Transplantation of fibrin-thrombin encapsulated human induced neural stem cells promotes functional recovery of spinal cord injury rats through modulation of the microenvironment

Recent studies have mostly focused on engraftment of cells at the lesioned spinal cord,with the expectation that differentiated neurons facilitate recovery.Only a few studies have attempted to use transplanted cells and/or biomaterials as major modulators of the spinal cord injury microenvironment.Here,we aimed to investigate the role of microenvironment modulation by cell graft on functional recovery after spinal cord injury.Induced neural stem cells reprogrammed from human peripheral blood mononuclear cells,and/or thrombin plus fibrinogen,were transplanted into the lesion site of an immunosuppressed rat spinal cord injury model.Basso,Beattie and Bresnahan score,electrophysiological function,and immunofluorescence/histological analyses showed that transplantation facilitates motor and electrophysiological function,reduces lesion volume,and promotes axonal neurofilament expression at the lesion core.Examination of the graft and niche components revealed that although the graft only survived for a relatively short period(up to 15 days),it still had a crucial impact on the microenvironment.Altogether,induced neural stem cells and human fibrin reduced the number of infiltrated immune cells,biased microglia towards a regenerative M2 phenotype,and changed the cytokine expression profile at the lesion site.Graft-induced changes of the microenvironment during the acute and subacute stages might have disrupted the inflammatory cascade chain reactions,which may have exerted a long-term impact on the functional recovery of spinal cord injury rats.

Understanding host-graft crosstalk for predicting the outcome of stem cell transplantation

Mesenchymal stromal cells(MSCs)hold great promise for tissue regeneration in debilitating disorders.Despite reported improvements,the short-term outcomes of MSC transplantation,which is possibly linked to poor cell survival,demand extensive investigation.Disease-associated stress microenvironments further complicate outcomes.This debate underscores the need for a deeper understanding of the phenotypes of transplanted MSCs and their environment-induced fluctuations.Additionally,questions arise about how to predict,track,and comprehend cell fate post-transplantation.In vivo cellular imaging has emerged as a critical requirement for both short-and long-term safety and efficacy studies.However,translating preclinical imaging methods to clinical settings remains challenging.The fate and function of transplanted cells within the host environment present intricate challenges,including MSC engraftment,variability,and inconsistencies between preclinical and clinical data.The study explored the impact of high glucose concentrations on MSC survival in diabetic environments,emphasizing mitochondrial factors.Preserving these factors may enhance MSC survival,suggesting potential strategies involving genetic modification,biomaterials,and nanoparticles.Understanding stressors in diabetic patients is crucial for predicting the effects of MSC-based therapies.These multifaceted challenges call for a holistic approach involving the incorporation of large-scale data,computational disease modeling,and possibly artificial intelligence to enable deterministic insights.

Stem cell transplantation in cerebrovascular accidents:A global bibliometric analysis(2000-2023)

BACKGROUND Cerebrovascular accident(CVA)is a major global contributor to death and disability.As part of its medical management,researchers have recognized the importance of promising neuroprotective strategies,where stem cell transplantation(SCT)is thought to confer advantages via trophic and neuroprotective effects.AIM To evaluate the current state of research on SCT in patients with CVA,assess key trends and highlight literature gaps.METHODS PubMed was screened for SCT in CVA-related articles in October 2023,for each country during the period between 2000 and 2023.Using the World Bank data,total population and gross domestic product were collected for comparison.VOSviewer_1.6.19 was used to create the VOS figure using the results of the same query.Graphs and tables were obtained using Microsoft Office Excel.RESULTS A total of 6923 studies were identified on SCT in CVA,making 0.03%of all published studies worldwide.Approximately,68%were conducted in high-income countries,with a significant focus on mesenchymal stem cells.The journal“Stroke”featured the largest share of these articles,with mesenchymal SCT having the highest rate of inclusion,followed by hematopoietic SCT.Over time,there has been a noticeable shift from in vitro studies,which assess stem cell proliferation and neurogenesis,to in vivo studies aimed at evaluating efficacy and safety.Additionally,the number of reviews increased along this approach.CONCLUSION This bibliometric analysis provides a comprehensive guide for physicians and researchers in the field through an objective overview of research activity,and highlights both current trends and gaps.Having a potential therapeutic role in CVA,more research is needed in the future to focus on different aspects of SCT,aiming to reach a better treatment strategy and improve life quality in patients.

Quality-adjusted time without symptoms or toxicity analysis of haploidentical-related donor vs.identical sibling donor hematopoietic stem cell transplantation in acute myeloid leukemia

Objective:We aimed to compare the quality-adjusted time without symptoms or toxicity(Q-TWiST)in acute myeloid leukemia(AML)patients who received haploidentical-related donor(HID)and identical sibling donor(ISD)hematopoietic stem cell transplantation(HSCT).Methods:Five clinical health states were defined:toxicity(TOX),acute graft-versus-host disease(GVHD),chronic GVHD(cGVHD),time without symptoms and toxicity(TWiST)and relapse(REL).The equation used in this study was as follows:Q-TWiST=UTOX×TOX+UTWiST×TWiST+UREL×REL+UaGVHD×aGVHD+UcGVHD×cGVHD.Results:A total of 239 AML patients were enrolled.We established a mathematical model,i.e.,Q-TWiST HID HSCT>Q-TWiST ISD HSCT,to explore the range of utility coefficients satisfying the inequality.Based on the raw data,the utility coefficient is equivalent to the following inequality:10.57067UTOX-46.27733UREL+105.9374+3.388078UaGVHD-210.8198UcGVHD>0.The model showed that when UTOX,UREL,and UaGVHD were within the range of 0-1,as well as when UcGVHD was within the range of 0-0.569,the inequality Q-TWiST HID HSCT>Q-TWiST ISD HSCT was valid.According to the results of the ChiCTR1800016972 study,the median coefficients of TOX,acute GVHD(aGVHD),and cGVHD were 0.56(0.41-0.76),0.56(0.47-0.72),and 0.54(0.37-0.79),respectively.We selected a series of specific examples of the coefficients,i.e.,UTOX=0.5,UREL=0.05,UaGVHD-0.5,and UcGVHD-0.5.The Q-TWiST values of ISD and HID HSCT were 896 and 900 d,respectively(P=0.470).Conclusions:We first observed that Q-TWiST was comparable between AML patients receiving HID HSCT and those receiving ISD HSCT.

Long-term outcome of stem cell transplantation with and without anti-tumor necrotic factor therapy in perianal fistula with Crohn’s disease

BACKGROUND Stem cell transplantation is a promising therapeutic option for curing perianal fistula in Crohn’s disease(CD).Anti-tumor necrotic factor(TNF)therapy combined with drainage procedure is effective as well.However,previous studies are limited to proving whether the combination treatment of biologics and stem cell transplantation improves the effect of fistula closure.AIM This study aimed to evaluate the long-term outcomes of stem cell transplantation and compare Crohn’s perianal fistula(CPF)closure rates after stem cell transplantation with and without anti-TNF therapy,and to identify the factors affecting CPF closure and recurrence.METHODS The patients with CD who underwent stem cell transplantation for treating perianal fistula in our institution between Jun 2014 and December 2022 were enrolled.Clinical data were compared according to anti-TNF therapy and CPF closure.RESULTS A total of 65 patients were included.The median age of females was 26 years(range:21-31)and that of males was 29(44.6%).The mean follow-up duration was 65.88±32.65 months,and complete closure was observed in 50(76.9%)patients.The closure rates were similar after stem cell transplantation with and without anti-TNF therapy(66.7%vs 81.6%at 3 year,P=0.098).The patients with fistula closure had short fistulous tract and infrequent proctitis and anorectal stricture(P=0.027,0.002,and 0.008,respectively).Clinical factors such as complexity,number of fistulas,presence of concurrent abscess,and medication were not significant for closure.The cumulative 1-,2-,and 3-year closure rates were 66.2%,73.8%,and 75.4%,respectively.CONCLUSION Anti-TNF therapy does not increase CPF closure rates in patients with stem cell transplantation.However,both refractory and non-refractory CPF have similar closure rates after additional anti-TNF therapy.Fistulous tract length,proctitis,and anal stricture are risk factors for non-closure in patients with CPF after stem cell transplantation.

Advances in the treatment of autism spectrum disorder:Wharton jelly mesenchymal stem cell transplantation

BACKGROUND Autism spectrum disorder(ASD)is a complex neurodevelopmental disorder with multifaceted origins.In recent studies,neuroinflammation and immune dysregulation have come to the forefront in its pathogenesis.There are studies suggesting that stem cell therapy may be effective in the treatment of ASD.AIM To evolve the landscape of ASD treatment,focusing on the potential benefits and safety of stem cell transplantation.METHODS A detailed case report is presented,displaying the positive outcomes observed in a child who underwent intrathecal and intravenous Wharton’s jelly-derived mesenchymal stem cells(WJ-MSCs)transplantation combined with neurorehabilitation.RESULTS The study demonstrates a significant improvement in the child’s functional outcomes(Childhood Autism Rating Scale,Denver 2 Developmental Screening Test),especially in language and gross motor skills.No serious side effects were encountered during the 2-year follow-up.CONCLUSION The findings support the safety and effectiveness of WJ-MSC transplantation in managing ASD.

Controversies regarding transplantation of mesenchymal stem cells

Mesenchymal stem cells(MSCs)have tantalized regenerative medicine with their therapeutic potential,yet a cloud of controversies looms over their clinical tran-splantation.This comprehensive review navigates the intricate landscape of MSC controversies,drawing upon 15 years of clinical experience and research.We delve into the fundamental properties of MSCs,exploring their unique immuno-modulatory capabilities and surface markers.The heart of our inquiry lies in the controversial applications of MSC transplantation,including the perennial debate between autologous and allogeneic sources,concerns about efficacy,and lingering safety apprehensions.Moreover,we unravel the enigmatic mechanisms surro-unding MSC transplantation,such as homing,integration,and the delicate balance between differentiation and paracrine effects.We also assess the current status of clinical trials and the ever-evolving regulatory landscape.As we peer into the future,we examine emerging trends,envisioning personalized medicine and innovative delivery methods.Our review provides a balanced and informed perspective on the controversies,offering readers a clear understanding of the complexities,challenges,and potential solutions in MSC transplantation.

COVID-19 impact in Crohn’s disease patients submitted to autologous hematopoietic stem cell transplantation

BACKGROUND Severe acute respiratory syndrome coronavirus 2 is the virus responsible for coronavirus disease 2019(COVID-19),a disease that has been blamed for inducing or exacerbating symptoms in patients with autoimmune diseases.Crohn's disease(CD)is an inflammatory bowel disease that affects genetically susceptible patients who develop an abnormal mucosal immune response to the intestinal microbiota.Patients who underwent hematopoietic stem cell transplantation(HSCT)are considered at risk for COVID-19.AIM To describe for the first time the impact of COVID-19 in CD patients who had undergone autologous,non-myeloablative HSCT.METHODS In this descriptive study a series of 19 patients were diagnosed with positive COVID-19.For two patients there were reports of the occurrence of two infectious episodes.Parameters related to HSCT,such as time elapsed since the procedure,vaccination status,CD status before and after infection,and clinical manifestations resulting from COVID-19,were evaluated.RESULTS Among the patients with COVID-19,three,who underwent Auto HSCT less than six months ago,relapsed and one,in addition to the CD symptoms,started to present thyroid impairment with positive anti-TPO.Only one of the patients required hospitalization for five days to treat COVID-19 and remained in CD clinical remission.Nine patients reported late symptoms that may be related to COVID-19.There were no deaths,and a statistical evaluation of the series of COVID-19 patients compared to those who did not present any infectious episode did not identify significant differences regarding the analyzed parameters.CONCLUSION Despite the change in CD status in three patients and the presence of nine patients with late symptoms,we can conclude that there was no significant adverse impact concerning COVID-19 in the evaluated patients who underwent HSCT to treat CD.

Effects of mesenchymal stem cell on dopaminergic neurons,motor and memory functions in animal models of Parkinson's disease:a systematic review and meta-analysis

Parkinson’s disease is chara cterized by the loss of dopaminergic neurons in the substantia nigra pars com pacta,and although restoring striatal dopamine levels may improve symptoms,no treatment can cure or reve rse the disease itself.Stem cell therapy has a regenerative effect and is being actively studied as a candidate for the treatment of Parkinson’s disease.Mesenchymal stem cells are considered a promising option due to fewer ethical concerns,a lower risk of immune rejection,and a lower risk of teratogenicity.We performed a meta-analysis to evaluate the therapeutic effects of mesenchymal stem cells and their derivatives on motor function,memory,and preservation of dopamine rgic neurons in a Parkinson’s disease animal model.We searched bibliographic databases(PubMed/MEDLINE,Embase,CENTRAL,Scopus,and Web of Science)to identify articles and included only pee r-reviewed in vivo interve ntional animal studies published in any language through J une 28,2023.The study utilized the random-effect model to estimate the 95%confidence intervals(CI)of the standard mean differences(SMD)between the treatment and control groups.We use the systematic review center for laboratory animal expe rimentation’s risk of bias tool and the collaborative approach to meta-analysis and review of animal studies checklist for study quality assessment.A total of 33studies with data from 840 Parkinson’s disease model animals were included in the meta-analysis.Treatment with mesenchymal stem cells significantly improved motor function as assessed by the amphetamine-induced rotational test.Among the stem cell types,the bone marrow MSCs with neurotrophic factor group showed la rgest effect size(SMD[95%CI]=-6.21[-9.50 to-2.93],P=0.0001,I^(2)=0.0%).The stem cell treatment group had significantly more tyrosine hydroxylase positive dopamine rgic neurons in the striatum([95%CI]=1.04[0.59 to 1.49],P=0.0001,I^(2)=65.1%)and substantia nigra(SMD[95%CI]=1.38[0.89 to 1.87],P=0.0001,I^(2)=75.3%),indicating a protective effect on dopaminergic neurons.Subgroup analysis of the amphetamine-induced rotation test showed a significant reduction only in the intracranial-striatum route(SMD[95%CI]=-2.59[-3.25 to-1.94],P=0.0001,I^(2)=74.4%).The memory test showed significant improvement only in the intravenous route(SMD[95%CI]=4.80[1.84 to 7.76],P=0.027,I^(2)=79.6%).Mesenchymal stem cells have been shown to positively impact motor function and memory function and protect dopaminergic neurons in preclinical models of Parkinson’s disease.Further research is required to determine the optimal stem cell types,modifications,transplanted cell numbe rs,and delivery methods for these protocols.

Cell replacement with stem cell-derived retinal ganglion cells from different protocols

Glaucoma,characterized by a degenerative loss of retinal ganglion cells,is the second leading cause of blindness worldwide.There is currently no cure for vision loss in glaucoma because retinal ganglion cells do not regenerate and are not replaced after injury.Human stem cell-derived retinal ganglion cell transplant is a potential therapeutic strategy for retinal ganglion cell degenerative diseases.In this review,we first discuss a 2D protocol for retinal ganglion cell differentiation from human stem cell culture,including a rapid protocol that can generate retinal ganglion cells in less than two weeks and focus on their transplantation outcomes.Next,we discuss using 3D retinal organoids for retinal ganglion cell transplantation,comparing cell suspensions and clusters.This review provides insight into current knowledge on human stem cell-derived retinal ganglion cell differentiation and transplantation,with an impact on the field of regenerative medicine and especially retinal ganglion cell degenerative diseases such as glaucoma and other optic neuropathies.

Safety and efficiency of Wharton’s Jelly-derived mesenchymal stem cell administration in patients with traumatic brain injury:First results of a phase I study

BACKGROUND Traumatic brain injury(TBI)is characterized by a disruption in the normal function of the brain due to an injury following a trauma,which can potentially cause severe physical,cognitive,and emotional impairment.Stem cell transplantation has evolved as a novel treatment modality in the management of TBI,as it has the potential to arrest the degeneration and promote regeneration of new cells in the brain.Wharton’s Jelly-derived mesenchymal stem cells(WJ-MSCs)have recently shown beneficial effects in the functional recovery of neurological deficits.AIM To evaluate the safety and efficiency of MSC therapy in TBI.METHODS We present 6 patients,4 male and 2 female aged between 21 and 27 years who suffered a TBI.These 6 patients underwent 6 doses of intrathecal,intramuscular(i.m.)and intravenous transplantation of WJ-MSCs at a target dose of 1×106/kg for each application route.Spasticity was assessed using the Modified Ashworth scale(MAS),motor function according to the Medical Research Council Muscle Strength Scale,quality of life was assessed by the Functional Independence Measure(FIM)scale and Karnofsky Performance Status scale.RESULTS Our patients showed only early,transient complications,such as subfebrile fever,mild headache,and muscle pain due to i.m.injection,which resolved within 24 h.During the one year follow-up,no other safety issues or adverse events were reported.These 6 patients showed improvements in their cognitive abilities,muscle spasticity,muscle strength,performance scores and fine motor skills when compared before and after the intervention.MAS values,which we used to assess spasticity,were observed to statistically significantly decrease for both left and right sides(P<0.001).The FIM scale includes both motor scores(P<0.05)and cognitive scores(P<0.001)and showed a significant increase in pretest posttest analyses.The difference observed in the participants’Karnofsky Performance Scale values pre and post the intervention was statistically significant(P<0.001).CONCLUSION This study showed that cell transplantation has a safe,effective and promising future in the management of TBI.

Allogeneic mesenchymal stem cells may be a viable treatment modality in cerebral palsy

BACKGROUND Cerebral palsy(CP)describes a group of disorders affecting movement,balance,and posture.Disturbances in motor functions constitute the main body of CP symptoms.These symptoms surface in early childhood and patients are affected for the rest of their lives.Currently,treatment involves various pharmacotherapies for different types of CP,including antiepileptics for epilepsy and Botox A for focal spasticity.However,none of these methods can provide full symptom relief.This has prompted researchers to look for new treatment modalities,one of which is mesenchymal stem cell therapy(MSCT).Despite being a promising tool and offering a wide array of possibilities,mesenchymal stem cells(MSCs)still need to be investigated for their efficacy and safety.AIM To analyze the efficacy and safety of MSCT in CP patients.METHODS Our sample consists of four CP patients who cannot stand or walk without external support.All of these cases received allogeneic MSCT six times as 1×106/kg intrathecally,intravenously,and intramuscularly using umbilical cord-derived MSCs(UC-MSC).We monitored and assessed the patients pre-and post-treatment using the Wee Functional Independence Measure(WeeFIM),Gross Motor Function Classification System(GMFCS),and Manual Ability Classification Scale(MACS)instruments.We utilized the Modified Ashworth Scale(MAS)to measure spasticity.RESULTS We found significant improvements in MAS scores after the intervention on both sides.Two months:Rightχ^(2)=4000,P=0.046,leftχ^(2)=4000,P=0.046;four months:Rightχ^(2)=4000,P=0.046,leftχ^(2)=4000,P=0.046;12 months:Rightχ^(2)=4000,P=0.046,leftχ^(2)=4000,P=0.046.However,there was no significant difference in motor functions based on WeeFIM results(P>0.05).GMFCS and MACS scores differed significantly at 12 months after the intervention(P=0.046,P=0.046).Finally,there was no significant change in cognitive functions(P>0.05).CONCLUSION In light of our findings,we believe that UC-MSC therapy has a positive effect on spasticity,and it partially improves motor functions.

The Impact of Blood Transfusion on the Efficiency of Stem Cell Transplants

Background: While blood product transfusion is essential for managing hematologic deficits in Allogenic Hematopoietic stem cell transplant (AHSCT) recipients, it has risks including infectious disease transmission, alloimmunization, and transfusion reactions. These risks have sparked an ongoing debate regarding the overall impact of transfusions on patient outcomes. Thus, this study aimed to evaluate the impact of Red Blood Cells (RBCs) and/or platelet transfusion on the infection incidence and overall survival in AHSCT patients. Methods: We performed a retrospective analysis of clinical and laboratory data of sixty adult patients with primary malignant hematological disorder who had undergone AHSCT. Participants’ data were categorized into two groups;Group 1 (low transfusion group) consisted of patients receiving 10 units. Quantitative data were expressed as mean ± SD. The t-test of significance and Chi-square (χ2) test were used, with p ≤ 0.05 considered significant. Result: A total of 60 patients’ data was included. In Group 1, out of 30 patients, 13 (43.33%) developed infections. In contrast, Group 2 had 21 (70%) out of 30 patients develop infections. Group 1 had a higher survival rate (57.8%) than Group 2 (transfusion > 10 units) (46.2%) with a chi-square value = 23.56, and p-value Conclusion: The volume of blood product transfusions has a considerable impact on patient outcomes, particularly infection and survival rates. Additional long-term prospective studies and larger randomized controlled trials are needed to strengthen the evidence for determining transfusion protocols for these patients.

Development of Non-ABO Red Blood Cell Alloantibodies in Patient Undergoing Allogeneic Haematopoietic Stem Cell Transplant

Alloantibodies that are non ABO Alloimmunization to protein antigens happens only after exposure, in contrast to ABO isohaemagglutinins, which are present naturally, even in the absence of prior exposure. It is recognized that while non-ABO RBC antibodies are less common than ABO antibodies, they generate essentially the same issues that lead to unfavorable clinical results. If non-ABO alloantibodies are identified early on, these issues related complications may be avoided This call for an in-depth understanding of the recipient and donor’s ABO-Rh grouping, antibody screening, and the phenotype of certain antigens. Equally important, the temporal association time between transplantation and hemolysis can help identify the underlying mechanism of hemolysis and direct appropriate management. Therefore, for that, it is crucial to identify the etiology of post-HSCT anemia for prevention and therapy, in addition to a thorough grasp of the mechanism of anemia in non-ABO-incompatible HSCT and the temporal link between HSCT and anemia. Finding the cause of post-HSCT anemia is essential for prevention and therapy, in addition to a thorough grasp of the mechanism of anemia in non-ABO-incompatible HSCT and the temporal link between HSCT and anemia. Therefore, for that, it is crucial to identify the etiology of post-HSCT anemia. In this case report review, we would like to highlight the vital role of transfusion medicine services and stem cell clinical teams in paying particular attention to the clinical significance of non-ABO alloantibodies involved to avoid causing overt hemolysis of incompatible donor RBCs or delayed erythropoiesis. Considering the fact that some of the Haematopoietic stem cell transplant centers do not give an attention to the other non-ABO RBC antigens.

Overexpression of vascular endothelial growth factor enhances the neuroprotective effects of bone marrow mesenchymal stem cell transplantation in ischemic stroke

Although bone marrow mesenchymal stem cells(BMSCs)might have therapeutic potency in ischemic stroke,the benefits are limited.The current study investigated the effects of BMSCs engineered to overexpress vascular endothelial growth factor(VEGF)on behavioral defects in a rat model of transient cerebral ischemia,which was induced by middle cerebral artery occlusion.VEGF-BMSCs or control grafts were injected into the left striatum of the infarcted hemisphere 24 hours after stroke.We found that compared with the stroke-only group and the vehicle-and BMSCs-control groups,the VEGF-BMSCs treated animals displayed the largest benefits,as evidenced by attenuated behavioral defects and smaller infarct volume 7 days after stroke.Additionally,VEGF-BMSCs greatly inhibited destruction of the blood-brain barrier,increased the regeneration of blood vessels in the region of ischemic penumbra,and reducedneuronal degeneration surrounding the infarct core.Further mechanistic studies showed that among all transplant groups,VEGF-BMSCs transplantation induced the highest level of brain-derived neurotrophic factor.These results suggest that BMSCs transplantation with vascular endothelial growth factor has the potential to treat ischemic stroke with better results than are currently available.

Allogeneic stem cell transplantation in the treatment of acute myeloid leukemia: An overview of obstacles and opportunities

As an important treatment for acute myeloid leukemia, allogeneic hematopoietic stem cell transplantation(allo-HSCT) plays an important role in reducing relapse and improving long-term survival. With rapid advancements in basic research in molecular biology and immunology and with deepening understanding of the biological characteristics of hematopoietic stem cells, allo-HSCT has been widely applied in clinical practice. During allo-HSCT, preconditioning, the donor, and the source of stem cells can be tailored to the patient’s conditions, greatly broadening the indications for HSCT, with clear survival benefits. However, the risks associated with allo-HSCT remain high, i.e. hematopoietic reconstitution failure, delayed immune reconstitution, graft-versus-host disease, and posttransplant relapse, which are bottlenecks for further improvements in allo-HSCT efficacy and have become hot topics in the field of HSCT. Other bottlenecks recognized in the current treatment of individuals diagnosed with acute myeloid leukemia and subjected to allo-HSCT include the selection of the most appropriate conditioning regimen and post-transplantation management. In this paper, we reviewed the progress of relevant research regarding these aspects.

Sarcopenia and gut microbiota alterations in patients with hematological diseases before and after hematopoietic stem cell transplantation

Objective: The aim of this study was to investigate the prevalence of sarcopenia(SP) and its relationship with gut microbiota alterations in patients with hematological diseases before and after hematopoietic stem cell transplantation(HSCT).Methods: A total of 108 patients with various hematological disorders were selected from Peking University People’s Hospital. SP was screened and diagnosed based on the 2019 Asian Sarcopenia Diagnosis Strategy. Physical measurements and fecal samples were collected, and 16S rRNA gene sequencing was conducted. Alpha and beta diversity analyses were performed to evaluate gut microbiota composition and diversity.Results: After HSCT, significant decreases in calf circumference and body mass index(BMI) were observed,accompanied by a decline in physical function. Gut microbiota analyses revealed significant differences in the relative abundance of Enterococcus, Bacteroides, Blautia and Dorea species before and after HSCT(P<0.05). Before HSCT, sarcopenic patients had lower Dorea levels and higher Phascolarctobacterium levels than non-sarcopenia patients(P<0.01). After HSCT, no significant differences in species abundance were observed. Alpha diversity analysis showed significant differences in species diversity among the groups, with the highest diversity in the postHSCT 90-day group and the lowest in the post-HSCT 30-day group. Beta diversity analysis revealed significant differences in species composition between pre-and post-HSCT time points but not between SP groups. Linear discriminant analysis effect size(LEfSe) identified Alistipes, Rikenellaceae, Alistipes putredinis, Prevotellaceae defectiva and Blautia coccoides as biomarkers for the pre-HSCT sarcopenia group. Functional predictions showed significant differences in anaerobic, biofilm-forming and oxidative stress-tolerant functions among the groups(P<0.05).Conclusions: This study demonstrated a significant decline in physical function after HSCT and identified potential gut microbiota biomarkers and functional alterations associated with SP in patients with hematological disorders. Further research is needed to explore the underlying mechanisms and potential therapeutic targets.

Transplantation of human induced pluripotent stem cell derived keratinocytes accelerates deep second-degree burn wound healing

BACKGROUND Current evidence shows that human induced pluripotent stem cells(hiPSCs)can effectively differentiate into keratinocytes(KCs),but its effect on skin burn healing has not been reported.AIM To observe the effects of hiPSCs-derived KCs transplantation on skin burn healing in mice and to preliminarily reveal the underlying mechanisms.METHODS An analysis of differentially expressed genes in burn wounds based on GEO datasets GSE140926,and GSE27186 was established.A differentiation medium containing retinoic acid and bone morphogenetic protein 4 was applied to induce hiPSCs to differentiate into KCs.The expression of KCs marker proteins was detected using immunofluorescence staining.A model of a C57BL/6 mouse with deep cutaneous second-degree burn was created,and then phosphate buffered saline(PBS),hiPSCs-KCs,or hiPSCs-KCs with knockdown of COL7A1 were injected around the wound surface.The wound healing,re-epithelialization,engraftment of hiPSCs-KCs into wounds,proinflammatory factor level,and the NF-κB pathway proteins were assessed by hematoxylin-eosin staining,carboxifluorescein diacetate succinimidyl ester(CFSE)fluorescence staining,enzyme linked immunosorbent assay,and Western blotting on days 3,7,and 14 after the injection,respectively.Moreover,the effects of COL7A1 knockdown on the proliferation and migration of hiPSCs-KCs were confirmed by immunohistochemistry,EdU,Transwell,and damage repair assays.RESULTS HiPSCs-KCs could express the hallmark proteins of KCs.COL7A1 was down-regulated in burn wound tissues and highly expressed in hiPSCs-KCs.Transplantation of hiPSCs-KCs into mice with burn wounds resulted in a significant decrease in wound area,an increase in wound re-epithelialization,a decrease in proinflammatory factors content,and an inhibition of NF-κB pathway activation compared to the PBS group.The in vitro assay showed that COL7A1 knockdown could rescue the inhibition of hiPSCs-KCs proliferation and migration,providing further evidence that COL7A1 speeds up burn wound healing by limiting cell proliferation and migration.CONCLUSION In deep,second-degree burn wounds,COL7A1 can promote KC proliferation and migration while also suppressing the inflammatory response.

Focus on limbal stem cell deficiency and limbal cell transplantation

Limbal stem cell deficiency(LSCD)causes severe vision impairment and can lead to blindness,representing one of the most challenging ocular surface disorders.Stem cell deficiency can be congenital or,more often,acquired.The categorization of ocular surface transplantation techniques is crucial to achieving treatment homogeneity and quality of care,according to the anatomic source of the tissue being transplanted,genetic source,autologous or allogenic transplantation(to reflect histocompatibility in the latter group),and cell culture and tissue engineering techniques.The aim of this minireview is to provide a summary of the management of LSCD,from clinical characteristics and therapeutic outcomes to the development of novel therapeutic approaches.The manuscript also briefly summarizes recent findings in the current literature and outlines the future challenges to overcome in the management of the major types of ocular surface failure.

Human pluripotent stem cell-derivedβcells:Truly immature isletβcells for type 1 diabetes therapy?

A century has passed since the Nobel Prize winning discovery of insulin,which still remains the mainstay treatment for type 1 diabetes mellitus(T1DM)to this day.True to the words of its discoverer Sir Frederick Banting,“insulin is not a cure for diabetes,it is a treatment”,millions of people with T1DM are dependent on daily insulin medications for life.Clinical donor islet transplantation has proven that T1DM is curable,however due to profound shortages of donor islets,it is not a mainstream treatment option for T1DM.Human pluripotent stem cell derived insulin-secreting cells,pervasively known as stem cell-derivedβcells(SC-βcells),are a promising alternative source and have the potential to become a T1DM treatment through cell replacement therapy.Here we briefly review how isletβcells develop and mature in vivo and several types of reported SC-βcells produced using different ex vivo protocols in the last decade.Although some markers of maturation were expressed and glucose stimulated insulin secretion was shown,the SC-βcells have not been directly compared to their in vivo counterparts,generally have limited glucose response,and are not yet fully matured.Due to the presence of extra-pancreatic insulin-expressing cells,and ethical and technological issues,further clarification of the true nature of these SC-βcells is required.