adrenal malformations in fetuses (n = 4/24, 17%). Conclusion: Hepatic and adrenocortical choristomas are benign, could be based on focal epigenetic changes and might be related to chorangiomas but are not associated with a particular disease pattern or risk profile.

Long-term culture of rat hepatocytes using human amniotic membrane as a culture substrate

Amniotic membrane is attracting attention as a new material for regenerative medicine. We herein report that the culture of primary rat hepatocytes on human amniotic membrane maintained their morphology and their production of albumin for at least two months. Human amniotic membrane was collected during planned cesarean section and kept frozen until usage. Primary rat hepatocytes were plated on human amniotic membrane. Hepatocytes accumulated as colonies on amniotic membrane, and their rat albumin level was maintained for two months. Their three-dimensional structure on extracellular matrix, which is abundant in amniotic membranes might influence the maintenance of the hepatocyte-specific function.

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Long-term primary culture of rat hepatocyte on the human amniotic membrane was successful.

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Albumin production from primary isolated hepatocytes was maintained for the long term.

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Amniotic membrane provided the situation of 3D structure for isolated rat hepatocyte.

Chorionic villus-derived mesenchymal stem cell-mediated autophagy promotes the proliferation and invasiveness of trophoblasts under hypoxia by activating the JAK2/STAT3 signalling pathway

BACKGROUND

Trophoblast dysfunction during pregnancy is fundamentally involved in preeclampsia. Several studies have revealed that human chorionic villous mesenchymal stem cells (CV-MSCs) could regulate trophoblasts function.

RESULTS

To understand how human chorionic villous mesenchymal stem cells (CV-MSCs) regulate trophoblast function, we treated trophoblasts with CV-MSC supernatant under hypoxic conditions. Treatment markedly enhanced proliferation and invasion and augmented autophagy. Transcriptome and pathway analyses of trophoblasts before and after treatment revealed JAK2/STAT3 signalling as an upstream regulator. In addition, STAT3 mRNA and protein levels increased during CV-MSC treatment. Consistent with these findings, JAK2/STAT3 signalling inhibition reduced the autophagy, survival and invasion of trophoblasts, even in the presence of CV-MSCs, and blocking autophagy did not affect STAT3 activation in trophoblasts treated with CV-MSCs. Importantly, STAT3 overexpression increased autophagy levels in trophoblasts; thus, it positively regulated autophagy in hypoxic trophoblasts. Human placental explants also proved our findings by showing that STAT3 was activated and that LC3B-II levels were increased by CV-MSC treatment.

CONCLUSION

In summary, our data suggest that CV-MSC-dependent JAK2/STAT3 signalling activation is a prerequisite for autophagy upregulation in trophoblasts.

Human Amniotic Mesenchymal Stem Cells Inhibit aGVHD by Regulating Balance of Treg and T Effector Cells

Background

Acute graft versus host disease (aGVHD) remains a leading cause of transplant-related mortality following allogeneic haematopoietic cell transplantation (allo-HCT). Human amniotic mesenchymal stem cells (hAMSCs) are a novel mesenchymal stem cells (MSCs), which have stronger proliferation and immunomodulatory ability compared with bone marrow mesenchymal stem cells (BM-MSCs). Besides, as the amniotic membrane is often treated as medical waste after delivery, hAMSCs can be obtained conveniently and noninvasively. The aim of this study was to explore the therapeutic efficacy and underlying mechanisms of hAMSCs transplantation for the humanized aGVHD mouse model.

Methods

We established a humanized aGVHD mouse model by transplanting human peripheral blood mononuclear cells (PBMCs) into NOD-Prkdc^scidIL2rγ^null (NPG) mice, human amniotic membrane collected from discarded placenta of healthy pregnant women after delivery and hAMSCs were extracted from amniotic membrane and expanded in vitro. Mice were divided into untreated group (Control), aGVHD group (aGVHD), and hAMSCs treatment group (aGVHD+hAMSCs), the hAMSCs labeled with GFP were administered to aGVHD mice to explore the homing ability of hAMSCs. T effector and regulatory T cells (Tregs) levels and cytokines of each group in target organs were detected by flow cytometry and cytometric bead array (CBA), respectively.

Results

We successfully established a humanized aGVHD mouse model using NPG mice. The hAMSCs have the ability to inhibit aGVHD in this mouse model through reduced villous blunting and lymphocyte infiltration of the gut while reducing inflammatory edema, tissue destruction and lymphocyte infiltration into the parenchyma of the liver and lung. hAMSCs suppressed CD3+CD4+ T and CD3+CD8+ T cell expression and increased the proportion of Tregs, and besides, hAMSCs can reduce the levels of IL-17A, INF-γ, and TNF in aGVHD target organs.

Conclusion

The NPG murine environment was capable of activating human T cells to produce aGVHD pathology to mimic aGVHD as in humans. The hAMSCs controlled aGVHD by decreasing inflammatory cytokine secretion within target organs by modulating the balance of Tregs and T effector cells in humanized mice.

Computer-assisted surgery with custom prostheses and human amniotic membrane in a patient with bilateral class IV TMJ reankylosis: a case report

A gold-standard technique has yet to be found for the treatment of temporomandibular joint ankylosis (TMJa), particularly in patients with recurring ankylosis. A 58-year-old male patient, with a history of multiple TMJ surgeries and severe limitation of mouth opening (maximum interincisal distance [MID] was 10 mm). Computerised tomography (CT) imaging highlighted a bilateral type IV ankylosis. The surgical guides were manufactured using a 3D printing method after obtaining a proper design of the osteotomy lines. The positioning of the fossa and condyle components of the custom TMJ prosthesis was digitally performed. Osteotomies were carried out using surgical guides and TMJ prostheses were placed as per the virtual planning. A human amniotic mambrana is inserted between the two prosthetic components to avoid ranchylosis. The post-operative CT showed the correct positioning of the condylar prosthesis. MID after 10 days was 37 mm. Total joint reconstruction surgery using 3D virtual surgical planning may be an effective surgical option for achieving a precise surgical outcome and making use of a single-stage approach in cases of TMJa and the use of the amniotic membrane, thanks to its healing properties and reduction of pain perception, seems to improve the quality of the immediate post-operative period.

11-Ketotestosterone is a major androgen produced in porcine adrenal glands and testes

Porcine steroid hormone profiles have some unique characteristics. We previously studied human and murine steroidogenesis using steroidogenic cells-derived from mesenchymal stem cells (MSCs). To investigate porcine steroidogenesis, we induced steroidogenic cells from porcine subcutaneous preadipocytes (PSPA cells), which originate from MSCs. Using cAMP, adenovirus-mediated introduction of steroidogenic factor-1 (SF-1)/adrenal 4-binding protein (Ad4BP) induced the differentiation of PSPA cells into sex steroid-producing cells. Introducing SF-1/Ad4BP also induced the aldo-keto reductase 1C1 (AKR1C1) gene. Porcine AKR1C1 had 17β-hydroxysteroid dehydrogenase activity, which converts androstenedione and 11-ketoandrostenedione into testosterone (T) and 11-ketotestosteorne (11KT). Furthermore, differentiated cells expressed hydroxysteroid 11β-dehydrogenase 2 (HSD11B2) and produced 11KT. HSD11B2 was expressed in testicular Leydig cells and the adrenal cortex. 11KT was present in the plasma of both immature male and female pigs, with slightly higher levels in the male pigs. T levels were much higher in the male pigs. It is noteworthy that in the female pigs, the 11KT levels were >10-fold higher than the T levels. However, castration altered the 11KT and T plasma profiles in the male pigs to near those of the females. 11KT induced endothelial nitric oxide synthase (eNOS) in porcine vascular endothelial cells. These results indicate that 11KT is produced in porcine adrenal glands and testes, and may regulate cardiovascular functions through eNOS expression.

Human amniotic membrane: an improvement in the treatment of Medication-related osteonecrosis of the jaw (MRONJ)? A case-control study

The aim of this article is to report the results obtained by the use of HAM in surgical wound healing and the reduction of relapse in patients affected by Medication-related osteonecrosis of the jaw (MRONJ).The study involved patients with the diagnosis of MRONJ, surgically treated between October 2016 and April 2019, in a case-control setting. Enrolled patients were randomly divided into 2 groups. One group will be treated with resective surgery and with the insertion of HAM patch (Group A), while the second group had been treated exclusively with resective surgery (Group B).The patients underwent MRONJ surgical treatment with the placement of amniotic membrane patches at the wound site. Data regarding the long-term complications/functions were evaluated at 3, 6, 12, and 24 months after surgery. Pain measurements were performed before the intervention (T0), 7(T1) and 30(T2) days after surgery. 49 patients were included in the study. 2 patients of GROUP A after 30 days since they were surgically treated showed persistent bone exposure. 5 patients of group B demonstrated a lack of healing of the surgical wound with the persistence of bone exposed to 30 days after surgery. Statistical analysis ruled out any difference in OUTCOME (relapse) between GROUP A and B (p = 0.23). However, the Fisher test highlighted a significant difference between the use of HAM and only surgical treatment in pain at rest (p = 0.032). The use of amniotic membrane implement the patient's quality of life and reduce pain perception. has a learning curve that is fast enough to justify its routine use.

A Review of Placenta and Umbilical Cord-Derived Stem Cells and the Immunomodulatory Basis of Their Therapeutic Potential in Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD) is a devastating lung disorder of preterm infants as a result of an aberrant reparative response following exposures to various antenatal and postnatal insults. Despite sophisticated medical treatment in this modern era, the incidence of BPD remains unabated. The current strategies to prevent and treat BPD have met with limited success. The emergence of stem cell therapy may be a potential breakthrough in mitigating this complex chronic lung disorder. Over the last two decades, the human placenta and umbilical cord have gained increasing attention as a highly potential source of stem cells. Placenta-derived stem cells (PDSCs) and umbilical cord-derived stem cells (UCDSCs) display several advantages such as immune tolerance and are generally devoid of ethical constraints, in addition to their stemness qualities. They possess the characteristics of both embryonic and mesenchymal stromal/stem cells. Recently, there are many preclinical studies investigating the use of these cells as therapeutic agents in neonatal disease models for clinical applications. In this review, we describe the preclinical and clinical studies using PDSCs and UCDSCs as treatment in animal models of BPD. The source of these stem cells, routes of administration, and effects on immunomodulation, inflammation and regeneration in the injured lung are also discussed. Lastly, a brief description summarized the completed and ongoing clinical trials using PDSCs and UCDSCs as therapeutic agents in preventing or treating BPD. Due to the complexity of BPD, the development of a safe and efficient therapeutic agent remains a major challenge to both clinicians and researchers.

Treatment of COVID-19 Pneumonia: the Case for Placenta-derived Cell Therapy

Nearly 500'000 fatalities due to COVID-19 have been reported globally and the death toll is still rising. Most deaths are due to acute respiratory distress syndrome (ARDS), as a result of an excessive immune response and a cytokine storm elicited by severe SARS-CoV-2 lung infection, rather than by a direct cytopathic effect of the virus. In the most severe forms of the disease therapies should aim primarily at dampening the uncontrolled inflammatory/immune response responsible for most fatalities. Pharmacological agents - antiviral and anti-inflammatory molecules - have not been able so far to achieve compelling results for the control of severe COVID-19 pneumonia. Cells derived from the placenta and/or fetal membranes, in particular amniotic epithelial cells (AEC) and decidual stromal cells (DSC), have established, well-characterized, potent anti-inflammatory and immune-modulatory properties that make them attractive candidates for a cell-based therapy of COVID19 pneumonia. Placenta-derived cells are easy to procure from a perennial source and pose minimal ethical issues for their utilization. In view of the existing clinical evidence for the innocuousness and efficiency of systemic administration of DSCs or AECs in similar conditions, we advocate for the initiation of clinical trials using this strategy in the treatment of severe COVID-19 disease.

Characteristics and Therapeutic Potential of Human Amnion-Derived Stem Cells

Stem cells including embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs) and adult stem cells (ASCs) are able to repair/replace damaged or degenerative tissues and improve functional recovery in experimental model and clinical trials. However, there are still many limitations and unresolved problems regarding stem cell therapy in terms of ethical barriers, immune rejection, tumorigenicity, and cell sources. By reviewing recent literatures and our related works, human amnion-derived stem cells (hADSCs) including human amniotic mesenchymal stem cells (hAMSCs) and human amniotic epithelial stem cells (hAESCs) have shown considerable advantages over other stem cells. In this review, we first described the biological characteristics and advantages of hADSCs, especially for their high pluripotency and immunomodulatory effects. Then, we summarized the therapeutic applications and recent progresses of hADSCs in treating various diseases for preclinical research and clinical trials. In addition, the possible mechanisms and the challenges of hADSCs applications have been also discussed. Finally, we highlighted the properties of hADSCs as a promising source of stem cells for cell therapy and regenerative medicine and pointed out the perspectives for the directions of hADSCs applications clinically.

Amnion-Derived Mesenchymal Stem Cell Exosomes-Mediated Autophagy Promotes the Survival of Trophoblasts Under Hypoxia Through mTOR Pathway by the Downregulation of EZH2

Human amnion-derived mesenchymal stem cells (AD-MSCs) have been reported as a promising effective treatment to repair tissue. Trophoblast dysfunction during pregnancy is significantly involved in the pathogenesis of preeclampsia (PE). To understand how AD-MSCs regulated trophoblast function, we treated trophoblasts with AD-MSC-derived exosomes under hypoxic conditions. The treatment markedly enhanced the trophoblast proliferation and autophagy. Furthermore, significant decrease of EZH2 levels and inactivation of mTOR signaling were observed in AD-MSC exosomes-treated trophoblasts. Consistent with these findings, overexpression of EZH2 activated the mTOR signaling in trophoblasts, and reduced the autophagy and survival of trophoblasts, even in the presence of AD-MSC-derived exosomes. In addition, EZH2 inhibition exhibited the same trophoblast autophagy-promoting effect as induced by AD-MSC-derived exosomes, also accompanied by the inactivation of mTOR signaling. Importantly, when EZH2 was overexpressed in trophoblasts treated with PQR620, a specific mTOR signaling inhibitor, the autophagy and proliferation in trophoblasts were decreased. Studies on human placental explants also confirmed our findings by showing that the expression levels of EZH2 and mTOR were decreased while the autophagy-associated protein level was increased by AD-MSC-derived exosome treatment. In summary, our results suggest that EZH2-dependent mTOR signaling inactivation mediated by AD-MSC-derived exosomes is a prerequisite for autophagy augmentation in hypoxic trophoblasts.