Adipose-derived stromal cell in regenerative medicine:A review

The application of appropriate cell origin for utilizing inregenerative medicine is the major issue. Various kinds of stem cells have been used for the tissue engineering and regenerative medicine. Such as, several stromal cells have been employed as treat option for regenerative medicine. For example, human bone marrow-derived stromal cells and adipose-derived stromal cells(ADSCs) are used in cell-based therapy. Data relating to the stem cell therapy and processes associated with ADSC has developed remarkably in the past 10 years. As medical options, both the stromal vascular and ADSC suggests good opportunity as marvelous cell-based therapeutics. The some biological features are the main factors that impact the regenerative activity of ADSCs, including the modulation of the cellular immune system properties and secretion of bioactive proteins such as cytokines, chemokines and growth factors, as well as their intrinsic anti-ulcer and anti-inflammatory potential. A variety of diseases have been treated by ADSCs, and it is not surprising that there has been great interest in the possibility that ADSCs might be used as therapeutic strategy to improve a wider range of diseases. This is especially important when it is remembered that routine therapeutic methods are not completely effective in treat of diseases. Here, it was discuss about applications of ADSC to colitis, liver failure, diabetes mellitus, multiple sclerosis, orthopaedic disorders, hair loss, fertility problems, and salivary gland damage.

Apoptosis during β-mercaptoethanol-induced differentiation of adult adipose-derived stromal cells into neurons

β-mercaptoethanol can induce adipose-derived stromal cells to rapidly and efficiently differentiate into neurons in vitro.However,because of the short survival time of the differentiated cells,clinical applications for this technique are limited.As such,we examined apoptosis of neurons differentiated from adipose-derived stromal cells induced with β-mercaptoethanol in vitro using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling and transmission electron microscopy.The results revealed that the number of surviving cells decreased and apoptosis rate increased as induction time extended.Taken together,these results suggest that apoptosis occurring in the process of adipose-derived stromal cells differentiating into neurons is the main cause of cell death.However,the mechanism underlying cellular apoptosis should be researched further to develop methods of controlling apoptosis for clinical applications.

Ultrastructure of neuronal-like cells differentiated from adult adipose-derived stromal cells

β-mercaptoethanol induces in vitro adult adipose-derived stromal cells （ADSCs） to differentiate into neurons. However, the ultrastructural features of the differentiated neuronal-like cells remain unknown. In the present study, inverted phase contrast microscopy was utilized to observe β-mercaptoethanol-induced differentiation of neuronal-like cells from human ADSCs, and immunocytochemistry and real-time polymerase chain reaction were employed to detect expression of a neural stem cells marker （nestin）, a neuronal marker （neuron-specific enolase）, and a glial marker （glial fibrillary acidic protein）. In addition, ultrastructure of neuronal-like cells was observed by transmission election microscopy. Results revealed highest expression rate of nestin and neuron-specific enolase at 3 and 5 hours following induced differentiation; cells in the 5-hour induction group exhibited a neuronal-specific structure, i.e., Nissl bodies. However, when induction solution was replaced by complete culture medium after 8-hour induction, the differentiated cells reverted to the fibroblast-like morphology from day 1. These results demonstrate that β-mercaptoethanol-induced ADSCs induced differentiation into neural stem cells, followed by morphology of neuronal-like cells. However, this differentiation state was not stable.

A novel ethanol-based method to induce differentiation of adipose-derived stromal cells into astrocytes

The quantity and survival time of astrocytes,which were differentiated from adult adipose-derived stromal cells after exposure to an inducer containing 3-isobutyl-1-methylxanthine,have thus far been unsatisfactory.The present study investigated the growth and differentiation characteristics of induced astrocytes by observing their growth curves.After induction for 48 hours with an inducer containing 0.5% ethanol,some adult adult adipose-derived stromal cells displayed typical astrocytic morphology.The cell quantity gradually decreased with prolonged induction time.Nestin,glial fibrillary acidic protein,and S-100 expression reached peak levels at 14 days,but neuron-specific enolase was not expressed.These results suggest that the induced astrocytes reached their peak at 14 days.Further optimization of the culture environment may yield mature astrocytes with normal functions,in greater quantity,and prolonged survival time.

Adult adipose-derived stromal cells differentiate into neurons with normal electrophysiological functions

β-mercaptoethanol was used to induce in vitro neuronal differentiation of adipose-derived stromal cells. Within an 8-hour period post-differentiation, the induced cells exhibited typical neuronal morphology, and expression of microtubule-associated protein 2 and neuron-specific enolase, which are markers of mature neurons, reached a peak at 5 hours. Specific organelle Nissl bodies of neurons were observed under transmission electron microscopy. Results of membrane potential showed that fluorescence intensity of cells was greater after 5 hours than adipose-derived stromal cells prior to induction. In addition, following stimulation with high-concentration potassium solution, fluorescence intensity increased. These experimental findings suggested that neurons differentiated from adipose-derived stromal cells and expressed mature K^＋ channels. In addition, following stimulation with high potassium solution, the membrane potential depolarized and fired an action potential, confirming that the induced cells possessed electrophysiological functions.

Autophagy and apoptosis during adult adipose-derived stromal cells differentiation into neuron-like cells in vitro

β-mercaptoethanol can induce adult adipose-derived stromal cells to rapidly and efficiently differentiate into typical neuron-like cells in vitro. Immunohistochemistry showed that neuron specific enolase and neurofilament-200 expression gradually increased with the extension of induction time, and peaked at 5 hours. By contrast, glial fibrillary acidic protein was negatively expressed at all time points. Induced cells possessed a typical Nissl body, apoptosis showing condensed chromatin in the nucleus, autophagosomes with a bilayered membrane and autolysosomes in the cytoplasm at 5 hours. TUNEL assay and immunohistochemistry and immunofluorescence demonstrated that apoptosis and caspase-3 expression increased and peaked at 8 hours. Immunohistochemistry and immunofluorescence showed that microtubuleassociated protein light chain 3 gradually increased with induction and reached a peak at 5 hours These results indicate that autophagy played an important role in protecting cells during adult adipose-derived stromal cells differentiation into neuron-like cells in vitro.

Adipose-derived stromal cells resemble bone marrow stromal cells in hepatocyte differentiation potential in vitro and in vivo

AIM To investigate whether mesenchymal stem cells(MSCs) from adipose-derived stromal cells(ADSCs) and bone marrow stromal cells(BMSCs) have similar hepatic differentiation potential.METHODS Mouse ADSCs and BMSCs were isolated and cultured. Their morphological and phenotypic characteristics, as well as their multiple differentiation capacity were compared. A new culture system was established to induce ADSCs and BMSCs into functional hepatocytes. Reverse transcription polymerase chain reaction, Western blot, and immunofluorescence analyses were performed to identify the induced hepatocytelike cells. CM-Dil-labeled ADSCs and BMSCs were then transplanted into a mouse model of CCl4-induced acute liver failure. fluorescence microscopy was used to track the transplanted MSCs. Liver function was tested by an automatic biochemistry analyzer, and liver tissue histology was observed by hematoxylin and eosin(HE) staining.RESULTS ADSCs and BMSCs shared a similar morphology and multiple differentiation capacity, as well as a similar phenotype(with expression of CD29 and CD90 and no expression of CD11 b or CD45). Morphologically, ADSCs and BMSCs became round and epithelioid following hepatic induction. These two cell types differentiated into hepatocyte-like cells with similar expression of albumin, cytokeratin 18, cytokeratin 19, alpha fetoprotein, and cytochrome P450. fluorescence microscopy revealed that both ADSCs and BMSCs were observed in the mouse liver at different time points. Compared to the control group, both the function of the injured livers and HE staining showed significant improvement in the ADSC-and BMSC-transplanted mice. There was no significant difference between the two MSC groups.CONCLUSION ADSCs share a similar hepatic differentiation capacity and therapeutic effect with BMSCs in an acute liver failure model. ADSCs may represent an ideal seed cell type for cell transplantation or a bio-artificial liver support system.

Apoptosis is an obstacle to the differentiation of adipose-derived stromal cells into astrocytes

Previous studies have demonstrated that nerve cells differentiated from adipose-derived stro-mal cells after chemical induction have reduced viability;however, the underlying mechanisms remained unclear. In this study, we induced the differentiation of adult adipose-derived stromal cells into astrocytes using chemical induction. 3-（4,5-Dimethylthiazol-2-yl）-2,5-diphenyltetra-zolium bromide assay and flow cytometry showed that, with increasing induction time, the apoptotic rate gradually increased, and the number of living cells gradually decreased. Im-munohistochemical staining demonstrated that the number of glial fibrillary acidic protein-, caspase-3- and caspase-9-positive cells gradually increased with increasing induction time. Transmission electron microscopy revealed typical signs of apoptosis after differentiation. Taken together, our results indicate that caspase-dependent apoptosis is an obstacle to the differentia-tion of adipose-derived stromal cells into astrocytes. Inhibiting apoptosis may be an important strategy for increasing the efifciency of induction.

Induced Differentiation of Adipose-derived Stromal Cells into Myoblasts

This study aimed to induce the differentiation of isolated and purified adipose-derived stromal cells(ADSCs) into myoblasts,which may provide a new strategy for tissue engineering in patients with stress urinary incontinence(SUI).ADSCs,isolated and cultured ex vivo,were identified by flow cytometry and induced to differentiate into myoblasts in the presence of an induction solution consisting of DMEM supplemented with 5-azacytidine(5-aza),5% FBS,and 5% horse serum.Cellular morphology was observed under an inverted microscope.Ultrastructural changes occurring during the differentiation were observed by transmission electron microscopy and confocal laser scanning microscopy.Cellular immunohistochemical staining was applied to determine the expression of desmin protein in cells with and without induced differentiation.Reverse transcription-polymerase chain reaction(RT-PCR) and Western blotting were used to detect mRNA and protein expression,respectively,of sarcomeric and desmin smooth muscle proteins.The results showed that ADSCs were mainly of a spindle or polygon shape.Flow cytometry analysis revealed that ADSCs did not express CD34,CD45,and CD106 but high levels of CD44 and CD90,which confirmed that the cultured cells were indeed ADSCs.After induction with a 5-aza-containing solution,morphological changes in ADSCs,including irregular cell size,were observed.Cells gradually changed from long spindles to polygons and star-shaped cells with microvilli on the cell surface.Many organelles were observed and the cytoplasm was found to contain many mitochondria,rough endoplasmic reticulum(rER),and myofilament-like structures.Cell immunohistochemical staining revealed different levels of desmin expression in each phase of the induction process,with the highest expression level found on day 28 of induction.RT-PCR and Western blot results confirmed significantly higher desmin gene expression in induced cells compared with control cells,but no significant difference between the two groups of cells in sarcomeric protein expression.It was concluded that under specific induction setting,ADSCs can be induced to differentiate into myoblasts,providing a potential new option in stem cell transplantation therapy for SUI.

Adult adipose-derived stromal cells differentiating into neurons and neuron-like cells

Totally three articles regarding autophagy and apoptosis during differentiation of adult adipose-derived stromal cells into neurons and neuron-like cells were published in Neural Regeneration Research. We hope that our readers find these papers useful to their research.

Role of adipose-derived stromal cells in pedicle skin flap survival in experimental animal models

The use of skin flaps in reconstructive surgery is the first-line surgical treatment for the reconstruction of skin defects and is essentially considered the starting point of plastic surgery. Despite their excellent usability, their application includes general surgical risks or possible complications, the primary and most common is necrosis of the flap. To improve flap survival, researchers have used different methods, including the use of adiposederived stem cells, with significant positive results. In our research we will report the use of adipose-derived stem cells in pedicle skin flap survival based on current literature on various experimental models in animals.

Autophagy activator promotes neuronal differentiation of adult adipose-derived stromal cells

Preliminary research from our group found altered autophagy intensity during adipose-derived stromal cell differentiation into neuronal-like cells, and that this change was associated with morphological changes in differentiated cells. This study aimed to verify the role of rapamycin, an autophagy activator, in the process of adipose-derived stromal cell differentiation into neuronal-like cells. Immunohistochemical staining showed that expression of neuron-specific enolase and neurofilament-200 were gradually upregulated in adipose-derived stromal cells after 5 mM 13-mercaptoethanol induction, and the differentiation rate gradually increased with induction time. Using transmission electron microscopy, induced cells were shown to exhibit cytoplasmic autophagosomes, with bilayer membranes, and autolysosomes. After rapamycin （200 IJg/L） induction for 1 hour, adipose-derived stromal cells began to extend long processes, similar to the morphology of neuronal-like cells, while untreated cells did not exhibit similar morphologies until 3 hours after induction. Moreover, the differentiation rate was significantly increased after rapamycin treatment. Compared with untreated cells, expression of LC3, an autophagy protein, was also significantly upregulated. Positive LC3 expression tended to concentrate at cell nuclei with increasing induction times. Our experimental findings indicate that autophagy can significantly increase the speed of adipose-derived stromal cell differentiation into neuronal-like cells.

Intravenous administration of adipose-derived stromal cells does not ameliorate bleomycin-induced lung injury in rats

Background: Mesenchymal stromal cells (MSCs) have been studied intensively in regenerative medicine. Among MSCs, adipose tissue-derived stromal cells (ASCs) are relatively easy to obtain from a patient. Since ASCs are ideal candidates for use in the treatment of disease states including pulmonary fibrosis, we investigated whether intravenous injection of ASCs could exert a therapeutic effect against bleomycin-induced lung injury in rats. Methods: Rats were intratracheally administered bleomycin, and one week later ASCs were isolated and cultured. Two weeks after bleomycin treatment ASCs or PBS (phosphate-buffered saline) were injected to the rats. Three or six weeks after bleomycin instillation, the total cell counts and their profile in bronchoalveolar lavage fluid (BALF) were measured, and a histological evaluation was semi-quantitatively assessed for the injured lungs, followed by cell tracing. Results: The BALF cell counts and its profiles were not significantly different in the ASCs and PBS groups. Furthermore, ASC treatment led to no significant histological effect compared with the PBS treatment. Using a fluorescent cell tracer, it was noted that the ASCs homed to the injured lung areas, but some ASCs accumulated around scars, and scarcely migrated into the fibrotic areas. Conclusions: In the present study, the intravenous administration of ASCs could not reduce the severity of bleomycin-induced lung injury in a rat model. Although the ASC counts and passage numbers were suitable, the older age and fibrotic disease stage of the rats were likely responsible for the treatment failure.

Non-enzymatic methods for isolation of stromal vascular fraction and adipose-derived stem cells:A systematic review

BACKGROUND Adipose-derived stem cells(ADSCs)and the stromal vascular fraction(SVF)have garnered substantial interest in regenerative medicine due to their potential to treat a wide range of conditions.Traditional enzymatic methods for isolating these cells face challenges such as high costs,lengthy processing time,and regulatory complexities.AIM This systematic review aimed to assess the efficacy and practicality of nonenzymatic,mechanical methods for isolating SVF and ADSCs,comparing these to conventional enzymatic approaches.METHODS Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines,a comprehensive literature search was conducted across multiple databases.Studies were selected based on inclusion criteria focused on non-enzymatic isolation methods for SVF and ADSCs from adipose tissue.The risk of bias was assessed,and a qualitative synthesis of findings was performed due to the methodological heterogeneity of the included studies.RESULTS Nineteen studies met the inclusion criteria,highlighting various mechanical techniques such as centrifugation,vortexing,and ultrasonic cavitation.The review identified significant variability in cell yield and viability,and the integrity of isolated cells across different non-enzymatic methods compared to enzymatic procedures.Despite some advantages of mechanical methods,including reduced processing time and avoidance of enzymatic reagents,the evidence suggests a need for optimization to match the cell quality and therapeutic efficacy achievable with enzymatic isolation.CONCLUSION Non-enzymatic,mechanical methods offer a promising alternative to enzymatic isolation of SVF and ADSCs,potentially simplifying the isolation process and reducing regulatory hurdles.However,further research is necessary to standardize these techniques and ensure consistent,high-quality cell yields for clinical applications.The development of efficient,safe,and reproducible non-enzymatic isolation methods could significantly advance the field of regenerative medicine.

Photobiomodulation:a novel approach to promote trans-differentiation of adipose-derived stem cells into neuronal-like cells

Photobiomodulation,originally used red and near-infrared lasers,can alter cellular metabolism.It has been demonstrated that the visible spectrum at 451-540 nm does not necessarily increase cell proliferation,near-infrared light promotes adipose stem cell proliferation and affects adipose stem cell migration,which is necessary for the cells homing to the site of injury.In this in vitro study,we explored the potential of adipose-derived stem cells to differentiate into neurons for future translational regenerative treatments in neurodegenerative disorders and brain injuries.We investigated the effects of various biological and chemical inducers on trans-differentiation and evaluated the impact of photobiomodulation using 825 nm near-infrared and 525 nm green laser light at 5 J/cm2.As adipose-derived stem cells can be used in autologous grafting and photobiomodulation has been shown to have biostimulatory effects.Our findings reveal that adipose-derived stem cells can indeed trans-differentiate into neuronal cells when exposed to inducers,with pre-induced cells exhibiting higher rates of proliferation and trans-differentiation compared with the control group.Interestingly,green laser light stimulation led to notable morphological changes indicative of enhanced trans-differentiation,while near-infrared photobiomodulation notably increased the expression of neuronal markers.Through biochemical analysis and enzyme-linked immunosorbent assays,we observed marked improvements in viability,proliferation,membrane permeability,and mitochondrial membrane potential,as well as increased protein levels of neuron-specific enolase and ciliary neurotrophic factor.Overall,our results demonstrate the efficacy of photobiomodulation in enhancing the trans-differentiation ability of adipose-derived stem cells,offering promising prospects for their use in regenerative medicine for neurodegenerative disorders and brain injuries.

Immunomodulation of adipose-derived mesenchymal stem cells on peripheral blood mononuclear cells in colorectal cancer patients with COVID-19

BACKGROUND Accumulating evidence has shown that adipose tissue-derived mesenchymal stem cells(ADSCs)are an effective therapeutic approach for managing coronavirus disease 2019(COVID-19);however,further elucidation is required to determine their underlying immunomodulatory effect on the mRNA expression of T helper cell-related transcription factors(TFs)and cytokine release in peripheral blood mononuclear cells(PBMCs).AIM To investigate the impact of ADSCs on the mRNA expression of TFs and cytokine release in PBMCs from colorectal cancer(CRC)patients with severe COVID-19(CRC^(+)patients).METHODS PBMCs from CRC^(+)patients(PBMCs-C+)and age-matched CRC patients(PBMCs-C)were stimulated and cultured in the presence/absence of ADSCs.The mRNA levels of T-box TF TBX21(T-bet),GATA binding protein 3(GATA-3),RAR-related orphan receptor C(RORC),and forkhead box P3(FoxP3)in the PBMCs were determined by reverse transcriptase-polymerase chain reaction.Culture supernatants were evaluated for levels of interferon gamma(IFN-γ),interleukin 4(IL-4),IL-17A,and transforming growth factor beta 1(TGF-β1)using an enzyme-linked immunosorbent assay.RESULTS Compared with PBMCs-C,PBMCs-C+exhibited higher mRNA levels of T-bet and RORC,and increased levels of IFN-γ and IL-17A.Additionally,a significant decrease in FoxP3 mRNA and TGF-β1,as well as an increase in Tbet/GATA-3,RORC/FoxP3,IFN-γ/IL-4,and IL-17A/TGF-β1 ratios were observed in PBMCs-C+.Furthermore,ADSCs significantly induced a functional regulatory T cell(Treg)subset,as evidenced by an increase in FoxP3 mRNA and TGF-β1 release levels.This was accompanied by a significant decrease in the mRNA levels of T-bet and RORC,release of IFN-γ and IL-17A,and T-bet/GATA-3,RORC/FoxP3,IFN-γ/IL-4,and IL-17A/TGF-β1 ratios,compared with the PBMCs-C+alone.CONCLUSION The present in vitro studies showed that ADSCs contributed to the immunosuppressive effects on PBMCs-C+,favoring Treg responses.Thus,ADSC-based cell therapy could be a beneficial approach for patients with severe COVID-19 who fail to respond to conventional therapies.

Adipose-derived stem cells in diabetic foot care:Bridging clinical trials and practical application

Diabetic foot ulcers(DFUs)pose a critical medical challenge,significantly impairing the quality of life of patients.Adipose-derived stem cells(ADSCs)have been identified as a promising therapeutic approach for improving wound healing in DFUs.Despite extensive exploration of the mechanical aspects of ADSC therapy against DFU,its clinical applications remain elusive.In this review,we aimed to bridge this gap by evaluating the use and advancements of ADSCs in the clinical management of DFUs.The review begins with a discussion of the classification and clinical management of diabetic foot conditions.It then discusses the current landscape of clinical trials,focusing on their geographic distribution,reported efficacy,safety profiles,treatment timing,administration techniques,and dosing considerations.Finally,the review discusses the preclinical strategies to enhance ADSC efficacy.This review shows that many trials exhibit biases in study design,unclear inclusion criteria,and intervention protocols.In conclusion,this review underscores the potential of ADSCs in DFU treatment and emphasizes the critical need for further research and refinement of therapeutic approaches,with a focus on improving the quality of future clinical trials to enhance treatment outcomes and advance the field of diabetic wound care.

Etanercept-synthesizing adipose-derived stem cell secretome:A promising therapeutic option for inflammatory bowel disease

BACKGROUND Inflammatory bowel disease(IBD)is a chronic inflammatory condition of the gastrointestinal tract,with tumor necrosis factor(TNF)-αplaying a key role in its pathogenesis.Etanercept,a decoy receptor for TNF,is used to treat inflammatory conditions.The secretome derived from adipose-derived stem cells(ASCs)has anti-inflammatory effects,making it a promising therapeutic option for IBD.AIM To investigate the anti-inflammatory effects of the secretome obtained from ASCs synthesizing etanercept on colon cells and in a dextran sulfate sodium(DSS)-induced IBD mouse model.METHODS ASCs were transfected with etanercept-encoding mini-circle plasmids to create etanercept-producing cells.The secretory material from these cells was then tested for anti-inflammatory effects both in vitro and in a DSS-induced IBD mouse model.RESULTS This study revealed promising results indicating that the group treated with the secretome derived from etanercept-synthesizing ASCs[Etanercept-Secretome(Et-Sec)group]had significantly lower expression levels of inflammatory mediators,such as interleukin-6,Monocyte Chemoattractant Protein-1,and TNF-α,when compared to the control secretome(Ct-Sec).Moreover,the Et-Sec group exhibited a marked therapeutic effect in terms of preserving the architecture of intestinal tissue compared to the Ct-Sec.CONCLUSION These results suggest that the secretome derived from ASCs that synthesize etanercept has potential as a therapeutic agent for the treatment of IBD,potentially enhancing treatment efficacy by merging the anti-inflam-matory qualities of the ASC secretome with etanercept's targeted approach to better address the multifaceted pathophysiology of IBD.

Comparative effectiveness of adipose-derived mesenchymal stromal cells in the management of knee osteoarthritis:A meta-analysis

BACKGROUND Osteoarthritis(OA)is the most common joint disorder,is associated with an increasing socioeconomic impact owing to the ageing population.AIM To analyze and compare the efficacy and safety of bone-marrow-derived mesenchymal stromal cells(BM-MSCs)and adipose tissue-derived MSCs(AD-MSCs)in knee OA management from published randomized controlled trials(RCTs).METHODS Independent and duplicate electronic database searches were performed,including PubMed,EMBASE,Web of Science,and Cochrane Library,until August 2021 for RCTs that analyzed the efficacy and safety of AD-MSCs and BM-MSCs in the management of knee OA.The visual analog scale(VAS)score for pain,Western Ontario McMaster Universities Osteoarthritis Index(WOMAC),Lysholm score,Tegner score,magnetic resonance observation of cartilage repair tissue score,knee osteoarthritis outcome score(KOOS),and adverse events were analyzed.Analysis was performed on the R-platform using OpenMeta(Analyst)software.Twenty-one studies,involving 936 patients,were included.Only one study compared the two MSC sources without patient randomization;hence,the results of all included studies from both sources were pooled,and a comparative critical analysis was performed.RESULTS At six months,both AD-MSCs and BM-MSCs showed significant VAS improvement(P=0.015,P=0.012);this was inconsistent at 1 year for BM-MSCs(P<0.001,P=0.539),and AD-MSCs outperformed BM-MSCs compared to controls in measures such as WOMAC(P<0.001,P=0.541),Lysholm scores(P=0.006;P=0.933),and KOOS(P=0.002;P=0.012).BM-MSC-related procedures caused significant adverse events(P=0.003)compared to AD-MSCs(P=0.673).CONCLUSION Adipose tissue is superior to bone marrow because of its safety and consistent efficacy in improving pain and functional outcomes.Future trials are urgently warranted to validate our findings and reach a consensus on the ideal source of MSCs for managing knee OA.

Assessment of the effects of intrastromal injection of adipose-derived stem cells in keratoconus patients

·AIM: To evaluate the efficacy and safety of intrastromal transplantation of adipose-derived stem cells(ASCs) in keratoconus patients.·METHODS: This study was conducted on 8 eyes of 8 patients with moderate to severe keratoconus. In the patients, ophthalmic assessments including visual acuity, refraction, slit lamp examination, fundoscopy, corneal topography, and confocal microscopy were performed. Autologous stem cells were used. The isolated stem cells were injected into the corneal stroma by using femtosecond laser. Surgical procedure was similar to intracorneal ring implantation. All patients were re-assessed 1, 3, and 6mo after surgery.·RESULTS: The baseline mean visual acuity was 0.48±0.18 and improved to 0.66±0.17 after surger y and final acuity increased by 1.85±0.80 lines(P=0.001).The mean spherical refraction of patients improved 0.34 ± 0.35 D(P=0.039), and the mean cylindrical refraction of patients improved 0.84±0.23 D(P=0.016). The mean flat keratometry decreased 0.78±0.71 D(P=0.017), and the mean steep keratometry decreased 0.59±0.68 D(P=0.023). The mean central corneal thickness of patients improved of 6.29±4.47 μm(P=0.03). The mean keratocyte density at the anterior and middle stroma of cornea increased(P<0.05) but remained stable at the posterior stroma after 6mo. All patients had no complications and their corneas remained transparent. ·CONCLUSION: Intrastromal transplantation of ASCs has positive effects on vision and refractive parameters in most patients with keratoconus. After six months, visual acuity improved moderately, corneal parameters reduced slightly, and stromal keratocytes density increased. This modality is safe, and patients do not have any complications.