Yield of human adipose-derived adult stem cells from liposuction aspirates

Long-Term Effects of Adipose-Derived Stem Cells for the Treatment of Bilateral Limbal Stem Cell Deficiency

PURPOSE

To determine the safety and feasibility of human autologous adipose tissue-derived adult mesenchymal stem cells (ASCs) for ocular surface regeneration in patients with bilateral limbal stem-cell deficiency (LSCD).

METHODS

A phase IIa clinical trial was designed (https://Clinicaltrials.gov, NCT01808378) with 8 patients, 3 of whom had aniridia, 2 meibomian glands diseases, 2 multiple surgeries and 1 chronic chemical injury. The therapeutic protocol was as follows: 6-mm of central corneal epithelium was removed, 400,000 ASCs were injected into each limboconjunctival quadrant, 400,000 ASCs were suspended over the cornea for 20 min, and finally the cornea was covered with an amniotic membrane patch.

RESULTS

No adverse events were detected after a mean of 86,5 months of follow-up. One year after surgery, 6 of the 8 transplants were scored as successful, five patients had improved uncorrected visual acuity (mean of 12 letters), two patients presented epithelial defects (also present at baseline) and the mean percentage of corneal neovascularization was of 28.75% (36.98%, at baseline). Re-examination 24 months after treatment disclosed preserved efficacy in 4 patients. At the last visit (after a mean of 86,5 months of follow up) epithelial defects were absent in all patients although improvement in all of the variables was only maintained in patient 3 (meibomian glands agenesia).

CONCLUSION

ASCs are a feasible and conservative therapy for treating bilateral LSCD. The therapeutic effect differs between etiologies and diminishes over time.

A Simple and Effective Mechanical Method for Adipose-Derived Stromal Vascular Fraction Isolation

Over the last decades, there has been ongoing and evolving research concerning regenerative medicine, specifically, stem cells. The most common source of adult mesenchymal stem cells (MSCs) remains the adipose tissue and the easiest way to obtain such tissue is lipoaspirate. The fatty tissue obtained can be processed either in an enzymatic way, which is time-consuming and expensive and carries several dangers for the viability of the stem cells included, or with mechanical means which are fast, inexpensive, yield enough viable cells, and can be readily used for autologous transplantation in one-stage procedures. Herein, we demonstrate our non-enzymatic method for obtaining adipose-derived stromal vascular fraction comprising MSCs. The stromal vascular fraction was isolated via centrifugation, and the characteristics and numbers of the cells isolated have been tested with flow cytometry assay, cell culture, and differentiation. Over 91% of viable MSCs were isolated using the mechanical method. The cells retained the ability to differentiate into osteocytes, adipocytes, and chondrocytes. The method presented is simple, requiring no special equipment, and yields a viable population of stem cells in large numbers. These cells can be readily used in several operations (orthopedic, dentistry, fistulas, etc.) making feasible "one-stage" procedures, thus proving their benefits for the patient and the health care system.

Adult Stem Cells Freezing Processes and Cryopreservation Protocols

The development of simple but effective storage protocols for adult stem cells will greatly enhance their use and utility in tissue-engineering applications. Cryopreservation has shown the most promise but is a fairly complex process, necessitating the use of chemicals called cryoprotective agents (CPAs), freezing equipment, and obviously, storage in liquid nitrogen. The purpose of this chapter is to present a general overview of cryopreservation storage techniques and the optimal protocols/results obtained in our laboratory for long-term storage of adult stem cells using freezing storage.

Synthesis and characterization of a silk fibroin/placenta matrix hydrogel for breast reconstruction

Reconstructive surgery is a complex and demanding interdisciplinary field. One of the major challenges is the production of sizeable, implantable, inexpensive bioprostheses such as breast implants. In this study, porous hybrid hydrogels were fabricated by a combinatorial method using decellularized human placenta (dHplacenta) and silk fibroin. Histology was used to confirm the acellularity of the dHplacenta. The physio-chemical properties of the hydrogels were evaluated using SEM, FTIR, and rheological assays. The synthesized hydrogels exhibited a uniform 3-D microstructure with an interconnected porous network, and the hybrid hydrogels with a 30/70 ratio had improved mechanical properties compared to the other hydrogels. Hybrid hydrogels were also cultured with adipose-derived mesenchymal stem cells (ADSCs). Liposuction was used to obtain adipose tissue from patients, which was then characterized using flow cytometry and karyotyping. The results showed that CD34 and CD31 were downregulated, whereas CD105 and CD90 were upregulated in ADSCs, indicating a phenotype resembling to that of mesenchymal stem cells from the human bone marrow. Moreover, after re-cellularized hydrogel, the live/dead assay and SEM analysis confirmed that most viability and cellular expansion on the hydrogels contained higher ratios of dHplacenta (30/70) than the other two groups. All these findings recapitulated that the 30/70 dHplacenta/silk fibroin hydrogel can perform as an excellent substrate for breast tissue engineering applications.

Management of partial-thickness rotator cuff tears with autologous adipose-derived regenerative cells is safe and more effective than injection of corticosteroid

Symptomatic, partial-thickness rotator cuff tears (sPTRCT) are problematic. This study tested the hypothesis that management of sPTRCT with injection of fresh, uncultured, unmodified, autologous, adipose-derived regenerative cells (UA-ADRCs) is safe and more effective than injection of corticosteroid even in the long run. To this end, subjects who had completed a former randomized controlled trial were enrolled in the present study. At baseline these subjects had not responded to physical therapy treatments for at least 6 weeks, and were randomly assigned to receive respectively a single injection of UA-ADRCs (n = 11) or a single injection of methylprednisolone (n = 5). Efficacy was assessed using the ASES Total score, pain visual analogue scale (VAS), RAND Short Form-36 Health Survey and range of motion at 33.2 ± 1.0 (mean ± SD) and 40.6 ± 1.9 months post-treatment. Proton density, fat-saturated, T2-weighted MRI of the index shoulder was performed at both study visits. There were no greater risks connected with injection of UA-ADRCs than those connected with injection of corticosteroid. The subjects in the UA-ADRCs group showed statistically significantly higher mean ASES Total scores than the subjects in the corticosteroid group. The MRI scans at 6 months post-treatment allowed to "watch the UA-ADRCs at work".

Low-glucose culture environment can enhance the wound healing capability of diabetic adipose-derived stem cells

BACKGROUND

Application of autologous adipose-derived stem cells (ASC) for diabetic chronic wounds has become an emerging treatment option. However, ASCs from diabetic individuals showed impaired cell function and suboptimal wound healing effects. We proposed that adopting a low-glucose level in the culture medium for diabetic ASCs may restore their pro-healing capabilities.

METHODS

ASCs from diabetic humans and mice were retrieved and cultured in high-glucose (HG, 4.5 g/L) or low-glucose (LG, 1.0 g/L) conditions. Cell characteristics and functions were investigated in vitro. Moreover, we applied diabetic murine ASCs cultured in HG or LG condition to a wound healing model in diabetic mice to compare their healing capabilities in vivo.

RESULTS

Human ASCs exhibited decreased cell proliferation and migration with enhanced senescence when cultured in HG condition in vitro. Similar findings were noted in ASCs derived from diabetic mice. The inferior cellular functions could be partially recovered when they were cultured in LG condition. In the animal study, wounds healed faster when treated with HG- or LG-cultured diabetic ASCs relative to the control group. Moreover, higher collagen density, more angiogenesis and cellular retention of applied ASCs were found in wound tissues treated with diabetic ASCs cultured in LG condition.

CONCLUSIONS

In line with the literature, our study showed that a diabetic milieu exerts an adverse effect on ASCs. Adopting LG culture condition is a simple and effective approach to enhance the wound healing capabilities of diabetic ASCs, which is valuable for the clinical application of autologous ASCs from diabetic patients.

Adipose Tissue-Derived Products May Present Inflammatory Properties That Affect Chondrocytes and Synoviocytes from Patients with Knee Osteoarthritis

Adipose tissue-derived cell-based injectable therapies have been demonstrated to have disease-modifying effects on joint tissues in preclinical studies on animal osteoarthritis (OA) models, but clinical results are heterogeneous and not always satisfactory. The aim of this study was to investigate the influence of adipose tissue properties on the therapeutic effects of the adipose-derived product in an in vitro OA setting. Micro-fragmented adipose tissue (MF-AT) samples were obtained from 21 OA patients (mean age 51.7 ± 11.8 years, mean BMI 25.7 ± 4.1 kg/m2). The analysis of the MF-AT supernatant was performed to analyze the release of inflammatory factors. The effects of MF-AT inflammatory factors were investigated on chondrocytes and synoviocytes gene expression levels. Patients' characteristics were analyzed to explore their influence on MF-AT inflammatory molecules and on the MF-AT effects on the gene expression of chondrocytes and synoviocytes. The study results demonstrated that adipose tissue-derived products may present inflammatory properties that influence the therapeutic potential for OA treatment, with products with a higher pro-inflammatory profile stimulating a higher expression of genes related to a more inflamed and catabolic phenotype. A higher pro-inflammatory cytokine pattern and a higher pro-inflammatory effect were found in adipose tissue-derived products obtained from OA patients with higher BMI.

Placenta-Derived Products Demonstrate Good Safety Profile and Overall Satisfactory Outcomes for Treating Knee Osteoarthritis: A Systematic Review of Clinical Evidence

PURPOSE

To summarize the available evidence regarding the clinical application of placenta-derived products to treat knee osteoarthritis (OA), underlining the differences existing among products, their preparation methods, and the clinical results reported so far.

METHODS

A research on PubMed, Cochrane, and Google Scholar databases was performed. The following inclusion criteria for relevant articles were used: (1) randomized controlled trials (RCTs), prospective and retrospective studies, on humans; (2) written in English; (3) published in indexed journals in the last 10 years (2011-2022); and (4) dealing with the use of placenta-derived products for the treatment of knee OA. Exclusion criteria were articles written in other languages; animals or in vitro trials; reviews; and trials analyzing other applications of placenta-derived products not related to knee OA.

RESULTS

In total, 16 studies were included in the present systematic review. Five studies investigated placenta-derived products as an augmentation during surgical procedures, whereas 11 studies were focused on the injective approach only. Of these, only 4 were RCTs and were all from the injective approach group. Potential risk of bias was carried out using Cochrane Risk of Bias 2 tool for RCTs and a modified Coleman approach for nonrandomized studies, revealing for both an overall insufficient quality. Clinical outcomes reveal excellent safety profile and notable efficacy, despite the different types of products used and different administration methods adopted.

CONCLUSIONS

Placental products showed a good safety profile and overall satisfactory outcomes for the treatment of knee OA.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II, III and IV studies.

Examining the Effects of In Vitro Co-Culture of Equine Adipose-Derived Mesenchymal Stem Cells With Tendon Proper and Peritenon Cells

Tendinopathies remain the leading contributor to career-ending injuries in horses because of the complexity of tendon repair. As such, cell-based therapies like injections of adipose-derived mesenchymal stem cells (ADMSCs, or MSCs) into injured tendons are becoming increasingly popular though their long-term efficacy on a molecular and wholistic level remains contentious. Thus, we co-cultured equine MSCs with intrinsic (tendon proper) and extrinsic (peritenon) tendon cell populations to examine interactions between these cells. Gene expression for common tenogenic, perivascular, and differentiation markers was quantified at 48 and 120 hours. Additionally, cellular metabolism of proliferation was examined every 24 hours for peritenon and tendon proper cells co-cultured with MSCs. MSCs co-cultured with tendon proper or peritenon cells had altered expression profiles demonstrating trend toward tenogenic phenotype with the exception of decreases in type I collagen (COL1A1). Peritenon cells co-cultured with MSCs had a trending and significant decrease in biglycan (BGN) and CSPG4 at 48 hours and 120 hours but overall significant increases in lysyl oxidase (LOX), mohawk (MKX), and scleraxis (SCX) within 48 hours. Tendon proper cells co-cultured with MSCs also exhibited increases in LOX and SCX at 48 hours. Furthermore, cell proliferation improved overall for tendon proper cells co-cultured with MSCs. The co-culture study results suggest that adipose-derived MSCs contribute beneficially to tenogenic stimulation of peritenon or tendon proper cells.

Regenerative methods in osteoarthritis

Osteoarthritis (OA) is the most common type of arthritis that can affect all joint structures. The primary goals of osteoarthritis treatment are to alleviate pain, reduce functional limitations, and improve quality of life. Despite its high prevalence, treatment options for osteoarthritis are limited, with most therapeutic approaches focusing on symptom management. Tissue engineering and regenerative strategies based on biomaterials, cells, and other bioactive molecules have emerged as viable options for osteoarthritis cartilage repair. Platelet-rich plasma (PRP) and mesenchymal stem cells (MSCs) are the most commonly used regenerative therapies today to protect, restore, or increase the function of damaged tissues. Despite promising results, there is conflicting evidence regarding the efficacy of regenerative therapies, and their efficacy remains unknown. The data suggest that more research and standardization are required for the use of these therapies in osteoarthritis. This article provides an overview of the application of MSCs and PRP applications.

An enzyme-free technique enables the isolation of a large number of adipose-derived stem cells at the bedside

Adipose tissue derived stromal cells (ADSCs) play a crucial role in research and applications of regenerative medicine because they can be rapidly isolated in high quantities. Nonetheless, their purity, pluripotency, differentiation capacity, and stem cell marker expression might vary greatly depending on technique and tools used for extraction and harvesting. There are two methods described in the literature for isolating regenerative cells from adipose tissue. The first technique is enzymatic digestion, which utilizes many enzymes to remove stem cells from the tissue they reside in. The second method involves separating the concentrated adipose tissue using non-enzymatic, mechanical separation methods. ADSCs are isolated from the stromal-vascular fraction (SVF) of processed lipoaspirate, which is the lipoaspirate's aqueous portion. The purpose of this work was to evaluate a unique device 'microlyzer' for generating SVF from adipose tissue using a mechanical technique that required minimal intervention. The Microlyzer was examined using tissue samples from ten different patients. The cells that were retrieved were characterized in terms of their cell survival, phenotype, proliferation capacity, and differentiation potential. The number of progenitor cells extracted only from the microlyzed tissue was in comparable amount to the number of progenitor cells acquired by the gold standard enzymatic approach. The cells that were collected from each group exhibit similar levels of viability as well as proliferation rates. In addition, the differentiation potentials of the cells derived from the microlyzed tissue were investigated, and it was discovered that cells isolated through microlyzer entered the differentiation pathways more quickly and displayed a greater level of marker gene expression than cells isolated by enzymatic methods. These findings suggest that microlyzer, particularly in regeneration investigations, will allow quick and high rate cell separation at the bedside.

Cementum protein 1 gene-modified adipose-derived mesenchymal stem cell sheets enhance periodontal regeneration in osteoporosis rat

BACKGROUND AND OBJECTIVES

Osteoporosis (OP) and periodontitis are both diseases with excessive bone resorption, and the number of patients who suffer from these diseases is expected to increase. OP has been identified as a risk factor that accelerates the pathological process of periodontitis. Achieving effective and safe periodontal regeneration in OP patients is a meaningful challenge. This study aimed to assess the efficacy and biosecurity of human cementum protein 1 (hCEMP1) gene-modified cell sheets for periodontal fenestration defect regeneration in an OP rat model.

MATERIALS AND METHODS

Rat adipose-derived mesenchymal stem cells (rADSCs) were isolated from Sprague-Dawley rats. After primary culture, rADSCs were subjected to cell surface analysis and multi-differentiation assay. And rADSCs were transduced with hCEMP1 by lentiviral vector, and hCEMP1 gene-modified cell sheets were generated. The expression of hCEMP1 was evaluated by reverse transcription polymerase chain reaction and immunocytochemistry staining, and transduced cell proliferation was evaluated by Cell Counting Kit-8. The hCEMP1 gene-modified cell sheet structure was detected by histological analysis and scanning electron microscopy. Osteogenic and cementogenic-associated gene expression was evaluated by real-time quantitative polymerase chain reaction. In addition, an OP rat periodontal fenestration defect model was used to evaluate the regeneration effect of hCEMP1 gene-modified rADSC sheets. The efficacy was assessed with microcomputed tomography and histology, and the biosecurity of gene-modified cell sheets was evaluated by histological analysis of the spleen, liver, kidney and lung.

RESULTS

The rADSCs showed a phenotype of mesenchymal stem cells and possessed multi-differentiation capacity. The gene and protein expression of hCEMP1 through lentiviral transduction was confirmed, and there was no significant effect on rADSC proliferation. Overexpression of hCEMP1 upregulated osteogenic and cementogenic-related genes such as runt-related transcription factor 2, bone morphogenetic protein 2, secreted phosphoprotein 1 and cementum attachment protein in the gene-modified cell sheets. The fenestration lesions in OP rats treated with hCEMP1 gene-modified cell sheets exhibited complete bone bridging, cementum and periodontal ligament formation. Furthermore, histological sections of the spleen, liver, kidney and lung showed no evident pathological damage.

CONCLUSION

This pilot study demonstrates that hCEMP1 gene-modified rADSC sheets have a marked ability to enhance periodontal regeneration in OP rats. Thus, this approach may represent an effective and safe strategy for periodontal disease patients with OP.

Mesenchymal Stem Cells in Nerve Tissue Engineering: Bridging Nerve Gap Injuries in Large Animals

Cell-therapy-based nerve repair strategies hold great promise. In the field, there is an extensive amount of evidence for better regenerative outcomes when using tissue-engineered nerve grafts for bridging severe gap injuries. Although a massive number of studies have been performed using rodents, only a limited number involving nerve injury models of large animals were reported. Nerve injury models mirroring the human nerve size and injury complexity are crucial to direct the further clinical development of advanced therapeutic interventions. Thus, there is a great need for the advancement of research using large animals, which will closely reflect human nerve repair outcomes. Within this context, this review highlights various stem cell-based nerve repair strategies involving large animal models such as pigs, rabbits, dogs, and monkeys, with an emphasis on the limitations and strengths of therapeutic strategy and outcome measurements. Finally, future directions in the field of nerve repair are discussed. Thus, the present review provides valuable knowledge, as well as the current state of information and insights into nerve repair strategies using cell therapies in large animals.

Cartilage lesion size and number of stromal vascular fraction (SVF) cells strongly influenced the SVF implantation outcomes in patients with knee osteoarthritis

PURPOSE

This study evaluated outcomes in patients with knee osteoarthritis following stromal vascular fraction implantation and assessed the associated prognostic factors.

METHODS

We retrospectively evaluated 43 patients who underwent follow-up magnetic resonance imaging 12 months after stromal vascular fraction implantation for knee osteoarthritis. Pain was assessed using the visual analogue scale and measured at baseline and 1-, 3-, 6-, and 12-month follow-up appointments. In addition, cartilage repair was evaluated based on the Magnetic Resonance Observation of Cartilage Repair Tissue scoring system using the magnetic resonance imaging from the 12-month follow-up. Finally, we evaluated the effects of various factors on outcomes following stromal vascular fraction implantation.

RESULTS

Compared to the baseline value, the mean visual analogue scale score significantly and progressively decreased until 12 months post-treatment (P < 0.05 for all, except n.s. between the 1 and 3-month follow-ups). The mean Magnetic Resonance Observation of Cartilage Repair Tissue score was 70.5 ± 11.1. Furthermore, the mean visual analogue scale and Magnetic Resonance Observation of Cartilage Repair Tissue scores significantly correlated 12 months postoperatively (P = 0.002). Additionally, the cartilage lesion size and the number of stromal vascular fraction cells significantly correlated with the 12-month visual analogue scale scores and the Magnetic Resonance Observation of Cartilage Repair Tissue score. Multivariate analyses determined that the cartilage lesion size and the number of stromal vascular fraction cells had a high prognostic significance for unsatisfactory outcomes.

CONCLUSION

Stromal vascular fraction implantation improved pain and cartilage regeneration for patients with knee osteoarthritis. The cartilage lesion size and the number of stromal vascular fraction cells significantly influenced the postoperative outcomes. Thus, these findings may serve as a basis for preoperative surgical decisions.

LEVEL OF EVIDENCE

IV.

Hopes and opportunities of stem cells from human exfoliated deciduous teeth (SHED) in cartilage tissue regeneration

Cartilage lesions are common conditions, affecting elderly and non-athletic populations. Despite recent advances, cartilage regeneration remains a major challenge today. The absence of an inflammatory response following damage and the inability of stem cells to penetrate into the healing site due to the absence of blood and lymph vessels are assumed to hinder joint repair. Stem cell-based regeneration and tissue engineering have opened new horizons for treatment. With advances in biological sciences, especially stem cell research, the function of various growth factors in the regulation of cell proliferation and differentiation has been established. Mesenchymal stem cells (MSCs) isolated from different tissues have been shown to increase into therapeutically relevant cell numbers and differentiate into mature chondrocytes. As MSCs can differentiate and become engrafted inside the host, they are considered suitable candidates for cartilage regeneration. Stem cells from human exfoliated deciduous teeth (SHED) provide a novel and non-invasive source of MSCs. Due to their simple isolation, chondrogenic differentiation potential, and minimal immunogenicity, they can be an interesting option for cartilage regeneration. Recent studies have reported that SHED-derived secretome contains biomolecules and compounds that efficiently promote regeneration in damaged tissues, including cartilage. Overall, this review highlighted the advances and challenges of cartilage regeneration using stem cell-based therapies by focusing on SHED.

Advances in Mesenchymal Stem Cell Therapy for Osteoarthritis: From Preclinical and Clinical Perspectives

The prevalence of osteoarthritis (OA), a degenerative disorder of joints, has substantially increased in recent years. Its key pathogenic hallmarks include articular cartilage destruction, synovium inflammation, and bone remodeling. However, treatment outcomes are unsatisfactory. Until recently, common therapy methods, such as analgesic and anti-inflammatory treatments, were aimed to treat symptoms that cannot be radically cured. Mesenchymal stem cells (MSCs), i.e., mesoderm non-hematopoietic cells separated from bone marrow, adipose tissue, umbilical cord blood, etc., have been intensively explored as an emerging technique for the treatment of OA over the last few decades. According to existing research, MSCs may limit cartilage degradation in OA by interfering with cellular immunity and secreting a number of active chemicals. This study aimed to examine the potential mechanism of MSCs in the treatment of OA and conduct a thorough review of both preclinical and clinical data.

Therapeutic applications of adipose-derived stromal vascular fractions in osteoarthritis

Osteoarthritis (OA) is considered to be a highly heterogeneous disease with progressive cartilage loss, subchondral bone remodeling, and low-grade inflammation. It is one of the world's leading causes of disability. Most conventional clinical treatments for OA are palliative drugs, which cannot fundamentally cure this disease. The stromal vascular fraction (SVF) from adipose tissues is a heterogeneous cell population. According to previous studies, it contains a large number of mesenchymal stem cells, which have been used to treat OA with good therapeutic results. This safe, simple, and effective therapy is expected to be applied and promoted in the future. In this paper, the detailed pathogenesis, diagnosis, and current clinical treatments for OA are introduced. Then, clinical studies and the therapeutic mechanism of SVF for the treatment of OA are summarized.

Long non-coding RNA SNHG16 promotes human placenta-derived mesenchymal stem cell proliferation capacity through the PI3K/AKT pathway under hypoxia

BACKGROUND

The effect of hypoxia on mesenchymal stem cells (MSCs) is an emerging topic in MSC biology. Although long non-coding RNAs (lncRNAs) and messenger RNAs (mRNAs) are reported to play a critical role in regulating the biological characteristics of MSCs, their specific expression and co-expression profiles in human placenta-derived MSCs (hP-MSCs) under hypoxia and the underlying mechanisms of lncRNAs in hP-MSC biology are unknown.

AIM

To reveal the specific expression profiles of lncRNAs in hP-MSCs under hypoxia and initially explored the possible mechanism of lncRNAs on hP-MSC biology.

METHODS

Here, we used a multigas incubator (92.5% N₂, 5% CO₂, and 2.5% O₂) to mimic the hypoxia condition and observed that hypoxic culture significantly promoted the proliferation potential of hP-MSCs. RNA sequencing technology was applied to identify the exact expression profiles of lncRNAs and mRNAs under hypoxia.

RESULTS

We identified 289 differentially expressed lncRNAs and 240 differentially expressed mRNAs between the hypoxia and normoxia groups. Among them, the lncRNA SNHG16 was upregulated under hypoxia, which was also validated by reverse transcription-polymerase chain reaction. SNHG16 was confirmed to affect hP-MSC proliferation rates using a SNHG16 knockdown model. SNHG16 overexpression could significantly enhance the proliferation capacity of hP-MSCs, activate the PI3K/AKT pathway, and upregulate the expression of cell cycle-related proteins.

CONCLUSION

Our results revealed the specific expression characteristics of lncRNAs and mRNAs in hypoxia-cultured hP-MSCs and that lncRNA SNHG16 can promote hP-MSC proliferation through the PI3K/AKT pathway.

Adipose-Derived Stem Cells, Obesity, and Inflammation: A Systematic Review and Implications for Osteoarthritis Treatment

ABSTRACT

Adipose is a known source of mesenchymal stem cells that can be used to treat musculoskeletal disorders, such as osteoarthritis. Because obesity often coexists with osteoarthritis, excess adiposity may be a useful source of mesenchymal stem cells. However, obesity is associated with systemic inflammation, which may influence the quality of adipose-derived stem cells. We performed a systematic review of the literature examining adipose-derived stem cell behavior, cytokine, and growth factor profiles from obese and nonobese patients. Two independent reviewers applied the inclusion/exclusion criteria and independently extracted data including mesenchymal stem cell count/viability/behavior, growth factor, and/or cytokine expression. Twenty-two articles met criteria for inclusion. Samples from obese patients had increased mesenchymal stem cell content (n = 6), but decreased proliferative ability (n = 3), and increased expression of interleukin 1 (n = 3), interleukin 6 (n = 3), and tumor necrosis factor α (n = 6). There was also greater macrophage content (n = 4). Weight loss normalized cellular function. In vitro behavior and quality of adipose-derived stem cell are significantly different between obese and nonobese patients. Samples from obese patients had greater adipose-derived stem cell content, lower proliferative ability, increased senescence, and increased proinflammatory cytokine expression. Differences in cellular function should be considered when using adipose to treat musculoskeletal pathology in obese and nonobese patients.

Adipose-Derived Stem Cell Sheets Promote Meniscus Regeneration Regardless of Whether the Defect Involves the Inner Half or the Whole Width of the Anterior Half of the Medial Meniscus in a Rabbit Model

PURPOSE

To investigate the regenerative effect of adipose-derived stem cell (ADSC) sheets in two different rabbit models of meniscal defects.

METHODS

Forty-two rabbits were randomly divided into two groups: the whole (Group 1) or the inner half (Group 2) of anterior half of the medial meniscus was removed from both knees. The ADSC sheets were transplanted into one knee, whereas in the other knee the meniscal defect was left untreated (self-control). The histological score and expression of genes encoding collagen type I and II (COL1/2), SRY-box transcription factor 9 (SOX9), and aggrecan (ACAN) were compared between the ADSC sheet-treated and untreated menisci at 4 and 12 weeks. The ADSC sheet-treated menisci at 12 weeks were also analyzed immunohistochemically to assess the collagen component.

RESULTS

The histological score was significantly higher in the treated side than in the control side at 4 and 12 weeks in both groups (Group 1; P = .016 and .032; Group 2; P = .030 and .016, respectively). All genes evaluated showed significantly higher expression in the treated side than in the control side in both groups, except COL2 and SOX9 at 4 weeks and COL2 at 12 weeks in Group 1, and COL1 in Group 2 at 4 weeks. The ADSC sheet-treated meniscus in Group 1 contained mostly COL1, whereas the Group 2 had less COL1, but was rich in COL2.

CONCLUSIONS

ADSC sheets can promote meniscal regeneration regardless of whether the defect involves the inner half or whole width of the anterior half of the medial meniscus. However, the collagen component of the ADSC sheet-treated tissue differs depending on the defect site.

CLINICAL RELEVANCE

ADSCs may help meniscal regeneration due to meniscal defects after meniscectomy. This study suggests longer-term follow-up and mechanical analysis as next steps.

CXCR4+ Sorted Adipose-Derived Stem Cells Enhance Their Functional Benefits and Improve Cardiac Function after Myocardial Infarction

Objective

The homing of adipose-derived stem cells (ASCs) to infarcted myocardium, which is important for improved cardiac function, has been investigated previously, but with poor efficiency. Substantial improvements in engraftments are required to optimize ASC treatment. Stromal derived factor-1α (SDF-1α) is upregulated early after MI, and its endogenous receptor, chemokine receptor 4 (CXCR4), is pivotal in stem cell survival, migration, and engraftment. We examined whether CXCR4⁺ ASCs enhance their efficacy of migration and engraftment posttransplantation and improve heart function following myocardial infarction (MI).

Methods and Results

CXCR4⁺ ASC subpopulations were sorted by fluorescence-activated cell sorting. CXCR4⁺ sorted ASCs exhibited the stronger cell viability, the faster proliferation rate, and the better migration capability in comparison with unfractionated ASCs. CXCR4⁺ sorted ASCs secreted a higher level of angiogenic growth factors including VEGF, HGF, and IGF-1 relative to unfractionated ASCs. Fewer apoptotic cells under oxygen-glucose deprivation were detected in CXCR4⁺ sorted ASCs than in unfractionated ASCs. Osteogenic and angiogenic differentiation were more pronounced in CXCR4⁺ sorted ASCs than in unfractionated ASCs. At 3 days after acute MI, rats were randomly allocated to receive intramyocardial injection of cell culture medium, CXCR4⁺ sorted ASCs, and unfractionated ASCs. Left ventricular function was assessed echocardiographically 4 weeks thereafter. Explanted hearts were then processed for the immunofluorescence detection of survived cells, quantification of angiogenesis, and cell engraftment. CXCR4⁺ sorted ASCs more obviously engrafted into infarcted myocardium, more markedly inhibited collagen remodeling, and more effectively improved heart function and promoted capillary formation than did unfractionated ASCs.

Conclusion

CXCR4⁺ sorted ASCs are superior to unfractionated ASCs due to better viability, faster proliferation, more cytokine secretion, and stronger migration. CXCR4⁺ sorted ASCs provide better curative benefits on MI than do unfractionated ASCs and can be efficiently harvested and purified from adipose tissue, they may serve as a promising candidate for MI.

Specific features of ex-obese patients significantly influence the functional cell properties of adipose-derived stromal cells

Adipose-derived stromal cells (ADSC) are increasingly used in clinical applications due to their regenerative capabilities. However, ADSC therapies show variable results. This study analysed the effects of specific factors of ex-obese patients on ADSC functions. ADSC were harvested from abdominal tissues (N = 20) after massive weight loss. Patients were grouped according to age, sex, current and maximum body mass index (BMI), BMI difference, weight loss method, smoking and infection at the surgical site. ADSC surface markers, viability, migration, transmigration, sprouting, differentiation potential, cytokine secretion, telomere length and mtDNA copy number were analysed. All ADSC expressed CD73, CD90, CD105, while functional properties differed significantly among patients. A high BMI difference due to massive weight loss was negatively correlated with ADSC proliferation, migration and transmigration, while age, sex or weight loss method had a smaller effect. ADSC from female and younger donors and individuals after weight loss by increase of exercise and diet change had a higher activity. Telomere length, mtDNA copy number, differentiation potential and the secretome did not correlate with patient factors or cell function. Therefore, we suggest that factors such as age, sex, increase of exercise and especially weight loss should be considered for patient selection and planning of regenerative therapies.

Enhanced angiogenic potential of adipose-derived stem cell sheets by integration with cell spheroids of the same source

Background

Adipose-derived stem cell (ASC) has been considered as a desirable source for cell therapy. In contrast to combining scaffold materials with cells, ASCs can be fabricated into scaffold-free three-dimensional (3D) constructs to promote regeneration at tissue level. However, previous reports have found decreased expression of vascular endothelial growth factor (VEGF) in ASC sheets. In this study, we aimed to integrate ASC spheroids into ASC sheets to enhance the angiogenic capability of cell sheets.

Methods

ASCs were seeded in agarose microwells to generate uniform cell spheroids with adjustable size, while extracellular matrix deposition could be stimulated by ascorbic acid 2-phosphate to form ASC sheets. RNA sequencing was performed to identify the transcriptomic profiles of ASC spheroids and sheets relative to monolayer ASCs. By transferring ASC spheroids onto ASC sheets, the spheroid sheet composites could be successfully fabricated after a short-term co-culture, and their angiogenic potential was evaluated in vitro and in ovo.

Results

RNA sequencing analysis revealed that upregulation of angiogenesis-related genes was found only in ASC spheroids. The stimulating effect of spheroid formation on ASCs toward endothelial lineage was demonstrated by enhanced CD31 expression, which maintained after ASC spheroids were seeded on cell sheets. Relative to ASC sheets, enhanced expression of VEGF and hepatocyte growth factor was also noted in ASC spheroid sheets, and conditioned medium of ASC spheroid sheets significantly enhanced tube formation of endothelial cells in vitro. Moreover, chick embryo chorioallantoic membrane assay showed a significantly higher capillary density with more branch points after applying ASC spheroid sheets, and immunohistochemistry also revealed a significantly higher ratio of CD31-positive area.

Conclusion

In the spheroid sheet construct, ASC spheroids can augment the pro-angiogenesis capability of ASC sheets without the use of exogenous biomaterial or genetic manipulation. The strategy of this composite system holds promise as an advance in 3D culture technique of ASCs for future application in angiogenesis and regeneration therapies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-02948-3.

Optimization of Mesenchymal Stromal Cell (MSC) Manufacturing Processes for a Better Therapeutic Outcome

MSCs products as well as their derived extracellular vesicles, are currently being explored as advanced biologics in cell-based therapies with high expectations for their clinical use in the next few years. In recent years, various strategies designed for improving the therapeutic potential of mesenchymal stromal cells (MSCs), including pre-conditioning for enhanced cytokine production, improved cell homing and strengthening of immunomodulatory properties, have been developed but the manufacture and handling of these cells for their use as advanced therapy medicinal products (ATMPs) remains insufficiently studied, and available data are mainly related to non-industrial processes. In the present article, we will review this topic, analyzing current information on the specific regulations, the selection of living donors as well as MSCs from different sources (bone marrow, adipose tissue, umbilical cord, etc.), in-process quality controls for ensuring cell efficiency and safety during all stages of the manual and automatic (bioreactors) manufacturing process, including cryopreservation, the use of cell banks, handling medicines, transport systems of ATMPs, among other related aspects, according to European and US legislation. Our aim is to provide a guide for a better, homogeneous manufacturing of therapeutic cellular products with special reference to MSCs.

Neural Differentiation Potential of Mesenchymal Stem Cells Enhanced by Biocompatible Chitosan-Gold Nanocomposites

Chitosan (Chi) is a natural polymer that has been demonstrated to have potential as a promoter of neural regeneration. In this study, Chi was prepared with various amounts (25, 50, and 100 ppm) of gold (Au) nanoparticles for use in in vitro and in vivo assessments. Each as-prepared material was first characterized by UV-visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), scanning electron microscopy (SEM), and Dynamic Light Scattering (DLS). Through the in vitro experiments, Chi combined with 50 ppm of Au nanoparticles demonstrated better biocompatibility. The platelet activation, monocyte conversion, and intracellular ROS generation was remarkably decreased by Chi–Au 50 pm treatment. Furthermore, Chi–Au 50 ppm could facilitate colony formation and strengthen matrix metalloproteinase (MMP) activation in mesenchymal stem cells (MSCs). The lower expression of CD44 in Chi–Au 50 ppm treatment demonstrated that the nanocomposites could enhance the MSCs undergoing differentiation. Chi–Au 50 ppm was discovered to significantly induce the expression of GFAP, β-Tubulin, and nestin protein in MSCs for neural differentiation, which was verified by real-time PCR analysis and immunostaining assays. Additionally, a rat model involving subcutaneous implantation was used to evaluate the superior anti-inflammatory and endothelialization abilities of a Chi–Au 50 ppm treatment. Capsule formation and collagen deposition were decreased. The CD86 expression (M1 macrophage polarization) and leukocyte filtration (CD45) were remarkably reduced as well. In summary, a Chi polymer combined with 50 ppm of Au nanoparticles was proven to enhance the neural differentiation of MSCs and showed potential as a biosafe nanomaterial for neural tissue engineering.

Mesenchymal Stem Cell Mechanisms of Action and Clinical Effects in Osteoarthritis: A Narrative Review

With the insufficient satisfaction rates and high cost of operative treatment for osteoarthritis (OA), alternatives have been sought. Furthermore, the inability of current medications to arrest disease progression has led to rapidly growing clinical research relating to mesenchymal stem cells (MSCs). The availability and function of MSCs vary according to tissue source. The three primary sources include the placenta, bone marrow, and adipose tissue, all of which offer excellent safety profiles. The primary mechanisms of action are trophic and immunomodulatory effects, which prevent the further degradation of joints. However, the function and degree to which benefits are observed vary significantly based on the exosomes secreted by MSCs. Paracrine and autocrine mechanisms prevent cell apoptosis and tissue fibrosis, initiate angiogenesis, and stimulate mitosis via growth factors. MSCs have even been shown to exhibit antimicrobial effects. Clinical results incorporating clinical scores and objective radiological imaging have been promising, but a lack of standardization in isolating MSCs prevents their incorporation in current guidelines.

Laparoscopic adipose-derived stem cell harvest technique with bipolar sealing device: Outcome in 12 dogs

Objective

This study aimed to describe the technique and clinical outcomes in dogs undergoing Laparoscopic Adipose‐Derived Stem Cell Harvest via bipolar sealing device (LADSCHB) for degenerative orthopaedic and neurologic disease.

Study Design

Descriptive retrospective case series.

Animals

Eleven dogs with orthopaedic disease and one dog with degenerative spinal disease were enrolled in the study.

Methods

Medical records of dogs undergoing LADSCHB were reviewed for signalment, weight, reason for the procedure, anaesthesia time, surgery time, other procedures performed, post‐operative pain protocols, incision size, amount of adipose tissue collected, number of viable cells collected, days to discharge, short‐term complications, and owner satisfaction.

Results

The median weight of the population was 34.2 kg (range 9.2–62 kg), the median surgery time was 39 min (range 15–45 min), mean incision length was 2.5 cm, the median amount of adipose collected was 60 g, and the median number of viable stem cells was 21 million cells. Conversion to open laparotomy was not needed. The most common reason for the harvest was osteoarthritis of the elbow (8/12 cases). Nine cases had other procedures performed at the same time as the harvest. No complications were noted during the procedure or within the post‐operative period. All owners surveyed were satisfied with the laparoscopic harvest procedure.

Conclusions

LADSCHB was technically feasible, productive, and not associated with any complications. This procedure was performed rapidly and was paired with other surgical procedures.

Clinical Significance

LADSCHB allows for stem cell harvest with commonly utilized laparoscopic equipment. This surgical technique could lead to the increased ability to treat patients with diseases that benefit from stem cell therapy.

Cell-based therapy of the elbow: evidence for lateral tendinopathy-a review on current treatments

PURPOSE

Cell-based therapies are on the rise in treating intra and extraarticular pathologies, trying to avoid surgical intervention and support local repair processes. Therefore, the aim was to summarize current evidence-based treatment options for a cell-based therapy around the elbow.

METHODS

Through a literature review up-to date treatment algorithms and therapies have been identified and have been rated according to their evidence level for clinical recommendation.

RESULTS

Regarding the four extraarticular anatomical regions of the elbow (anterior, medial, posterior and lateral) and the joint itself, the lateral elbow and its´ tendinopathies as well as the use of cell-based treatment options have been extensively studied and, therefore, allow for clear and evidence-based recommendations. The remaining three regions as wells as the intraarticular application do not show enough evidence for a clinical recommendation.

CONCLUSION

In conclusion the cell-based approach for treating elbow pathologies can only be recommended for the lateral elbow, as there has been shown sufficient evidence for the extraarticular application. It has to be mentioned, that the results from the lateral elbow maybe transferred to other extra-articular tendinopathies, as the lack of evidence may be due to the rare appearance of posterior, medial and anterior tendon affection. No recommendation can be given for intra-articular use.

LEVEL OF EVIDENCE

IV.

Bone Healing Materials in the Treatment of Recalcitrant Nonunions and Bone Defects

The usual treatment for bone defects and recalcitrant nonunions is an autogenous bone graft. However, due to the limitations in obtaining autogenous bone grafts and the morbidity associated with their procurement, various bone healing materials have been developed in recent years. The three main treatment strategies for bone defects and recalcitrant nonunions are synthetic bone graft substitutes (BGS), BGS combined with bioactive molecules, and BGS and stem cells (cell-based constructs). Regarding BGS, numerous biomaterials have been developed to prepare bone tissue engineering scaffolds, including biometals (titanium, iron, magnesium, zinc), bioceramics (hydroxyapatite (HA)), tricalcium phosphate (TCP), biopolymers (collagen, polylactic acid (PLA), polycaprolactone (PCL)), and biocomposites (HA/MONs@miR-34a composite coating, Bioglass (BG)-based ABVF-BG (antibiotic-releasing bone void filling) putty). Bone tissue engineering scaffolds are temporary implants that promote tissue ingrowth and new bone regeneration. They have been developed to improve bone healing through appropriate designs in terms of geometric, mechanical, and biological performance. Concerning BGS combined with bioactive molecules, one of the most potent osteoinductive growth factors is bone morphogenetic proteins (BMPs). In recent years, several natural (collagen, fibrin, chitosan, hyaluronic acid, gelatin, and alginate) and synthetic polymers (polylactic acid, polyglycolic acid, polylactic-coglycolide, poly(e-caprolactone) (PCL), poly-p-dioxanone, and copolymers consisting of glycolide/trimethylene carbonate) have been investigated as potential support materials for bone tissue engineering. Regarding BGS and stem cells (cell-based constructs), the main strategies are bone marrow stromal cells, adipose-derived mesenchymal cells, periosteum-derived stem cells, and 3D bioprinting of hydrogels and cells or bioactive molecules. Currently, significant research is being performed on the biological treatment of recalcitrant nonunions and bone defects, although its use is still far from being generalized. Further research is needed to investigate the efficacy of biological treatments to solve recalcitrant nonunions and bone defects.

Mesenchymal Stem Cells for Cryptoglandular Anal Fistula: Current State of Art

Anal fistula is a common disease that needs surgical treatment to be resolved. Despite a variety of surgical options, the major problem is still to cure complex fistulas without any recurrence in the long-term follow-up but, at the same time, to avoid an impairment of continence. In recent years, one solution has been the application of mesenchymal stem cells derived from adipose tissue, especially in association with other treatments, such as the use of fibrin glue or the previous application of a seton. Their initial use in fistulas associated with Crohn's disease has shown encouraging results. In this non-systematic review our aim is to analyze the use in cryptoglandular fistulas: the rate of healing is not so high, and the number of studies is limited. Therefore, further randomized controlled trials are needed to establish their efficacy in the case of complex cryptoglandular anal fistulas and their possible complications.

The promising role of autologous and allogeneic mesenchymal stromal cells in managing knee osteoarthritis. What is beyond Mesenchymal stromal cells?

Mesenchymal stromal cells (MSCs) express a wide range of properties anticipated to be beneficial for treating genetic, mechanical, and age-related degeneration in diseases such as osteoarthritis (OA). Although contemporary conservative management of OA is successful in many patients with mild-moderate OA, it often fails to improve symptoms in many patients who are not a candidate for any surgical management. Further, existing conservative treatment strategies do not prevent the progression of the disease and therefore fail to provide a long-term pain-free life. On the other hand, tremendous progress has been taking place in the exciting field of regenerative medicine involving MSCs (autologous and allogeneic), with promising translation taking place from basic science to the bedside. In this review, we comprehensively discuss the potential role of MSCs in treating OA, both autologous and off-the-shelf, allogeneic stem cells. Further, newer therapies are in the offing to treat OA, such as exosomes and growth factors.

Injectable xyloglucan hydrogels incorporating spheroids of adipose stem cells for bone and cartilage regeneration

Cartilage or bone regeneration approaches based on the direct injection of mesenchymal stem cells (MSCs) at the lesion site encounter several challenges, related to uncontrolled cell spreading and differentiation, reduced cell viability and poor engrafting. This work presents a simple and versatile strategy based on the synergic combination of in-situ forming hydrogels and spheroids of adipose stem cells (SASCs) with great potential for minimally invasive regenerative interventions aimed to threat bone and cartilage defects. Aqueous dispersions of partially degalactosylated xyloglucan (dXG) are mixed with SASCs derived from liposuction and either a chondroinductive or an osteoinductive medium. The dispersions rapidly set into hydrogels when temperature is brought to 37 °C. The physico-chemical and mechanical properties of the hydrogels are controlled by polymer concentration. The hydrogels, during 21 day incubation at 37 °C, undergo significant structural rearrangements that support cell proliferation and spreading. In formulations containing 1%w dXG cell viability increases up to 300% for SASCs-derived osteoblasts and up to 1000% for SASCs-derived chondrocytes if compared with control 2D cultures. The successful differentiation into the target cells is supported by the expression of lineage-specific genes. Cell-cell and cell-matrix interactions are also investigated. All formulations resulted injectable, and the incorporated cells are fully viable after injection.

Inhibitory Effect of Bovine Adipose-Derived Mesenchymal Stem Cells on Lipopolysaccharide Induced Inflammation of Endometrial Epithelial Cells in Dairy Cows

Endometritis is a disease that affects reproductive health in dairy cows and causes serious economic damage to the dairy industry world-wide. Although in recent years, the application of mesenchymal stem cell (MSC) therapy for the treatment of inflammatory diseases has attracted much attention, there are few reports of the use of MSCs in dairy cows. In the present study, our objective was to explore the inhibitory effects of bovine adipose-derived mesenchymal stem cells (bAD-MSCs) on lipopolysaccharide (LPS) induced inflammation in bovine endometrial epithelial cells (bEECs) along with the potential underlying molecular mechanisms. We characterized isolated bAD-MSCs using cell surface marker staining and adipogenic/osteogenic differentiation, and analyzed them using immunofluorescence, flow cytometry (surface marker staining), and adipogenic and osteogenic differentiation. Furthermore, to understand the anti-inflammatory effects of bAD-MSCs on LPS induced bEEC inflammation, we used a bAD-MSC/bEEC co-culture system. The results showed that bAD-MSC treatments could significantly decrease LPS induced bEEC apoptosis and pro-inflammatory cytokine expression levels, such as interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α). Furthermore, our results showed that bAD-MSC treatments could also significantly downregulate LPS induced p38, IkB-a, and JAK1 phosphorylation and Bax protein expression levels, which are closely related to inflammatory progress and cellular apoptosis in bEECs. Our findings demonstrate that bAD-MSCs play an inhibitory role in LPS induced bEEC inflammation and provide new insights for the clinical therapy of endometritis in dairy cows.

A High-Content Screen for C/EBPα Expression Identifies Novel Therapeutic Agents in Dedifferentiated Liposarcoma

PURPOSE

Dedifferentiated liposarcoma (DDLS), one of the most common and aggressive sarcomas, infrequently responds to chemotherapy. DDLS survival and growth depend on underexpression of C/EBPα, a tumor suppressor and transcriptional regulator controlling adipogenesis. We sought to screen and prioritize candidate drugs that increase C/EBPα expression and may therefore serve as differentiation-based therapies for DDLS.

EXPERIMENTAL DESIGN

We screened known bioactive compounds for the ability to restore C/EBPα expression and inhibit proliferation selectively in two DDLS cell lines but not in normal adipose-derived stem cells (ASC). Selected hits' activity was validated, and the mechanism of the most potent, SN-38, was investigated. The in vivo efficacy of irinotecan, the prodrug of SN-38, was evaluated in DDLS xenograft models.

RESULTS

Of 3,119 compounds, screen criteria were met by 19. Validation experiments confirmed the DDLS selectivity of deguelin, emetine, and SN-38 and showed that they induce apoptosis in DDLS cells. SN-38 had the lowest IC₅₀ (approximately 10 nmol/L), and its pro-apoptotic effects were countered by knockdown of CEBPA but not of TP53. Irinotecan significantly inhibited tumor growth at well-tolerated doses, induced nuclear expression of C/EBPα, and inhibited HIF1α expression in DDLS patient-derived and cancer cell line xenograft models. In contrast, doxorubicin, the most common treatment for nonresectable DDLS, reduced tumor growth by 30% to 50% at a dose that caused weight loss.

CONCLUSIONS

This high-content screen revealed potential treatments for DDLS. These include irinotecan, which induces apoptosis of DDLS cells in a C/EBPα-dependent, p53-independent manner, and should be clinically evaluated in patients with advanced DDLS.

Efficacy and Safety of Treatment of Complex Idiopathic Fistula-in-Ano Using Autologous Centrifuged Adipose Tissue Containing Progenitor Cells: A Randomized Controlled Trial

BACKGROUND

Mesenchymal stem cells derived from adipose tissue have been successfully used to promote sphincter-saving anal fistula healing.

OBJECTIVE

The aim of this study was to evaluate the efficacy and safety of the use of autologous centrifuged adipose tissue in the healing process of cryptoglandular complex anal fistulas.

DESIGN

This is a randomized controlled trial.

SETTINGS

This study was conducted at a single center.

PATIENTS

Patients with complex perianal fistulas not associated with Crohn's disease were included. Rectovaginal fistulas were not included.

INTERVENTIONS

Patients were randomly allocated to receive treatment with centrifuged adipose tissue injection (experimental group) and without injection (control group) in combination with fistula surgery.

MAIN OUTCOME MEASURES

The primary outcome was defined as the proportion of patients with complete fistula closure at 4 weeks (short-term outcome) and 6 months after surgery (long-term outcome). Healing was defined as when the external opening was closed with no perianal discharge on clinical assessment. The secondary outcome was safety that was evaluated by the analysis of adverse events up to 3 months after surgery. Pelvic MRI was performed at 3 months to assure safety and the accuracy of the clinical determination of healing. Postoperative pain, return to work/daily activities, persistent closure at 6 months, fecal incontinence, and patient satisfaction were evaluated.

RESULTS

Fifty-eight patients who received centrifuged adipose tissue injection and 58 patients who did not receive centrifuged adipose tissue injection were included in the safety and efficacy analysis. After 4 weeks, the healing rate was 63.8% in the experimental group compared with 15.5% in the control group (p < 0.001). No major adverse events were recorded. Postoperative anal pain was significantly lower in the injection group. Time taken to return to work/daily activities was significantly shorter in the experimental group (3 days) than in the control group (17 days). At 6 months, persistent closure was similar in the 2 groups (86.2% vs 81%). Fecal Incontinence Score at 6 months after surgery was identical to the preoperative score. Patient satisfaction was high in both groups.

LIMITATIONS

The absence of blinding, the lack of correlation between stem cell content, and the clinical outcome were limitations of the study.

CONCLUSIONS

Autologous centrifuged adipose tissue injection may represent a safe, efficacious, and inexpensive option for the treatment of complex fistula-in-ano. See Video Abstract at http://links.lww.com/DCR/B607.

CLINICAL TRIALS REGISTRATION

URL: https://www.clinicaltrials.gov. Identifier: NCT04326907.

EFICACIA Y SEGURIDAD DEL TRATAMIENTO DE LA FSTULA ANAL COMPLEJA IDIOPTICA UTILIZANDO TEJIDO ADIPOSO CENTRIFUGADO AUTLOGO QUE CONTIENE CLULAS PROGENITORAS UN ENSAYO CONTROLADO ALEATORIO

ANTECEDENTES:Las células madre mesenquimales derivadas del tejido adiposo se han utilizado con éxito para promover la curación de la fístula anal con preservación de esfínter.OBJETIVO:El objetivo de este estudio fue evaluar la eficacia y seguridad del uso de tejido adiposo autólogo centrifugado en el proceso de cicatrización de fístulas anales complejas de origen criptoglandular.DISEÑO:Ensayo controlado aleatorio.ENTORNO CLÍNICO:Estudio unicéntrico.PACIENTES:Se incluyeron pacientes con fístulas perianales complejas no asociadas a Enfermedad de Crohn. No se incluyeron las fístulas rectovaginales.INTERVENCIONES:Los pacientes fueron asignados aleatoriamente para recibir tratamiento con inyección de tejido adiposo centrifugado (grupo experimental) y sin inyección (grupo de control) en combinación con cirugía de fístula.PRINCIPALES MEDIDAS DE VALORACIÓN:El resultado primario se definió como la proporción de pacientes con cierre completo de la fístula a las 4 semanas (resultado a corto plazo) y 6 meses después de la cirugía (resultado a largo plazo). La curación se definió cuando orificio externo se cerró sin secreción perianal en la valoración clínica. El resultado secundario fue la seguridad que se evaluó mediante el análisis de los eventos adversos (EA) hasta 3 meses después de la cirugía. La resonancia magnética pélvica se realizó a los 3 meses para garantizar la seguridad y la precisión clínica de la curación. Se evaluó el dolor postoperatorio, el regreso al trabajo / actividades diarias, el cierre persistente a los 6 meses, la incontinencia fecal y la satisfacción del paciente.RESULTADOS:Cincuenta y ocho pacientes que recibieron inyección de tejido adiposo centrifugado y 58 pacientes que no recibieron inyección de tejido adiposo centrifugado se incluyeron en el análisis de seguridad y eficacia. Después de 4 semanas, la tasa de curación fue del 63,8% en el grupo experimental en comparación con el 15,5% en el grupo de control (p <0,001). No se registraron eventos adversos importantes. El dolor anal posoperatorio fue significativamente menor en el grupo de inyección. El tiempo necesario para volver al trabajo / actividades diarias fue significativamente menor en el grupo experimental (3 días) con respecto al grupo de control (17 días). A los 6 meses, el cierre persistente fue similar en los dos grupos (86,2% vs 81%). La puntuación de incontinencia fecal a los 6 meses después de la cirugía fue idéntica a la puntuación preoperatoria. La satisfacción del paciente fue muy alta en ambos grupos.LIMITACIONES:Ausencia de cegamiento, falta de correlación entre el contenido de células madre y el resultado clínico.CONCLUSIONES:La inyección de tejido adiposo centrifugado autólogo puede representar una opción segura, eficaz y económica para el tratamiento de la fístula anal compleja.Registro de ensayos clínicos: www.clinicaltrials.gov, identificador NCT04326907; No patrocinado.Consulte Video Resumen en http://links.lww.com/DCR/B607.

Current Biomaterial-Based Bone Tissue Engineering and Translational Medicine

Bone defects cause significant socio-economic costs worldwide, while the clinical "gold standard" of bone repair, the autologous bone graft, has limitations including limited graft supply, secondary injury, chronic pain and infection. Therefore, to reduce surgical complexity and speed up bone healing, innovative therapies are needed. Bone tissue engineering (BTE), a new cross-disciplinary science arisen in the 21st century, creates artificial environments specially constructed to facilitate bone regeneration and growth. By combining stem cells, scaffolds and growth factors, BTE fabricates biological substitutes to restore the functions of injured bone. Although BTE has made many valuable achievements, there remain some unsolved challenges. In this review, the latest research and application of stem cells, scaffolds, and growth factors in BTE are summarized with the aim of providing references for the clinical application of BTE.

Attenuation of Knee Osteoarthritis Progression in Mice through Polarization of M2 Macrophages by Intra-Articular Transplantation of Non-Cultured Human Adipose-Derived Regenerative Cells

Adipose-derived regenerative cells (ADRCs) are non-cultured heterogeneous or mixed populations of cells obtained from adipose tissue by collagenase digestion. The injection of ADRCs have been tried clinically for the treatment of osteoarthritis (OA). The purpose of this study was to evaluate the effect of intra-articular transplantation of human ADRCs on OA progression in mice and the effect of ADRCs on macrophage polarization. In in vivo experiments, BALB/c-nu mice with knee OA received intra-articular transplantation of either phosphate buffered-saline or human ADRCs. OA progression was evaluated histologically and significantly attenuated in the ADRC group at both four and eight weeks postoperatively. The expression of OA-related proteins in the cartilage and macrophage-associated markers in the synovium were examined by immunohistochemistry. The numbers of MMP-13-, ADAMTS-5-, IL-1β-, IL-6- and iNOS-positive cells significantly decreased, and type II collagen- and CD206-positive cells were more frequently detected in the ADRC group compared with that in the control group. In vitro co-culture experiments showed that ADRCs induced macrophage polarization toward M2. The results of this study suggest that the intra-articular transplantation of human ADRCs could attenuate OA progression possibly by reducing catabolic factors in chondrocytes and modulating macrophage polarization.

Mesenchymal stem cells for enhancing biological healing after meniscal injuries

The meniscus is a semilunar fibrocartilage structure that plays important roles in maintaining normal knee biomechanics and function. The roles of the meniscus, including load distribution, force transmission, shock absorption, joint stability, lubrication, and proprioception, have been well established. Injury to the meniscus can disrupt overall joint stability and cause various symptoms including pain, swelling, giving-way, and locking. Unless treated properly, it can lead to early degeneration of the knee joint. Because meniscal injuries remain a significant challenge due to its low intrinsic healing potential, most notably in avascular and aneural inner two-thirds of the area, more efficient repair methods are needed. Mesenchymal stem cells (MSCs) have been investigated for their therapeutic potential in vitro and in vivo. Thus far, the application of MSCs, including bone marrow-derived, synovium-derived, and adipose-derived MSCs, has shown promising results in preclinical studies in different animal models. These preclinical studies could be categorized into intra-articular injection and tissue-engineered construct application according to delivery method. Despite promising results in preclinical studies, there is still a lack of clinical evidence. This review describes the basic knowledge, current treatment, and recent studies regarding the application of MSCs in treating meniscal injuries. Future directions for MSC-based approaches to enhance meniscal healing are suggested.

Age-related alteration in characteristics, function, and transcription features of ADSCs

BACKGROUND AND OBJECTIVES

Adipose tissue-derived stem cells (ADSCs) autologous transplantation has been a promising strategy for aging-related disorders. However, the relationship between ADSCs senescence and organismal aging has not been clearly established. Therefore, we aimed at evaluating senescence properties of ADSCs from different age donors and to verify the influence of organismal aging on the proliferation and function of ADSCs in vitro, providing the theoretical basis for the clinical application of autologous ADSCs transplantation.

METHODS AND RESULTS

The ADSCs were obtained from 1-month-old and 20-month-old mice. The cells characteristics, functions, gene expression levels, apoptosis proportion, cell cycle, SA-β-gal staining, and transcription features were evaluated. Compared to ADSCs from 1-month-old mice, ADSCs from 20-month-old mice exhibited some senescence-associated changes, including inhibited abilities to proliferate. Moreover, differentiation abilities, cell surface markers, and cytokines secreting differed between 1M and 20M ADSCs. SA-β-Gal staining did not reveal differences between the two donor groups, while cells exhibited more remarkable age-related changes through continuous passages. Based on transcriptome analysis and further detection, the CCL7-CCL2-CCR2 axis is the most probable mechanism for the differences.

CONCLUSIONS

ADSCs from old donors have some age-related alterations. The CCL7-CCL2-CCR2 axis is a potential target for gene therapy to reduce the harmful effects of ADSCs from old donors. To improve on autologous transplantation, we would recommend that ADSCs should be cryopreserved in youth with a minimum number of passages or block CCL7-CCL2-CCR2 to abolish the effects of age-related alterations in ADSCs through the Chemokine signaling pathway.

Differentiation Behaviour of Adipose-Derived Stromal Cells (ASCs) Seeded on Polyurethane-Fibrin Scaffolds In Vitro and In Vivo

Adipose-derived stromal cells (ASCs) are a promising cell source for tissue engineering and regenerative medicine approaches for cartilage replacement. For chondrogenic differentiation, human (h)ASCs were seeded on three-dimensional polyurethane (PU) fibrin composites and induced with a chondrogenic differentiation medium containing TGF-ß3, BMP-6, and IGF-1 in various combinations. In addition, in vitro predifferentiated cell-seeded constructs were implanted into auricular cartilage defects of New Zealand White Rabbits for 4 and 12 weeks. Histological, immunohistochemical, and RT-PCR analyses were performed on the constructs maintained in vitro to determine extracellular matrix (ECM) deposition and expression of specific cartilage markers. Chondrogenic differentiated constructs showed a uniform distribution of cells and ECM proteins. RT-PCR showed increased gene expression of collagen II, collagen X, and aggrecan and nearly stable expression of SOX-9 and collagen I. Rabbit (r)ASC-seeded PU-fibrin composites implanted in ear cartilage defects of New Zealand White Rabbits showed deposition of ECM with structures resembling cartilage lacunae by Alcian blue staining. However, extracellular calcium deposition became detectable over the course of 12 weeks. RT-PCR showed evidence of endochondral ossification during the time course with the expression of specific marker genes (collagen X and RUNX-2). In conclusion, hASCs show chondrogenic differentiation capacity in vitro with the expression of specific marker genes and deposition of cartilage-specific ECM proteins. After implantation of predifferentiated rASC-seeded PU-fibrin scaffolds into a cartilage defect, the constructs undergo the route of endochondral ossification.

Use of Autologous Adipose-Derived Stromal Vascular Fractions in Revision Rhinoplasty for Severe Contractures in Asian Patients

BACKGROUND

Autologous adipose-derived stromal vascular fraction treatments have been shown to elicit antiinflammatory, antifibrotic, immunomodulatory, angiogenic, and regenerative effects. Injections of adipose-derived stromal vascular fraction have been used to treat severely scarred tissues.

METHODS

Revision septorhinoplasty was performed in 40 patients with severely contracted noses. Clinical outcomes and adverse events were compared between one group of patients treated with adjuvant adipose-derived stromal vascular fraction injections and a control group of patients treated with adjuvant 0.9% preservative-free saline injections.

RESULTS

In the adipose-derived stromal vascular fraction group, nasal lengths were estimated at 4.2 ± 0.2 cm at baseline to 5.1 ± 0.2 cm at 18 months after revision septorhinoplasty. The lengths of nasal tip projection improved from 2.2 ± 0.2 cm at baseline to 2.9 ± 0.1 cm 18 months after surgery. In addition, nasofrontal angles improved from 125.6 ± 5.1 degrees at baseline to 128.1 ± 4.8 degrees 18 months after surgery. Nasolabial angles in the adipose-derived stromal vascular fraction group were estimated at 105.8 ± 6.5 degrees at baseline and 94.9 ± 5.6 degrees 18 months after surgery. Of these, nasal length, nasal tip projection, and nasolabial angle, but not nasofrontal angle, values improved more in the adipose-derived stromal vascular fraction group than in the control group.

CONCLUSION

Preoperative and postoperative adjuvant adipose-derived stromal vascular fraction treatment markedly improved the therapeutic outcomes of revision rhinoseptoplasty of severely contracted noses without major side effects.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Nonoperative and Operative Soft-Tissue and Cartilage Regeneration and Orthopaedic Biologics of the Knee: An Orthoregeneration Network (ON) Foundation Review

Orthoregeneration is defined as a solution for orthopedic conditions that harnesses the benefits of biology to improve healing, reduce pain, improve function, and optimally, provide an environment for tissue regeneration. Options include: drugs, surgical intervention, scaffolds, biologics as a product of cells, and physical and electro-magnetic stimuli. The goal of regenerative medicine is to enhance the healing of tissue after musculoskeletal injuries as both isolated treatment and adjunct to surgical management, using novel therapies to improve recovery and outcomes. Various orthopaedic biologics (orthobiologics) have been investigated for the treatment of pathology involving the knee, including symptomatic osteoarthritis and chondral injuries, as well as injuries to tendon, meniscus, and ligament, including the anterior cruciate ligament. Promising and established treatment modalities include hyaluronic acid (HA) in liquid or scaffold form; platelet-rich plasma (PRP); bone marrow aspirate (BMA) comprising mesenchymal stromal cells (MSCs), hematopoietic stem cells, endothelial progenitor cells, and growth factors; connective tissue progenitor cells (CTPs) including adipose-derived mesenchymal stem cells (AD-MSCs) and tendon-derived stem cells (TDSCs); matrix cell-based therapy including autologous chondrocytes or allograft; vitamin D; and fibrin clot. Future investigations should standardize solution preparations, because inconsistent results reported may be due to heterogeneity of HA, PRP, BMAC, or MSC preparations and regimens, which may inhibit meaningful comparison between studies to determine the true efficacy and safety for each treatment.

Efficacy and safety of autologous adipose tissue-derived stem cell therapy for children with refractory Crohn's complex fistula: a Phase IV clinical study

Purpose

Autologous adipose tissue-derived stem cells (ASCs) have been proposed for patients with refractory Crohn disease, but research is lacking in pediatric patients. This Phase IV study evaluated the efficacy and safety of ASCs in children with refractory Crohn's fistulae.

Methods

Patients with a refractory Crohn's fistula who did not have conventional therapy for more than 3 months or with a recurrent complex Crohn's fistula were included. All patients were at least 14 years old. Patients with infection, poor condition, or active Crohn disease with a disease activity index of 450 and above were excluded. Five patients were treated with ASCs from 2014 to 2015 in Asan Medical Center. ASC administration was adjusted according to fistula size (1 mL per cm²). We evaluated the efficacy and safety 8 weeks after injection and followed patients for 6 months.

Results

Fistulae were healed in 4 patients by 8 weeks after ASC injection. Of these 4 patients, 1 had complete fistula closure and sustainability after 6 months. The other 3 with healing effects had less than 50% fistula closure by 6 months. None of these 4 patients have persistent fistulae. One patient had no healing effect, and seton ligation was performed 8 months after ASC injection. There were no adverse effects related to ASC administration.

Conclusion

ASC therapy is a simple and well-tolerated therapeutic option for children with refractory Crohn's complex fistulae. Complete closure was well-sustained. However, more data from a larger number of patients are needed.

Comparison of the Characteristics of Breast Milk-derived Stem Cells with the Stem Cells Derived from the Other Sources: A Comparative Review

Breast milk (BrM) not only supplies nutrition, but it also contains a diverse population of cells. It has been estimated that up to 6% of the cells in human milk possess the characteristics of mesenchymal stem cells (MSC). Available data also indicate that these cells are multipotent and capable of self-renewal and differentiation with other cells. In this review, we have compared different characteristics, such as CD markers, differentiation capacity, and morphology of stem cells, derived from human breast milk (hBr-MSC) with human bone marrow (hBMSC), Wharton's jelly (WJMSC), and human adipose tissue (hADMSC). Through the literature review, it was revealed that human breast milk-derived stem cells specifically express a group of cell surface markers, including CD14, CD31, CD45, and CD86. Importantly, a group of markers, CD13, CD29, CD44, CD105, CD106, CD146, and CD166, were identified, which were common in the four sources of stem cells. WJMSC, hBMSC, hADMSC, and hBr-MSC are potently able to differentiate into the mesoderm, ectoderm, and endoderm cell lineages. The ability of hBr-MSCs todifferentiate into the neural stem cells, neurons, adipocyte, hepatocyte, chondrocyte, osteocyte, and cardiomyocytes has made these cells a promising source of stem cells in regenerative medicine, while isolation of stem cells from the commonly used sources, such as bone marrow, requires invasive procedures. Although autologous breast milk-derived stem cells are an accessible source for women who are in the lactation period, breast milk can be considered as a source of stem cells with high differentiation potential without any ethical concern.

Can Autologous Adipose-Derived Mesenchymal Stem Cell Transplantation Improve Sexual Function in People with Sexual Functional Deficiency?

BACKGROUND

Sexual functional deficiency occurs at some point in life and becomes a problematic issue in middle-aged adulthood. Regenerative medicine, especially mesenchymal stem cell (MSC) transplantation, has developed extensively, with preclinical and clinical trials emphasizing the benefits of stem cell therapy for restoration of sexual deficiency. This study was designed to develop a new therapeutic stem cell treatment for people with sexual functional deficiency.

METHODS

Thirty-one patients, including 15 males and 16 females with a medical history of reduced sexual activity, met the inclusion criteria and were enrolled in the study, phase I/IIa clinical trial with a 12-month follow-up. Adipose tissue-derived mesenchymal stem/stromal cells (ADSC) were isolated by type I collagenase digestion and cultured at the Stem Cell Core Facility under ISO 14644-1. Each participant received 1 million cells/kg of body weight via the intravenous route. Safety was evaluated by assessing the occurrence of adverse events or severe adverse events. Efficacy was assessed in males by monitoring testosterone levels and administering the International Index of Erectile Function (IIEF) questionnaire and in females by monitoring anti-Mullerian hormone (AMH), estradiol (E2), and follicle-stimulating hormone (FSH) levels and administering the Female Sexual Functioning Index (FSFI) questionnaire at baseline and 3-, 6-, and 12-months post-transplantation.

RESULTS

There was no occurrence of severe adverse events after ADSC administration in our study. Post-transplantation sexual satisfaction was observed in all patients enrolled in this study. Testosterone levels in males increased soon after transplantation and were maintained at high levels for up to 6 months before decreasing again at the 12-month follow-up. No significant changes in AMH, FSH or E2 levels were recorded in female patients.

CONCLUSIONS

Autologous ADSC infusion is a potential therapeutic option for patients with reduced sexual activity, especially for male patients.

TRIAL REGISTRATION

ClinicalTrials.gov. NCT03346967, Registered November 20, 2017.

"Treatment of En Coup de Sabre Deformity with Fat Grafting and Demineralized Bone Matrix: A Case Series"

En coup de sabre deformity (ECDS) is a form of localized scleroderma in the frontoparietal region caused by progressive subcutaneous tissue atrophy and bony defect. Although ECDS involves two layers, skin/subcutaneous tissue and bone, the existing literature mainly focuses only on treating the skin/subcutaneous tissue layer. In this case series, we aimed to propose a novel approach that includes the combined use of fat grafting and demineralized bone matrix (DBM). Four patients with ECDS deformity, operated between February 2016 and October 2018, were retrospectively evaluated. All the patients were treated with the novel approach. Patients were evaluated with localized scleroderma scale and computed tomography (CT) scan in the preoperative period and at the annual follow-up. We observed remarkable improvement in the localized scleroderma scale including appearance, palpation, and size scores in all patients at the annual follow-up. CT scans at the annual follow-up revealed new callus formation at the bony defect area in all patients. Reinforcing fat grafting with DBM could promote healing of the bony and skin/subcutaneous tissue defects associated with ECDS.

A chondroitin sulfate based injectable hydrogel for delivery of stem cells in cartilage regeneration

Chondroitin sulfate (CS), as a popular material for cartilage tissue engineering scaffolds, has been extensively studied and reported for its safety and excellent biocompatibility. However, the rapid degradation of pure CS scaffolds has brought a challenge to regenerate neo-tissue similar to natural articular cartilage effectively. Meanwhile, the poly(ethene glycol) (PEG) -based biopolymer is frequently applied as a structural constituent material because of its remarkable mechanical properties, long-lasting in vivo stability, and hypo-immunity. Here, we report that the combination of CS and hyperbranched multifunctional PEG copolymer (HB-PEG) could synergistically promote cartilage repair. The thiol functionalised CS (CS-SH)/HB-PEG hydrogel scaffolds were fabricated via thiol-ene reaction, which exhibits rapid gelation, excellent mechanical properties and prolonged degradation properties. We found that rat adipose-derived mesenchymal stem cells presented great cell viability and improved chondrogenesis in CS-SH/HB-PEG hydrogels. Moreover, the injectable hydrogel scaffolds reduced stem cell inflammatory response, consistent with the well-documented anti-inflammatory activities of CS.

Cell-based therapies for the treatment of sports injuries of the upper limb

Introduction: The use of cell-based therapies in the management of sports injuries of the upper limb is increasingly popular despite the limited scientific evidence available for their use. We aim to evaluate the evidence for the use of cell-based therapies in these injuries and recommend areas for further research.Areas covered: In accordance with a published protocol (PROSPERO; Registration No. CRD42020193258), a comprehensive search of the literature was performed using the MEDLINE and EMBASE databases from inception to June 2020. All human studies reporting on the clinical, histological, or radiological outcomes following the use of cell-based therapies in the management of epicondylitis or rotator cuff pathology were included in this study. This resulted in 22 studies being included in this review, all of which underwent risk of bias assessments.Expert opinion: The evidence for the use of cell-based therapies in upper limb sports injuries is limited and generally of low quality. Given the heterogeneity in the cell types used, their harvesting methods and cell amounts, future research should be targeted at developing standardization of the reporting of these studies and more direct comparative studies looking at the efficacy of the different cell types.