Fetal stem cells from extra-embryonic tissues: do not discard

Wharton's jelly mesenchymal stem cells: Future regenerative medicine for clinical applications in mitigation of radiation injury

Wharton's jelly mesenchymal stem cells (WJ-MSCs) are gaining significant attention in regenerative medicine for their potential to treat degenerative diseases and mitigate radiation injuries. WJ-MSCs are more naïve and have a better safety profile, making them suitable for both autologous and allogeneic transplantations. This review highlights the regenerative potential of WJ-MSCs and their clinical applications in mitigating various types of radiation injuries. In this review, we will also describe why WJ-MSCs will become one of the most probable stem cells for future regenerative medicine along with a balanced view on their strengths and weaknesses. Finally, the most updated literature related to both preclinical and clinical usage of WJ-MSCs for their potential application in the regeneration of tissues and organs will also be compiled.

Silica nanoparticles enhance interfacial self-adherence of a multi-layered extracellular matrix scaffold for vascular tissue regeneration

PURPOSE

Based on the clinical need for grafts for vascular tissue regeneration, our group developed a customizable scaffold derived from the human amniotic membrane. Our approach consists of rolling the decellularized amniotic membrane around a mandrel to form a multilayered tubular scaffold with tunable diameter and wall thickness. Herein, we aimed to investigate if silica nanoparticles (SiNP) could enhance the adhesion of the amnion layers within these rolled grafts.

METHODS

To test this, we assessed the structural integrity and mechanical properties of SiNP-treated scaffolds. Mechanical tests were repeated after six months to evaluate adhesion stability in aqueous environments.

RESULTS

Our results showed that the rolled SiNP-treated scaffolds maintained their tubular shape upon hydration, while non-treated scaffolds collapsed. By scanning electron microscopy, SiNP-treated scaffolds presented more densely packed layers than untreated controls. Mechanical analysis showed that SiNP treatment increased the scaffold's tensile strength up to tenfold in relation to non-treated controls and changed the mechanism of failure from interfacial slipping to single-point fracture. The nanoparticles reinforced the scaffolds both at the interface between two distinct layers and within each layer of the extracellular matrix. Finally, SiNP-treated scaffolds significantly increased the suture pullout force in comparison to untreated controls.

CONCLUSION

Our study demonstrated that SiNP prevents the unraveling of a multilayered extracellular matrix graft while improving the scaffolds' overall mechanical properties. In addition to the generation of a robust biomaterial for vascular tissue regeneration, this novel layering technology is a promising strategy for a number of bioengineering applications.

Beyond Vision: An Overview of Regenerative Medicine and Its Current Applications in Ophthalmological Care

Regenerative medicine (RM) has emerged as a promising and revolutionary solution to address a range of unmet needs in healthcare, including ophthalmology. Moreover, RM takes advantage of the body's innate ability to repair and replace pathologically affected tissues. On the other hand, despite its immense promise, RM faces challenges such as ethical concerns, host-related immune responses, and the need for additional scientific validation, among others. The primary aim of this review is to present a high-level overview of current strategies in the domain of RM (cell therapy, exosomes, scaffolds, in vivo reprogramming, organoids, and interspecies chimerism), centering around the field of ophthalmology. A search conducted on clinicaltrials.gov unveiled a total of at least 209 interventional trials related to RM within the ophthalmological field. Among these trials, there were numerous early-phase studies, including phase I, I/II, II, II/III, and III trials. Many of these studies demonstrate potential in addressing previously challenging and degenerative eye conditions, spanning from posterior segment pathologies like Age-related Macular Degeneration and Retinitis Pigmentosa to anterior structure diseases such as Dry Eye Disease and Limbal Stem Cell Deficiency. Notably, these therapeutic approaches offer tailored solutions specific to the underlying causes of each pathology, thus allowing for the hopeful possibility of bringing forth a treatment for ocular diseases that previously seemed incurable and significantly enhancing patients' quality of life. As advancements in research and technology continue to unfold, future objectives should focus on ensuring the safety and prolonged viability of transplanted cells, devising efficient delivery techniques, etc.

Arouse potential stemness: Intrinsic and acquired stem cell therapeutic strategies for advanced liver diseases

Liver diseases are a major health issue, and prolonged liver injury always progresses. Advanced liver disorders impair liver regeneration. Millions of patients die yearly worldwide, even with the available treatments of liver transplantation and artificial liver support system. With its abundant cell resources and significant differentiative potential, stem cell therapy is a viable treatment for various disorders and offers hope to patients waiting for orthotopic liver transplantation. Considering such plight, stem cell therapeutic strategies deliver hope to the patients. Moreover, we conclude intrinsic and acquired perspectives based on stem cell sources. The properties and therapeutic uses of these stem cells' specific types or sources were then reviewed. Owing to the recent investigations of the above cells, a safe and effective therapy will emerge for advanced liver diseases soon.

Multipotent fetal stem cells in reproductive biology research

Due to the limited accessibility of the in vivo situation, the scarcity of the human tissue, legal constraints, and ethical considerations, the underlying molecular mechanisms of disorders, such as preeclampsia, the pathological consequences of fetomaternal microchimerism, or infertility, are still not fully understood. And although substantial progress has already been made, the therapeutic strategies for reproductive system diseases are still facing limitations. In the recent years, it became more and more evident that stem cells are powerful tools for basic research in human reproduction and stem cell-based approaches moved into the center of endeavors to establish new clinical concepts. Multipotent fetal stem cells derived from the amniotic fluid, amniotic membrane, chorion leave, Wharton´s jelly, or placenta came to the fore because they are easy to acquire, are not associated with ethical concerns or covered by strict legal restrictions, and can be banked for autologous utilization later in life. Compared to adult stem cells, they exhibit a significantly higher differentiation potential and are much easier to propagate in vitro. Compared to pluripotent stem cells, they harbor less mutations, are not tumorigenic, and exhibit low immunogenicity. Studies on multipotent fetal stem cells can be invaluable to gain knowledge on the development of dysfunctional fetal cell types, to characterize the fetal stem cells migrating into the body of a pregnant woman in the context of fetomaternal microchimerism, and to obtain a more comprehensive picture of germ cell development in the course of in vitro differentiation experiments. The in vivo transplantation of fetal stem cells or their paracrine factors can mediate therapeutic effects in preeclampsia and can restore reproductive organ functions. Together with the use of fetal stem cell-derived gametes, such strategies could once help individuals, who do not develop functional gametes, to conceive genetically related children. Although there is still a long way to go, these developments regarding the usage of multipotent fetal stem cells in the clinic should continuously be accompanied by a wide and detailed ethical discussion.

Human Fetal Cartilage-Derived Progenitor Cells Exhibit Anti-Inflammatory Effect on IL-1β-Mediated Osteoarthritis Phenotypes In Vitro

BACKGROUND

In this study, we have investigated whether human fetal cartilage progenitor cells (hFCPCs) have anti-inflammatory activity and can alleviate osteoarthritis (OA) phenotypes in vitro.

METHODS

hFCPCs were stimulated with various cytokines and their combinations and expression of paracrine factors was examined to find an optimal priming factor. Human chondrocytes or SW982 synoviocytes were treated with interleukin-1β (IL-1β) to produce OA phenotype, and co-cultured with polyinosinic-polycytidylic acid (poly(I-C))-primed hFCPCs to address their anti-inflammatory effect by measuring the expression of OA-related genes. The effect of poly(I-C) on the surface marker expression and differentiation of hFCPCs into 3 mesodermal lineages was also examined.

RESULTS

Among the priming factors tested, poly(I-C) (1 µg/mL) most significantly induced the expression of paracrine factors such as indoleamine 2,3-dioxygenase, histocompatibility antigen, class I, G, tumor necrosis factor- stimulated gene-6, leukemia inhibitory factor, transforming growth factor-β1 and hepatocyte growth factor from hFCPCs. In the OA model in vitro, co-treatment of poly(I-C)-primed hFCPCs significantly alleviated IL-1β-induced expression of inflammatory factors such as IL-6, monocyte chemoattractant protein-1 and IL-1β, and matrix metalloproteinases in SW982, while it increased the expression of cartilage extracellular matrix such as aggrecan and collagen type II in human chondrocytes. We also found that treatment of poly(I-C) did not cause significant changes in the surface marker profile of hFCPCs, while showed some changes in the 3 lineages differentiation.

CONCLUSION

These results suggest that poly(I-C)-primed hFCPCs have an ability to modulate inflammatory response and OA phenotypes in vitro and encourage further studies to apply them in animal models of OA in the future.

Increased proliferation and differentiation capacity of placenta-derived mesenchymal stem cells from women of median maternal age correlates with telomere shortening

Mesenchymal stem cells (MSCs) experience functional decline with systemic aging, resulting in reduced proliferation, increased senescence, and lower differentiation potential. The placenta represents a valuable source of MSCs, but the possible effect of donor age on the properties of placenta-derived mesenchymal stem cells (PDMSCs) has not been thoroughly studied. Thus, the aim of this study was to underscore the effect of maternal age on the biological characteristics and stemness properties of PDMSCs. PDMSCs were isolated from 5 donor age groups (A: 18-21, B: 22-25, C: 26-30, D:31-35 and E: ≥36 years) for comparison of morphological, proliferative and differentiation properties. The pluripotency markers NANOG, OCT4, and SSEA4, as well as multipotency and differentiation markers, showed higher expression in PDMSCs from mothers aged 22-35 years, with up to a 7-fold increase in adipogenesis. Cumulative population doubling, cell growth curves, and colony-forming unit-fibroblast assays revealed higher self-renewal ability in donors 26-30 years old. An increase in the proliferative characteristics of PDMSCs correlated with increased telomere shortening, suggesting that shorter telomere lengths could be related to cellular division rather than aging. A clear understanding of the effect of maternal age on MSC regenerative potential will assist in increasing the effectiveness of future cell therapies.

Methionine affects the expression of pluripotency genes and protein levels associated with methionine metabolism in adult, fetal, and cancer stem cells

Intracellular and extracellular regulatory factors promote the potency and self-renewal property of stem cells. Methionine is fundamental for protein synthesis and regulation of methylation reactions. Specifically, methionine metabolism in embryonic and fetal development processes regulates gene expression profile/epigenetic identity of stem cells to achieve pluripotency and cellular functions. We aimed to reveal the differences in methionine metabolism of bone marrow (BM)-mesenchymal stem cells (MSCs), umbilical cord blood (UCB)-MSCs, and cancer stem cells (CSCs), which reflect different metabolic profiles and developmental stages of stem cells. UCB-MSC, BM-MSCs, and breast CSCs were treated with different doses (0, 10, 25, 50, and 100 µM) of l-methionine. Cell surface marker and cell cycle assessment were performed by flow cytometry. Changes in gene expressions (OCT3/4, NANOG, DMNT1, DNMT3A, and DNMT3B, MAT2A, and MAT2B) with methionine supplementation were examined by quantitative real-time polymerase chain reaction and the changes in histone methylation (H3K4me3, H3K27me3) levels were demonstrated by western blot analysis. S-adenosylmethionine//S-adenosylhomocysteine (SAM/SAH) levels were evaluated by enzyme-linked immunosorbent assay. Cells that were exposed to different concentrations of l-methionine, were mostly arrested in the G0/G1 phase for each stem cell group. It was evaluated that BM-MSCs increased all gene expressions in the culture medium-containing 100 µM methionine, in addition to SAM/SAH levels. On the other hand, UCB-MSCs were found to increase OCT3/4, NANOG, and DNMT1 gene expressions and decrease MAT2A and MAT2B expressions in the culture medium containing 10 µM methionine. Moreover, an increase was observed in the He3K4me3 methylation profile. In addition, OCT3/4, NANOG, DNMT1, and MAT2B gene expressions in CSCs increased starting from the addition of 25 µM methionine. An increase was determined in H3K4me3 protein expression at 50 and 100 µM methionine-supplemented culture condition. This study demonstrates that methionine plays a critical role in metabolism and epigenetic regulation in different stem cell groups.

Biological Characteristics and Optical Reflectance Spectroscopy of Human Placenta Derived Mesenchymal Stem Cells for Application in Regenerative Medicine

Introduction: The efficiency of stem cell isolation, culture, and biological characterization techniques for treatment is facing serious challenges. The purpose of this study was to provide a protocol for isolation and culture of three types of mesenchymal stem cells (MSCs) derived from the human placenta, amniotic membrane, and umbilical cord with high efficiency used for cell therapy. Methods: During this experimental laboratory study, 10 complete placenta samples were prepared from cesarean section mothers. The protocol for isolation and culture of mesenchymal cells from the placenta tissue, umbilical cord, and amniotic membrane was enzymatically optimized. The morphological features of mesenchymal cells were investigated using an inverted microscope and their biological features were measured using flow cytometry. The differentiation potential of the cells was evaluated by measuring their differentiation capacity into osteocytes and adipocytes. The absorption and reflectance features of the cells were recorded by optical spectroscopy. Finally, the data were statistically analyzed. Results: The expression of CD44, CD73, CD90 and CD29 markers in human placenta tissue-derived cells was significant. CD14, CD34 and CD45 markers were not expressed or were slightly expressed. These cells were highly viable and successfully differentiated into osteocytes and adipocytes. MSCs absorbed more light than visible light by showing light absorption peaks at wavelengths of about 435 and 550 nm. Conclusion: The protocol used in this study for isolation and culture of human placenta tissue-derived MSCs had significant efficiency for the production of MSCs for use in cell therapy and tissue engineering.

Management of submacular massive haemorrhage in age-related macular degeneration: comparison between subretinal transplant of human amniotic membrane and subretinal injection of tissue plasminogen activator

PURPOSE

Macular neovascularization (MNV) can complicate age-related macular degeneration (AMD) and lead to severe visual acuity reduction. Massive submacular haemorrhage (SMH) is a sight-threatening complication of MNV and a challenge in the management of complications related to MNV in AMD since the effects of anti-vascular endothelial growth factor treatment alone are insufficient. Here, we evaluate the different postoperative outcomes of patients affected by MNV complicated by SMH that underwent subretinal implant of human amniotic membrane (hAM) or subretinal injection of tissue plasminogen activator (tPA).

METHODS

This is a retrospective, consecutive, comparative, non-randomized interventional study. We included 44 eyes of 44 patients affected by AMD complicated by MNV and SMH. Twenty-two eyes underwent a pars plana vitrectomy (PPV), SMH and neovascular membrane removal, with a subretinal implant of hAM and silicone oil, and 22 eyes underwent PPV, subretinal injection of tPA, and 20% sulphur hexafluoride. The primary study outcome was visual acuity improvement. Secondary outcomes were postoperative complications, and MNV recurrence and optical coherence tomography (OCT)-Angiography parameters correlated with best-corrected visual acuity (BCVA).

RESULTS

Mean preoperative BCVA was 1.9 logarithm of the minimal angle of resolution (logMAR) in the amniotic membrane-group and 2 logMAR in the tPA-group. The mean final BCVA values were 1.25 and 1.4 logMAR, respectively, with a statistically significant difference. Optical coherence tomography (OCT)-Angiography scan was be used to evaluate the retinal vascularization in the treated eye.

CONCLUSION

Both techniques report similar VA improvements and postoperative complications. However, transplantation of hAM seems to have a significant benefit in inhibiting MNV recurrence.

Cell therapy for factor V deficiency: An approach based on human decidua mesenchymal stem cells

Deficiency of factor V is a congenital autosomal recessive coagulopathy associated with mutations in the F5 gene that results in mild-to-severe bleeding episodes. Factor V is a component of the prothrombinase complex responsible for accelerating conversion of prothrombin to thrombin. At the present time there are no therapeutic factor V concentrates available. This study was designed to lay the preliminary foundations for future cell-based therapy for patients with severe factor V deficiency. The study showed that hepatospheres, which produce coagulation factors VIII, IX, and V, synthetize and store intracellular glycogen and express albumin levels up to 8 times higher than those of undifferentiated cells. Factor IX and factor V gene expression increased significantly in hepatospheres as compared to undifferentiated cells, whereas factor VIII gene expression remained constant. The factor V protein was detected in the hepatospheres´ secretome. Considering the enormous potential of mesenchymal stem cells as therapeutic agents, this study proposes a highly reproducible method to induce differentiation of mesenchymal stem cells from human placenta to factor V-producing hepatospheres. This strategy constitutes a preliminary step towards a curative treatment of factor V deficiency through advanced therapies such as cell therapy.

Stem cell therapy in liver regeneration: Focus on mesenchymal stem cells and induced pluripotent stem cells

The liver has the ability to repair itself after injury; however, a variety of pathological changes in the liver can affect its ability to regenerate, and this could lead to liver failure. Mesenchymal stem cells (MSCs) are considered a good source of cells for regenerative medicine, as they regulate liver regeneration through different mechanisms, and their efficacy has been demonstrated by many animal experiments and clinical studies. Induced pluripotent stem cells, another good source of MSCs, have also made great progress in the establishment of organoids, such as liver disease models, and in drug screening. Owing to the recent developments in MSCs and induced pluripotent stem cells, combined with emerging technologies including graphene, nano-biomaterials, and gene editing, precision medicine and individualized clinical treatment may be realized in the near future.

Stem cell therapy as a recent advanced approach in male infertility

Infertility is one of the most common problems in the world that has negative effects on society and infertile people. Among the various causes of infertility, male infertility accounts for almost half of all infertility cases. Despite advances in medicine, current male infertility treatments such as assisted reproductive technology (ART) have not been successful in treating all types of male infertility. Recently, stem cells have been considered as therapeutic targets for many diseases, including infertility, due to their self-renewing and high differentiation. The purpose of this review is to discuss different types of male infertility and the effect of various stem cells against the treatment of male infertility.

Recent trends in stem cell-based therapies and applications of artificial intelligence in regenerative medicine

Stem cells are undifferentiated cells that can self-renew and differentiate into diverse types of mature and functional cells while maintaining their original identity. This profound potential of stem cells has been thoroughly investigated for its significance in regenerative medicine and has laid the foundation for cell-based therapies. Regenerative medicine is rapidly progressing in healthcare with the prospect of repair and restoration of specific organs or tissue injuries or chronic disease conditions where the body’s regenerative process is not sufficient to heal. In this review, the recent advances in stem cell-based therapies in regenerative medicine are discussed, emphasizing mesenchymal stem cell-based therapies as these cells have been extensively studied for clinical use. Recent applications of artificial intelligence algorithms in stem cell-based therapies, their limitation, and future prospects are highlighted.

Biological characteristics and metabolic profile of canine mesenchymal stem cells isolated from adipose tissue and umbilical cord matrix

Despite the increasing demand of cellular therapies for dogs, little is known on the differences between adult and fetal adnexa canine mesenchymal stem cells (MSCs), and data on their metabolic features are lacking. The present study aimed at comparing the characteristics of canine adipose tissue (AT) and umbilical cord matrix (UC) MSCs. Moreover, for the first time in the dog, the cellular bioenergetics were investigated by evaluating the two main metabolic pathways (oxidative phosphorylation and glycolysis) of ATP production. Frozen-thawed samples were used for this study. No differences in mean cell proliferation were found (P>0.05). However, while AT-MSCs showed a progressive increase in doubling time over passages, UC-MSCs showed an initial post freezing-thawing latency. No differences in migration, spheroid formation ability, and differentiation potential were found (P>0.05). RT-PCR analysis confirmed the expression of CD90 and CD44, the lack of CD14 and weak expression of CD34, mostly by AT-MSCs. DLA-DRA1 and DLA-DQA1 were weakly expressed only at passage 0 by UC-MSCs, while they were expressed at different passages for AT-MSCs. There was no difference (P>0.05) in total ATP production between cell cultures, but the ratio between the “mitochondrial ATP Production Rate” and the “glycolytic ATP Production Rate” was higher (P<0.05) in AT- than in UC-MSCs. However, in both MSCs types the mitochondrial respiration was the main pathway of ATP production. Mitochondrial respiration and ATP turnover in UC-MSCs were higher (P<0.05) than in AT-MSCs, but both had a 100% coupling efficiency. These features and the possibility of increasing the oxygen consumption by a spare respiratory capacity of four (AT-MSCSs) and two (UC-MSCs) order of magnitude greater than basal respiration, can be taken as indicative of the cell propensity to differentiate. The findings may efficiently contribute to select the most appropriate MSCs, culture and experimental conditions for transplantation experiments in mesenchymal stem cell therapy for companion animals.

From Embryo to Adult: One Carbon Metabolism in Stem Cells

Stem cells are undifferentiated cells with self-renewal property and varying differentiation potential that allow the regeneration of tissue cells of an organism throughout adult life beginning from embryonic development. Through the asymmetric cell divisions, each stem cell replicates itself and produces an offspring identical with the mother cell, and a daughter cell that possesses the characteristics of a progenitor cell and commits to a specific lineage to differentiate into tissue cells to maintain homeostasis. To maintain a pool of stem cells to ensure tissue regeneration and homeostasis, it is important to regulate the metabolic functioning of stem cells, progenitor cells and adult tissue stem cells that will meet their internal and external needs. Upon fertilization, the zygote transforms metabolic reprogramming while implantation, embryonic development, organogenesis processes and after birth through adult life. Metabolism in stem cells is a concept that is relatively new to be enlightened. There are no adequate and comprehensive in vitro studies on the comparative analysis of the effects of one-carbon (1-C) metabolism on fetal and adult stem cells compared to embryonic and cancer stem cells' studies that have been reported recently. Since 1-C metabolism is linking parental environmental/ dietary factors and fetal development, investigating the epigenetic, genetic, metabolic and developmental effects on adult period is necessary. Several mutations and abnormalities in 1-C metabolism have been noted in disease changing from diabetes, cancer, pregnancy-related outcomes such as pre-eclampsia, spontaneous abortion, placental abruption, premature delivery, and cardiovascular diseases. In this review, the effects of 1-C metabolism, mainly the methionine and folate metabolism, in stem cells that exist in different developmental stages will be discussed.

Post-calving umbilical cord tissue offcut: A potential source for the isolation of bovine mesenchymal stem cells

Background and Aim:

Veterinary health care is an emergent area in animal sciences and innovative therapeutic approaches happen to be imperative in the present days. In view of the importance of cattle health and production, it is necessary to take up contemporary approach of stem cell therapy in this sector also. This study aimed to standardize an explant culture method of bovine umbilical tissue offcut to isolate mesenchymal stem cells (MSCs) because considerable efforts are required for ensuring easy accessibility and availability of MSCs in bulk quantity, as well as in establishing and characterizing the cell lines.

Materials and Methods:

The umbilical cord (UC) tissue matrix offcut was collected after calving. A simplified in vitro cell isolation technique was followed to collect the emerged out cells from the explants of UC. Further, we expanded these isolated cells in vitro, observed its growth kinetics, and characterized to confirm as per the criterion of bovine MSCs.

Results:

A considerable exponential growth rate of the UC-derived cells was noticed. In addition to their confirmation as MSCs, the cells also exhibited plastic adherent property and maintained the spindle-shaped morphology throughout the in vitro culture. The cultured cells were found positive MSC-specific surface markers CD105, CD90, and CD73 and were negative for hematopoietic cell marker CD45. Cytochemical studies revealed the ability of the cells to differentiate into osteogenic, chondrogenic, and adipogenic lineages.

Conclusion:

This simplified method of isolation and culture of bovine multipotent MSCs from the UC offcut collected after calving could be extrapolated for the greater availability of the cells for prospective therapeutic applications.

Insights on the Human Amniotic Membrane in Clinical Practice with a Focus on the New Applications in Retinal Surgery

Recently, the use of the human amniotic membrane (hAM) has been extended to treat retinal disorders such as refractory macular holes, retinal breaks and dry and wet age-related macular degeneration. Not only the hAM has proved to be an excellent tool for repairing retinal tissue, but it has also shown a promising regeneration potential. This review aims to highlight the novel use of the hAM in treating retinal diseases. Although the hAM has been used in the ocular anterior segment reconstruction for more than 60 years, in the last 2 years, we have found in literature articles showing the use of the hAM in the retinal surgery field with interesting results in terms of tissue healing and photoreceptor regeneration.

Applications of the Amniotic Membrane in Vitreoretinal Surgery

Recently, the use of the human amniotic membrane (hAM) has been extended to treat retinal disorders, such as macular holes that failed to close and retinal tears. The hAM has demonstrated the induction of a recovery process of the external retinal layers involving the external limiting membrane (ELM) and the ellipsoid zone (EZ). After that, the application of the hAM for retinal pathologies was extended to large macular tears, high myopic retinal detachment associated with MH, paravascular tears, serous macular detachment associated with optic pit, complicated retinal detachment and advanced age-related macular degeneration (AMD). The hAM has shown a potential in repairing retinal tissue through a regeneration process. This review aims to highlight the use of the hAM in various vitreo-retinal surgical fields, and to confront it with other cutting-edge surgical techniques used to treat challenging vitreo-retinal pathologies.

Perspective of placenta derived mesenchymal stem cells in acute liver failure

Acute Liver failure (ALF) is a life-threatening disease and is determined by coagulopathy (with INR ≥ 1.5) and hepatic encephalopathy as a result of severe liver injury in patients without preexisting liver disease. Since there are problems with liver transplantation including lack of donors, use of immunosuppressive drugs, and high costs of this process, new therapeutic approaches alongside current treatments are needed. The placenta is a tissue that is normally discarded after childbirth. On the other hand, human placenta is a rich source of mesenchymal stem cells (MSCs), which is easily available, without moral problems, and its derived cells are less affected by age and environmental factors. Therefore, placenta-derived mesenchymal stem cells (PD-MSCs) can be considered as an allogeneic source for liver disease. Considering the studies on MSCs and their effects on various diseases, it can be stated that MSCs are among the most important agents to be used for novel future therapies of liver diseases. In this paper, we will investigate the effects of mesenchymal stem cells through migration and immigration to the site of injury, cell-to-cell contact, immunomodulatory effects, and secretory factors in ALF.

Human Amniotic Membrane Plug to Restore Age-Related Macular Degeneration Photoreceptor Damage

PURPOSE

Age-related macular degeneration (AMD) is the leading cause of legal blindness in adults 65 years of age and older. Choroidal neovascularization (CNV) can complicate AMD and lead to severe visual acuity reduction. Despite the several treatments available, if the retinal pigment epithelium is damaged, we have to cope with the impossibility of restoring acceptable visual acuity using only medical treatments.

DESIGN

Prospective, consecutive, interventional study.

PARTICIPANTS

Eleven patients affected by AMD, 6 patients affected by CNV, and 5 patients affected by geographic atrophy.

METHODS

All patients underwent a pars plana vitrectomy with subretinal implantation of human amniotic membrane (hAM) to induce photoreceptor regeneration and partial visual acuity restoration.

MAIN OUTCOME MEASURES

Primary study outcome was visual acuity improvement. Secondary outcomes were multimodal imaging results.

RESULTS

Mean preoperative best-corrected visual acuity (BCVA) was 20/2000 (2 logarithm of the minimum angle of resolution [logMAR]), and all the patients showed a BCVA of counting fingers or less. Mean final BCVA was 20/400 (1.31 logMAR), ranging from 20/2000 to 20/100 (2-0.7 logMAR). OCT angiography was used to measure retinal vascularization in the treated eye compared with the fellow eye. A high correlation between BCVA and deep vascular density was evidenced. Adaptive optics findings, obtained over the retinal area where the highest functionality was observed, were evaluated using microperimetry. The images showed possible photoreceptor presence over the hAM membrane.

CONCLUSIONS

This work supports the feasibility and safety of the hAM to promote partial retinal function restoration 6 months after surgery with visual acuity improvement. The advanced diagnostics help to understand the interaction between the hAM and photoreceptors and suggest that photoreceptor regeneration may occur.

Use of Human Placenta-Derived Cells in a Preclinical Model of Tendon Injury

BACKGROUND

Emerging data suggest that human cells derived from extraembryonic tissues may have favorable musculoskeletal repair properties. The purpose of this study was to determine whether the injection of human placenta-derived mesenchymal-like stromal cells, termed placental expanded cells (PLX-PAD), would improve tendon healing in a preclinical model of tendinopathy.

METHODS

Sixty male Sprague-Dawley rats underwent bilateral patellar tendon injection with either saline solution (control) or PLX-PAD cells (2 × 10 cells/100 µL) 6 days after collagenase injection to induce tendon degeneration. Animals were killed at specific time points for biomechanical, histological, and gene expression analyses of the healing patellar tendons.

RESULTS

Biomechanical testing 2 weeks after the collagenase injury demonstrated better biomechanical properties in the tendons treated with PLX-PAD cells. The load to failure of the PLX-PAD-treated tendons was higher than that of the saline-solution-treated controls at 2 weeks (77.01 ± 10.51 versus 58.87 ± 11.97 N, p = 0.01). There was no significant difference between the 2 groups at 4 weeks. There were no differences in stiffness at either time point. Semiquantitative histological analysis demonstrated no significant differences in collagen organization or cellularity between the PLX-PAD and saline-solution-treated tendons. Gene expression analysis demonstrated higher levels of interleukin-1β (IL-1β) and IL-6 early in the healing process in the PLX-PAD-treated tendons.

CONCLUSIONS

Human placenta-derived cell therapy induced an early inflammatory response and a transient beneficial effect on tendon failure load in a model of collagenase-induced tendon degeneration.

CLINICAL RELEVANCE

Human extraembryonic tissues, such as the placenta, are an emerging source of cells for musculoskeletal repair and may hold promise as a point-of-care cell therapy for tendon injuries.

The Use and Delivery of Stem Cells in Nerve Regeneration: Preclinical Evidence and Regulatory Considerations

Outcomes following peripheral nerve injury remain poor despite the regenerative capacity displayed by the peripheral nervous system. Current therapies are limited and do not provide satisfactory functional recovery in a multitude of cases. Biomaterials have decreased the need for nerve autograft across small nerve gaps in small-caliber nerves, but the lack of a cellular substrate presents a limiting factor to the effectiveness of this therapy. Schwann cells are the supportive cells in the peripheral nervous system and play an integral role in the physiological response and regeneration following nerve injury. Limitations to autologous Schwann cells include donor site morbidity during harvesting, limited expansion capability, and finite source. Stem cells are multipotent or pluripotent cells with self-renewing capabilities that show promise to improve functional recovery following nerve injury. Differentiation of stem cells into supportive Schwann cells could provide additional trophic support without the disadvantages of autologous Schwann cells, providing an avenue to improve existing therapies. A variety of stem cells have been evaluated in animal models for this clinical application; the current options, along with their clinical feasibility, are summarized in this article.

Comparison efficacy of ESWT and Wharton's jelly mesenchymal stem cell in early osteoarthritis of rat knee

Application of extracorporeal shockwave therapy (ESWT) to the subchondral bone of medial tibia condyle has shown chondroprotective effects of the knee with decreased cartilage degradation and improved subchondral bone remodeling in the osteoarthritis (OA) of rat knee. Recently, transplantation of ex vivo preparations of mesenchymal stem cells (MSCs) to animal or human joints with OA seems to induce therapeutically effective repair because of paracrine responses from host cells including progenitor cells residing within the synovium. This study compared ESWT, Wharton's jelly mesenchymal stem cells (WJMSCs) and combination of ESWT and WJMSCs therapies for early OA of the rat knee. The results showed ESWT, WJMSCs and combination of therapies significantly improved early OA knee based on analysis of pathological findings, micro-CT and immunohistochemistry (IHC) stain. The combined therapy group increased the bone volume (61.755 ± 1.537), and trabecular thickness (0.215 ± 0.014; P < 0.01) as well as reduced synovitis (1.8 ± 0.37) more than ESWT or WJMSCs individually. However, there were no significant difference in combined ESWT and WJMSCS as shown in the expressions of IGF-1 and TGF-β1 and reduction of the TUNEL activity on OA knee. Furthermore, WJMSCs treatment significantly increased the expression of the type II collagen (22.62 ± 0.84; P < 0.001) when compared with ESWT (6.97 ± 0.54) and ESWT combined with WJMSCs (8.87 ± 0.31) in OA knee. In mechanistic factors analysis, the synergistic effect was observed by ESWT combined with WJMSCs in the expression of RUNX-2, SOX-9 and Collagen Xα1 on OA knee. Our results provided the innovative information of ESWT, and WJMSCs in the treatment of early osteoarthritis of the knee in rats.

Human Trophoblast Progenitor Cells Express and Release Angiogenic Factors

Trophoblast stem cells develop from polar trophectoderm and give rise to the cells that generate the placenta. Trophoblast cells are responsible for the uterine invasion and vascular remodeling during the implantation of the embryo. However this knowledge is not yet to be confirmed for trophoblast progenitor cells (TPCs). In this study, we aimed to demonstrate that human TPCs (hTPCs) express and release angiogenic factors for the first time. TPCs were isolated from the term placenta. Then immunophenotyping was performed by FACS method by analyzing caudal type homeobox 2 (CDX2) and eomesodermin (EOMES). Immunofluorescence staining of CDX2 and EOMES was performed on these cells. Lastly, angiogenesis-related proteins were detected by western blot and ELISA assays. The isolated cells were positive for trophoblast stem cell markers CDX2 and EOMES in 92.5% and 92.7% of cells, respectively showing the characteristics of TPCs. The investigation of vascular endothelial growth factor (VEGF), vascular endothelial growth factor receptor 1 (VEGFR1), and vascular endothelial growth factor receptor 2 (VEGFR2) at protein and mRNA level in comparison with human umbilical vein endothelial cells (HUVECs), revealed that human TPCs (hTPCs) have higher levels of VEGF and VEGFR1 transcripts. Additionally soluble forms of VEGF and VEGFR1 were detected in supernatants of hTPCs. With this information, TPCs seem to be promising for regenerative cell therapies by increasing angiogenesis.

Renogenic characterization and in vitro differentiation of rat amniotic fluid stem cells into renal proximal tubular- and juxtaglomerular-like cells

The aim of the present study was to investigate the renogenic characteristics of amniotic fluid stem cells (AFSCs) and to evaluate their in vitro differentiation potential into renal proximal tubular-like cells and juxtaglomerular-like cells. We culture expanded AFSCs derived from rat amniotic fluid. The AFSCs grew as adherent spindle-shaped cells and expressed mesenchymal markers CD73, CD90, and CD105 as well as renal progenitor markers WT1, PAX2, SIX2, SALL1, and CITED1. AFSCs exhibited an in vitro differentiation potential into renal proximal tubular epithelial-like cells, as shown by the upregulation of expression of proximal tubular cell-specific genes like AQP1, CD13, PEPT1, GLUT5, OAT1, and OCT1. AFSCs could also be differentiated into juxtaglomerular-like cells as demonstrated by the expression of renin and α-SMA. The AFSCs also expressed pluripotency markers OCT4, NANOG, and SOX2 and could be induced into embryoid bodies with differentiation into all the three germ layers, highlighting the pluripotent nature of these cells. Our results show that amniotic fluid contains a population of primitive stem cells that express renal-progenitor markers and also possess the propensity to differentiate into two renal lineage cell types and, thus, may have a therapeutic potential in renal regenerative medicine.

Therapeutic abortion and ectopic pregnancy: alternative sources for fetal stem cell research and therapy in Iran as an Islamic country

Regenerative medicine as a background of stem cell research and therapy has a long history. A wide variety of diseases including Parkinson's disease, heart diseases, multiple sclerosis, spinal cord injury, diabetes mellitus and etc. are candidate to be treated using different types of stem cells. There are several sources of stem cells such as bone marrow, umbilical cord, peripheral blood, germ cells and the embryo/fetus tissues. Fetal stem cells (FSCs) and embryonic stem cells (ESCs) have been described as the most potent stem cell source. Although their pluri- or multipotent properties leads to promising reports for their clinical applications, owning to some ethical and legal obstacles in different communities such as Muslim countries, care should be taken for therapeutic applications of FSCs and ESCs. Derivation of these cell types needs termination of pregnancy and embryo or fetus life that is prohibited according to almost all rules and teaches in Muslim communities. Abortion and termination of pregnancy under a normal condition for the procurement of stem cell materials is forbidden by nearly all the major world religions such as Islam. Legislated laws in the most of Muslim countries permit termination of pregnancy and abortion only when the life of the mother is severely threatened or when continuing pregnancy may lead to the birth of a mentally retarded, genetically or anatomically malformed child. Based on the rules and conditions in Islamic countries, finding an alternative and biologically normal source for embryonic or fetal stem cell isolation will be too difficult. On the one hand, Muslim scientists have the feasibility for finding of genetically and anatomically normal embryonic or fetal stem cell sources for research or therapy, but on the other hand they should adhere to the law and related regional and local rules in all parts of their investigation. The authors suggest that the utilization of ectopic pregnancy (EP) conceptus, extra-embryonic tissues, and therapeutic abortion materials as a valuable source of stem cells for research and medical purposes can overcome limitations associated with finding the appropriate stem cell source. Pregnancy termination because of the mentioned subjects is accepted by almost all Islamic laws because of maternal lifesaving. Also, there are no ethical or legal obstacles in the use of extra-embryonic or EP derived tissues which lead to candidate FSCs as a valuable source for stem cell researches and therapeutic applications.

Electrospun Nanofibrous Meshes Cultured With Wharton's Jelly Stem Cell: An Alternative for Cartilage Regeneration, Without the Need of Growth Factors

Many efforts are being directed worldwide to the treatment of OA-focal lesions. The majority of those efforts comprise either the refinement of surgical techniques or combinations of biomaterials with various autologous cells. Herein, we tested electrospun polycaprolactone (PCL) nanofibrous meshes for cartilage tissue engineering. For that, articular chondrocytes (hACs) isolated from human osteoarthritic joints and Wharton's Jelly Stem Cells (hWJSCs) are cultured on electrospun nanofiber meshes, without adding external growth factors. We observed higher glycosaminoglycans production and higher over-expression of cartilage-related genes from hWJSCs cultured with basal medium, when compared to hACs isolated from osteoarthritic joints. Moreover, the presence of sulfated proteoglycans and collagen type II is observed on both types of cell cultures. We believe that this effect is due to either the electrospun nanofibers topography or the intrinsic chondrogenic differentiation potential of hWJSCs. Therefore, we propose the electrospun nanofibrous scaffolds in combination with hWJSCs as a viable alternative to the commercial membranes used in autologous chondrogenic regeneration approaches.

Cell-based approaches for augmentation of tendon repair

Cell-based approaches are among the principal interventions in orthobiologics to improve tendon and ligament healing and to combat degenerative processes. The number of options available for investigation are expanding rapidly and investigators have an increasing number of cell types to choose from for research purposes. However, in part due to the current regulatory environment, the list of available cells at clinicians' disposal for therapeutic purposes is still rather limited. In this review, we present an overview of the main cellular categories in current use. Notable recent developments in cell-based approaches include the introduction of diverse sources of mesenchymal stem cells, pluripotent cells of extra-embryonic origin, and the emerging popularity of fully differentiated cells such as tenocytes and endothelial cells. Delivery strategies are discussed and a succinct discussion of the current regulatory environment in the United States is presented.

Influence of hypoxia on the stemness of umbilical cord matrix-derived mesenchymal stem cells cultured on chitosan films

Chitosan is attractive as a substrate for stem cell expansion because it improves stemness through formation of spheroids. Hypoxia has also been proposed as a strategy to enhance stemness and survival of stem cells after in vivo implantation. This study was therefore designed to evaluate the influence of hypoxia on chitosan-induced behavior of stem cells. Umbilical cord matrix-derived stem cells were cultured on chitosan film or standard plate under normoxia and hypoxia, for 3 and 7 days. Based on immunophenotyping, chitosan strongly suppresses the expression of CD90 and CD105 cell surface markers, changes partially reversed by combined exposure to hypoxia. Hypoxia generally increased the volume and number of spheroids formed on chitosan, but the cellularity of cultures on chitosan films remained lower than that of standard plates. After 7 days of culture, the expression of stemness related genes (Oct4, Sox2, and Nanog) was best stimulated by combined exposure to chitosan and hypoxia. Based on our results, conditioning stem cells for 7 days on chitosan films under hypoxic conditions is recommended to enhance the stemness of stem cells, and minimize cell loss due to lack of attachment on chitosan. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 501-511, 2018.

Modulators of the Balance between M1 and M2 Macrophages during Pregnancy

Macrophages are a subset of mononuclear phagocytes of the innate immune system with high plasticity and heterogeneity. At the maternal–fetal interface, macrophages are present in all stages of pregnancy and involved in a variety of activities, including regulation of immune cell activities, decidualization, placental cell invasion, angiogenesis, parturition, and postpartum uterine involution. The activation state and function of uterine–placental macrophages are largely dependent on the local tissue microenvironment. However, disruption of the uterine microenvironment can have profound effects on macrophage activity and subsequently impact pregnancy outcome. Thus, appropriately and timely regulated macrophage polarization has been considered a key determinant of successful pregnancy. Targeting macrophage polarization might be an efficient strategy for maintaining maternal–fetal immune homeostasis and a normal pregnancy. Here, we will review the latest findings regarding the modulators regulating macrophage polarization in healthy pregnancies and pregnancy complications, which might provide a basis for macrophage-centered therapeutic strategies.

Phenotype and multipotency of rabbit (Oryctolagus cuniculus) amniotic stem cells

BACKGROUND

Stem cells are capable of unlimited self-renewal and are able to remain undifferentiated for extended periods of time prior to their differentiation into specific cell lineages. Because of the issues (ethical and religious) involved in the use of embryonic stem cells and the limited plasticity of adult stem cells, an alternative cell source could be foetal stem cells derived from extra-embryonic tissue, which are highly proliferative, grow in vitro and possess interesting immunogenic characteristics. As a result, the amniotic membrane of several species has been studied as an important new source of stem cells.

METHODS

Here, we cultured and characterized mesenchymal progenitor cells derived from the rabbit amniotic membrane, and investigated their differentiation potential. In total, amniotic membranes were collected from eight rabbit foetuses and were isolated by the explant technique. The obtained cells were cultured in DMEM-HIGH glucose and incubated at 37 °C in a humidified atmosphere with 5% CO2.

RESULTS

The cells adhered to the culture plates and showed a high proliferative capacity with fibroblast-like morphologies. The cells showed a positive response for markers for the cytoskeleton, mesenchymal stem cells and proliferation, pluripotency and haematopoietic precursor stem cells. However, the cells were negative for CD45, a marker of haematopoietic cells. Furthermore, the cells had the capacity to be induced to differentiate into osteogenic, adipogenic and chondrogenic lineages. In addition, when the cells were injected into nude mice, we did not observe the formation of tumours.

CONCLUSIONS

In summary, our results demonstrate that multipotent mesenchymal stem cells can be obtained from the rabbit amniotic membrane for possible use in future cell therapy applications.

Comparative study on characterization and wound healing potential of goat (Capra hircus) mesenchymal stem cells derived from fetal origin amniotic fluid and adult bone marrow

Caprine amniotic fluid (cAF) and bone marrow cells (cBM) were isolated, expanded and phenotypically characterized by mesenchymal stem cells (MSCs) specific cell surface markers. Both cell types were compared for multilineage differentiation potential by flow cytometry using specific antibodies against lineage specific markers. Furthermore, in vitro expanded cAF-MSCs showed higher expression of trophic factors viz. VEGF and TGF-β1 as compared to cBM-MSCs. Full-skin thickness excisional wounds created on either side of the dorsal midline (thoracolumbar) of New Zealand White rabbits were randomly assigned to subcutaneous injection of either fetal origin cAF-MSCs (n=4) or adult cBM-MSCs (n=4) or sterile PBS (control, n=4). The rate of wound closure was found faster (p<0.05) in cAF-MSCs treated wounds as compared with cBM-MSCs and PBS treated wounds especially on 21st day post-skin excision. Histomorphological examination of the healing tissue showed that wound healing was improved (p<0.05) by greater epithelialization, neovascularization and collagen development in cAF-MSCs as compared to cBM-MSCs and PBS treated wounds.

Regenerative efficacy of mesenchymal stromal cells from human placenta in sensorineural hearing loss

INTRODUCTION

Hearing loss is a common chronic disorder characterized by decline of auditory function. The global population have suffered from deafness and the transplantation of stem cells is regarded as a therapeutic strategy for this disease.

METHODS

We collected placenta from a total of 13 samples of full term pregnant women and isolated MSCs derived from human placenta and transplanted MSCs on deaf animal model. The normal group and the sensorineural hearing loss (SNHL) group and the experimental (transplanted MSCs) group were compared and estimated hearing level using auditory brainstem response (ABR) recordings and the otoacoustic emission (OAE) test.

RESULTS

ABR threshold value and DPOAE level showed that MSCs transplantation groups was improved than the SNHL group. And the number of spiral ganglion neurons were increased in all turn of the cochlea. And there was no evidence of acute immunological rejection and inflammation response was not observed.

DISCUSSION

This study is to evaluate regenerative efficacy of hearing loss by transplanting mesenchymal stromal cells (MSCs) derived from human placenta (amnion and chorion) in deaf animal model. We identified that MSCs transplantation restored auditory impairment and promoted cell regeneration. We hope to overcome sensorineural hearing loss by transplanting stem cells such as mesenchymal stromal cells (MSCs) from easily accessible adult stem cell source in placenta.

Primordial germ cell-like cells derived from canine adipose mesenchymal stem cells

OBJECTIVES

Previous studies have shown that adipose mesenchymal stem cells (AMSCs) share the potency of typical bone marrow mesenchymal stem cells (MSCs); however, there is little information concerning characteristics of canine AMSCs (CAMSCs); it has not previously been made clear whether CAMSCs would be able to differentiate into other cell types.

MATERIALS AND METHODS

In this study, typical AMSC lines were established, and their characteristics including morphology, typical markers and differentiation potentiality were tested.

RESULTS

The cells exhibited typical MSC morphology and were positive for CD90, CD44 and CD166, considered to be MSCs surface markers. They were negative for CD34 and CD45. The CAMSCs also exhibited embryonic stem cell (ESC) markers, including Oct4 and Sox2, at passage 2. In an appropriate microenvironment, CAMSCs differentiated into EBs and were able to produce cells of the three germ layers. These results indicate that established cells were putative adipocyte-derived MSCs, which also displayed properties of ESCs. Moreover, when the CAMSCs were induced by bone morphogenetic protein 4 (BMP4), they differentiated into PGC-like cells (PGCLCs) and male germ-like cells, which were positive for PR domain-containing 1 (Prdm1), PR domain-containing 14 (Prdm14), doublesex and mab-3 related transcription factor (Dmrt1), as well as for promyelocytic leukaemia zinc finger (Plzf). Quantitative real-time PCR (qRT-PCR) and western blotting analysis verified higher expression levels of these markers.

CONCLUSION

This study provides an efficient approach to study germ cell development using CAMSCs.

Chorionic villi derived mesenchymal like stem cells and expression of embryonic stem cells markers during long-term culturing

Mesenchymal stem cells (MSCs) can be obtained from a variety of human tissues. MSCs derived from placental chorionic villi of the first trimester are likely to resemble, biologically, embryonic stem cells (ESC), due to the earlier development stage of placenta. In the present study long-term cultures of MSC-like cells were assessed in order to evaluate MSCs multipotent characteristics and molecular features during the period of culture. CV-cells obtained from 10 samples of chorionic villus displayed typical fibroblastoid morphology, undergone 20 passages during a period of 120 days, maintaining a stable karyotype throughout long term expansion. The cells were positive, for CD90, CD73, CD105, CD29, CD44, HLA ABC antigens and negative for CD14, CD34, AC133, and HLA DR antigens as resulted from the flow cytometry analysis. CV-cells were differentiated in adipocytes, osteoblasts, chondrocytes and neuronal cells under specific culture conditions. The expression of the ESC-gene markers POU5F1 (Oct-4) and NANOG was observed at earliest stages (4-12 passages) and not at the late stages (14-20 passages) by RT-PCR analysis. ZFP42 and SOX2 expression were not detected. Moreover, CV-cells were found to express GATA4 but not NES (Nestin). Chorionic villi-derived cells possess multipotent properties, display high proliferation rate and self-renew capacity, share common surface antigens with adult MSCs and express certain embryonics stem cells gene markers. These characteristics highlight chorionic villi as an attractive source of MSCs for the needs of regenerative medicine.

The Role of HPV in Head and Neck Cancer Stem Cell Formation and Tumorigenesis

The cancer stem cell (CSC) theory proposes that a minority of tumor cells are capable of self-replication and tumorigenesis. It is these minority of cells that are responsible for cancer metastasis and recurrence in head and neck squamous cell cancers (HNSCC). Human papilloma virus (HPV)-related cancer of the oropharynx is becoming more prevalent, which makes understanding of the relationship between HPV and CSCs more important than ever. This relationship is critical because CSC behavior can be predicted based on cell surface markers, which makes them a suitable candidate for targeted therapy. New therapies are an exciting opportunity to advance past the stalled outcomes in HNSCC that have plagued patients and clinicians for several decades.

Sendai Virus-Based Reprogramming of Mesenchymal Stromal/Stem Cells from Umbilical Cord Wharton's Jelly into Induced Pluripotent Stem Cells

In an attempt to bring pluripotent stem cell biology closer to reaching its full potential, many groups have focused on improving reprogramming protocols over the past several years. The episomal modified Sendai virus-based vector has emerged as one of the most practical ones. Here we describe reprogramming of mesenchymal stromal/stem cells (MSC) derived from umbilical cord Wharton's Jelly into induced pluripotent stem cells (iPSC) using genome non-integrating Sendai virus-based vectors. The detailed protocols of iPSC colony cryopreservation (vitrification) and adaption to feeder-free culture conditions are also included.

Comparison of the Expression of Hepatic Genes by Human Wharton's Jelly Mesenchymal Stem Cells Cultured in 2D and 3D Collagen Culture Systems

BACKGROUND

Human Wharton's jelly mesenchymal stem cells (HWJMSCs) express liver-specific markers such as albumin, alpha-fetoprotein, cytokeratin-19, cytokeratin-18, and glucose-6-phosphatase. Therefore, they can be considered as a good source for cell replacement therapy for liver diseases. This study aimed to evaluate the effects of various culture systems on the hepatocyte-specific gene expression pattern of naïve HWJMSCs.

METHODS

HWJMSCs were characterized as MSCs by detecting the surface CD markers and capability to differentiate toward osteoblast and adipocyte. HWJMSCs were cultured in 2D collagen films and 3D collagen scaffolds for 21 days and were compared to control cultures. Real time RT-PCR was used to evaluate the expression of liver-specific genes.

RESULTS

The HWJMSCs which were grown on non-coated culture plates expressed cytokeratin-18 and -19, alpha-fetoprotein, albumin, glucose-6-phosphatase, and claudin. The expression of the hepatic nuclear factor 4 (HNF4) was very low. The cells showed a significant increase in caludin expression when they cultured in 3D collagen scaffolds compared to the conventional monolayer culture and 2D collagen scaffold.

CONCLUSION

Various culture systems did not influence on hepatocyte specific marker expression by HWJMSCs, except for claudin. The expression of claudin showed that 3D collagen scaffold provided the extracellular matrix for induction of the cells to interconnect with each other.

Regionally-derived cell populations and skeletal stem cells from human foetal femora exhibit specific osteochondral and multi-lineage differentiation capacity in vitro and ex vivo

Background

Adult skeletal stem cells (SSCs) often exhibit limited in vitro expansion with undesirable phenotypic changes and loss of differentiation capacity. Foetal tissues offer an alternative cell source, providing SSCs which exhibit desirable differentiation capacity over prolonged periods, ideal for extensive in vitro and ex vivo investigation of fundamental bone biology and skeletal development.

Methods

We have examined the derivation of distinct cell populations from human foetal femora. Regionally isolated populations including epiphyseal and diaphyseal cells were carefully dissected. Expression of the SSC marker Stro-1 was also found in human foetal femora over a range of developmental stages and subsequently utilised for immuno-selection.

Results

Regional populations exhibited chondrogenic (epiphyseal) and osteogenic (diaphyseal) phenotypes following in vitro and ex vivo characterisation and molecular analysis, indicative of native SSC maturation during skeletal development. However, each population exhibited potential for induced multi-lineage differentiation towards bone (bone nodule formation), cartilage (proteoglycan and mucopolysaccharide deposition) and fat (lipid deposition), suggesting the presence of a shared stem cell sub-population. This shared sub-population may be comprised of Stro-1+ cells, which were later identified and immuno-selected from whole foetal femora exhibiting multi-lineage differentiation capacity in vitro and ex vivo.

Conclusions

Distinct populations were isolated from human foetal femora expressing osteochondral differentiation capacity. Stro-1 immuno-selected SSCs were isolated from whole femora expressing desirable multi-lineage differentiation capacity over prolonged in vitro expansion, superior to their adult-derived counterparts, providing a valuable cell source with which to study bone biology and skeletal development.

Electronic supplementary material

The online version of this article (doi:10.1186/s13287-015-0247-2) contains supplementary material, which is available to authorized users.

The efficacy of extraembryonic stem cells in improving blood flow within animal models of lower limb ischaemia

BACKGROUND

Stem cell (SC) administration is a potential therapeutic strategy to improve blood supply in patients with peripheral artery disease (PAD). The aim of this systematic review and meta-analysis was to investigate the efficacy of extraembryonic tissue-derived SC (ETSC) in improving blood flow within animal models of hindlimb ischaemia (HLI).

METHODS

PubMed, ScienceDirect and Web of Science were searched to identify studies which investigated ETSCs within animal HLI models. A meta-analysis was performed focusing on the effect of ETSCs on limb blood flow assessed by laser Doppler imaging using a random effects model. Methodological quality was assessed using a newly devised quality assessment tool.

RESULTS

Five studies investigating umbilical cord-derived SCs (three studies), placental SCs (one study), amnion and chorionic SCs (one study) were included. A meta-analysis suggested that administration of ETSCs improved the restoration of blood flow within the HLI models used. The methodological quality of the included studies was assessed as poor. Problems identified included lack of randomised design and blinding of outcome assessors; that the animal models did not incorporate recognised risk factors for human PAD or atherosclerosis; the models used did not have established chronic ischaemia as is the cases in most patients presenting with PAD; and the studies lacked a clear rationale for the dosage and frequency of SCs administered.

CONCLUSIONS

The identified studies suggest that ETSCs improve recovery of limb blood supply within current animal HLI models. Improved study quality is, however, needed to provide support for the likelihood of translating these findings to patients with PAD.

Amniotic mesenchymal cells from pre-eclamptic placentae maintain immunomodulatory features as healthy controls

Pre‐eclampsia (PE) is one of the most severe syndromes in human pregnancy, and the underlying mechanisms of PE have yet to be determined. Pre‐eclampsia is characterized by the alteration of the immune system's activation status, an increase in inflammatory Th1/Th17/APC cells, and a decrease in Th2/Treg subsets/cytokines. Moreover, inflammatory infiltrates have been detected in the amniotic membranes of pre‐eclamptic placentae, and to this date limited data are available regarding the role of amniotic membrane cells in PE. Interestingly, we and others have previously shown that human amniotic mesenchymal stromal cells (hAMSC) possess anti‐inflammatory properties towards almost all immune cells described to be altered in PE. In this study we investigated whether the immunomodulatory properties of hAMSC were altered in PE. We performed a comprehensive study of cell phenotype and investigated the in vitro immunomodulatory properties of hAMSC isolated from pre‐eclamptic pregnancies (PE‐hAMSC), comparing them to hAMSC from normal pregnancies (N‐hAMSC). We demonstrate that PE‐hAMSC inhibit CD4/CD8 T‐cell proliferation, suppress Th1/Th2/Th17 polarization, induce Treg and block dendritic cells and M1 differentiation switching them to M2 cells. Notably, PE‐hAMSC generated a more prominent induction of Treg and higher suppression of interferon‐γ when compared to N‐hAMSC, and this was associated with higher transforming growth factor‐β1 secretion and PD‐L2/PD‐L1 expression in PE‐hAMSC. In conclusion, for the first time we demonstrate that there is no intrinsic impairment of the immunomodulatory features of PE‐hAMSC. Our results suggest that amniotic mesenchymal stromal cells do not contribute to the disease, but conversely, could participate in offsetting the inflammatory environment which characterizes PE.

Chorion Mesenchymal Stem Cells Show Superior Differentiation, Immunosuppressive, and Angiogenic Potentials in Comparison With Haploidentical Maternal Placental Cells

Mesenchymal stem cells (MSCs) of placental origin have become increasingly translational owing to their abundance and accessibility. MSCs of different origin share several features but also present biological differences that might point to distinct clinical properties. Hence, mixing fetal and maternal cells from the same placenta can lead to contradicting results. We analyzed the biological characteristics of haploidentical MSCs isolated from fetal sources, including the umbilical cord (UC-MSCs) and chorion (Ch-MSCs), compared with maternal decidua MSCs (Dc-MSCs). All MSCs were analyzed for general stem cell properties. In addition, immunosuppressive capacity was assessed by the inhibition of T-cell proliferation, and angiogenic potential was evaluated in a Matrigel transplantation assay. The comparison between haploidentical MSCs displayed several distinct features, including (a) marked differences in the expression of CD56, (b) a higher proliferative capacity for Dc-MSCs and UC-MSCs than for Ch-MSCs, (c) a diversity of mesodermal differentiation potential in favor of fetal MSCs, (d) a higher capacity for Ch-MSCs to inhibit T-cell proliferation, and (e) superior angiogenic potential of Ch-MSCs evidenced by a higher capability to form tubular vessel-like structures and an enhanced release of hepatocyte growth factor and vascular endothelial growth factor under hypoxic conditions. Our results suggest that assessing the prevalence of fetomaternal contamination within placental MSCs is necessary to increase robustness and limit side effects in their clinical use. Finally, our work presents evidence positioning fetoplacental cells and notably Ch-MSCs in the forefront of the quest for cell types that are superior for applications in regenerative medicine.

SIGNIFICANCE

This study analyzed the biological characteristics of mesenchymal stem cells (MSCs) isolated from fetal and maternal placental origins. The findings can be summarized as follows: (a) important differences were found in the expression of CD56, (b) a different mesodermal differentiation potential was found in favor of fetal MSCs, (c) a higher immunosuppressive capacity for chorion MSCs was noted, and (d) superior angiogenic potential of Ch-MSCs was observed. These results suggest that assessing the prevalence of fetomaternal contamination within placental MSCs is necessary to increase robustness and limit side effects in their clinical use. The evidence should allow clinicians to view fetoplacental cells, notably Ch-MSCs, favorably as candidates for use in regenerative medicine.

In vitro chondrogenic commitment of human Wharton's jelly stem cells by co-culture with human articular chondrocytes

Wharton's jelly stem cells (WJSCs) are a potential source of transplantable stem cells in cartilage-regenerative strategies, due to their highly proliferative and multilineage differentiation capacity. We hypothesized that a non-direct co-culture system with human articular chondrocytes (hACs) could enhance the potential chondrogenic phenotype of hWJSCs during the expansion phase compared to those expanded in monoculture conditions. Primary hWJSCs were cultured in the bottom of a multiwell plate separated by a porous transwell membrane insert seeded with hACs. No statistically significant differences in hWJSCs duplication number were observed under either of the culture conditions during the expansion phase. hWJSCs under co-culture conditions show upregulations of collagen type I and II, COMP, TGFβ1 and aggrecan, as well as of the main cartilage transcription factor, SOX9, when compared to those cultured in the absence of chondrocytes. Chondrogenic differentiation of hWJSCs, previously expanded in co-culture and monoculture conditions, was evaluated for each cellular passage using the micromass culture model. Cells expanded in co-culture showed higher accumulation of glycosaminoglycans (GAGs) compared to cells in monoculture, and immunohistochemistry for localization of collagen type I revealed a strong detection signal when hWJSCs were expanded under monoculture conditions. In contrast, type II collagen was detected when cells were expanded under co-culture conditions, where numerous round-shaped cell clusters were observed. Using a micromass differentiation model, hWJSCs, previously exposed to soluble factors secreted by hACs, were able to express higher levels of chondrogenic genes with deposition of cartilage extracellular matrix components, suggesting their use as an alternative cell source for treating degenerated cartilage. Copyright © 2015 John Wiley & Sons, Ltd.