Adipose tissue-derived stromal cells as a novel option for regenerative cell therapy

Potential Consequences of the Use of Adipose-Derived Stem Cells in the Treatment of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) ranks as the most prevalent of primary liver cancers and stands as the third leading cause of cancer-related deaths. Early-stage HCC can be effectively managed with available treatment modalities ranging from invasive techniques, such as liver resection and thermoablation, to systemic therapies primarily employing tyrosine kinase inhibitors. Unfortunately, these interventions take a significant toll on the body, either through physical trauma or the adverse effects of pharmacotherapy. Consequently, there is an understandable drive to develop novel HCC therapies. Adipose-derived stem cells (ADSCs) are a promising therapeutic tool. Their facile extraction process, coupled with the distinctive immunomodulatory capabilities of their secretome, make them an intriguing subject for investigation in both oncology and regenerative medicine. The factors they produce are both enzymes affecting the extracellular matrix (specifically, metalloproteinases and their inhibitors) as well as cytokines and growth factors affecting cell proliferation and invasiveness. So far, the interactions observed with various cancer cell types have not led to clear conclusions. The evidence shows both inhibitory and stimulatory effects on tumor growth. Notably, these effects appear to be dependent on the tumor type, prompting speculation regarding their potential inhibitory impact on HCC. This review briefly synthesizes findings from preclinical and clinical studies examining the effects of ADSCs on cancers, with a specific focus on HCC, and emphasizes the need for further research.

How long does the biological effect of a red light-emitting diode last on adipose-derived mesenchymal stem cells?

This research investigated the duration of the influence of red light-emitting diodes (LED, 630 nm; output power: 2452.5 mW; laser beam: 163.5 cm2; irradiance: 15 mW/cm2; radiant exposure: 4 J/cm2) on different periods after irradiation (6, 12, 24, 48, and 72 h) on adipose-derived mesenchymal stem cells' (AdMSCs) metabolism and paracrine factors. AdMSCs were irradiated three times every 48 h. Twenty-four hours after the last irradiation, there was a higher MTT absorbance, followed by a decrease after 48 h. The cells' secretome showed increased levels of IL-6 and VEGF after 12 and 24 h, but this was reversed after 48 h. Additionally, LED irradiation resulted in higher levels of nitrite and did not affect oxidative stress markers. LED irradiation had significant effects on AdMSCs after 24 h compared to other groups and its control group.

Adipose-Derived Stromal Cell-Based Therapies for Radiation-Induced Fibrosis

Significance: Half of all cancer patients receive radiation therapy as a component of their treatment regimen, and the most common resulting complication is radiation-induced fibrosis (RIF) of the skin and soft tissue. This thickening of the dermis paired with decreased vascularity results in functional limitations and esthetic concerns and poses unique challenges when considering surgical exploration or reconstruction. Existing therapeutic options for RIF of the skin are limited both in scope and efficacy. Cell-based therapies have emerged as a promising means of utilizing regenerative cell populations to improve both functional and esthetic outcomes, and even as prophylaxis for RIF. Recent Advances: As one of the leading areas of cell-based therapy research, adipose-derived stromal cells (ADSCs) demonstrate significant therapeutic potential in the treatment of RIF. The introduction of the ADSC-augmented fat graft has shown clinical utility. Recent research dedicated to characterizing specific ADSC subpopulations points toward further granularity in understanding of the mechanisms driving the well-established clinical outcomes seen with fat grafting therapy. Critical Issues: Various animal models of RIF demonstrated improved clinical outcomes following treatment with cell-based therapies, but the cellular and molecular basis underlying these effects remains poorly understood. Future Directions: Recent literature has focused on improving the efficacy of cell-based therapies, most notably through (1) augmentation of fat grafts with platelet-rich plasma and (2) the modification of expressed RNA through epitranscriptomics. For the latter, new and promising gene targets continue to be identified which have the potential to reverse the effects of fibrosis by increasing angiogenesis, decreasing inflammation, and promoting adipogenesis.

Adipose-Derived Stem Cells to Treat Ischemic Diseases: The Case of Peripheral Artery Disease

Critical limb ischemia incidence and prevalence have increased over the years. However, there are no successful treatments to improve quality of life and to reduce the risk of cardiovascular and limb events in these patients. Advanced regenerative therapies have focused their interest on the generation of new blood vessels to repair tissue damage through the use of stem cells. One of the most promising sources of stem cells with high potential in cell-based therapy is adipose-derived stem cells (ASCs). ASCs are adult mesenchymal stem cells that are relatively abundant and ubiquitous and are characterized by a multilineage capacity and low immunogenicity. The proangiogenic benefits of ASCs may be ascribed to: (a) paracrine secretion of proangiogenic molecules that may stimulate angiogenesis; (b) secretion of microvesicles/exosomes that are also considered as a novel therapeutic prospect for treating ischemic diseases; and (c) their differentiation capability toward endothelial cells (ECs). Although we know the proangiogenic effects of ASCs, the therapeutic efficacy of ASCs after transplantation in peripheral artery diseases patients is still relatively low. In this review, we evidence the potential therapeutic use of ASCs in ischemic regenerative medicine. We also highlight the main challenges in the differentiation of these cells into functional ECs. However, significant efforts are still needed to ascertain relevant transcription factors, intracellular signaling and interlinking pathways in endothelial differentiation.

Light-emitting Diode Can Enhance the Metabolism and Paracrine Action of Mesenchymal Stem Cells

This study investigated the influence of red light-emitting diodes (LED, 630 nm) on different irradiation parameters and the number of applications on mesenchymal stem cells derived from adipose tissue (AdMSCs) metabolism and paracrine factors. The AdMSCs were irradiated with a LEDbox device (output power: 2452.5 mW; laser beam: 163.5 cm2 ; irradiance: 15 mW cm-2 ) using radiant exposures of 0.5, 2, and 4 J cm-2 , respectively. AdMSCs were irradiated once or every 48 h up to three irradiations. All molecular analyses were performed 24 h after the last irradiation. LED did not induce changes in cell count, DNA damage, and oxidative stress. A significant repercussion of the LED has been noticed after three irradiations with 4 J cm-2 . AdMSCs had higher levels of IL-6, IGF-1, and NOx index. A higher ATP content and MMT/Resazurin assay were identified in AdMSCs irradiated three times with 4 J cm-2 . Mitochondrial basal respiration, maximal respiration and proton leak under metabolic stress were reduced by 0.5 and 2 J cm-2 irradiations. These data showed that three LED irradiations with 4 J cm-2 may be a suitable parameter for future AdMSCs therapy because of its improved metabolic activity, ATP content, and IL-6, IGF-1, and nitric oxide secretion.

In Vitro Study of a Novel Vibrio alginolyticus-Based Collagenase for Future Medical Application

Mesenchymal stem cells extracted from adipose tissue are particularly promising given the ease of harvest by standard liposuction and reduced donor site morbidity. This study proposes a novel enzymatic method for isolating stem cells using Vibrio alginolyticus collagenase, obtaining a high-quality product in a reduced time. Initially, the enzyme concentration and incubation time were studied by comparing cellular yield, proliferation, and clonogenic capacities. The optimized protocol was phenotypically characterized, and its ability to differentiate in the mesodermal lineages was evaluated. Subsequently, that protocol was compared with two Clostridium histolyticum-based collagenases, and other tests for cellular integrity were performed to evaluate the enzyme's effect on expanded cells. The best results showed that using a concentration of 3.6 mg/mL Vibrio alginolyticus collagenase allows extracting stem cells from adipose tissue after 20 min of enzymatic reaction like those obtained with Clostridium histolyticum-based collagenases after 45 min. Moreover, the extracted cells with Vibrio alginolyticus collagenase presented the phenotypic characteristics of stem cells that remain after culture conditions. Finally, it was seen that Vibrio alginolyticus collagenase does not reduce the vitality of expanded cells as Clostridium histolyticum-based collagenase does. These findings suggest that Vibrio alginolyticus collagenase has great potential in regenerative medicine, given its degradation selectivity by protecting vital structures for tissue restructuration.

Autologous Shuffling Lipo-Aspirated Fat Combined Mechanical Stretch in Revision Rhinoplasty for Severe Contractures in Asian Patients

BACKGROUND

A severely contracted nose is a common occurrence. Intraoperative expansion is not sufficient to soften the severely constricted nasal envelope, which poses challenges in revision rhinoplasty. In recent years, adjuvant therapies, including nasal fat grafting and cell component injection, are applied before revision rhinoplasty to soften the nasal envelope. Herein, autologous shuffling lipo-aspirated fat and manual mechanical stretch were combined as adjuvant therapy before revision rhinoplasty.

METHODS

A total of 24 patients with severe nasal contracture were included in this study. Of these, 8 received autologous shuffling lipo-aspirated fat and manual mechanical stretch before revision rhinoplasty (comprehensive therapy), 8 underwent mechanical stretch and revision rhinoplasty, and 8 patients underwent only revision rhinoplasty. The objective and subjective outcome assessment was processed in the follow-up period of 6 months. Nasal length, nasal tip projection, nasofrontal angle, and nasolabial angle were measured, and potential complications were assessed.

RESULTS

All 24 patients underwent a successful revision rhinoplasty. In the comprehensive therapy group, no patient had postoperative wound infection and defect of the nasal column mucous. The comprehensive treatment group had the most significant improvement in nasal length and nasal tip projection, and the nasolabial angle was the closest to 90°, which indicated the most effective nasal revision and aesthetic contour.

CONCLUSIONS

The adjuvant therapy combines autologous shuffling lipo-aspirated fat and manual mechanical stretch before revision rhinoplasty could effectively improve the surgical outcome and decrease the postoperative complications regarding severe nasal contractures.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Transplantation of hybrid adipose-derived stem cell sheet with autologous peritoneum: An in vivo feasibility study

Introduction

In regenerative medicine, cell sheet engineering has various advantages, including the retention of cells at the transplantation site for a longer period and the local delivery of growth factors and cytokines. Adipose-derived stem cell (ASC) is widely used owing to their various functions such as wound healing, immunomodulation, and nerve regeneration, in addition to their ability to differentiate into adipocytes, chondrocytes, and osteoblasts. ASC sheet generated using cell sheet engineering is considered effective in preventing anastomotic leakage, a serious postoperative complication in gastrointestinal surgery. However, the ASC sheet is too soft, thin, and brittle to handle with laparoscopic forceps during the operation. Therefore, we considered using the peritoneum, which is stiff and easy to collect while operating, as an alternative support. In this study, we explored the feasibility of using the peritoneum as a support for the precise transplantation of ASC sheets during surgery.

Methods

ASCs were isolated from the subcutaneous fat of the inguinal region of Sprague-Dawley (SD) transgenic rats expressing green fluorescent protein. ASCs were cultured until passage 3, seeded in temperature-responsive culture dishes, and the resulting ASC sheet was harvested at more than 80% confluency. Non-transgenic SD rats were used for transplant experiments. The wall peritoneum was harvested from SD rats following laparotomy, and hybrid adipose-derived stem cell (HASC) sheet was prepared by laminating the peritoneum with ASC sheet. The cell sheets were transplanted on the backs of SD rats following the incision. On post-transplantation days 3 and 7, the specimens were extracted. ASC and HASC sheets were then compared macroscopically and histopathologically.

Results

HASC sheet transplantation was macroscopically and histopathologically more effective than ASC sheet transplantation. The peritoneum provided sufficient stiffness as a support for precise transplantation.

Conclusion

The newly developed HASC sheet, which combine the advantages of ASC sheet with those of the peritoneum, could be more useful for clinical application than the ASC sheet alone.

Systematic review and meta-analysis of positive long-term effects after intra-articular administration of orthobiologic therapeutics in horses with naturally occurring osteoarthritis

Equine veterinarians face challenges in treating horses with osteoarthritic joint pain in routine veterinary practice. All common treatment options aim to reduce the clinical consequences of osteoarthritis (OA) characterized by persistent synovitis and progressive degradation of articular cartilage. A range of joint-associated cell types and extracellular matrices are involved in the not yet entirely understood chronic inflammatory process. Regeneration of articular tissues to re-establish joint hemostasis is the future perspective when fundamental healing of OA is the long-term goal. The use of intra-articular applied biologic therapeutics derived from blood or mesenchymal stroma cell (MSC) sources is nowadays a well-accepted treatment option. Although this group of therapeutics is not totally consistent due to the lack of clear definitions and compositions, they all share a potential regenerative effect on articular tissues as described in in vivo and in vitro studies. However, the current stage of science in regenerative medicine needs to be supported by clinical reports as in fact, in vitro studies as well as studies using induced OA models still represent a fragment of the complex pathomechanism of naturally occurring OA. This systemic review aims to determine the long-term effect of orthobiologic therapeutics in horses suffering naturally occurring OA. Thereby, a meta-analysis of randomized controlled trials (RCTs) is conducted to describe the efficiency and safety of intra-articular applied orthobiologics in terms of lameness reduction in the long-term. Using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines, thirteen studies met the inclusion criteria for the systemic review. Four of those studies have further been evaluated by the meta-analysis comparing the long-term effect in lameness reduction. Each study was examined for risk of bias. For data evaluation, a random-effects model was used, describing the overall outcome in a forest plot. The I² statistic was used to assess heterogeneity. Results indicate, that orthobiologic therapies represent an effective long-term and safe OA treatment option. Due to the inhomogeneity of included studies, no statements are provided addressing specific orthobiologic therapies, affected joints, OA stage and horse's intended use. Future clinical trials should follow standardized study designs to provide comparable data.

Hypoxic ASCs-derived Exosomes Attenuate Colitis by Regulating Macrophage Polarization via miR-216a-5p/HMGB1 Axis

BACKGROUND

Exosomes derived from mesenchymal stem cells have shown therapeutic effects for colitis. As a more clinically accessible resource, the therapeutic potential of exosomes from adipose-derived stem cells (ASCs) has not been fully elucidated, and whether hypoxia precondition could improve the therapeutic effect of ASC-derived exosomes in colitis remains elusive.

METHODS

In this study, exosomes were derived from ASCs under normoxia (NExos) and hypoxia (HExos) and were identified by detecting their morphology, size distribution, and exosome surface markers. The concentration of inflammation-related cytokines was detected by ELISA, and macrophage phenotype-related genes were determined by quantitative reverse transcription-polymerase chain reaction (qRT-PCR), western blot, and immunofluorescence. A miRNA microarray sequencing analysis was conducted to confirm the differentially expressed miRNAs. Dextran sulfate sodium-induced colitis was employed as an in vivo assay.

RESULTS

Administration of NExos alleviated inflammation by modulating the balance of macrophages both in cellular assays and in vivo experiments, and HExos showed higher therapeutic efficiency than NExos. The miR-216a-5p in HExos was significantly enriched and promoted macrophage M2 polarization through transfer to macrophages by exosomes. The miR-216a-5p was confirmed to target the 3'-UTR of HMGB1. Mechanistically, hypoxia-induced ASCs release miR-216a-5p in an exosomal way that induced macrophage M2 polarization by regulating the HMGB1/TLR4/NF-κB signaling pathway.

CONCLUSIONS

Exosomal miR-216a-5p released from hypoxia-prime ASCs showed higher therapeutic efficiency than NExos in experimental colitis by promoting the M2 macrophage phenotype, which indicated that hypoxia prime may represent a promising approach to optimizing the function of ASC-derived exosomes.

Adipose-Derived Stromal/Stem Cell Response to Tumors and Wounds: Evaluation of Patient Age

Tumors were characterized as nonhealing wounds by Virchow in 1858 and Dvorak in 1986. Since then, researchers have analyzed tumors from a new perspective. The parallels between tumorigenesis and physiological wound healing can provide a new framework for developing antitumor therapeutics. One commonality between tumors and wounds is the involvement of the stromal environment, particularly adipose stromal/stem cells (ASCs). ASCs exhibit dual functions, in which they stimulate tumor progression and assist in tissue repair and regeneration. Numerous studies have focused on the role of ASCs in cancer and wound healing, but none to date has linked age, cancer, and wound healing. Furthermore, very few studies have focused on the role of donor-specific characteristics of ASCs, such as age and their role in facilitating ASC behavior in cancer and wound healing. This review article is designed to provide important insights into the impact of donor age on ASC tumor and wound response and their role in facilitating ASC behavior in cancer and wound healing.

Comparison between Cancellous Trabecular and Cortical Specimens from Human Lumbar Spine Samples as an Alternative Source of Mesenchymal Stromal Cells

Due to their immunosuppressive potential and ability to differentiate into multiple musculoskeletal cell lineages, mesenchymal stromal cells (MSCs) became popular in clinical trials for the treatment of musculoskeletal disorders. The aim of this study was to isolate and characterize native populations of MSCs from human cortical and cancellous bone from the posterior elements of the lumbar spine and determine what source of MSCs yield better quality and quantity of cells to be potentially use for spinal fusion repair. We were able to show that MSCs from trabecular and cortical spine had the typical MSC morphology and expression markers; the ability to differentiate in adipocyte, chondrocyte, or osteoblast but they did not have a consistent pattern in the expression of the specific differentiation lineage genes. Moreover, MSCs from both sites demonstrated an immune suppression profile suggesting that these cells may have a more promising success in applications related to immunomodulation more than exploring their ability to drive osteogenesis to prevent nonunion in spine fusion procedures.

Potential Therapeutic Role of Mesenchymal-Derived Stem Cells as an Alternative Therapy to Combat COVID-19 through Cytokines Storm

Medical health systems continue to be challenged due to newly emerging COVID-19, and there is an urgent need for alternative approaches for treatment. An increasing number of clinical observations indicate cytokine storms to be associated with COVID-19 severity and also to be a significant cause of death among COVID-19 patients. Cytokine storm involves the extensive proliferative and hyperactive activity of T and macrophage cells and the overproduction of pro-inflammatory cytokines. Stem cells are the type of cell having self-renewal properties and giving rise to differentiated cells. Currently, stem cell therapy is an exciting and promising therapeutic approach that can treat several diseases that were considered incurable in the past. It may be possible to develop novel methods to treat various diseases by identifying stem cells’ growth and differentiation factors. Treatment with mesenchymal stem cells (MSCs) in medicine is anticipated to be highly effective. The present review article is organized to put forward the positive arguments and implications in support of mesenchymal stem cell therapy as an alternative therapy to cytokine storms, to combat COVID-19. Using the immunomodulatory potential of the MSCs, it is possible to fight against COVID-19 and counterbalance the cytokine storm.

The Progress of Stem Cell Therapy in Myocardial-Infarcted Heart Regeneration: Cell Sheet Technology

Various tissues, including the heart, cornea, bone, esophagus, bladder and liver, have been vascularized using the cell sheet technique. It overcomes the limitations of existing techniques by allowing small layers of the cell sheet to generate capillaries on their own, and it can also be used to vascularize tissue-engineered transplants. Cell sheets eliminate the need for traditional tissue engineering procedures such as isolated cell injections and scaffold-based technologies, which have limited applicability. While cell sheet engineering can eliminate many of the drawbacks, there are still a few challenges that need to be addressed. The number of cell sheets that can be layered without triggering core ischemia or hypoxia is limited. Even when scaffold-based technologies are disregarded, strategies to tackle this problem remain a substantial impediment to the efficient regeneration of thick, living three-dimensional cell sheets. In this review, we summarize the cell sheet technology in myocardial infarcted tissue regeneration.

ADSCs Promote Tenocyte Proliferation by Reducing the Methylation Level of lncRNA Morf4l1 in Tendon Injury

Objective: Tendons are the special connective tissue that connects bones to muscles and governs joint movement in response to loads passed by muscles. The healing of tendon injuries is still a challenge. In recent years, adipose-derived mesenchymal stem cells (ADSCs) have been increasingly used for tissue regeneration, but the underlying mechanism of tendon injury still remains unclear.

Methods: High-throughput sequencing was used to identify a novel lncRNA, whose expression was significantly decreased in injured tendon compared with normal tendon. Furthermore, pyrosequencing, nuclear-cytoplasmic separation, FISH assay and qRT-PCR analysis were used to verify the level of lncRNA methylation in the injured tenocytes. lncRNA was confirmed to promote the proliferation of tenocytes by flow cytometry, wound healing assay, qRT-PCR, and western blot, and the target gene of lncRNA was predicted and verified. To confirm that ADSCs could repair injured tendons, ADSCs and injured tenocytes were co-cultured in vitro, and ADSCs were injected into injured tendons in vitro, respectively.

Results: The lncRNA Morf4l1 promoter methylation in injured tendons led to down-regulation of its expression and inhibition of tenocyte proliferation. LncRNA Morf4l1 promoted the expression of TGF-β2 by targeting 3′U of miR-145-5p. After co-cultured ADSCs and injured tenocytes, the expression of lncRNA Morf4l1 was up-regulated, and the proliferation of injured tenocytes in vitro was promoted. The ADSCs were injected into the injured tendon to repair the injured tendon in vivo.

Conclusion: This study confirmed that ADSCs promoted tendon wound healing by reducing the methylation level of lncRNA Morf4l1.

Role and Function of Mesenchymal Stem Cells on Fibroblast in Cutaneous Wound Healing

Skin wounds often repair themselves completely over time; however, this is true only for healthy individuals. Although various studies are being conducted to improve wound-healing therapy outcomes, the mechanisms of wound healing and regeneration are not completely understood yet. In recent years, mesenchymal stem cells (MSCs) have been reported to contribute significantly to wound healing and regeneration. Understanding the function of MSCs will help to elucidate the fundamentals of wound healing. MSCs are multipotent stem cells that are used in regenerative medicine for their ability to self-renew and differentiate into bone, fat, and cartilage, with few ethical problems associated with cell harvesting. Additionally, they have anti-inflammatory and immunomodulatory properties and antifibrotic effects via paracrine signaling, and many studies have been conducted to use them to treat graft-versus-host disease, inflammatory bowel disease, and intractable cutaneous wounds. Many substances derived from MSCs are involved in the wound-healing process, and specific cascades and pathways have been elucidated. This review aims to explain the fundamental role of MSCs in wound healing and the effects of MSCs on fibroblasts.

Low-dose mesenchymal stem cell therapy for discogenic pain: safety and efficacy results from a 1-year feasibility study

Aim: To evaluate safety and efficacy of low dose autologous adipose-derived mesenchymal stem cells (ADMSCs) for treatment of disc degeneration resulting in low back pain (LBP). Methods: Nine participants with chronic LBP originating from single-level lumbar disc disease underwent intradiscal injection of 10 million ADMSCs with optional repetition after 6 months. Results: No unexpected or serious adverse events were recorded. Seven (78%) of participants reported reductions in pain 12 months after treatment. Five (56%) reported increased work capacity. Three (33%) reduced analgesic medication. Improvements in EQ-5D and Oswestry disability index results were observed. MRI demonstrated no further disc degeneration and improvements to annular fissures and disc protrusions. Conclusion: This study provides initial evidence of safety and efficacy of ADMSCs for discogenic LBP.

Efficiency assessment of irrigation as an alternative method for improving the regenerative potential of nonhealing wounds

The application of mesenchymal stem/stromal cells (MSC) in regenerative medicine offers hope for the effective treatment of incurable or difficult‐to‐heal diseases. However, it requires the development of unified protocols for both safe and efficient cell acquisition and clinical usage. The therapeutic effect of fat grafts (containing stem cells) in non‐healing wounds has been discussed in previous studies, although the application requires local or general anaesthesia. The treatment of MSC derived from adipose tissue (ASC) could be a less invasive method, and efficient delivery could lead to more favourable outcomes, which should encourage clinicians to use such therapeutic approaches more frequently. Therefore, the aim of this study was to optimise the methods of ASC isolation, culture and administration while maintaining their high survival, proliferation and colonisation potential. The ASC were isolated by an enzymatic method and were characterised according to International Society for Cellular Therapy and International Federation for Adipose Therapeutics and Science guidelines. To assess the opportunity to obtain a sufficient number of cells for transplantation, long‐term cell cultures in two oxygen concentrations (5% vs. 21%) were conducted. For these cultures, the population doubling time, the cumulative time for cell population doublings and the rate of cell senescence were estimated. In a developed and pre‐defined protocol, ASC can be efficiently cultured at physiological oxygen concentrations (5%), which leads to faster proliferation and slower cell senescence. Subsequently, to select the optimal and minimally invasive methods of ASC transplantation, direct cell application with an irrigator or with skin dressings was analysed. Our results confirmed that both the presented methods of cell application allow for the safe delivery of isolated ASC into wounds without losing their vitality. Cells propagated in the described conditions and applied in non‐invasive cell application (with an irrigation system and dressings) to treat chronic wounds can be a potential alternative or supplement to more invasive clinical approaches.

Infrapatellar fat pad adipose-derived stem cells co-cultured with articular chondrocytes from osteoarthritis patients exhibit increased chondrogenic gene expression

Aim

The variable results in clinical trials of adipose tissue-derived stem cells (ASCs) for chondral defects may be due to the different ex vivo culture conditions of the ASCs which are implanted to treat the lesions. We sought to determine the optimal in vitro chondrocyte co-culture condition that promotes infrapatellar fat pad-derived (IFPD) ASC chondrogenic gene expression in a novel co-culture combination.

Methods

In our study, we utilized an in vitro autologous co-culture of IFPD ASCs and articular chondrocytes derived from Kellgren–Lawrence Grade III/IV osteoarthritic human knee joints at ASC-to-chondrocyte seeding log ratios of 1:1, 10:1, and 100:1. Gene expression following in vitro co-culture was quantified by RT-qPCR with a panel comprising COL1A1, COL2A1, COL10A1, L-SOX5, SOX6, SOX9, ACAN, HSPG2, and COMP for chondrogenic gene expression.

Results

The chondrogenic gene expression profiles from co-cultures were greater than would be expected from an expression profile modeled from chondrocyte and ASC-only monocultures. Additionally, chondrogenic gene expression decreased with increasing ASC-to-chondrocyte seeding ratios.

Conclusions

These findings provide insight into the mechanisms underlying clinical ASC therapies and signifies that IFPD ASCs pre-conditioned by chondrocyte co-culture may have improved chondrogenic potential for cartilage repair. This model can help further understand IFPD ASCs in chondral and osteochondral repair and the chondrogenic pathways involved.

Exercise-induced piezoelectric stimulation for cartilage regeneration in rabbits

More than 32.5 million American adults suffer from osteoarthritis, and current treatments including pain medicines and anti-inflammatory drugs only alleviate symptoms but do not cure the disease. Here, we have demonstrated that a biodegradable piezoelectric poly(L-lactic acid) (PLLA) nanofiber scaffold under applied force or joint load could act as a battery-less electrical stimulator to promote chondrogenesis and cartilage regeneration. The PLLA scaffold under applied force or joint load generated a controllable piezoelectric charge, which promoted extracellular protein adsorption, facilitated cell migration or recruitment, induced endogenous TGF-β via calcium signaling pathway, and improved chondrogenesis and cartilage regeneration both in vitro and in vivo. Rabbits with critical-sized osteochondral defects receiving the piezoelectric scaffold and exercise treatment experienced hyaline-cartilage regeneration and completely healed cartilage with abundant chondrocytes and type II collagen after 1 to 2 months of exercise (2 to 3 months after surgery including 1 month of recovery before exercise), whereas rabbits treated with nonpiezoelectric scaffold and exercise treatment had unfilled defect and limited healing. The approach of combining biodegradable piezoelectric tissue scaffolds with controlled mechanical activation (via physical exercise) may therefore be useful for the treatment of osteoarthritis and is potentially applicable to regenerating other injured tissues.

ASC and SVF Cells Synergistically Induce Neovascularization in Ischemic Hindlimb Following Cotransplantation

Previously, we reported the angio-vasculogenic properties of human stromal vascular fraction (SVF) and adipose tissue-derived mesenchymal stem cells (ASCs). In this study, we investigated whether the combination of ASCs and SVF cells exhibited synergistic angiogenic properties. We conducted quantitative (q)RT-PCR, Matrigel plug, tube formation assays, and in vivo therapeutic assays using an ischemic hind limb mouse model. Immunohistochemical analysis was also conducted. qRT-PCR results revealed that FGF-2 was highly upregulated in ASCs compared with SVF, while PDGF-b and VEGF-A were highly upregulated in SVF. Conditioned medium from mixed cultures of ASCs and SVF (A+S) cells showed higher Matrigel tube formation and endothelial cell proliferation in vitro. A+S cell transplantation into ischemic mouse hind limbs strongly prevented limb loss and augmented blood perfusion compared with SVF cell transplantation. Transplanted A+S cells also showed high capillary density, cell proliferation, angiogenic cytokines, and anti-apoptotic potential in vivo compared with transplanted SVF. Our data indicate that A+S cell transplantation results in synergistic angiogenic therapeutic effects. Accordingly, A+S cell injection could be an alternative therapeutic strategy for treating ischemic diseases.

Anti-senescence ion-delivering nanocarrier for recovering therapeutic properties of long-term-cultured human adipose-derived stem cells

BACKGROUND

Human adipose-derived stem cells (hADSCs) have been used in various fields of tissue engineering because of their promising therapeutic efficacy. However, the stemness of hADSCs cannot be maintained for long durations, and their therapeutic cellular functions, such as paracrine factor secretion decrease during long-term cell culture. To facilitate the use of long-term-cultured hADSCs (L-ADSCs), we designed a novel therapeutic anti-senescence ion-delivering nanocarrier (AIN) that is capable of recovering the therapeutic properties of L-ADSCs. In the present study, we introduced a low-pH-responsive ion nanocarrier capable of delivering transition metal ions that can enhance angiogenic paracrine factor secretion from L-ADSCs. The AINs were delivered to L-ADSCs in an intracellular manner through endocytosis.

RESULTS

Low pH conditions within the endosomes induced the release of transition metal ions (Fe) into the L-ADSCs that in turn caused a mild elevation in the levels of reactive oxygen species (ROS). This mild elevation in ROS levels induced a downregulation of senescence-related gene expression and an upregulation of stemness-related gene expression. The angiogenic paracrine factor secretion from L-ADSCs was significantly enhanced, and this was evidenced by the observed therapeutic efficacy in response to treatment of a wound-closing mouse model with conditioned medium obtained from AIN-treated L-ADSCs that was similar to that observed in response to treatment with short-term-cultured adipose-derived stem cells.

CONCLUSIONS

This study suggests a novel method and strategy for cell-based tissue regeneration that can overcome the limitations of the low stemness and therapeutic efficacy of stem cells that occurs during long-term cell culture.

Skeletal Muscle Regeneration by the Exosomes of Adipose Tissue-Derived Mesenchymal Stem Cells

Profound skeletal muscle loss can lead to severe disability and cosmetic deformities. Mesenchymal stem cell (MSC)-derived exosomes have shown potential as an effective therapeutic tool for tissue regeneration. This study aimed to determine the regenerative capacity of MSC-derived exosomes for skeletal muscle regeneration. Exosomes were isolated from human adipose tissue-derived MSCs (AD-MSCs). The effects of MSC-derived exosomes on satellite cells were investigated using cell viability, relevant genes, and protein analyses. Moreover, NOD-SCID mice were used and randomly assigned to the healthy control (n = 4), muscle defect (n = 6), and muscle defect + exosome (n = 6) groups. Muscle defects were created using a biopsy punch on the quadriceps of the hind limb. Four weeks after the surgery, the quadriceps muscles were harvested, weighed, and histologically analyzed. MSC-derived exosome treatment increased the proliferation and expression of myocyte-related genes, and immunofluorescence analysis for myogenin revealed a similar trend. Histologically, MSC-derived exosome-treated mice showed relatively preserved shapes and sizes of the muscle bundles. Immunohistochemical staining revealed greater expression of myogenin and myoblast determination protein 1 in the MSC-derived exosome-treated group. These results indicate that exosomes extracted from AD-MSCs have the therapeutic potential for skeletal muscle regeneration.

Lipoaspirate processing for the treatment of knee osteoarthritis: a review of clinical evidences

The autologous lipoaspirate processing allows to obtain a tissue product to be transplanted for regenerative purposes in multiple pathological sites, such as the knee joint affected by osteoarthritic disease. Recently, multiple protocols and devices have been designed for lipoaspirate processing. These protocols and devices do not use enzymatic digestion and respect the principles of the so-called "minimal manipulation in a closed system". In this study, we performed a systematic review of the literature to identify studies in which osteoarthritis was treated by minimally manipulated intra-articular SVF injection and assessment of therapeutic response was reported. All bias scores were analyzed based on the Coleman methodology score modified by Kon et al. [27] and a subsequent linear classification system of articles was proposed. We identified 12 clinical trials in which clinical evaluations were performed inconsistently using different scales of analysis. All studies reported a significant decrease in the patient's symptomatic discomfort, with improvement in joint function and reduction in pain. Most studies do not reach a high-quality level on the linear scale based on the Coleman-Kon scores. Although the treatment of osteoarthritis of the knee with regenerative methods is undoubtedly of interest, being aimed at healing the disease, this study highlights that the trials are numerically limited, and qualitatively not optimal according to the Coleman-Kon score. Reasonably, greater standardization of devices protocols will be desirable in the future. The high clinical potential offered by these methods could be optimized for all patients.

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.

Effects mediated by the α7 nicotinic acetylcholine receptor on cell proliferation and migration in rat adipose-derived stem cells

Adipose-derived stem cells (ASCs) are an attractive source for regenerative medicine as they can be easily isolated, rapidly expandable in culture and show excellent in vitro differentiation potential. Acetylcholine (ACh), one of the main neurotransmitters in central and peripheral nervous systems, plays key roles in the control of several physiological processes also in non-neural tissues. As demonstrated in our previous studies, ACh can contribute to the rat ASCs physiology, negatively modulating ASCs proliferation and migration via M2 muscarinic receptor (mAChR) activation. In the present work we show that rat ASCs also express α7 nicotinic receptors (nAChRs). In particular, we have investigated the effects mediated by the selective activation of α7 nAChRs, which causes a reduction of ASC proliferation without affecting cell survival and morphology, and significantly promotes cell migration via upregulation of the CXCR4 expression. Interestingly, the activation of the α7 nAChR also upregulates the expression of M2 mAChR protein, indicating a cooperation between muscarinic and nicotinic receptors in the inhibition of ASC proliferation.

Exposure to small molecule cocktails allows induction of neural crest lineage cells from human adipose-derived mesenchymal stem cells

Neural crest cells (NCCs) are a promising source for cell therapy and regenerative medicine owing to their multipotency, self-renewability, and capability to secrete various trophic factors. However, isolating NCCs from adult organs is challenging, because NCCs are broadly distributed throughout the body. Hence, we attempted to directly induce NCCs from human adipose-derived mesenchymal stem cells (ADSCs), which can be isolated easily, using small molecule cocktails. We established a controlled induction protocol with two-step application of small molecule cocktails for 6 days. The induction efficiency was evaluated based on mRNA and protein expression of neural crest markers, such as nerve growth factor receptor (NGFR) and sex-determining region Y-box 10 (SOX10). We also found that various trophic factors were significantly upregulated following treatment with the small molecule cocktails. Therefore, we performed global profiling of cell surface makers and identified distinctly upregulated markers, including the neural crest-specific cell surface markers CD271 and CD57. These results indicate that our chemical treatment can direct human ADSCs to developing into the neural crest lineage. This offers a promising experimental platform to study human NCCs for applications in cell therapy and regenerative medicine.

Mesenchymal stem cell therapy combined with arthroscopic abrasion arthroplasty regenerates cartilage in patients with severe knee osteoarthritis: a case series

Aim: To evaluate the safety and efficacy of adipose-derived mesenchymal stem cell (ADMSC) therapy in combination with arthroscopic abrasion arthroplasty (AAA) in advanced knee osteoarthritis (OA). Materials & methods: 27 patients with Grade IV OA of the knee underwent AAA and ADMSC therapy (50 × 10⁶ ADMSCs at baseline and 6 months). Clinical outcome was assessed over 36 months. Structural change was determined using MRI. Results: Treatment was well tolerated with no serious adverse events. Clinically significant improvements in pain and function were observed. Reproducible hyaline-like cartilage regeneration was seen in all participants. Conclusion: ADMSC therapy combined with AAA in Grade IV OA results in reproducible pain, functional and structural improvements. This represents a joint preservation technique for patients with advanced OA of the knee. Trial registration number: ACTRN12617000638336.

Is There A Causal Relationship between Childhood Obesity and Acute Lymphoblastic Leukemia? A Review

Childhood obesity is a growing epidemic with numerous global health implications. Over the past few years, novel insights have emerged about the contribution of adult obesity to cancer risk, but the evidence base is far more limited in children. While pediatric patients with acute lymphoblastic leukemia (ALL) are at risk of obesity, it is unclear if there are potential causal mechanisms by which obesity leads to ALL development. This review explores the endocrine, metabolic and immune dysregulation triggered by obesity and its potential role in pediatric ALL's genesis. We describe possible mechanisms, including adipose tissue attraction and protection of lymphoblasts, and their impact on ALL chemotherapies' pharmacokinetics. We also explore the potential contribution of cytokines, growth factors, natural killer cells and adipose stem cells to ALL initiation and propagation. While there are no current definite causal links between obesity and ALL, critical questions persist as to whether the adipose tissue microenvironment and endocrine actions can play a causal role in childhood ALL, and there is a need for more research to address these questions.

Antioxidant and Biological Properties of Mesenchymal Cells Used for Therapy in Retinitis Pigmentosa

Both tissue repair and regeneration are a priority in regenerative medicine. Retinitis pigmentosa (RP), a complex retinal disease characterized by the progressive loss of impaired photoreceptors, is currently lacking effective therapies: this represents one of the greatest challenges in the field of ophthalmological research. Although this inherited retinal dystrophy is still an incurable genetic disease, the oxidative damage is an important pathogenetic element that may represent a viable target of therapy. In this review, we summarize the current neuroscientific evidence regarding the effectiveness of cell therapies in RP, especially those based on mesenchymal cells, and we focus on their therapeutic action: limitation of both oxidative stress and apoptotic processes triggered by the disease and promotion of cell survival. Cell therapy could therefore represent a feasible therapeutic option in RP.

Investigation of the effect of a time delay on the characteristics and survival of dental pulp stem cells from extracted teeth

OBJECTIVES

This study investigates the post-extraction storage period of human dental pulp stem cells (hDPSCs) for stem cell banking by investigating the viability, function, mineralization, and gene expression of hDPSCs isolated from extracted teeth after 1 h, 6 h and 24 h post-tooth extraction.

DESIGN

hDPSCs were extracted from the pulp of impacted third molar teeth after 1 h, 6 h, and 24 h after extraction. The mesenchymal stem cell (MSCs) properties of three groups of cells were analyzed using flow cytometry. Cell morphology and proliferation were analyzed using a light microscope and an MTT assay. The viability, function, mineralization, and gene expression of hDPSCs of 1 h, 6 h, and 24 h groups were also assessed.

RESULTS

The delayed harvesting of hDPSCs for 1, 6 or 24 h caused a 31 % reduction in mineral nodule formation and a reduction in the gene expression of osteocalcin (OCN) and vascular endothelial growth factor-alpha (VEGFA). However, the 1, 6 or 24 h, time delay had little effect on MTT cell proliferation, cell viability or morphology. The delayed of harvesting of hDPSCs for 1, 6 or 24 h also had little effect on the expression of MSCs positive (CD44, CD106, CD90) or negative surface markers (CD45 and CD11b).

CONCLUSIONS

Our results suggest that a 24 h delay in harvesting hDPSCs from extracted teeth can reduce their mineralization and gene activity but does not markedly reduce survival. Quicker hDPSCs harvesting is likely to yield more useful hDPSCs for experimentation and clinical treatment.

Adipose-derived mesenchymal stromal cells promote corneal wound healing by accelerating the clearance of neutrophils in cornea

The dome-shaped cornea is a transparent, non-vascularized, and epithelialized highly organized tissue. Physical and chemical injuries may trigger corneal wound healing (CWH) response and result in neovascularization that impairs the visual function. CWH involves not only migration, proliferation, and differentiation of the cells in different layers of cornea, but also the mobilization of immune cells. We demonstrated here that human adipose-derived mesenchymal stromal cells (ADSCs) could effectively inhibit neovascularization during ethanol-induced injury in mouse cornea. Importantly, we found that while neutrophils are essential for CWH, excessive and prolonged neutrophil retention during the granulation stage contributes to neovascularization. ADSCs were found to promote the clearance of neutrophils in the cornea during the granulation stage, likely via increasing the reverse transendothelial cell migration of CXCR4high neutrophils from cornea to the lung. Our results demonstrate that ADSCs are effective in treating CWH-induced neovascularization and modulation of neutrophil clearance could be novel strategies for better vision recovery after injury.

Mesenchymal stem cell surgery, rescue and regeneration in retinitis pigmentosa: clinical and rehabilitative prognostic aspects

Purpose:

To assess whether treatment with the Limoli Retinal Restoration Technique (LRRT) can be performed in patients with retinitis pigmentosa (RP), grafting the autologous cells in a deep scleral pocket above the choroid of each eye to exert their beneficial effect on the residual retinal cells.

Methods:

The patients were subjected to a complete ophthalmological examination, including best corrected visual acuity (BCVA), close-up visus measurements, spectral domain-optical coherence tomography (SD-OCT), microperimetry (MY), and electroretinography (ERG). Furthermore, the complete ophthalmological examination was carried out at baseline (T0) and at 6 months (T180) after surgery. The Shapiro–Wilk test was used to assess the normality of distribution of the investigated parameters. A mixed linear regression model was used to analyse the difference in all the studied parameters at T0 and T180, and to compare the mean change between the two groups. All statistical analyses were performed with STATA 14.0 (Collage Station, Texas, USA).

Results:

LRRT treatment was performed in 34 eyes of 25 RP patients recruited for the study. The eyes were classified in two groups on the basis of foveal thickness (FT) assessed by SD-OCT: 14 eyes in Group A (FT≤190μm) and the remaining 20 ones in Group B (FT > 190μm). Although it had not reached the statistical significance, Group B showed a better improvement in BCVA, residual close-up visus and sensitivity than Group A.

Conclusions:

Previous studies have described the role of LRRT in slowing down retinal degenerative diseases. Consequently, this surgical procedure could improve the clinical and rehabilitative prognostic parameters in RP patients. On the other hand, further clinical research and studies with longer follow-up will be needed to evaluate its efficacy.

Combined pre-conditioning with salidroside and hypoxia improves proliferation, migration and stress tolerance of adipose-derived stem cells

Oxidative stress after ischaemia impairs the function of transplanted stem cells. Increasing evidence has suggested that either salidroside (SAL) or hypoxia regulates growth of stem cells. However, the role of SAL in regulating function of hypoxia‐pre–conditioned stem cells remains elusive. Thus, this study aimed to determine the effect of SAL and hypoxia pre‐conditionings on the proliferation, migration and tolerance against oxidative stress in rat adipose‐derived stem cells (rASCs). rASCs treated with SAL under normoxia (20% O₂) or hypoxia (5% O₂) were analysed for the cell viability, proliferation, migration and resistance against H₂O₂‐induced oxidative stress. In addition, the activation of Akt, Erk1/2, LC3, NF‐κB and apoptosis‐associated pathways was assayed by Western blot. The results showed that SAL and hypoxia treatments synergistically enhanced the viability (fold) and proliferation of rASCs under non‐stressed conditions in association with increased autophagic flux and activation of Akt, Erk1/2 and LC3. H₂O₂‐induced oxidative stress, cytotoxicity, apoptosis, autophagic cell death and NF‐κB activation were inhibited by SAL or hypoxia, and further attenuated by the combined SAL and hypoxia pre‐treatment. The SAL and hypoxia pre‐treatment also enhanced the proliferation and migration of rASCs under oxidative stress in association with Akt and Erk1/2 activation; however, the combined pre‐treatment exhibited a more profound enhancement in the migration than proliferation. Our data suggest that SAL combined with hypoxia pre‐conditioning may enhance the therapeutic capacity of ASCs in post‐ischaemic repair.

Allogeneic adipose-derived stem cells promote ischemic muscle repair by inducing M2 macrophage polarization via the HIF-1α/IL-10 pathway

Adipose-derived mesenchymal stem cells (ASCs) are multipotent stromal cells that possess considerable therapeutic potential for tissue remodeling. However, their protective mechanism in critical limb ischemia has not been fully defined. After the occlusion of blood vessels, hypoxia becomes a prominent feature of the ischemic limb. This study investigated the immunomodulatory effect of ASCs on ischemic muscle repair and explored the specific mechanism. We found that the ability of RAW264.7 cells to migrate was impaired in hypoxia, whereas coculturing with ASCs could enhance the migration capacity. In addition, under hypoxic conditions, the paracrine effect of ASCs was enhanced and ASCs could induce RAW264.7 macrophages toward the anti-inflammatory M2 phenotype. We further demonstrated that ASCs-derived interleukin 10 (IL-10), mediated by hypoxia inducible factor-1α (HIF-1α), played a crucial role in the induction of M2 macrophages by activating the signal transducer and activator of transcription 3 (STAT3)/Arginase (Arg-1) pathway. Our in vivo experiments revealed that transplanted ASCs exhibited an immunomodulatory effect by recruiting macrophages to ischemic muscle and increasing the density of M2 macrophages. The transplantation of ASCs into ischemic limbs induced increased blood flow reperfusion and limb salvage rate, whereas the depletion of tissue macrophages or transplanting HIF-1α-silenced ASCs inhibited the therapeutic effect. These findings elucidated the critical role of macrophages in ASCs-mediated ischemic muscle repair and proved that allogeneic ASCs could exert the protective effect by enhancing the recruitment of macrophages and inducing macrophages toward M2 phenotype through HIF-1α/IL-10 pathway.

Evaluation of autologous adipose-derived mesenchymal stem cell therapy in focal chondral defects of the knee: a pilot case series

Aim: To evaluate the safety, pain, functional and structural improvements after autologous adipose-derived mesenchymal stem cell (ADMSC) therapy in combination with arthroscopic abrasion arthroplasty in focal chondral defects of the knee. Methods: Eight patients with a focal full thickness chondral defect of the knee underwent arthroscopic abrasion arthroplasty followed by postoperative intra-articular injections of autologous ADMSCs (50 × 10⁶ ADMSCs at baseline and 6 months). Clinical outcome was assessed using numeric pain rating scale, Knee Injury and Osteoarthritis Outcome Score and the Western Ontario and McMaster Universities Osteoarthritis Index. Structural outcome was determined by magnetic resonance imaging. Outcome was assessed over 24 months. Results: No serious adverse events occurred. Participants observed clinically significant improvement in pain and function. Magnetic resonance imaging analysis showed cartilage regeneration with T2 mapping values comparable to hyaline cartilage. Conclusion: Arthroscopic abrasion arthroplasty in combination with intra-articular ADMSC therapy results in reproducible pain, functional and structural improvements with regeneration of hyaline-like cartilage. Trial registration number: ACTRN12617000638336.

Fat graft for reducing pain in chronic wounds

BACKGROUND

Chronic wounds are one of the most important challenge for regenerative surgery. Plastic surgeon can use fat graft to increase wound healing because its growth factors can enhance tissue regeneration. In a recent study, the authors evaluated a reduction of pain in a cohort of patients submitted to breast reconstruction with breast implant and lipofilling, putting into evidence that growth factors in fat graft can reduce post-surgical pain. The aim of this work is to evaluate ultra-filtered fat graft potential in reducing pain in chronic wounds.

PATIENTS AND METHODS

Fifty new patients with chronic wounds of different etiology were recruited for this study and divided into two groups: A, treatment and B, control. Twenty-five patients per group. Negative pressure therapy dressing was applied after surgical debridement. Three days later patients in group A received ultrafiltered fat graft. Pain was evaluated with preoperative Visual Analogic Scale, repeated twice a day for 14 days and finally 21 days from procedures.

RESULTS

In group A (treated patients), pain was lower. These data were confirmed even after 7 days. The overall statistical analysis of the average of all values (SD 1.72) confirmed that the differences were significant at the 95% with the Chi-square test and analysis of variance (P value < .05).

CONCLUSIONS

The ultra-filtered fat graft placed on the wound bed and edges was effective in reducing pain in chronic wounds. The reduction of pain was statistically significant.

Therapeutic effect of adipose-derived mesenchymal stem cells (ASCs) on radiation-induced skin damage in rats

Background

Radiation-induced skin injury remains a serious concern, which may limit the duration and dose of radiation treatment. The concept that stem cell injection may reduce tissue injury or assist its recovery after radiation has been recently argued. Herein, we examined the effect of adipose-derived mesenchymal stem cells (ASCs) on radiation-induced skin damage in rats.

Methods

This study is an experimental case control study. ASCs were isolated from peri uterine fat tissue of the rats. Then the rats received a 30 Gy single dose radiation to their buttocks skin using gamma radiation. Next day stem cells were transplanted subcutaneously in 16 rats as the case group. A group of 16 rats was considered as control group with radiation but no transplantation of stem cells. Then rats were examined and observed by macroscopic analysis and phenotypic scores during 4 weeks of follow up.

Results

The wound size in control group was significantly higher than case group in the second, third and fourth weeks of evaluation (P<0.05). There was no significant difference in skin lesion severity, pathological factors, and the onset of recovery signs between two groups (P>0.05).

Conclusions

It seems that using ASCs alone has not profound effects on reducing radiation-induced cutaneous complications, while combination of these cells with growth factors may produce more promising results.

Cell Therapy for Ischemic Stroke: How to Turn a Promising Preclinical Research into a Successful Clinical Story

Stroke is a major public health issue with limited treatment. The pharmacologically or mechanically removing of the clot is accessible to less than 10% of the patients. Stem cell therapy is a promising alternative strategy since it increases the therapeutic time window but many issues remain unsolved. To avoid a new dramatic failure when translating experimental data on the bedside, this review aims to highlight the indispensable checkpoints to make a successful clinical trial based on the current preclinical literature. The large panel of progenitors/ stem cells at the researcher's disposal is to be used wisely, regarding the type of cells, the source of cells, the route of delivery, the time window, since it will directly affect the outcome. Mechanisms are still incompletely understood, although recent studies have focused on the inflammation modulation of most cells types.

Mesenchymal stem cell use in acute respiratory distress syndrome: a potential therapeutic application

Acute respiratory distress syndrome (ARDS) is a condition of acute respiratory failure resulting from noncardiogenic pulmonary edema. It may occur as a consequence of lung infection, sepsis, trauma, aspiration or drug reaction. The pathogenesis of ARDS is understood to be an unregulated inflammatory cascade with both endothelial and epithelial layer damage leading to alveolar fluid collection and pulmonary edema. Despite improved understanding of the cause of ARDS, treatment remains supportive with a mortality rate ranging from 25–40%. Preclinical and early phase clinical trials have highlighted the potential role of mesenchymal stem cells in combating the inflammatory cascade through immunomodulatory mechanisms and assisting in tissue repair.

Acute respiratory distress syndrome (ARDS) is a condition of sudden respiratory failure due to fluid in the lungs as a consequence of factors such as trauma and bacterial or viral lung infections. ARDS is understood to occur as a result of uncontrolled inflammation. Conventional treatment is supportive only with ARDS having a high death rate of up to 40%. Evidence from both preclinical and clinical trials highlight the potential role of mesenchymal stem cells in combating the inflammatory reactions that cause ARDS as this therapy both modifies the immune response and provides assistance with tissue repair.

Integrin β1 in Adipose-Derived Stem Cells Accelerates Wound Healing via Activating PI3K/AKT Pathway

BACKGROUND

This study aims to investigate the effect of integrin β1 on wound healing induced by adipose-derived stem cells (ADSCs), as well as the corresponding mechanism.

METHODS

Integrin β1 was overexpressed in ADSCs. Thereafter, flow cytometry and transwell chambers technology were used to measure the endothelial-like differentiation (CD31 as a biomarker of endothelial cell) and cell migration, respectively. Western blot was used to detect the activation of PI3K/AKT, NF-κB and ERK signaling pathways. The effects of integrin β1 overexpression on healing time, healing rate and fibroblast number were further evaluated in the rat models of chronic refractory wound.

RESULTS

The overexpression of integrin β1 increased CD31⁺ endothelial-like cells (about 3.6-fold), promoted cell migration (about 1.9-fold) and enhanced the activation of PI3K (p-PI3K; about 2.1-fold) and AKT (p-AKT; about 2.2-fold). These effects were all weakened when PI3K/AKT pathway was inhibited by LY294002 treatment. In addition, the experiments in rat wound models showed that integrin β1 overexpression obviously shortened healing time (approximately 0.41-fold), increased healing rate (about 2.7-fold, 2.8-fold and 1.6-fold at day 7, 14 and 21) and increased the number of fibroblasts (approximately 3.1-fold at day 21). All of the above differences were statistically significant (p < 0.05).

CONCLUSION

Integrin β1 can promote the migration and endothelial-like differentiation of ADSCs by activating PI3K/AKT pathway and then enhance the function of ADSCs in promoting wound healing.

Bone Tissue Regeneration in the Oral and Maxillofacial Region: A Review on the Application of Stem Cells and New Strategies to Improve Vascularization

Bone tissue engineering techniques are a promising alternative for the use of autologous bone grafts to reconstruct bone defects in the oral and maxillofacial region. However, for successful bone regeneration, adequate vascularization is a prerequisite. This review presents and discusses the application of stem cells and new strategies to improve vascularization, which may lead to feasible clinical applications. Multiple sources of stem cells have been investigated for bone tissue engineering. The stromal vascular fraction (SVF) of human adipose tissue is considered a promising single source for a heterogeneous population of essential cells with, amongst others, osteogenic and angiogenic potential. Enhanced vascularization of tissue-engineered grafts can be achieved by different mechanisms: vascular ingrowth directed from the surrounding host tissue to the implanted graft, vice versa, or concomitantly. Vascular ingrowth into the implanted graft can be enhanced by (i) optimizing the material properties of scaffolds and (ii) their bioactivation by incorporation of growth factors or cell seeding. Vascular ingrowth directed from the implanted graft towards the host tissue can be achieved by incorporating the graft with either (i) preformed microvascular networks or (ii) microvascular fragments (MF). The latter may have stimulating actions on both vascular ingrowth and outgrowth, since they contain angiogenic stem cells like SVF, as well as vascularized matrix fragments. Both adipose tissue-derived SVF and MF are cell sources with clinical feasibility due to their large quantities that can be harvested and applied in a one-step surgical procedure. During the past years, important advancements of stem cell application and vascularization in bone tissue regeneration have been made. The development of engineered in vitro 3D models mimicking the bone defect environment would facilitate new strategies in bone tissue engineering. Successful clinical application requires innovative future investigations enhancing vascularization.

Visfatin Mediates Malignant Behaviors through Adipose-Derived Stem Cells Intermediary in Breast Cancer

Adipose-derived stem cells (ADSCs) have been implicated in tumor growth and metastasis in breast cancer. ADSCs exhibit tumor tropism, and are of increasing clinical relevance due to the autologous fat grafting for breast reconstruction. Although we have previously shown that a high level of the adipocytokine visfatin in human breast cancer tissues correlated with tumor progression mediated by cAbl and STAT3, the effects of visfatin in the tumor microenvironment are unclear. To understand how visfatin modulates breast cancer within the tumor-stromal environment, we examined determinants of breast cancer progression using a visfatin-primed ADSCs-tumor co-culture model. ADSCs were isolated from tumor-free adipose tissue adjacent to breast tumors. ADSCs were treated with or without visfatin for 48 h and then collected for co-culture with breast cancer cell line MDA-MB-231 for 72 h in a transwell system. We found that the MDA-MB-231 cells co-cultured with visfatin-treated ADSCs (vADSCs) had higher levels of cell viability, anchorage independent growth, migration, invasion, and tumorsphere formation than that co-cultured with untreated ADSCs (uADSCs). Growth differentiation factor 15 (GDF15) upregulation was found in the co-culture conditioned medium, with GDF15 neutralizing antibody blocking the promoting effect on MDA-MB-231 in co-culture. In addition, a GDF15-induced AKT pathway was found in MDA-MB-231 and treatment with PI3K/AKT inhibitor also reversed the promoting effect. In an orthotopic xenograft mouse model, MDA-MB-231 co-injected with vADSCs formed a larger tumor mass than with uADSCs. Positive correlations were noted between visfatin, GDF15, and phosphor-AKT expressions in human breast cancer specimens. In conclusion, visfatin activated GDF15-AKT pathway mediated via ADSCs to facilitate breast cancer progression.

The Use of Allogenic Stromal Vascular Fraction (SVF) Cells in Degenerative Joint Disease of the Spine in Dogs

BACKGROUND/AIM

Stem cells are widely used in regenerative medicine and in clinical practice for the treatment of damaged nerve tissue, myocytes, tendons, and ligaments. The aim of the study was to monitor VEGF levels after the administration of allogenic cellular material (SVF) in the course of treatment of dogs suffering from degenerative joint disease in the spinal region.

MATERIALS AND METHODS

The study was conducted on 10 dogs of both genders, aged between 6 and 13 years in which allogenic stromal vascular fraction of stem cells (SVF) was administered intravenously. The control group was composed of 10 clinically healthy dogs. Before treatment and after 2- and 8-week intervals blood samples were obtained from the study group dogs in order to determine VEGF levels via immunoenzymatic test.

RESULTS

in a few days after the therapy, alleviation of pain symptoms and reduction of lameness were noticed. The VEGF level in 2 weeks after the therapy was significantly elevated (median: 38.77 pg/ml), while in 8 weeks a decrease was observed (median: 18.37 pg/ml). Conlusion: Administration of allogenic stem cells has a positive influence on elevation of the VEGF levels in the blood serum of affected animals as well as their regeneration capacity.

Adipose tissue grafting for management of persistent anastomotic leak after low anterior resection

BACKGROUND

An anastomotic leak is the most dreaded complication after low anterior resection. Adipose tissue grafting may induce healing in a persistent anastomotic defect. The aim of the present study was to report retrospectively reviewed outcomes for a series of patients who were managed with heterotopic grafted adipose tissue to facilitate anastomotic healing.

METHODS

Patients with anastomotic leakage after low anterior resection sequentially treated with grafting of adipose tissue were included in the study. All patients had pelvic radiation during treatment and had a diverting ileostomy in situ. The cohort had a persistent defect despite being treated with available modalities such as suture repair, fibrin glue, Endo-Sponge and surgical debridement. The outcomes were reviewed and reported.

RESULTS

There were 11 patients (8 males and 3 females) with a median age of 54 years (range 33-72 years). Five patients experienced complete healing of the anastomotic defect with successful reversal of the diverting ileostomy. The anastomotic defect of one other patient in the series appeared to have healed and hence his diverting ileostomy was reversed. However, he presented with a recurrent leak, which ultimately necessitated an abdominoperineal resection. Another patient had a persistent defect after an attempt at adipose tissue grafting and opted to proceed with a takedown of the anastomosis. In the remaining four patients, the outcome after adipose tissue grafting remains unknown, as two patients succumbed to metastatic disease, one was lost to follow-up and the remaining patient developed a recurrence which required pelvic exenteration. Procedural associated morbidity occurred in one patient who developed fat embolism, which was treated expectantly.

CONCLUSIONS

Adipose tissue grafting is safe and feasible, though its effectiveness remains uncertain. It may be useful selectively in the management of persistent anastomotic leak after radiation and low anterior resection.

Comparison of the proteome patterns of adipose-derived stem cells with those treated with selegiline using a two dimensional gel electrophoresis analysis

Adipose derived stem cells (ADSCs) are multipotent and can transdifferentiate into neural stem cells. We investigated the transdifferentiation of ADSCs to neural phenotype (NP) cells using selegiline and two-dimensional electrophoresis (2-DE). The perinephric and inguinal fat of rats was collected and used to isolate ADSCs that were characterized by immunophenotyping using flow cytometry. The ADSCs were differentiated into osteogenic and lipogenic cells. The NP cells were generated using 10^-9 mM selegiline and characterized by immunocytochemical staining of nestin and neurofilament 68 (NF-68), and by qRT-PCR of nestin, neurod1 and NF68. Total protein of ADSCs and NP cells was extracted and their proteome patterns were examined using 2-DE. ADSCs carried CD73, CD44 and CD90 cell markers, but not CD34. ADSCs were differentiated into osteocyte and adipocyte lineages. The differentiated NP cells expressed nestin, neuro d1 and NF-68. The proteome pattern of ADSCs was compared with that of NP cells and eight spots showed more than a two fold increase in protein expression. The molecular weights and isoelectric points of these highly expressed proteins were estimated using Melanie software. We compared these results with those of the mouse proteomic database using the protein isoelectric point database, and the functions of the eight proteins in differentiation of NP cells were predicted using the UniProt database. The probable identities of the proteins that showed higher expression in NP cells included cholinesterase, GFRa2, protein kinase C (PKC-eta) and RING finger protein 121. The sequences of the proteins identified from mouse database were aligned by comparing them with similar proteins in rat database using the Basic Local Alignment Search Tool (BLAST). The E values of all aligned proteins were zero, which indicates consistency of the matched protein. These proteins participate in differentiation of the neuron and their overexpression causes ADSCs transdifferentiation into NP cells.

Application of Cell Therapy for Anti-Aging Facial Skin

The human skin undergoes the complex process of aging which is prompted by the interplay of intrinsic mechanisms and extrinsic influences. Aging is unavoidable but can be somewhat delayed. Numerous approaches have been developed to slow down facial skin aging process as it is of interest to stake holders in the beauty and fashion world as well as to plastic surgeons. Adipose-derived stem cell [ADSC] and mesenchymal stem cell [MSC] as potential anti-aging agents to some extent have provided a promising and effective alternative in managing skin and facial skin aging. Furthermore, bone marrow-derived mesenchymal stem cells [BMMSC] have exhibited similar ability to rejuvenate aged skin. This review is aimed at giving a comprehensive account of the application of stem cells especially ADSCs and MSCs to reduce or slow down the rate of facial skin aging process.

Polyelectrolyte Complexes of Natural Polymers and Their Biomedical Applications

Polyelectrolyte complexes (PECs), composed of natural and biodegradable polymers, (such as positively charged chitosan or protamine and negatively charged glycosaminoglycans (GAGs)) have attracted attention as hydrogels, films, hydrocolloids, and nano-/micro-particles (N/MPs) for biomedical applications. This is due to their biocompatibility and biological activities. These PECs have been used as drug and cell delivery carriers, hemostats, wound dressings, tissue adhesives, and scaffolds for tissue engineering. In addition to their comprehensive review, this review describes our original studies and provides an overview of the characteristics of chitosan-based hydrogel, including photo-cross-linkable chitosan hydrogel and hydrocolloidal PECs, as well as molecular-weight heparin (LH)/positively charged protamine (P) N/MPs. These are generated by electrostatic interactions between negatively charged LH and positively charged P together with their potential biomedical applications.