Umbilical Cord Tissue Offers the Greatest Number of Harvestable Mesenchymal Stem Cells for Research and Clinical Application: A Literature Review of Different Harvest Sites

Cell-based therapies have disease-modifying effects on osteoarthritis in animal models: A systematic review by the ESSKA Orthobiologic Initiative. Part 3: Umbilical cord, placenta, and other sources for cell-based injectable therapies

PURPOSE

This systematic review aimed to investigate in animal models the presence of disease-modifying effects driven by non-bone marrow-derived and non-adipose-derived products, with a particular focus on umbilical cord and placenta-derived cell-based therapies for the intra-articular injective treatment of osteoarthritis (OA).

METHODS

A systematic review was performed on three electronic databases (PubMed, Web of Science and Embase) according to PRISMA guidelines. The results were synthesised to investigate disease-modifying effects in preclinical animal studies comparing injectable umbilical cord, placenta, and other sources-derived products with OA controls. The risk of bias was assessed using the SYRCLE tool.

RESULTS

A total of 80 studies were included (2314 animals). Cell therapies were most commonly obtained from the umbilical cord in 33 studies and placenta/amniotic tissue in 18. Cell products were xenogeneic in 61 studies and allogeneic in the remaining 19 studies. Overall, 25/27 (92.6%) of studies on umbilical cord-derived products documented better results compared to OA controls in at least one of the following outcomes: macroscopic, histological and/or immunohistochemical findings, with 19/22 of studies (83.4%) show positive results at the cartilage level and 4/6 of studies (66.7%) at the synovial level. Placenta-derived injectable products documented positive results in 13/16 (81.3%) of the studies, 12/15 (80.0%) at the cartilage level, and 2/4 (50.0%) at the synovial level, but 2/16 studies (12.5%) found overall worse results than OA controls. Other sources (embryonic, synovial, peripheral blood, dental pulp, cartilage, meniscus and muscle-derived products) were investigated in fewer preclinical studies. The risk of bias was low in 42% of items, unclear in 49%, and high in 9% of items.

CONCLUSION

Interest in cell-based injectable therapies for OA treatment is soaring, particularly for alternatives to bone marrow and adipose tissue. While expanded umbilical cord mesenchymal stem cells reported auspicious disease-modifying effects in preventing OA progression in animal models, placenta/amniotic tissue also reported deleterious effects on OA joints. Lower evidence has been found for other cellular sources such as embryonic, synovial, peripheral blood, dental-pulp, cartilage, meniscus, and muscle-derived products.

LEVEL OF EVIDENCE

Level II.

Single high-dose intravenous injection of Wharton's jelly-derived mesenchymal stem cell exerts protective effects in a rat model of metabolic syndrome

BACKGROUND

Metabolic syndrome (MetS) is a significant epidemiological problem worldwide. It is a pre-morbid, chronic and low-grade inflammatory disorder that precedes many chronic diseases. Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) could be used to treat MetS because they express high regenerative capacity, strong immunomodulatory properties and allogeneic biocompatibility. This study aims to investigate WJ-MSCs as a therapy against MetS in a rat model.

METHODS

Twenty-four animals were fed with high-fat high-fructose (HFHF) diet ad libitum. After 16 weeks, the animals were randomised into treatment groups (n = 8/group) and received a single intravenous administration of vehicle, that is, 3 × 106 cells/kg or 10 × 106 cells/kg of WJ-MSCs. A healthy animal group (n = 6) fed with a normal diet received the same vehicle as the control (CTRL). All animals were periodically assessed (every 4 weeks) for physical measurements, serum biochemistry, glucose tolerance test, cardiovascular function test and whole-body composition. Post-euthanasia, organs were weighed and processed for histopathology. Serum was collected for C-reactive protein and inflammatory cytokine assay.

RESULTS

The results between HFHF-treated groups and healthy or HFHF-CTRL did not achieve statistical significance (α = 0.05). The effects of WJ-MSCs were masked by the manifestation of different disease subclusters and continuous supplementation of HFHF diet. Based on secondary analysis, WJ-MSCs had major implications in improving cardiopulmonary morbidities. The lungs, liver and heart show significantly better histopathology in the WJ-MSC-treated groups than in the untreated CTRL group. The cells produced a dose-dependent effect (high dose lasted until week 8) in preventing further metabolic decay in MetS animals.

CONCLUSIONS

The establishment of safety and therapeutic proof-of-concept encourages further studies by improving the current therapeutic model.

Facing the Challenges in the COVID-19 Pandemic Era: From Standard Treatments to the Umbilical Cord-Derived Mesenchymal Stromal Cells as a New Therapeutic Strategy

Coronavirus disease 2019 (COVID-19), the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which counts more than 650 million cases and more than 6.6 million of deaths worldwide, affects the respiratory system with typical symptoms such as fever, cough, sore throat, acute respiratory distress syndrome (ARDS), and fatigue. Other nonpulmonary manifestations are related with abnormal inflammatory response, the "cytokine storm", that could lead to a multiorgan disease and to death. Evolution of effective vaccines against SARS-CoV-2 provided multiple options to prevent the infection, but the treatment of the severe forms remains difficult to manage. The cytokine storm is usually counteracted with standard medical care and anti-inflammatory drugs, but researchers moved forward their studies on new strategies based on cell therapy approaches. The perinatal tissues, such as placental membranes, amniotic fluid, and umbilical cord derivatives, are enriched in mesenchymal stromal cells (MSCs) that exert a well-known anti-inflammatory role, immune response modulation, and tissue repair. In this review, we focused on umbilical-cord-derived MSCs (UC-MSCs) used in in vitro and in vivo studies in order to evaluate the weakening of the severe symptoms, and on recent clinical trials from different databases, supporting the favorable potential of UC-MSCs as therapeutic strategy.

Human Wharton's Jelly Mesenchymal Stem Cell Secretome Modifies the Processes of Neuroprotection and Epithelial-Mesenchymal Transition in Retinal Pigment Epithelium at Transcriptional Level

BACKGROUND

Retinal pigment epithelium (RPE) cells are potential targets for treating retinal detachment (RD) and proliferative vitreoretinopathy (PVR), considering the importance of neuroprotection and epithelial-mesenchymal transition (EMT) of RPE in these conditions. This study investigated the effect of human Wharton's jelly mesenchymal stem cell secretome (WJMSC-S) on the expression of genes involved in both neuroprotection and EMT in RPE cells in vitro (TRKB, MAPK, PI3K, BDNF, and NGF).

METHODS

RPE cells from passages 5-7 were treated with WJMSC-S (or the vehicle culture medium as control) for 24 h at 37◦C and subsequently subjected to RNA extraction and cDNA synthesis. Gene expression level was evaluated using real-time PCR in the treated versus control cells.

RESULTS

The results of our study showed that WJMSC-S led to a significant downregulation in three out of five studied gene expression (MAPK, TRKB, and NGF), and simultaneously, remarkably upregulated the expression of the BDNF gene.

CONCLUSIONS

According to the present data, WJMSC-S can affect the EMT and neuroprotection processes at the mRNA level by suppressing EMT and promoting neuroprotection in RPE cells. This finding may have positive clinical implications in the context of RD and PVR.

The effects of mesenchymal stem cells on the chemotherapy of colorectal cancer

Colorectal cancer (CRC) has been the third commonest cancer in the world. The prognosis of patients with CRC is related to the molecular subtypes and gene mutations, which is prone to recurrence, metastasis, and drug resistance. Mesenchymal stem cells (MSCs) are a group of progenitor ones with the capabilities of self-renewal， multi-directional differentiation, and tissue re-population, which could be isolated from various kinds of tissues and be differentiated into diverse cell types. In recent years, MSCs are applied for mechanisms study of tissue repairing, graft-versus-host disease (GVHD) and autoimmune-related disease, and tumor development, with the advantages of anti-inflammation, multi-lineage differentiation, and homing capability. Integrating the chemotherapy and MSCs therapy might provide a novel treatment approach for CRC patients. In this review, we summarize the current progress in the integrated treatment of integrating the MSCs and chemotherapy for CRC.

A chemically defined biomimetic surface for enhanced isolation efficiency of high-quality human mesenchymal stromal cells under xenogeneic/serum-free conditions

BACKGROUND AIMS

Mesenchymal stromal cells (MSCs) are one of the most frequently used cell types in regenerative medicine and cell therapy. Generating sufficient cell numbers for MSC-based therapies is constrained by (i) their low abundance in tissues of origin, which imposes the need for significant ex vivo cell expansion; (ii) donor-specific characteristics, including MSC frequency/quality, that decline with disease state and increasing age; and (iii) cellular senescence, which is promoted by extensive cell expansion and results in decreased therapeutic functionality. The final yield of a manufacturing process is therefore primarily determined by the applied isolation procedure and its efficiency in isolating therapeutically active cells from donor tissue. To date, MSCs are predominantly isolated using media supplemented with either serum or its derivatives, which poses safety and consistency issues.

METHODS

To overcome these limitations while enabling robust MSC production with constant high yield and quality, the authors developed a chemically defined biomimetic surface coating called isoMATRIX (denovoMATRIX GmbH, Dresden, Germany) and tested its performance during isolation of MSCs.

RESULTS

The isoMATRIX facilitates the isolation of significantly higher numbers of MSCs in xenogeneic (xeno)/serum-free and chemically defined conditions. The isolated cells display a smaller cell size and higher proliferation rate than those derived from a serum-containing isolation procedure and a strong immunomodulatory capacity. The high proliferation rates can be maintained up to 5 passages after isolation and cells even benefit from a switch towards a proliferation-specific MSC matrix (myMATRIX MSC) (denovoMATRIX GmbH, Dresden, Germany).

CONCLUSION

In sum, isoMATRIX promotes enhanced xeno/serum-free and chemically defined isolation of human MSCs and supports consistent and reliable cell performance for improved stem cell-based therapies.

Current Status of Mesenchymal Stem/Stromal Cells for Treatment of Neurological Diseases

Neurological disorders include a wide spectrum of clinical conditions affecting the central and peripheral nervous systems. For these conditions, which affect hundreds of millions of people worldwide, generally limited or no treatments are available, and cell-based therapies have been intensively investigated in preclinical and clinical studies. Among the available cell types, mesenchymal stem/stromal cells (MSCs) have been widely studied but as yet no cell-based treatment exists for neurological disease. We review current knowledge of the therapeutic potential of MSC-based therapies for neurological diseases, as well as possible mechanisms of action that may be explored to hasten the development of new and effective treatments. We also discuss the challenges for culture conditions, quality control, and the development of potency tests, aiming to generate more efficient cell therapy products for neurological disorders.

Concentrated Bone Marrow Aspirate Is More Cellular and Proliferative When Harvested From the Posterior Superior Iliac Spine Than the Proximal Humerus

PURPOSE

The purpose of this study is to determine whether concentrated bone marrow aspirate (cBMA) from the posterior superior iliac spine (PSIS) or proximal humerus (PH) produces a more productive cellular harvest in patients undergoing arthroscopic rotator cuff repair.

METHODS

Patients under 80 years old undergoing surgery for arthroscopic rotator cuff repair were enrolled. Two 60 mL aliquots of BMA were harvested from each subject, one from the PSIS and one from the PH. Each aliquot was processed independently to create cBMA. Cellular composition was determined using an automated hemocytometer and proliferative potential was studied with colony forming unit (CFU) assays.

RESULTS

Twelve patients were recruited (7 male, 5 female). The average age was 64.3 years (range 46.1-77.25 years) with body mass index of 26.8 (range 20.0-34.3). The average total nucleated cells (TNC) from PH was 18.7 × 10⁶ cells/mL (95% confidence interval [CI], 4.4-33.0; standard deviation [SD], 24.8) with 3.9 CFU/mL (95% CI, 0.3-7.5, SD, 5.7). The average TNC count from the PSIS was 55.9 × 10⁶ cells/mL (95% CI, 25.3-86.4; SD, 52.9) with 32.5 CFU/mL (95% CI, 11.5-53.5; SD, 33.1). The PSIS had a 3.0 times greater total nucleated cell yield (P = .014) and 8.3 times greater number of CFU/mL (P = .024) when compared to the PH. The average harvest time from the PSIS was 5.6 minutes and from the PH was 11.0 minutes (P = .043); harvest time did not account for additional time to prep and drape the PSIS.

CONCLUSIONS

The cBMA harvested from the PSIS resulted in a 3.0 times greater cellular yield and an 8.3 times greater proliferative product than cBMA from the PH.

CLINICAL RELEVANCE

When a more cellular cBMA product is sought to augment rotator cuff tear repair surgery, the PSIS is the preferred site for harvest.

Umbilical Cord-Derived Wharton's Jelly for Regenerative Medicine Applications: A Systematic Review

Musculoskeletal ailments affect millions of people around the world and place a high burden on healthcare. Traditional treatment modalities are limited and do not address underlying pathologies. Mesenchymal stem cells (MSCs) have emerged as an exciting therapeutic alternative and Wharton’s jelly-derived mesenchymal stem cells (WJSCs) are some of these. This review reports the clinical and functional outcomes of the applications of WJSCs in orthopedic surgery. A systematic review was conducted utilizing the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The studies that used culture-expanded, mesenchymal stem or stromal cells, MSCs and/or connective tissues procured from Wharton’s jelly (WJ), from January 2010 to October 2021, were included. Conventional non-operative therapies and placebos were used as comparisons. Six studies that directly discussed WJSCs use in an animal model or the basic scientific testing using an injury model were identified. Five publications studied cartilage injury, three studied degenerative disc disease, one was related to osteoarthritis, and one was related to osteochondral defects. The results of these studies suggested the benefits of WJSCs in the management of these orthopedic pathologies. To adequately assess the safety and efficacy of WJSCs in orthopedic surgery, further randomized controlled clinical studies are necessary.

Food and Drug Administration's Position on Commonly Injected Biologic Materials in Orthopaedic Surgery

The use of biologically based therapies is becoming a popular less-invasive therapy for relieving pain and promoting tissue regeneration. The most commonly used biologics are autologous adipose-derived products, bone marrow aspirations, and platelet-rich plasma (PRP). Birth tissue is a common allogenic source of biologics, including umbilical cord, placental membranes, and amniotic fluid. Injected biologics, depending on the indication and how they are processed, formulated, delivered, and promoted, can be subject to different regulatory pathways. The aim of this review is to provide an overview of these products and procedures and educate the musculoskeletal community about the relevant current Food and Drug Administration (FDA) regulations.

3D Biomimetic Scaffold for Growth Factor Controlled Delivery: An In-Vitro Study of Tenogenic Events on Wharton's Jelly Mesenchymal Stem Cells

The present work described a bio-functionalized 3D fibrous construct, as an interactive teno-inductive graft model to study tenogenic potential events of human mesenchymal stem cells collected from Wharton’s Jelly (hWJ-MSCs). The 3D-biomimetic and bioresorbable scaffold was functionalized with nanocarriers for the local controlled delivery of a teno-inductive factor, i.e., the human Growth Differentiation factor 5 (hGDF-5). Significant results in terms of gene expression were obtained. Namely, the up-regulation of Scleraxis (350-fold, p ≤ 0.05), type I Collagen (8-fold), Decorin (2.5-fold), and Tenascin-C (1.3-fold) was detected at day 14; on the other hand, when hGDF-5 was supplemented in the external medium only (in absence of nanocarriers), a limited effect on gene expression was evident. Teno-inductive environment also induced pro-inflammatory, (IL-6 (1.6-fold), TNF (45-fold, p ≤ 0.001), and IL-12A (1.4-fold)), and anti-inflammatory (IL-10 (120-fold) and TGF-β1 (1.8-fold)) cytokine expression upregulation at day 14. The presented 3D construct opens perspectives for the study of drug controlled delivery devices to promote teno-regenerative events.

Treatment of acute ischemic stroke by minimally manipulated umbilical cord-derived mesenchymal stem cells transplantation: A case report

BACKGROUND

Stroke is one of the major causes of disability and death worldwide. Some treatments for stroke exist, but existing treatment methods have limitations such as difficulty in the regeneration of damaged neuronal cells of the brain. Recently, mesenchymal stem cells (MSCs) have been studied as a therapeutic alternative for stroke, and various preclinical and case studies have been reported.

CASE SUMMARY

A 55-year-old man suffered an acute stroke, causing paralysis in the left upper and lower limbs. He intravenously transplanted the minimally manipulated human umbilical cord-derived MSCs (MM-UC-MSCs) twice with an 8-d interval. At 65 wk after transplantation, the patient returned to his previous occupation as a veterinarian with no adverse reactions.

CONCLUSION

MM-UC-MSCs transplantation potentially treats patients who suffer from acute ischemic stroke.

Mesenchymal stem/stromal cells as next-generation drug delivery vehicles for cancer therapeutics

INTRODUCTION

Drug delivery to solid tumors remains a significant therapeutic challenge. Mesenchymal stem/stromal cells (MSCs) home to tumor tissues and can be employed as tumor targeted drug/gene delivery vehicles. Reportedly, therapeutic gene- or anti-cancer drug-loaded MSCs have shown remarkable anti-tumor effects in preclinical studies, and some clinical trials for assessing therapeutic MSCs in patients with cancer have been registered.

AREAS COVERED

In the present review, we first discuss the source and interdonor heterogeneity of MSCs, their tumor-homing mechanism, and the route of MSC administration in MSC-based cancer therapy. We then summarize the therapeutic applications of MSCs as a drug delivery vehicle for therapeutic genes or anti-cancer drugs and the drug delivery mechanism from drug-loaded MSCs to cancer cells.

EXPERT OPINION

Although numerous preclinical studies have revealed significant anti-tumor effects, several clinical trials assessing MSC-based cancer gene therapy have failed to demonstrate corroborative results, documenting limited therapeutic effects. Notably, a successful clinical outcome with MSC-based cancer therapy would require the interdonor heterogeneity of administered MSCs to be resolved, along with improved tumor-homing efficiency and optimized drug delivery efficiency from MSCs to cancer cells.

Evaluation of immediate and short-term efficacy of DualStim therapy with and without intracavernosal umbilical cord-derived Wharton's jelly in patients with erectile dysfunction: Study protocol for a randomized controlled trial

Introduction

Erectile dysfunction (ED) affects a significant portion of the United States population and causes negative psychological burdens that affects men and their partner's quality of life and satisfaction. Extracorporeal shock therapy (ESWT) utilizing focused ESWT and radial ESWT in Low-intensity shock wave therapy has been used to treat ED with some success. Wharton's Jelly (WJ) is a biologic substance with large amounts of stem cells, growth factors, cytokines and extracellular components. The use of combined focused and radial ESWT (DualStim therapy) with injected WJ have potential uses in ED that may have advantages over current treatments.

Materials

A randomized, single-blinded, controlled clinical trial will be conducted to evaluate the efficacy and safety of DualStim therapy and intracavernosal injection of WJ in moderate to severe ED. A total of 60 patients with moderate to severe ED will be enrolled and treated with DualStim therapy with intracavernosal injection of WJ or saline for a period of 7 weeks. The International Index of Erectile Function – Erectile Function score will be used to gauge the treatment related changes in relation to the subject's baseline. The scores will be recorded at baseline and compared to follow-ups 1,3 and 6 months post-treatment. Any adverse events or severe adverse events will be recorded in the corresponding case report forms. Sexual Encounter Profile, as well as the Global Assessment Questionnaire and the Erection Hardness Score will be used to determine the sexual activity improvement from baseline leading to optimal penetration at follow-ups 1,3 and 6 months post-treatment.

Discussion

This clinical trial is one of the first studies to determine the immediate and short-term efficacy of DualStim therapy, with and without intracavernosal injection of formulated umbilical cord-derived WJ to improve and/or restore erectile function in patients with moderate to severe ED. This study will also provide insight into the safety and efficacy of WJ. We anticipate clinically significant improvement in patients suffering from moderate and severe ED treated with DualStim therapy with WJ compared to their baseline and DualStim with saline.

Alopecia treatment using minimally manipulated human umbilical cord-derived mesenchymal stem cells: Three case reports and review of literature

BACKGROUND

Alopecia areata (AA) is a common autoimmune disease characterized by hair loss. AA appears in extensive forms, such as progressive and diffusing hair loss (diffuse AA), a total loss of scalp hair (alopecia totalis), and complete loss of hair over the entire body (alopecia universalis). Recently, mesenchymal stem cells (MSCs) have been identified as a therapeutic alternative for autoimmune diseases. For this reason, preclinical and case studies of AA and related diseases using MSCs have been conducted.

CASE SUMMARY

Case 1: A 55-year-old woman suffered from AA in two areas of the scalp. She was given 15 rounds of minimally manipulated umbilical cord-MSCs (MM-UC-MSCs) over 6 mo. The AA gradually improved 3 mo after the first round. The patient was cured, and AA did not recur. Case 2: A 30-year-old woman, with history of local steroid hormone injections, suffered from AA in one area on the scalp. She was given two rounds of MM-UC-MSCs over 1 mo. The AA immediately improved after the first round. The patient was cured, and AA did not recur. Case 3: A 20-year-old woman, who was diagnosed with alopecia universalis at the age of 12, was given 14 rounds of MM-UC-MSCs over 12 mo. Her hair began to grow about 3 mo after the first round. The patient was cured, and alopecia universalis did not recur.

CONCLUSION

MM-UC-MSC transplantation potentially treats patients who suffer from AA and related diseases.

Reduction of Graft-versus-Host-Disease in NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ (NSG) Mice by Cotransplantation of Syngeneic Human Umbilical Cord-Derived Mesenchymal Stromal Cells

Graft-versus-host disease (GVHD) is one of the major complications following hematopoietic stem cell transplantation, which remains the sole curative therapy for many malignant diseases of the hematopoietic system. The immunomodulatory potential of mesenchymal stromal cells (MSCs) to treat GVHD is currently being tested in various preclinical and clinical trials. Because the results of the preclinical and clinical trials on the use of MSCs to treat GVHD have not been consistent, we analyzed the potential beneficial effects of syngeneic versus allogenic treatment, culture expansion of MSCs, and various MSC cell doses and time points of MSC transplantation in a murine GVHD model. We established the murine GVHD model based on the transplantation of umbilical cord blood-derived hematopoietic stem cells (UC-HSCs) and used this model to assess the therapeutic potential of umbilical cord blood-derived MSCs (UC-MSCs). The use of HSC and MSC populations derived from the same donor allowed us to exclude third-party cells and test the UC-HSCs and UC-MSCs in a matched setting. Moreover, we were able to compare various doses, transplantation time points, and the influence of culture expansion of MSCs on the impact of treatment. This resulted in 16 different treatment groups. The most efficient setting for treatment of UC-HSC-induced GVHD reactions was based on the simultaneous administration of 1 × 10⁶ culture-expanded, syngeneically matched UC-MSCs. This therapy effectively reduced the number of CD8⁺ T cells in the blood, protected the mice from weight loss, and prolonged their survival until the end of observation period. Taken together, our data show beneficial effects of (1) syngeneic over allogeneic UC-HSCs and UC-MSCs, (2) culture-expanded cells over freshly isolated primary cells, (3) simultaneous over sequential administration, and (4) high doses of UC-MSCs. The animal model of GVHD established here is now available for more detailed studies, including a comparative analysis of the efficacy of MSCs derived from alternative sources, such as adipose tissue and bone marrow.

Quality by design to define critical process parameters for mesenchymal stem cell expansion

Stem cell-based therapeutic products could be the key to treat the deadliest current pathologies, ranging from neuro-degenerative to respiratory diseases. However, in order to bring these innovative therapeutics to a commercialization stage, reproducible manufacturing of high quality cell products is required. Although advances in cell culture techniques have led to more robust production processes and dramatically accelerated the development of early-phase clinical studies, challenges remain before regulatory approval, particularly to define and implement science-based quality standards (essential pre-requisites for national health agencies). In this regard, using new methodologies, such as Quality By Design (QBD), to build the production process around drug quality, could significantly reduce the chance of product rejection. This review-based work aims to perform a QBD approach to Mesenchymal Stem Cell (MSC) manufacturing in standard two-dimensional flasks, using published studies which have determined the impact of individual process parameters on defined Critical Quality Attributes (CQA). Along with this bibliographic analysis, parameter criticality was determined during the two main manufacturing stages (cell extraction and cell amplification) along with an overall classification in view of identifying the Critical Process Parameters (CPP). The analysis was performed in view of an improved standardization between research teams, and should contribute to reduce the gap towards compliant Good Manufacturing Practice (cGMP) manufacturing.

Elevation of Peripheral Blood CD34+ and Platelet Levels After Exercise With Cooling and Compression

Purpose

To analyze the cellular response and chemokine profiles following exercise using cooling and blood flow restriction on the Vasper system.

Methods

Healthy male patients between the ages of 20 and 39 years were recruited. Testing was performed on the Vasper system, a NuStep cross-trainer with concomitant 4-limb venous compression with proximal arm cuffs at 40 mm Hg and proximal leg cuffs at 65 mm Hg. A cooling vest and cooling mat (8.3°C) were used. A 7-minute warm-up followed by alternating 30- and 60-second sprints with 1.5 and 2 minutes of active recovery, respectively, between each sprint. Peripheral blood was drawn before exercise, immediately following exercise (T20), 10 minutes after the first post-exercise blood draw (T30), and then every 30 minutes (T60, T90, T120, T150, T180). A blood draw occurred at 24 hours’ postexercise. Complete blood count, monoclonal flow cytometry for CD34+, and enzyme-linked immunosorbent assay were used to analyze the samples.

Results

Sixteen healthy male patients (29.5 ± 4.5years, 1.78 ± 0.05m, 83.7 ± 11.4 kg) were enrolled. There was an immediate, temporary increase in white blood cell counts, marked by an increase in lymphocyte differential (38.3 ± 6.5 to 44.3 ± 9.0%, P = .001), decrease in neutrophil differential (47.8 ± 6.6 to 42.0 ± 9.1%, P < .001), and platelets (239.5 ± 57.2 to 268.6 ± 86.3 K⋅μL^–1, P = .01). Monocytes significantly decreased from PRE to T90 (9.8 ± 1.1 to 8.9 ± 1.1K/μL, P < .001) and T120 (8.9 ± 1.1 K/μL, P < .0001). There was a significant increase in CD34+ cells (3.9 ± 2.0 to 5.3 ± 2.8 cells⋅μL^–1, P < .001). No detectable differences in measured cytokine levels of interleukin (IL)-10, IL-6, granulocyte-macrophage colony-stimulating factor , IL-1ra, tumor necrosis factor-α, or IL-2 were observed.

Conclusions

A significant elevation of peripheral blood CD34+ and platelet levels immediately following the exercise session was observed; however, there was no effect on peripheral circulation of IL-10, IL-6, IL-1ra, tumor necrosis factor-α, or IL-2.

Clinical Relevance

Exercise can be considered as a way to manipulate point-of-care blood products like platelet-rich plasma and may increase product yield.

Circ6401, a novel circular RNA, is implicated in repair of the damaged endometrium by Wharton's jelly-derived mesenchymal stem cells through regulation of the miR-29b-1-5p/RAP1B axis

Background

Accumulating evidence indicates that mesenchymal stem cells (MSCs) exert tissue repair effects and therapeutic angiogenesis through their noncoding RNAs (ncRNAs). Our previous studies showed that MSCs derived from Wharton’s jelly (WJ-MSCs) can ameliorate damaged human endometrium by promoting angiogenesis. There is limited information on the functions and mechanism of ncRNAs in MSC-induced endometrial repair, and additional studies are needed for more insights.

Methods

Here, WJ-MSCs were cocultured with or without endometrial stromal cells (ESCs) damaged by mifepristone (cocultured group versus non-cocultured group). TUNEL staining assays, EdU proliferation assays, flow cytometry apoptosis assays, and western blot assays were performed to observe the reparative effect of WJ-MSCs on damaged ESCs. Subsequently, circular RNA (circRNA) and microRNA microarrays were performed between the two groups. A subset of top upregulated circRNAs was validated by qRT-PCR. The functions of circ6401 (hsa_circ_0006401) in WJ-MSCs were investigated using lentivirus-mediated circRNA overexpression assays. The subcellular localization of circ6401 and miR-29b-1-5p in WJ-MSCs was identified by double RNA fluorescence in situ hybridization. Dual-luciferase reporter assays and western blot assays were performed to elucidate the regulatory mechanisms among circ6401, miR-29b-1-5p, and RAP1B.

Results

WJ-MSCs significantly improved ESC proliferation and upregulated the expression of vascular angiogenesis markers. Circ6401 was upregulated in WJ-MSCs cocultured with damaged ESCs, while miR-29b-1-5p was significantly downregulated. Furthermore, circ6401 was found to bind to miR-29b-1-5p and prevent it from decreasing the level of RAP1B, a crucial protein involved in the VEGF signaling pathway, which promoted angiogenesis and stimulated the proliferation of ESCs.

Conclusions

Our results showed the abundance and regulation profiles of ncRNAs of WJ-MSCs during repair of damaged ESCs and, for the first time, clarified the underlying mechanism by which circ6401 promotes endometrial repair by WJ-MSCs; thus, demonstrating that circ6401 may serve as a potential therapeutic target.

Umbilical cord-derived Wharton's jelly for regenerative medicine applications in orthopedic surgery: a systematic review protocol

BACKGROUND

Musculoskeletal injuries and conditions affect millions of individuals. These ailments are typically managed by immobilization, physiotherapy, or activity modification. Regenerative medicine has experienced tremendous growth in the past decades, especially in musculoskeletal medicine. Umbilical cord-derived Wharton's jelly is an exciting new option for such therapies. Wharton's jelly is a connective tissue located within the umbilical cord largely composed of mesenchymal stem cells and extracellular matrix components, including collagen, chondroitin sulfate, hyaluronic acid, and sulfated proteoglycans. Wharton's jelly is a promising and applicable biologic source for orthopedic regenerative application.

METHODS

A systematic search will be conducted in PubMed, ScienceDirect, and Google Scholar databases of English, Italian, French, Spanish, and Portuguese language articles published to date. References will be screened and assessed for eligibility by two independent reviewers as per PRISMA guidelines. Articles will be considered without exclusion to sex, activity, or age. Studies will be included if they used culture-expanded, mesenchymal stem/stromal cells of mesenchymal stem cells and/or connective tissue obtained from Wharton's jelly. Studies will be excluded if Wharton's jelly is not the sole experimental examined cell type. Placebos, conventional non-operative therapies including steroid injections, exercise, and NSAIDs will be compared. The study selection process will be performed independently by two reviewers using a reference software. Data synthesis and meta-analysis will be performed separately for clinical and pre-clinical studies.

DISCUSSION

The results will be published in relevant peer-reviewed scientific journals. Investigators will present results at national or international conferences.

TRIAL REGISTRATION

The protocol was registered on PROSPERO international prospective register of systematic reviews prior to commencement, CRD42020182487 .

Quantification and Qualification of Stem Cells From Blood After Mobilization With Filgrastim, and Concentration Using a Platelet-Rich Plasma System

PURPOSE

To determine the cellular composition of a product created with peripheral blood harvested after systemic mobilization with filgrastim and processed with one point-of-care blood concentrating system, i.e., a platelet-rich plasma (PRP) system. The second purpose was to compare mobilized platelet-rich plasma (M-PRP) with a concentrated bone marrow aspirate (cBMA) and a PRP created from the same subjects with the same PRP system.

METHODS

Ten healthy volunteer subjects were recruited for collection and analysis of 3 tissue sources: non-treated peripheral blood, bone marrow aspirate, and filgrastim-mobilized peripheral blood, involving 4 doses of weight-based filgrastim. One point-of-care blood and bone marrow concentrating system was used to create 3 products: PRP, cBMA, and M-PRP. Automated hematologic analysis was performed on all products to quantify total red blood cells, white blood cells (WBCs), monocyte, platelet, and hematopoietic progenitor cell (HPC) concentrations. Flow cytometry was used to determine hematopoietic and mesenchymal progenitor cell populations. Lastly, concentrates were cultured and fibroblast colony-forming units (CFU-F) and morphology of adherent cells were evaluated.

RESULTS

M-PRP contained a greater concentration of WBC (mean difference = 53.2 k/μL; P < .0001), monocytes (mean difference = 8.3 k/μL; P = .002), and a trend toward a greater concentration of HPC (mean difference = 200.5 /μL; P = .060) when compared with PRP. M-PRP contained a greater concentration of monocytes (mean difference = 5.5 k/μL; P = .017) and a trend toward a greater concentration of platelets (mean difference = 348 k/μL; P = .051) and HPC (mean difference = 193.4 /μL; P = .068) when compared with cBMA. M-PRP had a similar concentration of platelets to PRP (mean difference = 110 k/μL; P = .051) and PRP had a greater concentration than cBMA (mean difference = 458 k/μL; P = .003). cBMA remained the only product capable of producing CFU-Fs (446 ± 247 /mL) as neither the M-PRP nor PRP produced CFU-Fs. M-PRP produced colonies consistent with WBC.

CONCLUSIONS

M-PRP, produced with filgrastim mobilized blood and a proprietary PRP system, contained more total WBCs, monocytes, platelets, and HPCs than cBMA and more WBCs, monocytes, and HPCs than PRP.

CLINICAL RELEVANCE

Filgrastim mobilized PRP may be an alternative to cBMA for use as a point-of-care product for orthopaedic treatments.

Immediate Intracoronary Delivery of Human Umbilical Cord Mesenchymal Stem Cells Reduces Myocardial Injury by Regulating the Inflammatory Process Through Cell-Cell Contact with T Lymphocytes

Inflammatory response regulation is a mechanism through which human umbilical cord mesenchymal stem cells (HUCMSCs) improve myocardial ischemia reperfusion injury (IRI); however, the timing of HUCMSC delivery to achieve maximum effectiveness is controversial. To investigate the effects of HUCMSC delivery on the acute inflammatory stage of IRI, we transplanted HUCMSCs or HUCMSCs with cyclosporin A (CsA) through the coronary artery simultaneously during ischemia reperfusion in pigs. Ferumoxytol-labeled HUCMSCs (HUCMSC), HUCMSCs with cyclosporin A (HUCMSC+CsA), and PBS (control) groups were investigated to evaluate the homing of transplanted cells and changes in infarct features, cardiac activity, and inflammatory response at three time points post-transplantation. Animals were sacrificed 2 weeks later for histological analysis of the hearts. We detected Prussian blue-dyed granules distributed around T lymphocyte clusters in the infarct area in the HUCMSC group. Infarct size and collagen deposition in the infarct area were lower in the HUCMSC group than in the control and HUCMSC+CsA groups. Cardiac function was mildly impaired in both the control and HUCMSC groups, whereas added CsA had a more severe impact. The levels of proinflammatory markers were lower in the HUCMSC group than in the control group at 24-h follow-up, and the difference was more significant after adding CsA. There were more CD3⁺ T lymphocytes and Foxp3⁺ Tregs in the HUCMSC group infarct area than in the other two groups. Proliferation rate of T lymphocytes was higher in the HUCMSC group than in the other two groups. Indirect co-culture experiments in vitro showed that MSCs promoted the generation of CD4⁺CD25⁺ Foxp3⁺Tregs through a paracrine mechanism. These results indicate that immediate intracoronary delivery of HUCMSCs after ischemia reperfusion can reduce acute myocardial IRI and promote myocardial repair, mainly through T lymphocyte interactions to regulate the intense inflammatory response during the acute inflammatory stage.

Bone marrow-derived from the human femoral shaft as a new source of mesenchymal stem/stromal cells: an alternative cell material for banking and clinical transplantation

BACKGROUND

Mesenchymal stem/stromal cells (MSC) are commonly used in regenerative medicine. Among different tissues, iliac crest bone marrow (BM) represents the most exploited source, but its disadvantages are a painful aspiration procedure and low cell number. An alternative, readily available source of MSC for research would be beneficial for regenerative medicine development. This work aimed to propose a new source of bone marrow isolation in which the femoral shaft is taken during total hip arthroplasty (THA).

METHODS

In preliminary experiments, three different gradient methods for cell separation (Ficoll-Paque 1.078 g/mL, 17% sucrose gradient, BM seeding fraction) were tested with regard to the time of primary culture, initial cell number, the phenotype, and morphology of MSC. Then human bone marrow MSC derived from two different sources, iliac crest aspirate (BM-MSCi) or femoral shaft (BM-MSCt), were analyzed in terms of cell number and colony-forming ability followed by differentiation potential of MSC into osteo-, chondro-, and adipogenic lineages as well as mRNA expression of a variety of cytokines and growth factors.

RESULTS

Our studies showed that MSC isolated from the bone marrow of two different sources and cultured under appropriate conditions had similar characteristics and comparable propensity to differentiate into mesodermal cells. MSC derived from BM-MSCi or BM-MSCt expressed various growth factors. Interestingly, the expression of EGF, FGF, IGF, and PDGF-A was much higher in BM-MSCt than BM-MSCi.

CONCLUSIONS

The results of our study demonstrate that human MSC isolated from the BM of the femoral shaft have similar biological characteristics as MSC derived from the iliac crest, suggesting the femoral shaft as a possible alternative source for mesenchymal stem/stromal cells.

The Role of Pref-1 during Adipogenic Differentiation: An Overview of Suggested Mechanisms

Obesity contributes significantly to the global health burden. A better understanding of adipogenesis, the process of fat formation, may lead to the discovery of novel treatment strategies. However, it is of concern that the regulation of adipocyte differentiation has predominantly been studied using the murine 3T3-L1 preadipocyte cell line and murine experimental animal models. Translation of these findings to the human setting requires confirmation using experimental models of human origin. The ability of mesenchymal stromal/stem cells (MSCs) to differentiate into adipocytes is an attractive model to study adipogenesis in vitro. Differences in the ability of MSCs isolated from different sources to undergo adipogenic differentiation, may be useful in investigating elements responsible for regulating adipogenic differentiation potential. Genes involved may be divided into three broad categories: early, intermediate and late-stage regulators. Preadipocyte factor-1 (Pref-1) is an early negative regulator of adipogenic differentiation. In this review, we briefly discuss the adipogenic differentiation potential of MSCs derived from two different sources, namely adipose-derived stromal/stem cells (ASCs) and Wharton’s Jelly derived stromal/stem cells (WJSCs). We then discuss the function and suggested mechanisms of action of Pref-1 in regulating adipogenesis, as well as current findings regarding Pref-1’s role in human adipogenesis.

Human Wharton's Jelly-Cellular Specificity, Stemness Potency, Animal Models, and Current Application in Human Clinical Trials

Stem cell therapies offer a great promise for regenerative and reconstructive medicine, due to their self-renewal and differentiation capacity. Although embryonic stem cells are pluripotent, their utilization involves embryo destruction and is ethically controversial. Therefore, adult tissues that have emerged as an alternative source of stem cells and perinatal tissues, such as the umbilical cord, appear to be particularly attractive. Wharton's jelly, a gelatinous connective tissue contained in the umbilical cord, is abundant in mesenchymal stem cells (MSCs) that express CD105, CD73, CD90, Oct-4, Sox-2, and Nanog among others, and have the ability to differentiate into osteogenic, adipogenic, chondrogenic, and other lineages. Moreover, Wharton's jelly-derived MSCs (WJ-MSCs) do not express MHC-II and exhibit immunomodulatory properties, which makes them a good alternative for allogeneic and xenogeneic transplantations in cellular therapies. Therefore, umbilical cord, especially Wharton's jelly, is a promising source of mesenchymal stem cells.

Umbilical cord-derived Wharton's jelly for regenerative medicine applications

Background

The last decade has seen an explosion in the interest in using biologics for regenerative medicine applications, including umbilical cord-derived Wharton’s Jelly. There is insufficient literature assessing the amount of growth factors, cytokines, hyaluronic acid, and extracellular vesicles including exosomes in these products. The present study reports the development of a novel Wharton’s jelly formulation and evaluates the presence of growth factors, cytokines, hyaluronic acid, and extracellular vesicles including exosomes.

Methods

Human umbilical cords were obtained from consenting caesarian section donors. The Wharton’s jelly was then isolated from the procured umbilical cord and formulated into an injectable form. Randomly selected samples from different batches were analyzed for sterility testing and to quantify the presence of growth factors, cytokines, hyaluronic acid, and extracellular vesicles.

Results

All samples passed the sterility test. Growth factors including IGFBP 1, 2, 3, 4, and 6, TGF-α, and PDGF-AA were detected. Several immunomodulatory cytokines, such as RANTES, IL-6R, and IL-16, were also detected. Pro-inflammatory cytokines MCSFR, MIP-1a; anti-inflammatory cytokines TNF-RI, TNF-RII, and IL-1RA; and homeostatic cytokines TIMP-1 and TIMP-2 were observed. Cytokines associated with wound healing, ICAM-1, G-CSF, GDF-15, and regenerative properties, GH, were also expressed. High concentrations of hyaluronic acid were observed. Particles in the extracellular vesicle size range were also detected and were enclosed by the membrane, indicative of true extracellular vesicles.

Conclusion

There are numerous growth factors, cytokines, hyaluronic acid, and extracellular vesicles present in the Wharton’s jelly formulation analyzed. The amount of these factors in Wharton’s jelly is higher compared with other biologics and may play a role in reducing inflammation and pain and augment healing of musculoskeletal injuries.

Novel Use of Cryopreserved Ultra-thick Human Amniotic Membrane for Management of Anophthalmic Socket Contracture

PURPOSE

To describe the use of cryopreserved ultra-thick human amniotic membrane for management of anophthalmic socket contracture.

METHODS

A chart review was performed to identify patients undergoing fornix reconstruction with cryopreserved ultra-thick human amniotic membrane for management of anophthalmic socket contracture. Patient demographics, disease etiology, and data regarding postoperative prosthesis fit and complications were collected.

RESULTS

The technique is described in 3 female patients with anophthalmic socket contracture who underwent fornix reconstruction using cryopreserved ultra-thick human amniotic membrane. All patients had excellent prosthesis fit at final follow up (range, 10-14 months). There were no clinically significant complications and no reoperations were performed. One pyogenic granuloma developed and was excised without affecting ocular prosthesis fit.

CONCLUSIONS

Cryopreserved ultra-thick human amniotic membrane is easy to use, well tolerated, and produces good outcomes for management of anophthalmic socket contracture.

The Use of Umbilical Amnion for Conjunctival Socket, Fornix, and Eyelid Margin Reconstruction

PURPOSE

To describe outcomes using umbilical amnion for conjunctival fornix, socket, and eyelid margin reconstruction.

METHODS

A medical record review was performed to identify patients who had received umbilical amnion over a 2-year period in their department. Patient demographics, disease etiology, and data regarding surgical outcomes were collected. The primary outcome was the success rate of the surgical intervention.

RESULTS

Twenty-one patients received umbilical amnion for anophthalmic socket contracture (n = 16), orbital implant exposure (n = 3), ocular surface burn (n = 1), and cicatricial entropion repair (n = 1). The primary outcome was met in 76% of patients overall. In anophthalmic socket contracture, the primary outcome was met in 86% and 0% of patients with acquired and congenital anophthalmia, respectively. The primary outcome was met in all cases of orbital implant exposure and cicatricial entropion. The primary outcome was not met in a Roper-Hall grade IV ocular surface burn.

CONCLUSIONS

Umbilical amnion is an ideal substrate graft for reconstruction of the conjunctival fornix, socket, and eyelid margin. Umbilical amnion appears to be efficacious for the management of socket contracture in acquired anophthalmia, orbital implant exposure, and cicatricial entropion. Further experience is needed to determine the efficacy of umbilical amnion in ocular surface burns.

Reparative and Regenerative Effects of Mesenchymal Stromal Cells-Promising Potential for Kidney Transplantation?

Mesenchymal stromal cells (MSCs) possess reparative, regenerative and immunomodulatory properties. The current literature suggests that MSCs could improve kidney transplant outcome via immunomodulation. In many clinical domains, research has also focussed on the regenerative and reparative effects of therapies with MSCs. However, in the field of transplantation, data on this subject remain scarce. This review provides an overview of what is known about the regenerative and reparative effects of MSCs in various fields ranging from wound care to fracture healing and also examines the potential of these promising MSC properties to improve the outcome of kidney transplantations.

Characterization of Human Mesenchymal Stem Cells from Different Tissues and Their Membrane Encasement for Prospective Transplantation Therapies

Human mesenchymal stem cells can be isolated from various organs and are in studies on therapeutic cell transplantation. Positive clinical outcomes of transplantations have been attributed to both the secretion of cytokines and growth factors as well as the fusion of donor cells with that of the host. We compared human mesenchymal stem cells from six different tissues for their transplantation-relevant potential. Furthermore, for prospective allogenic transplantation we developed a semipermeable hollow-fiber membrane enclosure, which would prevent cell fusion, would provide an immune barrier, and would allow for easy removal of donor cells from patients after recovery. We investigated human mesenchymal stem cells from adipose tissue, amniotic tissue, bone marrow, chorionic tissue, liver, and umbilical cord. We compared their multilineage differentiation potential, secretion of growth factors, and the expression of genes and surface markers. We found that although the expression of typical mesenchymal stem cell-associated gene THY1 and surface markers CD90 and CD73 were mostly similar between mesenchymal stem cells from different donor sites, their expression of lineage-specific genes, secretion of growth factors, multilineage differentiation potential, and other surface markers were considerably different. The encasement of mesenchymal stem cells in fibers affected the various mesenchymal stem cells differently depending on their donor site. Conclusively, mesenchymal stem cells isolated from different tissues were not equal, which should be taken into consideration when deciding for optimal sourcing for therapeutic transplantation. The encasement of mesenchymal stem cells into semipermeable membranes could provide a physical immune barrier, preventing cell fusion.

Equine Cord Blood Mesenchymal Stromal Cells Have Greater Differentiation and Similar Immunosuppressive Potential to Cord Tissue Mesenchymal Stromal Cells

Mesenchymal stromal cells (MSCs) are the most common cell population studied for therapeutic use in veterinary medicine. MSCs obtained from neonatal sources such as umbilical cord tissue (CT-MSCs) or cord blood (CB-MSCs) are appealing due to the non-invasive nature of procurement and the time allowed for characterization of cells before use. However, it remains unclear as to whether CB- or CT-MSCs have equivalent progenitor and non-progenitor functions. CB-MSCs have been shown to have superior chondrogenic potential to MSCs from other sources, whereas their immunomodulatory capacity does not seem to vary significantly. Using equine CB-MSCs and CT-MSCs from the same donors, we hypothesized that MSCs from both sources would have a similar immunophenotype, that CB-MSCs would be more amenable to differentiation, and that they can equally suppress lymphocyte proliferation. We evaluated cells from both sources for "classic" equine MSC markers CD90, CD105, CD29, and CD44, as well as pericyte markers CD146, NG2, and α-SMA. Contrary to our hypothesis, CB-MSCs showed mid- to high expression of pericyte surface markers CD146 and NG2, whereas expression in CT-MSCs was absent. On trilineage differentiation, CB-MSCs were more osteogenic and chondrogenic based on alkaline phosphatase activity and glycosaminoglycan content, respectively. Finally, using a mononuclear cell (MNC) suppression assay, we determined that both CB-MSCs and CT-MSCs are capable of suppressing stimulated MNC proliferation to a similar degree. We have determined that the choice of MSC tissue source should be made with the intended application in mind. This appears to be particularly relevant if pursuing a progenitor-based treatment strategy.

Wharton's Jelly Derived Mesenchymal Stem Cells: Comparing Human and Horse

Wharton's jelly (WJ) is an important source of mesenchymal stem cells (MSCs) both in human and other animals. The aim of this study was to compare human and equine WJMSCs. Human and equine WJMSCs were isolated and cultured using the same protocols and culture media. Cells were characterized by analysing morphology, growth rate, migration and adhesion capability, immunophenotype, differentiation potential and ultrastructure. Results showed that human and equine WJMSCs have similar ultrastructural details connected with intense synthetic and metabolic activity, but differ in growth, migration, adhesion capability and differentiation potential. In fact, at the scratch assay and transwell migration assay, the migration ability of human WJMSCs was higher (P < 0.05) than that of equine cells, while the volume of spheroids obtained after 48 h of culture in hanging drop was larger than the volume of equine ones (P < 0.05), demonstrating a lower cell adhesion ability. This can also revealed in the lower doubling time of equine cells (3.5 ± 2.4 days) as compared to human (6.5 ± 4.3 days) (P < 0.05), and subsequently in the higher number of cell doubling after 44 days of culture observed for the equine (20.3 ± 1.7) as compared to human cells (8.7 ± 2.4) (P < 0.05), and to the higher (P < 0.05) ability to form fibroblast colonies at P3. Even if in both species tri-lineage differentiation was achieved, equine cells showed an higher chondrogenic and osteogenic differentiation ability (P < 0.05). Our findings indicate that, although the ultrastructure demonstrated a staminal phenotype in human and equine WJMSCs, they showed different properties reflecting the different sources of MSCs.

Evaluation of Placental Mesenchymal Stem Cell Sheets for Myocardial Repair and Regeneration

IMPACT STATEMENT

This work explores placental tissue as a cell source for fabrication of tissue-engineered surgical patches for myocardial repair of congenital heart defects. This study demonstrates promising findings for the clinically driven evaluation of the cell source as defined by potential cardiac benefit, compatibility, cell source availability, and implant deliverability. It documents methods for the isolation of mesenchymal stem cells from human placental amnion and chorion tissues, characterization of these cells, and eventual cell sheet growth that can be leveraged going forward for patch fabrication. It establishes support to continue pursuing the placenta as a valuable cell source for myocardial repair.

A randomized, controlled study to evaluate the efficacy of intra-articular, autologous adipose tissue injections for the treatment of mild-to-moderate knee osteoarthritis compared to hyaluronic acid: a study protocol

BACKGROUND

Osteoarthritis (OA) is a highly debilitating joint disease that causes progressive, irreversible damage to articular cartilage. OA takes a massive toll on society that has grown in recent decades, but no therapy has been shown to halt or reverse the progression of the disease. The critical need for better treatments and increased interest cellular therapies has spawned a new generation of "minimally manipulated" cell treatments. Autologous adipose tissue injections are among the most controversial of these new treatments. Despite a lack of clinical evidence, adipose tissue injections are often marketed as "stem cell" injections with wide-ranging regenerative benefits. The purpose of this study is to estimate the effect size of the treatment by comparing the efficacy of autologous fat to hyaluronic acid (HA). As a secondary aim, we will test for preliminary evidence of efficacy of autologous fat vs. HA.

METHODS

This is a prospective, single-center, parallel-group, randomized, controlled trial. Participants (n = 54) will receive either a single intra-articular, ultrasound-guided injection of autologous adipose tissue or a single intra-articular, ultrasound-guided injection of HA (1:1 ratio). Outcome data will be obtained at baseline, week-6 and month-6. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain domain (WOMAC-A) will be used as the primary outcome measure. Secondary clinical outcome measures include WOMAC (full), clinical anchors (pain, function, and stiffness), and the 29-point Patient-Reported Outcomes Measurement Information System (PROMIS®) profile. We will also take synovial fluid samples and assess sway velocity using a force plate, as well as analyze excess/discard adipose tissue to gain a better understanding of how intra-articular adipose tissue injections influence the biochemical environment of the joint.

DISCUSSION

Given the widespread use of intra-articular fat injections in the United States, it is critical that randomized, controlled human studies evaluating efficacy and biological activity be performed. This study is the first step in addressing this unmet need, but it is not without limitations. The most notable limitations of this study are its small size and lack of blinding, which predisposes the study to both investigator and participant bias.

TRIAL REGISTRATION

NCT03242707 // HS-17-00365 // Registration Date (First Posted): August 8, 2018.

Towards biobanking technologies for natural and bioengineered multicellular placental constructs

Clinical application of a large variety of biomaterials is limited by the imperfections in storage technology. Perspective approaches utilizing low-temperature storage are especially challenging for multicellular structures, such as tissues, organs, and bioengineered constructs. Placenta, as a temporary organ, is a widely available unique biological material, being among the most promising sources of various cells and tissues for clinical and experimental use in regenerative medicine and tissue engineering. The aim of this study was to analyse the mechanisms of cryoinjuries in different placental tissues and bioengineered constructs as well as to support the viability after low temperature storage, which would contribute to development of efficient biobanking technologies. This study shows that specificity of cryodamage depends on the structure of the studied object, intercellular bonds, as well as interaction of its components with cryoprotective agents. Remarkably, it was possible to efficiently isolate cells after thawing from all of the studied tissues. While the outcome was lower in comparison to the native non-frozen samples, the phenotype and expression levels of pluripotency genes remained unaffected. Further progress in eliminating of recrystallization processes during thawing would significantly improve biobanking technologies for multicellular constructs and tissues.

Characterization of Human Mesenchymal Stem Cells Isolated from the Testis

Mesenchymal stem cells hold great promise for regenerative medicine as they can be easily isolated from different sources such as adipose tissue, bone marrow, and umbilical cord blood. Spontaneously arising pluripotent stem cells can be obtained in culture from murine spermatogonial stem cells (SSCs), while the pluripotency of the human counterpart remains a matter of debate. Recent gene expression profiling studies have demonstrated that embryonic stem cell- (ESC-) like cells obtained from the human testis are indeed closer to mesenchymal stem cells (MSCs) than to pluripotent stem cells. Here, we confirm that colonies derived from human testicular cultures, with our isolation protocol, are of mesenchymal origin and do not arise from spermatogonial stem cells (SSCs). The testis, thus, provides an important and accessible source of MSCs (tMSCs) that can be potentially used for nephrotoxicity testing in vitro. We further demonstrate, for the first time, that tMSCs are able to secrete microvesicles that could possibly be applied to the treatment of various chronic diseases, such as those affecting the kidney.

The Science and Clinical Applications of Placental Tissues in Spine Surgery

STUDY DESIGN

Narrative literature review.

OBJECTIVES

Placental tissue, amniotic/chorionic membrane, and umbilical cord have seen a recent expansion in their clinical application in various fields of surgery. It is important for practicing surgeons to know the underlying science, especially as it relates to spine surgery, to understand the rationale and clinical indication, if any, for their usage.

METHODS

A literature search was performed using PubMed and MEDLINE databases to identify studies reporting the application of placental tissues as it relates to the practicing spine surgeon. Four areas of interest were identified and a comprehensive review was performed of available literature.

RESULTS

Clinical application of placental tissue holds promise with regard to treatment of intervertebral disc pathology, preventing epidural fibrosis, spinal dysraphism closure, and spinal cord injury; however, there is an overall paucity of high-quality evidence. As such, evidence-based guidelines for its clinical application are currently unavailable.

CONCLUSIONS

There is no high-level clinical evidence to support the application of placental tissue for spinal surgery, although it does hold promise for several areas of interest for the practicing spine surgeon. High-quality research is needed to define the clinical effectiveness and indications of placental tissue as it relates to spine surgery.

Incorporating placental tissue in cord blood banking for stem cell transplantation

INTRODUCTION

Human term placenta is comprised of various tissues from which different cells can be obtained, including hematopoietic stem cells and mesenchymal stem/stromal cells (MSCs). Areas covered: This review will discuss the possibility to incorporate placental tissue cells in cord blood banking. It will discuss general features of human placenta, with a brief review of the immune cells at the fetal-maternal interface and the different cell populations isolated from placenta, with a particular focus on MSCs. It will address the question as to why placenta-derived MSCs should be banked with their hematopoietic counterparts. It will discuss clinical trials which are studying safety and efficacy of placenta tissue-derived MSCs in selected diseases, and preclinical studies which have proven their therapeutic properties in other diseases. It will discuss banking of umbilical cord blood and raise several issues for improvement, and the applications of cord blood cells in non-malignant disorders. Expert commentary: Umbilical cord blood banking saves lives worldwide. The concomitant banking of non-hematopoietic cells from placenta, which could be applied therapeutically in the future, alone or in combination to their hematopoietic counterparts, could exploit current banking processes while laying the foundation for clinical trials exploring placenta-derived cell therapies in regenerative medicine.

Stem Cell Considerations for the Clinician

"Although there is ample evidence that beneficial results can be obtained from the use of mesenchymal stem cells, several questions regarding their use remain to be answered. For many of these questions, preclinical models will be helpful, but the task of evaluating and implementing these findings for orthopaedic patients falls onto the shoulders of clinical researchers. Evaluation of these questions is a daunting, but such a challenge fits the concept of personalized medicine in today's medicine."

Mesenchymal Stem Cell Levels of Human Spinal Tissues

STUDY DESIGN

Systematic review.

OBJECTIVE

The aim of this study was to investigate, quantify, compare, and compile the various mesenchymal stem cell (MSC) tissue sources within human spinal tissues to act as a compendium for clinical and research application.

SUMMARY OF BACKGROUND DATA

Recent years have seen a dramatic increase in academic and clinical understanding of human MSCs. Previously limited to cells isolated from bone marrow, the past decade has illicited the characterization and isolation of human MSCs from adipose, bone marrow, synovium, muscle, periosteum, peripheral blood, umbilical cord, placenta, and numerous other tissues. As researchers explore practical applications of cells in these tissues, the absolute levels of MSCs in specific spinal tissue will be critical to guide future research.

METHODS

The PubMED, MEDLINE, EMBASE, and Cochrane databases were searched for articles relating to the harvest, characterization, isolation, and quantification of human MSCs from spinal tissues. Selected articles were examined for relevant data, categorized according to type of spinal tissue, and when possible, standardized to facilitate comparisons between sites.

RESULTS

Human MSC levels varied widely between spinal tissues. Yields for intervertebral disc demonstrated roughly 5% of viable cells to be positive for MSC surface markers. Cartilage endplate cells yielded 18,500 to 61,875 cells/0.8 mm thick sample of cartilage end plate. Ligamentum flavum yielded 250,000 to 500,000 cells/g of tissue. Annulus fibrosus fluorescence activated cell sorting treatment found 29% of cells positive for MSC marker Stro-1. Nucleus pulposus yielded mean tissue samples of 40,584 to 234,137 MSCs per gram of tissue.

CONCLUSION

Numerous tissues within and surrounding the spine represent a consistent and reliable source for the harvest and isolation of human MSCs. Among the tissues of the spine, the annulus fibrosus and ligamentum flavum each offer considerable levels of MSCs, and may prove comparable to that of bone marrow.

LEVEL OF EVIDENCE

5.

Recent Advances in Tissue Engineering Strategies for the Treatment of Joint Damage

PURPOSE OF REVIEW

While the clinical potential of tissue engineering for treating joint damage has yet to be realized, research and commercialization efforts in the field are geared towards overcoming major obstacles to clinical translation, as well as towards achieving engineered grafts that recapitulate the unique structures, function, and physiology of the joint. In this review, we describe recent advances in technologies aimed at obtaining biomaterials, stem cells, and bioreactors that will enable the development of effective tissue-engineered treatments for repairing joint damage.

RECENT FINDINGS

3D printing of scaffolds is aimed at improving the mechanical structure and microenvironment necessary for bone regeneration within a damaged joint. Advances in our understanding of stem cell biology and cell manufacturing processes are informing translational strategies for the therapeutic use of allogeneic and autologous cells. Finally, bioreactors used in combination with cells and biomaterials are promising strategies for generating large tissue grafts for repairing damaged tissues in pre-clinical models. Together, these advances along with ongoing research directions are making tissue engineering increasingly viable for the treatment of joint damage.

Comparison of Immunological Characteristics of Mesenchymal Stem Cells from the Periodontal Ligament, Umbilical Cord, and Adipose Tissue

Mesenchymal stem cells (MSCs) are of therapeutic importance in the fields of regenerative medicine and immunological diseases. Accordingly, studies evaluating MSCs for clinical applications are increasing. In this study, we characterized MSCs from the periodontal ligament, umbilical cord (UC-MSCs), and adipose tissue, which were relatively easy to obtain with limited ethical concerns regarding their acquisition, and compared their immunological characteristics. Among MSCs isolated from the three different tissues, UC-MSCs grew the fastest in vitro. The three types of MSCs were shown to inhibit proliferation of activated peripheral blood mononuclear cells (PBMCs) to a similar degree, via the indoleamine 2,3-dioxygenase and cyclooxygenase-2 pathways. They were also shown to inhibit the proliferation of PBMCs using HLA-G, which was most prominent in UC-MSCs. Unlike the other two types of MSCs, UC-MSCs showed minimal expression of HLA-DR after activation, suggesting that they pose minimal risk of initiating an allogeneic immune response when administered in vivo. These characteristics, the ease of collection, and the minimal ethical concerns regarding their use suggest UC-MSCs to be suitable MSC therapeutic candidates.

The Placenta: Applications in Orthopaedic Sports Medicine

BACKGROUND

Placenta has a long history of use for treating burns and wounds. It is a rich source of collagen and other extracellular matrix proteins, tissue reparative growth factors, and stem cells, including mesenchymal stem cells (MSCs). Recent data show its therapeutic potential for orthopaedic sports medicine indications.

PURPOSE

To provide orthopaedic surgeons with an anatomic description of the placenta, to characterize its cellular composition, and to review the literature reporting the use of placenta-derived cells and placental tissue allografts for orthopaedic sports medicine indications in animal models and in humans.

STUDY DESIGN

Systematic review.

METHODS

Using a total of 63 keyword combinations, the PubMed and MEDLINE databases were searched for published articles describing the use of placental cells and/or tissue for orthopaedic sports medicine indications. Information was collected on placental tissue type, indications, animal model, study design, treatment regimen, safety, and efficacy outcomes. Results were categorized by indication and subcategorized by animal model.

RESULTS

Outcomes for 29 animal studies and 6 human studies reporting the use of placenta-derived therapeutics were generally positive; however, the placental tissue source, clinical indication, and administration route were highly variable across these studies. Fourteen animal studies described the use of placental tissue for tendon injuries, 13 studies for osteoarthritis or articular cartilage injuries, 3 for ligament injuries, and 1 for synovitis. Both placenta-derived culture-expanded cells (epithelial cells or MSCs) and placental tissue allografts were used in animal studies. In all human studies, commercial placental allografts were used. Five of 6 human studies examined the treatment of foot and ankle pathological conditions, and 1 studied the treatment of knee osteoarthritis.

CONCLUSION

A review of the small number of reported studies revealed a high degree of variability in placental cell types, placental tissue preparation, routes of administration, and treatment regimens, which prohibits making any definitive conclusions. Currently, the clinical use of placenta is limited to only commercial placental tissue allografts, as there are no placenta-derived biological drugs approved for the treatment of orthopaedic sports medicine conditions in the United States. However, this review shows that the application of placental cells or tissue allografts appears to be safe and has potential to improve outcomes for orthopaedic sports medicine indications.

Therapeutic potential of mesenchymal stem cells for diabetes

Mesenchymal stem cells (MSCs) are self-renewing multipotent cells that have the capacity to secrete multiple biologic factors that can restore and repair injured tissues. Preclinical and clinical evidence have substantiated the therapeutic benefit of MSCs in various medical conditions. Currently, MSCs are the most commonly used cell-based therapy in clinical trials because of their regenerative effects, ease of isolation and low immunogenicity. Experimental and clinical studies have provided promising results using MSCs to treat diabetes. This review will summarize the role of MSCs on tissue repair, provide emerging strategies to improve MSC function and describe how these processes translate to clinical treatments for diabetes.

Human Umbilical Cord Blood Cell Transplantation in Neuroregenerative Strategies

At present there is no effective treatment of pathologies associated with the death of neurons and glial cells which take place as a result of physical trauma or ischemic lesions of the nervous system. Thus, researchers have high hopes for a treatment based on the use of stem cells (SC), which are potentially able to replace dead cells and synthesize neurotrophic factors and other molecules that stimulate neuroregeneration. We are often faced with ethical issues when selecting a source of SC. In addition to precluding these, human umbilical cord blood (hUCB) presents a number of advantages when compared with other sources of SC. In this review, we consider the key characteristics of hUCB, the results of various studies focused on the treatment of neurodegenerative diseases (Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis), ischemic (stroke) and traumatic injuries of the nervous system and the molecular mechanisms of hUCB-derived mononuclear and stem cells.

Clinical-grade human umbilical cord-derived mesenchymal stem cells reverse cognitive aging via improving synaptic plasticity and endogenous neurogenesis

Cognitive aging is a leading public health concern with the increasing aging population, but there is still lack of specific interventions directed against it. Recent studies have shown that cognitive function is intimately affected by systemic milieu in aging brain, and improvement of systemic environment in aging brain may be a promising approach for rejuvenating cognitive aging. Here, we sought to study the intervention effects of clinical-grade human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) on cognitive aging in a murine model of aging. The conventional aging model in mice induced by d-galactose (d-gal) was employed here. Mice received once every two weeks intraperitoneal administration of hUC-MSCs. After 3 months of systematical regulation of hUC-MSCs, the hippocampal-dependent learning and memory ability was effectively improved in aged mice, and the synaptic plasticity was remarkably enhanced in CA1 area of the aged hippocampus; moreover, the neurobiological substrates that could impact on the function of hippocampal circuits were recovered in the aged hippocampus reflecting in: dendritic spine density enhanced, neural sheath and cytoskeleton restored, and postsynaptic density area increased. In addition, the activation of the endogenic neurogenesis which is beneficial to stabilize the neural network in hippocampus was observed after hUC-MSCs transplantation. Furthermore, we demonstrated that beneficial effects of systematical regulation of hUC-MSCs could be mediated by activation of mitogen-activated protein kinase (MAPK)-ERK-CREB signaling pathway in the aged hippocampus. Our study provides the first evidence that hUC-MSCs, which have the capacity of systematically regulating the aging brain, may be a potential intervention for cognitive aging.