Cell reprogramming therapy for Parkinson’s disease

Parkinson’s disease is typically characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta.Many studies have been performed based on the supplementation of lost dopaminergic neurons to treat Parkinson’s disease.The initial strategy for cell replacement therapy used human fetal ventral midbrain and human embryonic stem cells to treat Parkinson’s disease,which could substantially alleviate the symptoms of Parkinson’s disease in clinical practice.However,ethical issues and tumor formation were limitations of its clinical application.Induced pluripotent stem cells can be acquired without sacrificing human embryos,which eliminates the huge ethical barriers of human stem cell therapy.Another widely considered neuronal regeneration strategy is to directly reprogram fibroblasts and astrocytes into neurons,without the need for intermediate proliferation states,thus avoiding issues of immune rejection and tumor formation.Both induced pluripotent stem cells and direct reprogramming of lineage cells have shown promising results in the treatment of Parkinson’s disease.However,there are also ethical concerns and the risk of tumor formation that need to be addressed.This review highlights the current application status of cell reprogramming in the treatment of Parkinson’s disease,focusing on the use of induced pluripotent stem cells in cell replacement therapy,including preclinical animal models and progress in clinical research.The review also discusses the advancements in direct reprogramming of lineage cells in the treatment of Parkinson’s disease,as well as the controversy surrounding in vivo reprogramming.These findings suggest that cell reprogramming may hold great promise as a potential strategy for treating Parkinson’s disease.

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.

重组人糖蛋白激素β5/α2融合蛋白在CHO-S细胞中的表达纯化及功能活性分析

目的在悬浮中国仓鼠卵巢细胞(Chinese hamster ovary cells,CHO-S)中分泌表达、纯化重组hCGH-CTP融合蛋白,验证其对3T3-L1成熟脂肪细胞脂质积累的影响。方法构建CTP连接肽融合人糖蛋白激素β5/α2重组蛋白表达载体pcDNA3.1-rhCGH-CTP,将其瞬时转染CHO-S悬浮细胞中,大量表达纯化并验证rhCGH-CTP蛋白生物学活性;通过干预3T3-L1成熟脂肪细胞24 h,观察细胞内甘油三酯(TG)水平的变化。结果Western blot结果显示,rhCGH-CTP蛋白在CHO-S细胞中成功表达,表达量可达715.4 mg·L^(-1);用AKTA pure蛋白纯化系统纯化蛋白,SDS-PAGE方法鉴定纯化出的蛋白纯度较高可达90%。此外,在高表达TSHR基因的成熟脂肪细胞3T3-L1中,利用ELISA试剂盒测定不同浓度rhCGH-CTP蛋白干预后胞内cAMP含量明显升高,说明rhCGH-CTP蛋白具有生物活性;油红O染色结果发现,与对照组相比,不同浓度rhCGH-CTP蛋白干预组的成熟脂肪细胞中TG含量明显降低(P<0.05)。结论成功表达并纯化了rhCGH-CTP融合蛋白,其具有良好的生物学活性并能有效降低TG,该研究为后续深入揭示CGH蛋白的生理作用及在临床实践中的潜在应用提供了重要基础。

Neural stem cells promote neuroplasticity: a promising therapeutic strategy for the treatment of Alzheimer’s disease

Recent studies have demonstrated that neuroplasticity,such as synaptic plasticity and neurogenesis,exists throughout the normal lifespan but declines with age and is significantly impaired in individuals with Alzheimer’s disease.Hence,promoting neuroplasticity may represent an effective strategy with which Alzheimer’s disease can be alleviated.Due to their significant ability to self-renew,differentiate,and migrate,neural stem cells play an essential role in reversing synaptic and neuronal damage,reducing the pathology of Alzheimer’s disease,including amyloid-β,tau protein,and neuroinflammation,and secreting neurotrophic factors and growth factors that are related to plasticity.These events can promote synaptic plasticity and neurogenesis to repair the microenvironment of the mammalian brain.Consequently,neural stem cells are considered to represent a potential regenerative therapy with which to improve Alzheimer’s disease and other neurodegenerative diseases.In this review,we discuss how neural stem cells regulate neuroplasticity and optimize their effects to enhance their potential for treating Alzheimer’s disease in the clinic.

One-step cell biomanufacturing platform:porous gelatin microcarrier beads promote human embryonic stem cell-derived midbrain dopaminergic progenitor cell differentiation in vitro and survival after transplantation in vivo

Numerous studies have shown that cell replacement therapy can replenish lost cells and rebuild neural circuitry in animal models of Parkinson’s disease.Transplantation of midbrain dopaminergic progenitor cells is a promising treatment for Parkinson’s disease.However,transplanted cells can be injured by mechanical damage during handling and by changes in the transplantation niche.Here,we developed a one-step biomanufacturing platform that uses small-aperture gelatin microcarriers to produce beads carrying midbrain dopaminergic progenitor cells.These beads allow midbrain dopaminergic progenitor cell differentiation and cryopreservation without digestion,effectively maintaining axonal integrity in vitro.Importantly,midbrain dopaminergic progenitor cell bead grafts showed increased survival and only mild immunoreactivity in vivo compared with suspended midbrain dopaminergic progenitor cell grafts.Overall,our findings show that these midbrain dopaminergic progenitor cell beads enhance the effectiveness of neuronal cell transplantation.

Milk fat globule membrane supplementation protects againstβ-lactoglobul-ininduced food allergy in mice via upregulation of regulatory T cells and enhancement of intestinal barrier in a microbiota-derived short-chain fatty acids manner

Milk fat globule membrane(MFGM),which contains abundant glycoproteins and phospholipids,exerts beneficial effects on intestinal health and immunomodulation.The aim of this study was to evaluate the protective effects and possible underlying mechanisms of MFGM on cow’s milk allergy(CMA)in aβ-lactoglobulin(BLG)-induced allergic mice model.MFGM was supplemented to allergic mice induced by BLG at a dose of 400 mg/kg body weight.Results demonstrated that MFGM alleviated food allergy symptoms,decreased serum levels of lipopolysaccharide,pro-inflammatory cytokines,immunoglobulin(Ig)E,Ig G1,and Th2 cytokines including interleukin(IL)-4,while increased serum levels of Th1 cytokines including interferon-γand regulatory T cells(Tregs)cytokines including IL-10 and transforming growth factor-β.MFGM modulated gut microbiota and enhanced intestinal barrier of BLG-allergic mice,as evidenced by decreased relative abundance of Desulfobacterota,Rikenellaceae,Lachnospiraceae,and Desulfovibrionaceae,while increased relative abundance of Bacteroidetes,Lactobacillaceae and Muribaculaceae,and enhanced expressions of tight junction proteins including Occludin,Claudin-1 and zonula occludens-1.Furthermore,MFGM increased fecal short-chain fatty acids(SCFAs)levels,which elevated G protein-coupled receptor(GPR)43 and GPR109A expressions.The increased expressions of GPR43 and GPR109A induced CD103+dendritic cells accumulation and promoted Tregs differentiation in mesenteric lymph node to a certain extent.In summary,MFGM alleviated CMA in a BLG-induced allergic mice model through enhancing intestinal barrier and promoting Tregs differentiation,which may be correlated with SCFAs-mediated activation of GPRs.These findings suggest that MFGM may be useful as a promising functional ingredient against CMA.

Wharton’s jelly mesenchymal stem cells: Future regenerative medicine for clinical applications in mitigation of radiation injury

Wharton’s jelly mesenchymal stem cells(WJ-MSCs)are gaining significant attention in regenerative medicine for their potential to treat degenerative diseases and mitigate radiation injuries.WJ-MSCs are more naïve and have a better safety profile,making them suitable for both autologous and allogeneic transplantations.This review highlights the regenerative potential of WJ-MSCs and their clinical applications in mitigating various types of radiation injuries.In this review,we will also describe why WJ-MSCs will become one of the most probable stem cells for future regenerative medicine along with a balanced view on their strengths and weaknesses.Finally,the most updated literature related to both preclinical and clinical usage of WJ-MSCs for their potential application in the regeneration of tissues and organs will also be compiled.

Aqueous Extract of Ceiba pentandra Stimulates the Production of Fetal Hemoglobin in Sickle Cell Patients

Subsequent studies have demonstrated the reversed activity of the aqueous extract of Ceiba pentandra on the deformity of sickled red blood cells in hypoxia conditions. The observation which related to an in vitro study had given rise to hopes as to the management of sickle cell disease (SCD) by the use of this plant species. In this paper, the authors aimed to investigate the effect of the aqueous extract of C. pentandra on the production of fetal hemoglobin in SCD patients. The work carried out hemoglobin electrophoresis, for a period of six months, on blood samples from SCD patients who voluntarily undergone routine treatment, based on the medicinal recipe prepared from the bark of the trunk and branches of C. pentandra, in a hospital center of herbal medicines located in Kinshasa. The medicinal recipe called BEAT-SS is a patented product of the hospital center named Centre de Phytothérapie Moderne NIECA. Blood samples from patients under treatment were taken to evaluate the behavior of different forms of hemoglobin (hemoglobin S, hemoglobin F and hemoglobin A2). Agarose gel electrophoresis with integrated reading was used for the separation of the different forms of hemoglobin, as well as their dosage on each sample of sickle blood. A reduction in the proportion of hemoglobin S and an increase in the proportion of fetal hemoglobin were found in all sickle cell patients during the treatment period. This observation could affirm that the management of sickle cell patients using the recipe prepared from the aqueous extract of C. pentandra could increase the level of fetal hemoglobin in these patients.

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.

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.

Potential plausible role of Wharton’s jelly mesenchymal stem cells for diabetic bone regeneration

This letter addresses the review titled“Wharton’s jelly mesenchymal stem cells:Future regenerative medicine for clinical applications in mitigation of radiation injury”.The review highlights the regenerative potential of Wharton’s jelly mesenchymal stem cells(WJ-MSCs)and describes why WJ-MSCs will become one of the most probable stem cells for future regenerative medicine.The potential plausible role of WJ-MSCs for diabetic bone regeneration should be noticeable,which will provide a new strategy for improving bone regeneration under diabetic conditions.

Effect of substrate temperature and oxygen plasma treatment on the properties of magnetron-sputtered CdS for solar cell applications

Cadmium sulfide(CdS)is an n-type semiconductor with excellent electrical conductivity that is widely used as an electron transport material(ETM)in solar cells.At present,numerous methods for preparing CdS thin films have emerged,among which magnetron sputtering(MS)is one of the most commonly used vacuum techniques.For this type of technique,the substrate temperature is one of the key deposition parameters that affects the interfacial properties between the target film and substrate,determining the specific growth habits of the films.Herein,the effect of substrate temperature on the microstructure and electrical properties of magnetron-sputtered CdS(MS-CdS)films was studied and applied for the first time in hydrothermally deposited antimony selenosulfide(Sb_(2)(S,Se)_(3))solar cells.Adjusting the substrate temperature not only results in the design of the flat and dense film with enhanced crystallinity but also leads to the formation of an energy level arrangement with a Sb_(2)(S,Se)_(3)layer that is more favorable for electron transfer.In addition,we developed an oxygen plasma treatment for CdS,reducing the parasitic absorption of the device and resulting in an increase in the short-circuit current density of the solar cell.This study demonstrates the feasibility of MS-CdS in the fabrication of hydrothermal Sb_(2)(S,Se)_(3)solar cells and provides interface optimization strategies to improve device performance.

In-doping collaboratively controlling back interface and bulk defects to achieve efficient flexible CZTSSe solar cells

Focusing on the low open circuit voltage(V_(OC))and fill factor(FF)in flexible Cu_(2)ZnSn(S,Se)_(4)(CZTSSe)solar cells,indium(In)ions are introduced into the CZTSSe absorbers near Mo foils to modify the back interface and passivate deep level defects in CZTSSe bulk concurrently for improving the performance of flexible device.The results show that In doping effectively inhibits the formation of secondary phase(Cu(S,Se)_(2))and VSndefects.Further studies demonstrate that the barrier height at the back interface is decreased and the deep level defects(Cu_(Sn)defects)in CZTSSe bulk are passivated.Moreover,the carrier concentration is increased and the V_(OC) deficit(V_(OC,def))is decreased significantly due to In doping.Finally,the flexible CZTSSe solar cell with 10.01%power conversion efficiency(PCE)has been obtained.The synergistic strategy of interface modification and bulk defects passivation through In incorporation provides a new thought for the fabrication of efficient flexible kesterite-based solar cells.

Gamma-glutamyl transferase 5 overexpression in cerebrovascular endothelial cells improves brain pathology,cognition,and behavior in APP/PS1 mice

In patients with Alzheimer’s disease,gamma-glutamyl transferase 5(GGT5)expression has been observed to be downregulated in cerebrovascular endothelial cells.However,the functional role of GGT5 in the development of Alzheimer’s disease remains unclear.This study aimed to explore the effect of GGT5 on cognitive function and brain pathology in an APP/PS1 mouse model of Alzheimer’s disease,as well as the underlying mechanism.We observed a significant reduction in GGT5 expression in two in vitro models of Alzheimer’s disease(Aβ_(1-42)-treated hCMEC/D3 and bEnd.3 cells),as well as in the APP/PS1 mouse model.Additionally,injection of APP/PS1 mice with an adeno-associated virus encoding GGT5 enhanced hippocampal synaptic plasticity and mitigated cognitive deficits.Interestingly,increasing GGT5 expression in cerebrovascular endothelial cells reduced levels of both soluble and insoluble amyloid-βin the brains of APP/PS1 mice.This effect may be attributable to inhibition of the expression ofβ-site APP cleaving enzyme 1,which is mediated by nuclear factor-kappa B.Our findings demonstrate that GGT5 expression in cerebrovascular endothelial cells is inversely associated with Alzheimer’s disease pathogenesis,and that GGT5 upregulation mitigates cognitive deficits in APP/PS1 mice.These findings suggest that GGT5 expression in cerebrovascular endothelial cells is a potential therapeutic target and biomarker for Alzheimer’s disease.

稳定表达猪δ冠状病毒S1蛋白CHO细胞系的构建与鉴定

为构建稳定表达猪δ冠状病毒(PDCoV)S1蛋白的CHO细胞系,利用电转染技术将重组质粒pCGS3-S1转染至CHO细胞,通过有限稀释法筛选稳定表达重组S1蛋白的单克隆细胞系。利用阴离子交换层析和凝胶过滤层析方法对重组S1蛋白进行纯化,采用间接ELISA方法检测重组S1蛋白活性。将纯化的重组S1蛋白免疫BALB/c小鼠,通过间接ELISA、间接免疫荧光试验(IFA)及病毒中和试验对重组S1蛋白免疫原性进行检测。结果显示,稳定表达PDCoV S1蛋白的CHO细胞系成功建立,并获得了纯度高于90%、产量为28.5 mg/L的重组S1蛋白;且重组S1蛋白与PDCoV阳性血清反应性良好,具有良好的免疫原性,中和效价为1∶128。综上,成功建立了稳定表达PDCoV S1蛋白的CHO细胞系,且纯化获得的重组S1蛋白具有良好的生物学活性。

贝托司汀手性中间体(S)-CPMA整细胞催化合成工艺研究

针对不同条件对贝托司汀手性中间体(S)-CPMA的整细胞催化合成影响,进行单因素实验和正交设计优化研究.首先从耐热克鲁维酵母突变株SXBP-02预处理方式、不同催化反应介质、pH、底物质量浓度、温度、时间、催化剂用量、补料次数等8个方面进行考察,揭示其中pH、底物质量浓度、补料次数和催化剂用量4个因素对(S)-CPMA催化效率的影响较大;进一步对其进行正交优化,得出最佳工艺条件:在pH8的PEG4000双水相体系中,底物质量浓度为6g/L、补料次数为4次、催化剂用量为3g/L,温度为40℃条件下反应36h,可得到(S)-CPMA产率为88.1%,对映选择性在98.5%以上,4个因素对(S)-CPMA收率的影响主次顺序依次为补料次数>pH>催化剂用量>底物质量浓度,其中补料次数、pH为显著性影响因素,与优化前相比,底物质量浓度提高3倍,产率提高了6%.

帕金森病患者免疫球蛋白、Th9亚群水平变化及其与IGF-1、S-100B蛋白的相关性

目的:研究帕金森病(PD)患者免疫球蛋白(IgG、IgA和IgM)、辅助性T细胞亚群Th9水平变化及其与胰岛素生长因子-1(IGF-1)、S-100B蛋白的相关性。方法:选取2020年12月至2022年12月期间在河北省中医院确诊的108例PD患者,将其作为研究组,并根据患者病变程度分为轻度组(35例)、中度组(44例)和重度组(29例);另选108例健康成人作为对照组。对比研究组和对照组免疫球蛋白和Th9亚群水平,以及轻度组、中度组及重度组免疫球蛋白、Th9亚群、IGF-1和S-100B蛋白水平,采用Pearson相关性分析免疫球蛋白、Th9亚群和IGF-1、S-100B蛋白的相关性。采用Spearman相关性分析PD患者疾病程度和所有差异指标间的相关性。结果:研究组IgM水平较对照组低,且重度组低于中度组,中度组低于轻度组(P<0.05);研究组IgG、IgA、IL-9和Th9亚群水平较对照组高,且重度组高于中度组,中度组高于轻度组(P<0.05)。重度组IGF-1水平低于中度组,中度组低于轻度组;重度组S-100B蛋白水平高于中度组,中度组高于轻度组(P<0.05)。Pearson相关性分析结果显示,PD患者IgM水平与IGF-1水平呈正相关,与S-100B蛋白水平呈负相关;IgG、IgA、IL-9和Th9亚群水平均与IGF-1水平呈负相关,与S-100B蛋白水平呈正相关(P<0.05)。Spearman相关性分析结果显示,PD患者疾病程度与IgM、IGF-1水平呈负相关,与S-100B蛋白、IgG、IgA、IL-9和Th9亚群水平呈正相关(P<0.05)。结论:PD患者IgM水平降低,IgG、IgA、Th9亚群水平升高,且其水平变化与IGF-1、S-100B明显相关,可以用于评估病情的严重程度。

S-烯丙基巯基半胱氨酸促进CD8+T细胞杀伤功能的机制研究

目的探究S-烯丙基巯基半胱氨酸(S-allylmercaptocysteine,SAMC)对CD8^(+)T细胞杀伤鼻咽癌细胞功能的影响及机制。方法将人鼻咽癌细胞HK-1和C666-1与SAMC共培养,分为0、25、50、100μmol/L SAMC组,Western blot检测肿瘤细胞程序性死亡配体-1(programmed cell death-ligand 1,PD-L1)表达。CD8^(+)T细胞分别与HK-1和C666-1细胞以10∶1的比例共培养并加入0、25、50、100μmol/L SAMC,检测CD8^(+)T对HK-1和C666-1的杀伤能力,酶联免疫法(ELISA)检测干扰素(INF-γ)和肿瘤坏死因子-α(TNF-α)浓度,构建鼻咽细胞HK-1的小鼠皮下移植瘤模型,分为对照组、CD8^(+)T细胞组、SAMC组、SAMC+CD8^(+)T细胞组,各组小鼠治疗期间测量瘤体积,治疗结束后取小鼠肿瘤组织,Western blot检测肿瘤组织中PD-L1表达,ELISA检测小鼠血清INF-γ和TNF-α浓度。结果相比于0μmol/L SAMC组,25、50、100μmol/L SAMC组HK-1和C666-1细胞PD-L1表达均显著下调(P<0.05),相比于0μmol/L SAMC+CD8^(+)T细胞组,25、50、100μmol/L SAMC+CD8^(+)T细胞组HK-1和C666-1细胞培养上清中INF-γ和TNF-α浓度均能显著增加,HK-1和C666-1细胞裂解率显著增加(P<0.01)。相比于对照组,CD8^(+)T细胞组和SAMC+CD8^(+)T细胞组小鼠瘤体积和瘤重显著下降(P<0.05),小鼠血清INF-γ和TNF-α浓度显著增加,相比于CD8^(+)T细胞组,SAMC+CD8^(+)T细胞组小鼠瘤体积和瘤重显著下降(P<0.05),小鼠血清INF-γ和TNF-α浓度显著增加(P<0.05),肿瘤组织PD-L1表达显著下调(P<0.01)。结论SAMC可通过抑制人鼻咽癌细胞PD-L1表达而促进CD8^(+)T细胞的杀伤功能。

Neural progenitor cells derived from fibroblasts induced by small molecule compounds under hypoxia for treatment of Parkinson’s disease in rats

Neural progenitor cells(NPCs) capable of self-renewal and differentiation into neural cell lineages offer broad prospects for cell therapy for neurodegenerative diseases. However, cell therapy based on NPC transplantation is limited by the inability to acquire sufficient quantities of NPCs. Previous studies have found that a chemical cocktail of valproic acid, CHIR99021, and Repsox(VCR) promotes mouse fibroblasts to differentiate into NPCs under hypoxic conditions. Therefore, we used VCR(0.5 mM valproic acid, 3 μM CHIR99021, and 1 μM Repsox) to induce the reprogramming of rat embryonic fibroblasts into NPCs under a hypoxic condition(5%). These NPCs exhibited typical neurosphere-like structures that can express NPC markers, such as Nestin, SRY-box transcription factor 2, and paired box 6(Pax6), and could also differentiate into multiple types of functional neurons and astrocytes in vitro. They had similar gene expression profiles to those of rat brain-derived neural stem cells. Subsequently, the chemically-induced NPCs(ciNPCs) were stereotactically transplanted into the substantia nigra of 6-hydroxydopamine-lesioned parkinsonian rats. We found that the ciNPCs exhibited long-term survival, migrated long distances, and differentiated into multiple types of functional neurons and glial cells in vivo. Moreover, the parkinsonian behavioral defects of the parkinsonian model rats grafted with ciNPCs showed remarkable functional recovery. These findings suggest that rat fibroblasts can be directly transformed into NPCs using a chemical cocktail of VCR without introducing exogenous factors, which may be an attractive donor material for transplantation therapy for Parkinson’s disease.

Exosomes derived from human umbilical cord mesenchymal stem cells alleviate Parkinson’s disease and neuronal damage through inhibition of microglia

Microglia-mediated inflammatory responses have been shown to play a crucial role in Parkinson’s disease. In addition, exosomes derived from mesenchymal stem cells have shown anti-inflammatory effects in the treatment of a variety of diseases. However, whether they can protect neurons in Parkinson’s disease by inhibiting microglia-mediated inflammatory responses is not yet known. In this study, exosomes were isolated from human umbilical cord mesenchymal stem cells and injected into a 6-hydroxydopamine-induced rat model of Parkinson’s disease. We found that the exosomes injected through the tail vein and lateral ventricle were absorbed by dopaminergic neurons and microglia on the affected side of the brain, where they repaired nigral-striatal dopamine system damage and inhibited microglial activation. Furthermore, in an in vitro cell model, pretreating lipopolysaccharide-stimulated BV2 cells with exosomes reduced interleukin-1β and interleukin-18 secretion, prevented the adoption of pyroptosis-associated morphology by BV2 cells, and increased the survival rate of SH-SY5Y cells. Potential targets for treatment with human umbilical cord mesenchymal stem cells and exosomes were further identified by high-throughput microRNA sequencing and protein spectrum sequencing. Our findings suggest that human umbilical cord mesenchymal stem cells and exosomes are a potential treatment for Parkinson’s disease, and that their neuroprotective effects may be mediated by inhibition of excessive microglial proliferation.