Endometrial stem cells in regenerative medicine

Nerve Regeneration Through Differentiation of Endometrial-Derived Mesenchymal Stem Cells into Nerve-Like Cells Using Polyacrylonitrile/Chitosan Conduit and Berberine in a Rat Sciatic Nerve Injury Model

Nervous injuries are common in humans. One of the most advanced treatment methods is neural tissue engineering. This research aims to utilize nerve-like cells (NLCs) derived from endometrial mesenchymal stem cells (EnMSCs) on a polyacrylonitrile/chitosan (PAN/CS) scaffold, along with berberine, for the reconstruction of a rat sciatic nerve injury model. In this experimental study, EnMSCs were obtained through enzymatic digestion and identified using flow cytometry and their differentiation into adipocyte and osteoblast. PAN nanofiber scaffolds were produced through electrospinning, and EnMSCs were neurally differentiated on these scaffolds for grafting into an animal model. The expression of Nestin, Map-2, Tuj-1, and NF genes in NLCs was confirmed through RT-PCR and immunocytochemistry. Twenty-five adult male rats were used in this study, divided into 5 groups: (1) Scaffold/Cells/Berberine, (2) Scaffold/Cells, (3) Scaffold, (4) Berberine, and (5) Control. The animals were maintained for 8 weeks, and their sciatic nerve function (SFI) was assessed. Additionally, histological examinations were performed using hematoxylin/eosin, luxol fast blue staining, and immunohistochemistry. According to the results, extraction, identification, and differentiation of EnMSCs and fabrication of PAN conduit and its transplantation were successfully performed. The best behavioral performance and histology were observed in the Scaffold/Cells/Berberine group. The SFI test results were -24.08 for the Scaffold/Cells/Berberine group and -39.27 for the control group. The nerve diameter in these two groups was 591 µm and 80 µm, respectively, and the percentage of new nerve formation was 18.5% in the Scaffold/Cells/Berberine group and 0.2% in the control group. The immunohistochemistry results demonstrated that the intensity of the green color was higher in the groups with cells compared to the groups without cells. Furthermore, in the luxol staining results, all groups showed a significant improvement compared to the control group. In the Scaffold/Cells/Berberine group, fibers, and axons appeared denser, more organized, and displayed a higher intensity of blue staining. According to the results of this study, EnMSCs demonstrated efficient differentiation into NLCs. With the assistance of PAN/CS scaffolds and simultaneous administration of berberine, EnMSCs have the potential for nerve regeneration and recovery from sciatic nerve injury in the rat animal model.

Artemisin and human endometrial-derived stem cells improve cognitive function and synaptic plasticity in a rat model of Alzheimer disease and diabetes

Alzheimer disease (AD) is a common form of dementia associated with loss of memory and disruption of synaptic plasticity. There is a strong correlation between the pathophysiological features of AD and diabetes, including induction of oxidative stress, inflammation, and abnormality in blood vessels. Considering the brain's limited capacity to repair damage and the potential of stem cell-derived neural cells in the repair of neurodegenerative disease, we investigated the effects of artemisinin and TSP‑1‑human endometrial-derived-derived stem cells (TSP‑1‑hEDSCs) on the cognitive function and synaptic plasticity in AD-diabetes rats. The authors previously showed that artemisinin and TSP‑1‑hEDSCs suppressed oxidative stress and inflammation in AD-diabetes rats. Thrombospondins-1 (TSPs-1) is a glycoprotein that inhibits angiogenesis. AD and diabetes were induced using streptozotocin. Synaptic plasticity and learning and memory function were studied using the Morris water maze and electrophysiological test, respectively. Streptozotocin increased traveled swimming distance and escape latency in the morris water maze test, decreased the percent time spent in the target quadrant, inhibited the long-term potentiation (LTP), and increased the blood glucose levels. Simultaneous or separate administration of artemisinin and TSP‑1‑hEDSCs decreased the blood levels of glucose and improved cognitive tasks and synaptic plasticity by considerably reducing traveled swimming distance and escape latency, increasing the percent time spent in the target quadrant, and retrieval of the LTP; therefore, they could be utilized as an adjunct treatment for AD treatment. These results may be due to a decrease in oxidative stress and inflammation.

Extracellular Matrix-Based and Electrospun Scaffolding Systems for Vaginal Reconstruction

Congenital vaginal anomalies and pelvic organ prolapse affect different age groups of women and both have significant negative impacts on patients' psychological well-being and quality of life. While surgical and non-surgical treatments are available for vaginal defects, their efficacy is limited, and they often result in long-term complications. Therefore, alternative treatment options are urgently needed. Fortunately, tissue-engineered scaffolds are promising new treatment modalities that provide an extracellular matrix (ECM)-like environment for vaginal cells to adhere, secrete ECM, and be remodeled by host cells. To this end, ECM-based scaffolds or the constructs that resemble ECM, generated by self-assembly, decellularization, or electrospinning techniques, have gained attention from both clinicians and researchers. These biomimetic scaffolds are highly similar to the native vaginal ECM and have great potential for clinical translation. This review article aims to discuss recent applications, challenges, and future perspectives of these scaffolds in vaginal reconstruction or repair strategies.

Therapeutic restoration of female reproductive and endocrine dysfunction using stem cells

Millions of women worldwide suffer from infertility associated with gynecologic disorders such as premature ovarian insufficiency, polycystic ovary syndrome, Asherman syndrome, endometriosis, preeclampsia, and fallopian tube obstruction. These disorders can lead to infertility and thereby affect the quality of life of the infertile couple because of their psychological impact and significant costs. In recent years, stem cell therapy has emerged as a therapeutic approach to repair or replace damaged tissues or organs. This review describes the recent development as well as the underlying mechanisms of stem cell therapy for a variety of female reproductive diseases, offering us new therapeutic options for the treatment of female reproductive and endocrine dysfunction.

Using Odontoblasts Derived from Dog Endometrial Stem Cells Encapsulated in Fibrin Gel Associated with BMP-2 in a Rat Pulp-Capping Model

This study aimed to treat dental injuries by utilizing one of the most advanced tissue engineering techniques. In this study, an in vitro model was employed to investigate the proliferation and odontogenic differentiation of canine endometrial stem cells (C-EnSCs). Furthermore, the dentin regeneration potential of odontoblast like-cells (OD) derived from C-EnSCs was assessed in rats. The C-EnSCs were isolated by the enzymatic method and identified by flow cytometry. The C-EnSCs were encapsulated in fibrin gel associated with signaling factors to create the proper conditions for cell growth and differentiation. Then, the OD cells were associated with bone morphologic protein-2 (BMP-2) to promote dentin formation in vivo. The animal model used to evaluate the regenerative effect of cells and biomaterials included the preparation of the left maxillary first molar of rats for direct pulp capping operation. Animals were divided into four groups: group 1, a control group without any treatment, group 2, which received fibrin, group 3, which received fibrin with ODs (fibrin/ODs), and group 4, which received fibrin with ODs and BMP-2 (fibrin/ODs/BMP-2). The morphological observations showed the differentiation of C-EnSCs into adipose, bone, neural cells, and ODs. Furthermore, the histomorphometric data of the treated teeth showed how fibrin gel and BMP2 at a concentration of 100 ng/mL provided an optimal microenvironment for regenerating dentin tissue in rats, which was increased significantly with the presence of OD cells within eight weeks. Our study showed that using OD cells derived from C-EnSCs encapsulated in fibrin gel associated with BMP2 can potentially be an appropriate candidate for direct pulp-capping and dentin regeneration.

Endometrial Stem Cells and Their Applications in Intrauterine Adhesion

Intrauterine adhesion (IUA), resulting from pregnancy or nonpregnant uterine trauma, is one of the major causes of abnormal menstruation, infertility, or repeated pregnancy loss. Although a few methods, including hysteroscopy and hormone therapy, are routinely used for its diagnosis and treatment, they cannot restore tissue regeneration. Stem cells, which have self-renewal and tissue regeneration abilities, have been proposed as a promising therapy for patients with severe IUAs. In this review, we summarize the origin and features of endometrium-associated stem cells and their applications in the treatment of IUAs based on animal models and human clinical trials. We expect that this information will help to elucidate the underlying mechanism for tissue regeneration and to improve the design of stem cell-based therapies for IUAs.

Stem Cells and Organs-on-chips: New Promising Technologies for Human Infertility Treatment

Having biological children remains an unattainable dream for most couples with reproductive failure or gonadal dysgenesis. The combination of stem cells with gene editing technology and organ-on-a-chip models provides a unique opportunity for infertile patients with impaired gametogenesis caused by congenital disorders in sex development or cancer survivors. But how will these technologies overcome human infertility? This review discusses the regenerative mechanisms, applications, and advantages of different types of stem cells for restoring gametogenesis in infertile patients, as well as major challenges that must be overcome before clinical application. The importance and limitations of in vitro generation of gametes from patient-specific human-induced pluripotent stem cells (hiPSCs) will be discussed in the context of human reproduction. The potential role of organ-on-a-chip models that can direct differentiation of hiPSC-derived primordial germ cell-like cells to gametes and other reproductive organoids is also explored. These rapidly evolving technologies provide prospects for improving fertility to individuals and couples who experience reproductive failure.

Stem Cell Therapy in Limb Ischemia: State-of-Art, Perspective, and Possible Impacts of Endometrial-Derived Stem Cells

As an evidence-based performance, the rising incidence of various ischemic disorders has been observed across many nations. As a result, there is a growing need for the development of more effective regenerative approaches that could serve as main therapeutic strategies for the treatment of these diseases. From a cellular perspective, promoted complex inflammatory mechanisms, after inhibition of organ blood flow, can lead to cell death in all tissue types. In this case, using the stem cell technology provides a safe and regenerative approach for ischemic tissue revascularization and functional cell formation. Limb ischemia (LI) is one of the most frequent ischemic disease types and has been shown to have a promising regenerative response through stem cell therapy based on several clinical trials. Bone marrow-derived mononuclear cells (BM-MNCs), peripheral blood CD34-positive mononuclear cells (CD34+ PB-MNCs), mesenchymal stem cells (MSCs), and endothelial stem/progenitor cells (ESPCs) are the main, well-examined stem cell types in these studies. Additionally, our investigations reveal that endometrial tissue can be considered a suitable candidate for isolating new safe, effective, and feasible multipotent stem cells for limb regeneration. In addition to other teams’ results, our in-depth studies on endometrial-derived stem cells (EnSCs) have shown that these cells have translational potential for limb ischemia treatment. The EnSCs are able to generate diverse types of cells which are essential for limb reconstruction, including endothelial cells, smooth muscle cells, muscle cells, and even peripheral nervous system populations. Hence, the main object of this review is to present stem cell technology and evaluate its method of regeneration in ischemic limb tissue.

Di-(2-ethylhexyl) Phthalate Triggers Proliferation, Migration, Stemness, and Epithelial-Mesenchymal Transition in Human Endometrial and Endometriotic Epithelial Cells via the Transforming Growth Factor-β/Smad Signaling Pathway

Di-(2-ethylhexyl) phthalate (DEHP) is a frequently used plasticizer that may be linked to the development of endometriosis, a common gynecological disorder with a profound impact on quality of life. Despite its prevalence, vital access to treatment has often been hampered by a lack of understanding of its pathogenesis as well as reliable disease models. Recently, epithelial–mesenchymal transition (EMT) has been suggested to have a significant role in endometriosis pathophysiology. In this study, we found that DEHP treatment enhanced proliferation, migration, and inflammatory responses, along with EMT and stemness induction in human endometrial and endometriotic cells. The selective transforming growth factor-β (TGF-β) receptor type 1/2 inhibitor LY2109761 reversed the DEHP-induced cell proliferation and migration enhancement as well as the increased expression of crucial molecules involved in inflammation, EMT, and stemness, indicating that DEHP-triggered phenomena occur via the TGF-β/Smad signaling pathway. Our study clearly defines the role of DEHP in the etiology and pathophysiological mechanisms of endometriosis and establishes an efficient disease model for endometriosis using a biomimetic 3D cell culture technique. Altogether, our data provide novel etiological and mechanistic insights into the role of DEHP in endometriosis pathogenesis, opening avenues for developing novel preventive and therapeutic strategies for endometriosis.

Endometrium Derived Stem Cells as Potential Candidates in Nervous System Repair

Limited cell division and lack of endogenous repair mechanisms in the central nervous system, hampers tissue repair following neurodegenerative diseases or tissue injuries. Unlike central nervous system; peripheral nervous system has some capacity to repair after injury, but in case of critical sized defects the use of supporting cells in the neural guidance channels seems inevitable to obtain a satisfactory functional recovery. Stem cell therapies have provided new frontiers in the repair of nervous system largely through paracrine secretion mechanisms. The therapeutic potential of stem cells differs according to their tissue of origin, mode of isolation, administration route, and passage number. During the past decades, studies have been focused on stem cells harvested from disposable tissues such as menstrual blood or biopsies from endometrium. These cells are characterized by their high differentiation and proliferation potential, ease of harvest, and lack of ethical concerns. In the current review, we will discuss the prospects and challenges of endometrial stem cells' application in nervous system repair.

Endometrial Regenerative Cell-Derived Conditioned Medium Alleviates Experimental Colitis

Background

Traditional interventions can play a certain role in attenuating ulcerative colitis (UC), known as one type of inflammatory bowel diseases, but sometimes are not effective. Endometrial regenerative cells (ERCs) have been shown to exert immunosuppressive effects in different models of inflammation, and stem cell-derived conditioned media (CM) have advantages over cell therapy in terms of easy access and direct action. However, whether ERC-CM could alleviate colitis remains unclear and will be explored in this study.

Methods

Menstrual blood was collected from healthy female volunteers to obtain ERCs and ERC-CM. Acute colitis was induced by 3% dextran sodium sulfate (DSS), and ERC-CM was injected on days 4, 6, and 8, respectively, after induction. The disease activity index was calculated through the record of weight change, bleeding, and fecal viscosity during the treatment process. Histological features, macrophage and CD4⁺ T cell in the spleen and colon, and cytokine profiles in the sera and colon were measured. In addition, an in vitro lymphocyte proliferation assay was measured by using a CCK-8 kit in this study.

Results

ERC-CM treatment significantly improved the symptoms and histological changes in colitis mice. ERC-CM increased the percentage of Tregs in the spleen and colon but decreased the percentages of M1 macrophages and Th1 and Th17 cells in the spleen and decreased the population of Th17 cells in the colon. In addition, ERC-CM treatment decreased the local expression of TNF-α, IL-6, and iNOS in the colon. Furthermore, ERC-CM increased the levels of anti-inflammatory cytokines IL-10 and IL-27 but decreased proinflammatory cytokines IL-6 and IL-17 in the sera. In addition, ERC-CM significantly inhibited ConA-induced mouse lymphocyte proliferation in vitro.

Conclusion

The results suggest that ERC-CM can exert similar therapeutic effects as ERCs and could be explored for future application of cell-free therapy in the treatment of colitis.

Decidualization Potency and Epigenetic Changes in Human Endometrial Origin Stem Cells During Propagation

Human endometrium derived mesenchymal stem cells (hEndSCs) offer a great promise for regenerative medicine and reproductive system disorders treatment methods based on cell therapy due to their broad differentiation potential and highly efficient proliferation. In our study, we investigated the characteristics of hEndSCs that were isolated from two sources: endometrium and menstrual blood, which both contain endometrial origin stem cells. Changes in gene and protein expression levels during long-term cultivation and decidualization potential were examined in endometrial stem cells (EndSCs) and menstrual blood stem cells (MenSCs). The decidualization process was induced on early and late passages of hEndSCs using dibutyryl cyclic-AMP (db-cAMP) and medroxyprogesterone acetate (MPA) agents. We demonstrated that after long-term cultivation of hEndSCs the expression of typical mesenchymal stromal cell surface markers such as CD44, CD73, CD90, CD105 and perivascular marker CD146 remains at a similar level throughout long-term cultivation. Additionally, hematopoietic and endothelial markers CD34, CD45 were also tested, they were negative in all cases. Analyzed stem cells gene markers, such as OCT4, SOX2, NANOG, KLF4, showed similar expression in all passages of hEndSCs. RT-qPCR results demonstrated that the expression of cell cycle control associated genes - CDK2, CCNA2, CCNE2, p21, p53 and Rb, among all groups was very similar. Expression of genes associated with senescence (ATM, JUND, TOP2A, MYC) was maintained at a similar level throughout passaging. In addition, Western blot analysis was used to assess changes in proteins’ levels associated to epigenetics (EZH2, SUZ12, H3K27me3) and cell cycle control (cyclinE1, p53) during long-term cultivation. The levels of proteins associated with epigenetic changes were fluctuated slightly depending on the patient. Also, we demonstrated that in all induced hEndSCs the expression of decidualization markers Prolactin (PRL), IGFBP1 and WNT4 was upregulated. In conclusion, we demonstrated successful decidualization of stem cells derived from two reproductive system resources: endometrium and menstrual blood by using db-cAMP and MPA regardless of the length of the stem cell passaging. According these findings, we suppose that endometrium derived stem cells and menstrual blood derived stem cells could have a potency not only for endometrium tissue regeneration, but could also become a successful therapy for reproductive system disorders, including infertility or recurrent pregnancy loss.

Human Endometrial Stromal/Stem Cells Inhibit Apoptosis in Cisplatin-Induced Acute Kidney Injury in Male Wistar Rats

OBJECTIVE

Acute kidney injury (AKI) is referred to as sudden decline in the function of kidney. Human endometrial stromal/stem cells (hEnSCs) are mesenchymal stem cell (MSC)-like cells, which are suitable candidates for regenerative medicine purposes, yet the effect of hEnSCs on cisplatin-induced AKI has not been studied; therefore, the present study was conducted to investigate this gap in the literature.

MATERIALS AND METHODS

In this experimental study, hEnSCs were obtained from endometrial biopsy using collagenase I and were then cultured in DMEM/F12 medium. A total of 48 male Wistar rats (150-200 g) were classified into four groups: intact -receiving no treatment, model -receiving 5 mg/kg of body weight cisplatin, as well as phosphate-buffered saline (PBS) and cell -receiving either PBS or hEnSCs for three hours after cisplatin injection, respectively. Biochemical parameters, pathologic scores, apoptosis assay, Bcl-2 and Tnf-α expression were evaluated on day 5.

RESULTS

On day 5 post-transplantation we observed that HEnSCs injection has led to a decrease in both blood urea nitrogen (BUN) and serum creatinine (SCr), compared to the model and PBS groups (0.82 ± 0.03 vs. 1.42 ± 0.06, 1.09 ± 0.05 mg/dl and 61.53 ± 3.07 vs. 116.60 ± 2.12, 112.00 ± 1.35 mg/dl, respectively). The highest levels of pathologic scores were observed in model and PBS groups, while hEnSCs transplantation resulted in a decrease in pathologic scores (149.10 ± 7.03, 141.50 ± 4.68 vs. 118 ± 2.16). HEnSCs significantly decreased the percentage of TUNELpositive cells in the cell group compared with model and PBS groups (20.37 ±. 3.37 vs. 33.67 ± 1.79, 31.53 ± 1.05 in glomeruli and 15.10 ± 1.47 vs. 42.33 ± 1.72, 39.23 ± 1.61 in tubules). In addition, HEnSCs resulted in upregulation of Bcl-2 and downregulation of Tnf-α in the cisplatin-induced AKI.

CONCLUSION

Our results showed that injection of hEnSCs may improve AKI through lowering the amount of apoptosis in renal cells.

Hypothetical Role of Growth Factors to Reduce Intervertebral Disc Degeneration Significantly through Trained Biological Transformations

BACKGROUND

Given the evidence of little or no therapeutic benefit of injection-based growth factor therapies, it has been proposed that a naturally triggered uninterrupted blood circulation of the growth factors would be superior.

OBJECTIVE

We seek to stimulate discussions and more research about the possibility of using the already available growth factors found in the prostate gland and endometrium by starting novel educable physiology, known as biological transformations controlled by the mind.

METHODS

We summarized the stretch-gated ion channel mechanism of the cell membrane and offer several practical methods that can be applied by anyone, in order to stimulate and enhance the blood circulation of the growth factors from the seminal fluid to sites throughout the body. This study describes, in detail, the practical application of our earlier published studies about biological transformations.

RESULTS

A previously reported single-patient case study has been extended, adding more from his personal experiences to continually improve this novel physiological training and extending the ideas from our earlier findings in detail.

CONCLUSION

The biological transformation findings demonstrate the need for additional research to establish the benefits of these natural therapies to repair and rejuvenate tissues affected by various chronic diseases or aging processes.

Stem Cell-Based Therapy for Asherman Syndrome: Promises and Challenges

Asherman syndrome (AS) has an adverse effect on reproductive health and fertility by affecting endometrial regeneration. Stem cell-based therapies hold promise for future use in activating non-functional endometrium and reconstructing the endometrium in vivo. It has been postulated that various endometrial stem cells (EnSCs) are responsible for endometrial regeneration. Numerous studies have focused on bone marrow-derived stem cells (BMDSCs), which may provide new ideas for repairing endometrial lesions and reconstructing the endometrium. Other sources of stem cells, such as menstrual blood, umbilical cord, and amniotic membrane, have also attracted much attention as candidates for transplantation in AS. This review discusses the features and specific biomarkers among four types of resident endometrial stem cells, applications of four different sources of exogenous stem cells in AS, and development of stem cell therapy using biomaterials and exosomes.

Cell-based endometrial regeneration: current status and future perspectives

Endometrial-related disorders including Asherman's syndrome, thin endometrium, pelvic organ prolapse, and cesarean scar pregnancies can be accompanied by different symptoms such as amenorrhea, infertility, abnormal placental implantation and recurrent miscarriage. Different methods have been introduced to overcome these problems such as surgery and hormonal therapy but none of them has shown promising outcomes. On the other hand, the development of novel regenerative therapeutic strategies has opened new avenues for the treatment of endometrial-related deficiencies. In this regard, different types of scaffolds, acellular matrices and also cell therapy with adult or stem cells have been investigated for the treatment of endometrial-related deficiencies. In this paper, we review the current status of cell-based endometrium regeneration using scaffold dependent and scaffold-free methods and future perspectives in this field. Moreover, we discuss the endometrial diseases that can be candidates for cell-based treatments. Also, the cells with the potential for endometrial regeneration are explained.

Endometrial Stem/Progenitor cell (ES/PC) Marker Expression Profile in Adenosarcoma and Endometrial Stromal Sarcoma

BACKGROUND

The uterus is one of the most dynamic organs in the human body, and this dynamic homeostasis is supported by endometrial stem/progenitor cells (ES/PCs), which are heterogeneous in their phenotype and degree of differentiation. ES/PCs are generally localized in the endometrial stroma, the site of origin for adenosarcoma and endometrial stromal sarcoma (ESS). Subsets of ESSs and adenosarcomas harbor SUZ12 or DICER1 gene alterations, two genes with roles in embryonic stem cell biology. However, the possible contribution of ES/PCs to tumorigenesis is unexplored.

METHOD

We examined the expression of eleven ES/PC markers, along with three proteins expressed in the mature endometrial stroma (ER, PR and CD10) in 60 uterine tumors (24 low-, 11 high-grade ESS, 25 adenosarcomas). Protein expression profiles were assessed by unsupervised hierarchical clustering. miRNA expression profiles were examined in a subset of adenosarcoma with/without DICER1 mutations, using the NanoString platform.

RESULTS

ES/PC markers were variably expressed, and the tumors exhibited limited immunophenotypic resemblance to different ES/PCs. Within the ESSs, the ES/PC marker clustering pattern was prognostic for both overall and disease-free survival. Comparing adenosarcomas and ESSs, most high-grade ESSs clustered with one another, while low-grade ESSs and adenosarcomas tended to cluster with one another. Among the adenosarcomas, the miRNA expression profiles were varied with respect to the DICER1 mutation status, with pathway analysis pointing to dysregulated signal transduction and stem cell biology.

CONCLUSIONS

ESSs and adenosarcomas exhibit varying immunophenotypic resemblance to ES/PCs. These expression profiles have prognostic implications and may be genetically driven.

Intrauterine transplantation of autologous menstrual blood stem cells increases endometrial thickness and pregnancy potential in patients with refractory intrauterine adhesion

AIM

This study was designed to evaluate the effects of intrauterine transplantation of menstrual blood stem cells (MenSCs) on endometrial thickness and pregnancy outcomes in patients with refractory intrauterine adhesion (IUA).

METHODS

This study included a group of infertile women (n = 12, age 22-40 years), with refractory IUA. Autologous MenSCs isolated from the women's menstrual blood were expanded in vitro and transplanted into their uteruses, followed by hormone replacement therapy. Transvaginal ultrasound examination was performed to assess the endometrial thickness. Transabdominal ultrasound was conducted to detect pregnancy outcome.

RESULTS

Autologous MenSCs were successfully isolated and expanded from menstrual blood and transplanted into the uterus of each patient. A significant improvement of the endometrial thickness was observed from 3.9 ± 0.9 to 7.5 ± 0.6 mm (P < 0.001). No adverse reaction was observed. The duration of menstruation was increased from 2.4 ± 0.7 to 5.3 ± 0.6 days (P < 0.001). Five out of 12 patients achieved clinical pregnancy and the pregnancy rate was 41.7%.

CONCLUSIONS

Intrauterine transplantation of autologous MenSCs results in regeneration of endometrium, a prolongation of menstrual duration and an increase rate of pregnancy in patients with refractory IUA.

Histone acetylation and the role of histone deacetylases in normal cyclic endometrium

Histone acetylation is a critical epigenetic modification that changes chromatin architecture and regulates gene expression by opening or closing the chromatin structure. It plays an essential role in cell cycle progression and differentiation. The human endometrium goes through cycles of regeneration, proliferation, differentiation, and degradation each month; each phase requiring strict epigenetic regulation for the proper functioning of the endometrium. Aberrant histone acetylation and alterations in levels of two acetylation modulators - histone acetylases (HATs) and histone deacetylases (HDACs) - have been associated with endometrial pathologies such as endometrial cancer, implantation failures, and endometriosis. Thus, histone acetylation is likely to have an essential role in the regulation of endometrial remodelling throughout the menstrual cycle.

Therapeutic potential of menstrual blood stem cells in treating acute liver failure

BACKGROUND

Acute liver failure (ALF) is a significant and complex hepatic insult that may rapidly progress to life-threatening conditions. Recently, menstrual blood stem cells (MenSCs) have been identified as a group of easily accessible mesenchymal stem cells with the advantages of non-invasive acquisition, low immunogenicity, a greater capacity of self-renewal and multi-lineage differentiation, making them promising candidates for stem cell-based therapy to revolutionize the treatment strategies for liver failure.

AIM

To investigate the therapeutic potential of MenSCs for treating ALF in pigs and to dynamically trace the biodistribution of transplanted cells.

METHODS

MenSCs were labeled in vitro with PKH26, a lipophilic fluorescent dye. The treatment group received immediate transplantation of PKH26-labelled MenSCs (2.5 × 106/kg) via the portal vein after D-galactosamine injection, and the control group underwent sham operation. The survival time, liver function, and hepatic pathological changes were compared between the two groups. Three major organs (liver, lungs and spleen) were extracted from animals and imaged directly with the In vivo Imaging System (IVIS) at the predetermined time points. The regions of interest were drawn to quantify the cell uptake in different organs.

RESULTS

The labelling procedure did not affect the morphology, viability or multipotential differentiation of MenSCs. Biochemical analysis showed that the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL) and prothrombin time (PT) measured at selected time points 24 h after transplantation were significantly decreased in the treatment group (P < 0.05). The survival time of ALF animals was prolonged in the treatment group compared with the control group (75.75 ± 5.11 h vs 53.75 ± 2.37 h, log rank, P < 0.001). The liver pathological tissue in the MenSC treatment group showed obviously increased numbers of remaining hepatocytes and a comparatively slight necrotic degree and area. In addition, the IVIS imaging revealed that PKH26-positive MenSCs were clearly retained in the liver initially and then diffused through the systemic circulation. Interestingly, the signal intensity in the liver increased obviously at 36 h, which corresponded to the biochemical result that liver function deteriorated most rapidly at 24 - 36 h.

CONCLUSION

Our study demonstrates the therapeutic efficacy and homing ability of transplanted MenSCs in a large animal model of ALF and suggests that MenSC transplantation could be a promising strategy for treating ALF.

Menstrual Blood-Derived Mesenchymal Stem Cells: Women's Attitudes, Willingness, and Barriers to Donation of Menstrual Blood

Background: Menstrual blood contains mesenchymal stem cells (MenSC), considered a potential "off-the-shelf" treatment for a range of diseases and medical conditions. Samples of menstrual blood can be collected painlessly, inexpensively, and as frequently as every month for cell therapy. While there has been considerable previous research into the clinical advantages of MenSC, there is currently little understanding of potential donors' attitudes regarding menstrual blood donation and MenSC. Methods: One hundred women 18 years of age or over were surveyed to understand attitudes and potential barriers to menstrual blood donation. The questionnaire assessed participant age and brief medical history (giving birth, donating blood, donating stem cells), menstrual experience (period rating, preferred menstrual hygiene products), and whether participants would donate MenSC or accept MenSC therapy. Results: MenSC was met with a generally positive response, with 78% of menstruating women willing to donate menstrual blood. No significant relationship was recognized between willingness to donate menstrual blood with age, history of childbirth or blood donation, menstruation perception, and preferred menstrual hygiene product. Women rated their period experience better after being made aware of the ability to donate menstrual blood, meaning MenSC therapy can be beneficial for donors as well as patients. Conclusions: Considering women's attitudes to MenSC and donation of menstrual blood, the future of MenSC therapy is positive; women are generally willing to donate menstrual blood, independent of age, perception of periods, and history of childbirth and blood donation.

High-yield isolation of menstrual blood-derived endometrial stem cells by direct red blood cell lysis treatment

Recently, menstrual blood-derived endometrial stem cells (MenSCs) have become attractive for stem cell based therapy due to their abundance, easy and non-invasive extraction and isolation process, high proliferative capacity, and multi-lineage differentiation potential. MenSC-based therapies for various diseases are being extensively researched. However, the high death rate and poor engraftment in sites of damaged tissues reduce the therapeutic value of these stem cells for transplantation. In theory, periodic stem cell transplantation is an alternative strategy to overcome the challenge of the loss of beneficial stem cell-derived effects due to the rapid disappearance of the stem cells in vivo. However, periodic stem cell transplantation requires sufficient amounts of the desired stem cells with a low number of subculture passages. Our previous results have demonstrated that primary MenSCs mainly reside in the deciduous endometrium, and considerable amounts of deciduous endometrium intertwined with menstrual blood clots were discarded after conventional density gradient centrifugation (DGC). Therefore, the aim of this study was to determine whether primary MenSCs exist in the sedimentation of the deciduous endometrium after DGC and further to evaluate the isolation of MenSCs by direct red blood cell lysis treatment. As expected, our results confirmed that substantial amounts of primary MenSCs still remain in the sedimentation after DGC and indicated that MenSC isolation by directly lysing the red blood cells not only guaranteed substantial amounts of superior MenSCs with a low number of subculture passages, but also was time efficient and economical, providing a solid support for extensive clinical application.

Summary: MenSC isolation by directly lysing the red blood cells not only guarantees substantial amounts of superior MenSCs with low passage number, but also is time efficient and economical.

A silk fibroin/decellularized extract of Wharton's jelly hydrogel intended for cartilage tissue engineering

A hybrid hydrogel was obtained from decellularized extract from Wharton's jelly (DEWJ) and silk fibroin (SF) and characterized for cartilage tissue engineering. Wharton's jelly was used due to its similarity with articular cartilage in extracellular matrix composition. Also, silk fibroin has good mechanical properties which make this construct appropriate for cartilage repair. Decellularization of Wharton's jelly was verified by DAPI staining, DNA quantification, and PCR analysis. Then, the biochemical composition of DEWJ was determined by ELISA kits for total proteins, collagens, sulfated glycosaminoglycans (sGAG), and transforming growth factor β1 (TGF-β1). After fabricating pure SF and SF/DEWJ hybrid hydrogels, their physical and mechanical properties were characterized by FESEM, Fourier-transform infrared spectroscopy (FTIR) and rheological assays (amplitude and frequency sweeps). Furthermore, cell viability and proliferation were assessed by MTT assay. The results have shown that DEWJ in hybrid hydrogels enhances mechanical properties of the construct relative to pure SF hydrogels. Also, this extract at its 40% concentration in culture media and 20% or 40% concentrations in SF/DEWJ hybrid hydrogels significantly increases population of the cells compared to control and pure SF hydrogel after 7 days. In conclusion, this study proposes the potential of SF/DEWJ hybrid hydrogels for cartilage tissue engineering applications.

Stem cells on regenerative and reproductive science in domestic animals

Stem cells are undifferentiated and self-renewable cells that present new possibilities for both regenerative medicine and the understanding of early mammalian development. Adult multipotent stem cells are already widely used worldwide in human and veterinary medicine, and their therapeutic signalling, particularly with respect to immunomodulation, and their trophic properties have been intensively studied. The derivation of embryonic stem cells (ESCs) from domestic species, however, has been challenging, and the poor results do not reflect the successes obtained in mouse and human experiments. More recently, the generation of induced pluripotent stem cells (iPSCs) via the forced expression of specific transcription factors has been demonstrated in domestic species and has introduced new potentials in regenerative medicine and reproductive science based upon the ability of these cells to differentiate into a variety of cells types in vitro. For example, iPSCs have been differentiated into primordial germ-like cells (PGC-like cells, PGCLs) and functional gametes in mice. The possibility of using iPSCs from domestic species for this purpose would contribute significantly to reproductive technologies, offering unprecedented opportunities to restore fertility, to preserve endangered species and to generate transgenic animals for biomedical applications. Therefore, this review aims to provide an updated overview of adult multipotent stem cells and to discuss new possibilities introduced by the generation of iPSCs in domestic animals, highlighting the possibility of generating gametes in vitro via PGCL induction.

Sources and Clinical Applications of Mesenchymal Stem Cells: State-of-the-art review

First discovered by Friedenstein in 1976, mesenchymal stem cells (MSCs) are adult stem cells found throughout the body that share a fixed set of characteristics. Discovered initially in the bone marrow, this cell source is considered the gold standard for clinical research, although various other sources-including adipose tissue, dental pulp, mobilised peripheral blood and birth-derived tissues-have since been identified. Although similar, MSCs derived from different sources possess distinct characteristics, advantages and disadvantages, including their differentiation potential and proliferation capacity, which influence their applicability. Hence, they may be used for specific clinical applications in the fields of regenerative medicine and tissue engineering. This review article summarises current knowledge regarding the various sources, characteristics and therapeutic applications of MSCs.

Cytogenetic and Transcriptomic Analysis of Human Endometrial MSC Retaining Proliferative Activity after Sublethal Heat Shock

Temperature is an important exogenous factor capable of leading to irreversible processes in the vital activity of cells. However, the long-term effects of heat shock (HS) on mesenchymal stromal cells (MSC) remain unstudied. We investigated the karyotype and DNA repair drivers and pathways in the human endometrium MSC (eMSC) survived progeny at passage 6 after sublethal heat stress (sublethal heat stress survived progeny (SHS-SP)). G-banding revealed an outbreak of random karyotype instability caused by chromosome breakages and aneuploidy. Molecular karyotyping confirmed the random nature of this instability. Transcriptome analysis found homologous recombination (HR) deficiency that most likely originated from the low thermostability of the AT-rich HR driving genes. SHS-SP protection from transformation is provided presumably by low oncogene expression maintained by tight co-regulation between thermosensitive HR drivers BRCA, ATM, ATR, and RAD51 (decreasing expression after SHS), and oncogenes mTOR, MDM2, KRAS, and EGFR. The cancer-related transcriptomic features previously identified in hTERT transformed MSC in culture were not found in SHS-SP, suggesting no traits of malignancy in them. The entrance of SHS-SP into replicative senescence after 25 passages confirms their mortality and absence of transformation features. Overall, our data indicate that SHS may trigger non-tumorigenic karyotypic instability due to HR deficiency and decrease of oncogene expression in progeny of SHS-survived MSC. These data can be helpful for the development of new therapeutic approaches in personalized medicine.

Promotion of excisional wound repair by a menstrual blood-derived stem cell-seeded decellularized human amniotic membrane

This is the first study demonstrating the efficacy of menstrual blood-derived stem cell (MenSC) transplantation via decellularized human amniotic membrane (DAM), for the promotion of skin excisional wound repair. The DAM was seeded with MenSCs at the density of 3 × 10⁴ cells/cm² and implanted onto a rat's 1.50 × 1.50 cm² full-thickness excisional wound defect. The results of wound closure and histopathological examinations demonstrated that the MenSC-seeded DAM could significantly improve the wound healing compared with DAM-treatment. All in all, our data indicated that the MenSCs can be a potential source for cell-based therapies to regenerate skin injuries.

Stem cell-based therapy for Parkinson's disease with a focus on human endometrium-derived mesenchymal stem cells

Parkinson's disease (PD) as an increasing clinical syndrome is a multifunctional impairment with systemic involvement. At present, therapeutic approaches such as l-3,4-dihydroxy-phenylalanine replacement therapy, dopaminergic agonist administration, and neurosurgical treatment intend to relieve PD symptoms which are palliative and incompetent in counteracting PD progression. These mentioned therapies have not been able to replace the lost cells and they could not effectively slow down the relentless neurodegenerative process. Till now, there is a lack of eligible treatment for PD, and stem cells therapy recently has been considered for PD treatment. In this review, we demonstrate how human stem cell technology especially human endometrium-derived stem cells have made advancement as a therapeutic source for PD compared with other treatments.

Evaluation of Vav3.1 as prognostic marker in endometrial cancer

PURPOSE

Vav3 is a guanine nucleotide exchange factor that regulates the activity of Rho/Rac family GTPases. In a study on ovarian cancer, we recently demonstrated pronounced prognostic and predictive value of Vav3.1, a specific truncation variant of the parental Vav3 gene. Here, we sought to investigate the role of Vav3.1 in the most prevalent gynecological tumor entity, endometrial cancer.

METHODS

Vav3.1 transcript levels were determined in a large cohort of endometrial cancer patients using variant-specific PCR (n = 239), and non-malignant endometrial tissue served as control (n = 26). Expression levels of Vav3.1 were stratified according to established clinicopathological characteristics and correlated to long-term patient survival (average follow-up of > 7.5 years). Type 1 and type 2 cancers were separately investigated.

RESULTS

While Vav3.1 was markedly overexpressed in endometrial cancer tissue, we could not detect associations with clinical parameters related to prognosis, such as FIGO stage and tumor grade. Kaplan-Meier estimators of different measures of survival failed to show prognostic significance of Vav3.1 in endometrial cancer. Lack of prognostic value was observed for both type 1 and type 2 cancers.

CONCLUSIONS

Our study shows that Vav3.1 is not suited as a marker of cancer progression and/or treatment response in endometrial cancer. Feasibility and potential benefit of targeting Vav3.1 in endometrial cancer needs to be evaluated in future studies, proceeding from its clear, roughly ten-fold, induction in the malignant endometrium.

Stem cell therapy in Asherman syndrome and thin endometrium: Stem cell- based therapy

The endometrium is one of the essential components of the uterus. The endometrium of human is a complex and dynamic tissue, which undergoes periods of growth and turn over during any menstrual cycle. Stem cells are initially undifferentiated cells that display a wide range of differentiation potential with no distinct morphological features. Stem cell therapy method recently has become a novel procedure for treatment of tissue injury and fibrosis in response to damage. Currently, there is massive interest in stem cells as a novel treatment method for regenerative medicine and more specifically for the regeneration of human endometrium disorder like Asherman syndrome (AS) and thin endometrium. AS also known as intrauterine adhesion (IUA) is a uterine disorder with the aberrant creation of adhesions within the uterus and/or cervix. Patients with IUA are significantly associated with menstrual abnormalities and suffer from pelvic pain. In addition, IUA might prevent implantation of the blastocyst, impair the blood supply to the uterus and early fetus, and finally result in the recurrent miscarriage or infertility in the AS patients. It has been evidenced that the transplantation of different stem cells with a diverse source in the endometrial zone had effects on endometrium such as declined the fibrotic area, an elevated number of glands, stimulated angiogenesis, the enhanced thickness of the endometrium, better formed tissue construction, protected gestation, and improved pregnancy rate. This study presents a summary of the investigations that indicate the key role of stem cell therapy in regeneration and renovation of defective parts.

Biological characteristics of human menstrual blood-derived endometrial stem cells

Successful isolation of human endometrial stem cells from menstrual blood, namely menstrual blood-derived endometrial stem cells (MenSCs), has provided enticing alternative seed cells for stem cell-based therapy. MenSCs are enriched in the self-regenerative tissue, endometrium, which shed along the periodic menstrual blood and thus their acquisition involves no physical invasiveness. However, the impact of the storage duration of menstrual blood prior to stem cell isolation, the age of the donor, the number of passages on the self-renewing of MenSCs, the paracrine production of biological factors in MenSCs and expression of adhesion molecules on MenSCs remain elusive. In this study, we confirmed that MenSCs reside in shedding endometrium, and documented that up to 3 days of storage at 4°C has little impact on MenSCs, while the age of the donor and the number of passages are negatively associated with proliferation capacity of MenSCs. Moreover, we found that MenSCs were actually immune-privileged and projected no risk of tumour formation. Also, we documented a lung- and liver-dominated, spleen- and kidney-involved organic distribution profile of MenSC 3 days after intravenous transfer into mice. At last, we suggested that MenSCs may have potentially therapeutic effects on diseases through paracrine effect and immunomodulation.

Effects of platelet-rich plasma on the activity of human menstrual blood-derived stromal cells in vitro

Background

Human menstrual blood-derived stromal cells (MenSCs) are highly proliferative and show multiple differentiation capacity. The convenience and non-invasiveness make MenSC a novel cell source for regenerative medicine applications. Platelet-rich plasma (PRP) contains abundant growth factors which are beneficial to wound healing. However, the influence of PRP on MenSCs remains elusive. Here, we evaluated the role of PRP in MenSCs proliferation and assessed the effects of PRP on endometrial receptivity regulation in vitro.

Methods

MenSCs cultured with 10% activated PRP were compared with those cultured with 10% fetal bovine serum (FBS). Differences in cell proliferation, differentiation, and endometrial receptivity-related gene expression were evaluated.

Results

Notably, 10% activated PRP significantly promoted MenSCs proliferation and adipogenic/osteogenic differentiation while suppressing apoptosis. Expression of the mesenchymal stem cells (MSCs) marker CD105 and the perivascular markers SUSD2 and CD146 were elevated after PRP treatment. Moreover, short-term PRP stimulation activated the phosphorylation of Akt and signal transducer and activator of transcription 3 (STAT3) pathways, upregulated expression of FoxO1, LIF, and IL1-β, and downregulated IL-6.

Conclusions

In summary, PRP could promote MenSC proliferation, markedly accelerate cell stemness, and evaluate MenSC functions by enhancing the expression of angiogenesis and endometrial receptivity markers, suggesting its potential use as a promising supplement for MenSCs in endometrial regenerative medicine. Our results provide a theoretical basis for the clinical application of co-transplantation of PRP combined with MenSCs.

Electronic supplementary material

The online version of this article (10.1186/s13287-018-0795-3) contains supplementary material, which is available to authorized users.

Human mesenchymal stem cells in spheroids improve fertility in model animals with damaged endometrium

BACKGROUND

Asherman's syndrome (AS) is one of the gynecological disorders caused by the destruction of the endometrium. For some cases of AS available surgical methods and hormonal therapy are ineffective. Stem cell transplantation may offer a potential alternative for AS cure.

METHODS

Human endometrial mesenchymal stem cells (eMSC) organized in spheroids were transplanted in rats with damaged endometrium modeled on AS. Treatment response was defined as pregnancy outcome and litter size.

RESULTS

Application of eMSC in spheroids significantly improved the rat fertility with the AS model. eMSC organized in spheroids retain all properties of eMSC in monolayer: growth characteristics, expression of CD markers, and differentiation potential. Synthesis of angiogenic and anti-inflammatory factors drastically increased in eMSC assembled into spheroids.

CONCLUSIONS

Human endometrial mesenchymal stem cells (eMSC) can be successfully applied for Asherman's syndrome (AS) treatment in the rat model. eMSC organized in spheroids were more therapeutically effective than the cells in monolayer. After transplantation of eMSC in spheroids the pregnancy outcome and litter size in rats with AS was higher than in rats that received autologous rat bone marrow cells. It suggests the therapeutic plausibility of heterologous eMSC in case of failure to use autologous cells.

Human endometrial stem cells: High-yield isolation and characterization

BACKGROUND

Menstrual blood is only recently and still poorly studied, but it is an abundant and noninvasive source of highly proliferative mesenchymal stromal cells (MSCs). However, no appropriate isolation method has been reported due to its high viscosity and high content of clots and desquamated epithelium.

METHODS

We studied three different isolation approaches and their combinations: ammonium-containing lysing buffer, distilled water and gradient-density centrifugation. We tested the proliferative capacity, morphology, surface markers and pluripotency of the resulting cells.

RESULTS

Our isolation method yields up to four million nucleated cells per milliliter of initial blood, of which about 0.2-0.3% are colony-forming cells expressing standard mesenchymal markers CD90, CD105 and CD73, but not expressing CD45, CD34, CD117, CD133 or HLA-G. The cells have high proliferative potential (doubling in 26 h) and the ability to differentiate into adipocytes and osteocytes. Early endometrial MSCs (eMSCs) express epithelial marker cytokeratin 7 (CK7). CK7 is easily induced in later passages in a prohepatic environment. We show for the first time that a satisfactory and stable yield of eMSCs is observed throughout the whole menstrual period (5 consecutive days) of a healthy woman.

DISCUSSION

The new cost/yield adequate method allows isolation from menstrual blood a relatively homogenous pool of highly proliferative MSCs, which seem to be the best candidates for internal organ therapy due to their proepithelial background (early expression of CK7 and its easy induction in later passages) and for mass cryobanking due to their high yield and availability.

Isolation, culture, characterization, and osteogenic differentiation of canine endometrial mesenchymal stem cell

Aim

In this study, the canine endometrium tissue is characterized for its stem cell properties such as adherence to tissue culture plate (plasticity), short population doubling time, serial clonal passaging, long-term culturing properties, stem cell marker expression, and multilineage differentiation potential.

Materials and Methods

The present work describes a novel isolation protocol for obtaining mesenchymal stem cells from the uterine endometrium and is compared with cells derived from umbilical cord matrix as a positive control. These cells are clonogenic, can undergo several population doublings in vitro, and can be differentiated to the osteocytes in mature mesenchymal tissues when grown in osteogenic differentiation media as detected by Alizarin Red-S staining.

Results

It is reported for the first time that the cells derived from the canine endometrium (e-multipotent stem cells [MSCs]) were able to differentiate into a heterologous cell type: Osteocytes, thus demonstrating the presence of MSCs. Thus, the endometrium may be told as a potential source of MSCs which can be used for various therapeutic purposes.

Conclusion

The endometrium can be used as a potential source of MSCs, which can be used for various therapeutic purposes.

Identification of perivascular and stromal mesenchymal stem/progenitor cells in porcine endometrium

Mammalian uterus contains a population of mesenchymal stem/progenitor cells that likely contribute to endometrial regeneration during each reproductive cycle. In human and mouse, they reside in perivascular, epithelial and stromal compartments of the endometrial functionalis and basalis. Here, we aimed to identify tissue resident cells expressing mesenchymal stem cell markers CD29, CD44, CD90, CD105, CD140b and CD146 in the porcine endometrium. We used single immunofluorescence and Western blotting. Each of these markers was detected in small cells surrounding endometrial blood vessels. CD105 and CD146 were also expressed in single stromal cells. A few stromal and perivascular cells showed the presence of pluripotency marker Oct4 in the cytoplasm, but not in the nucleus, which may imply they are not truly pluripotent. Endometrial cell cultures were examined for the expression of CD29, CD44, CD90, CD105 and CD140b proteins and tested in wound-healing assay and culture model of chemotaxis. In conclusion, our results demonstrate perivascular location of prospective mesenchymal stem/progenitor cells in the porcine endometrium and may suggest that stromal CD105⁺ and CD146⁺ cells represent more mature precursors originating from their perivascular ancestors.

Characteristics of Human Endometrium-Derived Mesenchymal Stem Cells and Their Tropism to Endometriosis

Human endometrial tissue has become an attractive source of mesenchymal stem cells (MSCs) for cell-based therapies because these MSCs can be easily harvested and have tumour tropism as well as reduced immunogenic and inflammatory properties. Our study aimed to obtain and characterise human endometrial mesenchymal stem cells (EMSCs) and assess their endometriosis tropism. EMSCs were successfully isolated from the endometrium of women undergoing laparoscopy for idiopathic infertility. The EMSCs presented a fibroblast-like morphology during culture. Flow cytometry analyses showed that the cells were positive for the specific stem cell markers CD73, CD90, CD105, CD166, and HLA-ABC (major histocompatibility complex class I (MHC I)) but negative for CD14, CD34, CD45, and HLA-DR (MHC II). Reverse transcription polymerase chain reaction results showed that the EMSCs expressed the stem cell marker OCT4. The EMSCs could differentiate into osteocytes, adipocytes, and chondrocytes under certain conditions. The EMSCs had a high tropism to endometriosis without tumourigenicity. This study enhances the possibility of using EMSCs as drug carriers in human cell-based therapies. Meanwhile, future research could also focus on developing targeted therapies for endometriosis.

Current Bioengineering and Regenerative Strategies for the Generation of Kidney Grafts on Demand

Currently in the USA, one name is added to the organ transplant waiting list every 15 min. As this list grows rapidly, fewer than one-third of waiting patients can receive matched organs from donors. Unfortunately, many patients who require a transplant have to wait for long periods of time, and many of them die before receiving the desired organ. In the USA alone, over 100,000 patients are waiting for a kidney transplant. However, it is a problem that affects around 6% of the word population. Therefore, seeking alternative solutions to this problem is an urgent work. Here, we review the current promising regenerative technologies for kidney function replacement. Despite many approaches being applied in the different ways outlined in this work, obtaining an organ capable of performing complex functions such as osmoregulation, excretion or hormone synthesis is still a long-term goal. However, in the future, the efforts in these areas may eliminate the long waiting list for kidney transplants, providing a definitive solution for patients with end-stage renal disease.

Mesenchymal stem cells: a promising tool for targeted gene therapy of endometriosis

Endometriosis is a leading, benign gynecological disorder around the world. Last few years have witnessed tremendous growth in the field of endometriosis and endometrial stem-cell research. Despite advancements in the biology and pathology of endometriosis, disease recurrence is still an enigma. Gene therapy holds promise in treating many pathologic conditions including endometriosis. Mesenchymal stem cells (MSCs) serve as ideal candidates for regenerative medicine and cell-based therapies. Owing to their specificity to the endometrium, residing endometrial MSC populations could be utilized as ideal candidates for targeting endometrial disorders. Recently, we demonstrated their flexibility for gene transduction using adenoviral vectors. The review highlights the potential of endometrial MSCs in devising targeted gene therapies for endometriosis.

Successful derivation of xeno-free mesenchymal stem cell lines from endometrium of infertile women

Transplantation of mesenchymal stem cells (MSC) can effectively repair endometrial deficiencies, including infertile patients with a problem of inadequate endometrium thickness. Although, MSC derived from different organ sources have a similarity of MSC specific characteristics, endometrial stem cells (EMSC) are temporally regulated throughout the menstrual cycle in a micro-environmental niche found only in endometrial tissue. Given the micro-environment niche, developing treatments for endometrial disorders with EMSC should be a top priority. To provide EMSC that afford safety for therapeutic usage, we have established a completely xeno-free EMSC line derivation protocol using human allogenic umbilical cord serum instead of animal derived reagents, and proved that it is feasible to generate xeno-free EMSC lines from infertile patient donors using these conditions. Our results demonstrate the successful derivation of xeno-free EMSC lines from 10 out of 10 infertile patients. The resultant xeno-free EMSC lines showed typical MSC morphology, phenotypic markers, differentiation capacity, telomere length and normal karyotypes. They showed superior proliferation capability, but lower expression of proto-oncogenes, to the lines generated under standard (animal derived reagents) culture. Biosafety of xeno-free EMSC lines also displayed in retention of immunosuppressive ability, epigenetic stability by imprinted genes expression, proto-oncogenes expression and no mutation of specific codon on p53 tumor suppressor gene. Taken together, these data indicate that our cells may be safe for clinical use. In conclusion, we have succeeded in establishing completely xeno-free EMSC lines and demonstrate for the first time that autogenic and xeno-free EMSC lines can be generated from infertile women.

Bovine endometrial cells: a source of mesenchymal stem/progenitor cells

Endometrial mesenchymal stem/progenitor cells (eMSCs) are multipotent cells known to modulate the immune system and have clinical application for human and animal health. This makes these bovines cells attractive for dual use as cellular therapy and experimental model. The aim of this study was to isolate, evaluate the differentiation potential, immunophenotypic and immunocytochemistry characteristics, chromosomal stability, cloning efficiency, and cryopreservation response of bovine eMSCs collected in two phases of the estrous cycle. For this, cells were isolated and submitted to differentiation for adipogenic and osteogenic lineage. The cells were then characterized by flow cytometer (FC) (vimentin, CD29, CD44, MHC-II, CD34) and immunocytochemistry (vimentin, pan-cytokeratin, CD44) and submitted to cytogenetic and cloning efficiency assay. The cells were also cryopreserved using two different medium of cryopreservation and analyzed by FC for viability, necrosis, late-apoptosis + necrosis, and initial apoptosis rates before and after cryopreservation. We obtained homogeneous cell populations which have fibroblastic morphology and adherence to plastic. These cells expressed high levels of markers CD29, CD44, and vimentin, low expression levels for CD34 and no MHC-II. The cells were chromosomally stable (2n = 60) with high cloning efficiency and no difference (P > 0.05) between medium of cryopreservation or phase was observed after thawing. We showed the presence and differentiation potential of bovine eMSCs, with chromosomal stability and great response to cryopreservation with both medium, which has implications for build biobanks or development of new therapeutic approaches to combat uterine diseases or to study.

Autologous menstrual blood-derived stromal cells transplantation for severe Asherman's syndrome

STUDY QUESTION

Does autologous transplantation of menstrual blood-derived stromal cells (menSCs) regenerate endometrium to support pregnancy in patients with severe Asherman's syndrome (AS)?

SUMMARY ANSWER

Autologous menSCs transplantation significantly increases endometrial thickness (ET) for women with severe AS.

WHAT IS KNOWN ALREADY

AS is a major cause of secondary infertility in women. Cell transplantation has been tried in a few clinical cases with encouraging results.

STUDY DESIGN, SIZE, DURATION

In this experimental, non-controlled and prospective 3-year clinical study involving seven patients with AS, autologous menSCs were isolated and cultured from menstrual blood of each patient within ~2 weeks and then transplanted back into their uterus. Endometrial growth and pregnancy were assessed after cell therapy.

PARTICIPANTS/MATERIALS, SETTING, METHOD

Infertile women, aged 20-40 years, diagnosed with severe AS (Grade III-V) by hysteroscopy and with menstrual fluid were recruited at the Shengjing Hospital affiliated to China Medical University. Autologous menSCs transplantation was conducted followed by HRT. Endometrial thickness was monitored with frozen embryo transfer (FET) as needed.

MAIN RESULTS AND THE ROLE OF CHANCE

We successfully cultured menSCs from seven patients and transferred the autologous cells back to their uterus. Our results showed that the ET was significantly (P = 0.0002) increased to 7 mm in five women, which ensured embryo implantation. Four patients underwent FET and two of them conceived successfully. One patient had spontaneous pregnancy after second menSCs transplantation.

LIMITATIONS, REASONS FOR CAUTION

Limited sample size, lack of rigorous controls or knowledge of underlying mechanism.

WIDER IMPLICATIONS OF THE FINDINGS

Autologous menSCs transplantation is a potential option for treating women with severe AS.

STUDY FUNDING/COMPETING INTERESTS

This study was supported by Liaoning Provincial Science and Technology Program. The sponsor and authors declare no conflicts of interest.

TRIAL REGISTRATION NUMBER

Registered in the Chinese Clinical Trial Registry (ChiCTR-ONB-15007464).

Secreted trophic factors of mesenchymal stem cells support neurovascular and musculoskeletal therapies

Adult mesenchymal stem cells (MSCs) represent a subject of intense experimental and biomedical interest. Recently, trophic activities of MSCs have become the topic of a number of revealing studies that span both basic and clinical fields. In this review, we focus on recent investigations that have elucidated trophic mechanisms and shed light on MSC clinical efficacy relevant to musculoskeletal applications. Innate differences due to MSC sourcing may play a role in the clinical utility of isolated MSCs. Pain management, osteochondral, nerve, or blood vessel support by MSCs derived from both autologous and allogeneic sources have been examined. Recent mechanistic insights into the trophic activities of these cells point to ultimate regulation by nitric oxide, nuclear factor-kB, and indoleamine, among other signaling pathways. Classic growth factors and cytokines-such as VEGF, CNTF, GDNF, TGF-β, interleukins (IL-1β, IL-6, and IL-8), and C-C ligands (CCL-2, CCL-5, and CCL-23)-serve as paracrine control molecules secreted or packaged into extracellular vesicles, or exosomes, by MSCs. Recent studies have also implicated signaling by microRNAs contained in MSC-derived exosomes. The response of target cells is further regulated by their microenvironment, involving the extracellular matrix, which may be modified by MSC-produced matrix metalloproteinases (MMPs) and tissue inhibitor of MMPs. Trophic activities of MSCs, either resident or introduced exogenously, are thus intricately controlled, and may be further fine-tuned via implant material modifications. MSCs are actively being investigated for the repair and regeneration of both osteochondral and other musculoskeletal tissues, such as tendon/ligament and meniscus. Future rational and effective MSC-based musculoskeletal therapies will benefit from better mechanistic understanding of MSC trophic activities, for example using analytical "-omics" profiling approaches.

Reproductive biology, stem cells biotechnology and regenerative medicine: a 1-day national symposium held at Shahid Sadoughi University of Medical Sciences

This paper summarizes the proceedings of a 1 day national symposium entitled “Reproductive biology, stem cells biotechnology and regenerative medicine” held at Shahid Sadoughi University of Medical Sciences, Yazd, Iran on 3^rd March 2016. Here, we collected the papers that presented and discussed at this meeting by specialists that currently researched about the overlaps of the fields of reproductive biology and stem cells and their applications in regenerative medicine.

Engineered Biomaterials to Enhance Stem Cell-Based Cardiac Tissue Engineering and Therapy

Cardiovascular disease is a leading cause of death worldwide. Since adult cardiac cells are limited in their proliferation, cardiac tissue with dead or damaged cardiac cells downstream of the occluded vessel does not regenerate after myocardial infarction. The cardiac tissue is then replaced with nonfunctional fibrotic scar tissue rather than new cardiac cells, which leaves the heart weak. The limited proliferation ability of host cardiac cells has motivated investigators to research the potential cardiac regenerative ability of stem cells. Considerable progress has been made in this endeavor. However, the optimum type of stem cells along with the most suitable matrix-material and cellular microenvironmental cues are yet to be identified or agreed upon. This review presents an overview of various types of biofunctional materials and biomaterial matrices, which in combination with stem cells, have shown promises for cardiac tissue replacement and reinforcement. Engineered biomaterials also have applications in cardiac tissue engineering, in which tissue constructs are developed in vitro by combining stem cells and biomaterial scaffolds for drug screening or eventual implantation. This review highlights the benefits of using biomaterials in conjunction with stem cells to repair damaged myocardium and give a brief description of the properties of these biomaterials that make them such valuable tools to the field.