血小板裂解物支持人骨髓基质细胞的扩增

目的探讨血小板裂解物体外培养、扩增人骨髓基质干细胞的可行性。方法将富含血小板血浆以冻融裂解法处理,培养人骨髓基质干细胞;体系中加入不同浓度的裂解物,MTT法检测细胞体外增殖情况;流式细胞仪分析细胞表型特征,并应用细胞化学染色法观察细胞体外成骨和成脂肪能力。结果血小板裂解物培养的骨髓基质干细胞呈典型的成纤维细胞形态,均一呈现CD14、CD31、CD34、CD45及HLA-DR阴性和CD73、CD90、CD105、CD166阳性,具备体外成骨、成脂分化能力。此外,与经筛选的胎牛血清比较,低浓度血小板裂解物即具有支持骨髓基质干细胞扩增的能力。结论血小板裂解物可替代胎牛血清,用于骨髓基质干细胞的体外扩增。     

帕米膦酸二钠对人骨髓间充质干细胞增殖和成骨分化的影响

目的观察帕米膦酸二钠对人骨髓间充质干细胞(Mesenchymal stem cells,MSC)生物学特性的影响,以探索双磷酸盐导致骨组织损伤的机制。方法人骨髓MSC培养体系中加入不同浓度的帕米膦酸二钠,培养72 h后,MTT法测定490 nm光密度值,观察细胞增殖情况;培养1周后,流式细胞技术检测细胞表面分子表达。体外诱导MSC成骨分化,体系中加入1μg/mL帕米膦酸二钠,1周后PCR法测定细胞Runx-2表达水平,2周后组织化学法测定细胞内碱性磷酸酶活性,以细胞总蛋白量为参照,观察MSC成骨分化的差异。结果 MTT结果显示,在0.1~10μg/mL浓度范围内,帕米膦酸二钠抑制人骨髓MSC增殖,作用呈浓度依赖性,最低作用浓度为1μg/mL,72 h OD490显著低于对照组(P<0.01)。流式细胞检测显示,帕米膦酸二钠处理后,细胞仍均一表达CD44和CD73,不表达CD31和CD45。PCR及细胞化学结果显示,帕米膦酸二钠无促进MSC成骨分化作用,也未提高成骨诱导体系促分化效果。结论帕米膦酸二钠可抑制MSC增殖,不促进其体外成骨能力,可能是长期使用双磷酸盐导致骨损伤的机制之一。     

同种异体血清在体外培养骨髓间充质干细胞的作用研究

[目的]适当的血清浓度可维持骨髓间充质干细胞(MSCs)的体外培养,血清浓度过低不利于细胞的生长,而高浓度血清则易引起细胞分化。而血清的不同来源对MSCs的培养同样产生影响。传统的培养方法用胎牛血清作为营养支持,临床应用时存在潜在的风险。本研究探讨同种异体血清在体外培养人骨髓间充质干细胞(hBM-SCs)的可行性。[方法]无菌条件下收集人骨髓悬液,分离hBMSCs,分别用含胎牛血清和人血清的培养基培养。分别测定2种方法培养的hBMSCs细胞生长曲线;采用流式细胞仪检测分析培养的hBMSCs表面抗原类型;并将培养的hBMSCs诱导分化为软骨细胞及神经细胞,诱导后的软骨细胞及神经细胞采用免疫组化染色分析。[结果]2种方法培养的间充质干细胞表面抗原CD29、CD44、CD105阳性,CD34、CD45、CD106以及HLA-DR阴性,表达强度无显著性差异;人血清培养的hBMSCs细胞生长速度快于胎牛血清培养组,但分化效率低于后者。[结论]通过生长特性、表面抗原表达以及分化潜能等方面的对比研究,人血清培养hBMSCs与胎牛血清培养差别不大,可以作为一种适合临床的安全培养方法。     

骨髓脂肪细胞多向分化潜能的初步探讨

目的 从人骨髓脂肪层中分离培养骨髓脂肪细胞,探讨其多向分化潜能.方法 体外贴壁培养和扩增人骨髓脂肪细胞,采用流式细胞仪检测骨髓脂肪细胞表面抗原CD105、CD166、CD49d等的表达情况.通过RT-PCR检测转录因子过氧化物酶增殖激活受体-γ2(PPAR-γ2)、CCAATT增强结合蛋白(C/EBPs)和瘦素(leptin)的表达.经体外诱导分化检测骨髓脂肪细胞的体外成脂和成骨能力.结果 流式细胞仪检测结果显示骨髓脂肪细胞与骨髓基质细胞具有相似的表面标志,但骨髓脂肪细胞特征性表达CD49d、C/EBPs以及leptin.体外诱导分化实验显示骨髓脂肪细胞具有成骨和成脂的能力.结论 骨髓脂肪细胞具有脂肪前体细胞的特性,但同时它具有同骨髓基质细胞相似的表面标志和多向分化潜能,提示可以作为一种新的组织工程种子细胞来源.     

体外诱导骨髓间充质干细胞向肾小管上皮样细胞分化

目的 观察不同条件下骨髓间充质干细胞（MSC）体外诱导分化为肾小管上皮样细胞的差异。 方法 抽取SD大鼠的骨髓,经密度梯度离心分离,联合贴壁筛选法获取纯化的MSC。以流式细胞仪鉴定间充质干细胞表面标志。取扩增3代的MSC分组培养：（1）对照组：用含胎牛血清培养基;（2）全反式维甲酸（ATRA）组：胎牛血清+缺血再灌注肾脏匀浆上清+ATRA;（3）联合诱导组：胎牛血清+缺血再灌注肾脏匀浆上清+ATRA+表皮生长因子（EGF）+骨形成蛋白（BMP-7）。诱导7 d后,倒置显微镜下观察细胞形态变化;化学染色检测细胞碱性磷酸酶表达;免疫细胞化学法检测细胞角蛋白18（cytokeratin-18）、E钙黏蛋白(E-cadherin)的表达。 结果 流式细胞仪显示,体外分离培养的第3代MSC,CD44阳性细胞表达率为97.8%±0.9%;CD90阳性细胞表达率为96.8%±1.4%;CD29阳性细胞表达率为97.6%±2.4%;而CD11b/c阳性细胞表达率为13.2%±0.6%; CD34阳性细胞表达率为1.2%±0.5%。诱导7 d后,与对照组长梭形细胞相比,ATRA组部分细胞为圆形、短梭形单层排列;联合诱导组的大部分细胞为圆形、短梭形,细胞密集处呈鹅卵石样排列。碱性磷酸酶染色显示,对照组细胞为阴性;ATRA组部分细胞阳性;联合诱导组阳性细胞数明显增多。免疫细胞化学显示,ATRA组和联合诱导组细胞cytokeratin-18阳性表达率分别为29.47%±1.08%和47.52%±2.13%,显著高于对照组（P ＜ 0.05）;E-cadherin阳性表达率分别为14.88%±2.46%和36.15%±1.13%,也显著高于对照组（P ＜ 0.05）。 结论 在体外模拟的急性肾衰竭微环境中加入ATRA可诱导MSC部分分化为肾小管上皮样细胞。联合EGF、BMP-7共同诱导能进一步促进MSC向肾小管上皮样细胞分化。     

不同浓度麝香含药血清对骨髓间充质干细胞迁移影响的实验研究

目的探讨麝香对外源性骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMSCs)增殖和迁移的影响。方法将60只SD大鼠随机分为麝香高、中、低剂量组及空白对照组,制备麝香含药血清及生理盐水血清。15只SD大鼠利用全骨髓贴壁法分离BMSCs,培养至P3代,通过形态学观察、表型鉴定、成骨成脂诱导鉴定BMSCs,鉴定认为培养成功后通过麝香含药血清干预BMSCs,检测细胞增殖率,利用Transwell实验检测麝香含药血清对BMSCs迁移的影响。结果外源性大鼠BMSCs呈梭形贴壁生长,生长状态良好;表型鉴定:CD45、CD34阴性表达,CD44、CD90阳性表达;细胞成骨、成脂诱导后可定向成骨、成脂分化;不同浓度麝香组与对照组比较均能提高BMSCs增殖率(P0.05);与对照组比较,不同浓度麝香在24 h、48 h、72 h均增加BMSCs迁移(P0.05),以低浓度组效果最佳。结论麝香含药血清可以促进BMSCs增殖,促进BMSCs的体外迁移。     

不同来源血清体外培养骨髓间充质干细胞的研究

目的 适当的血清浓度可维持骨髓问充质干细胞(bone marrow mesenchymal stem cells,BMSCs)的体外培养,而不同来源的血清对BMSCs的培养效果是否小同.本研究探讨自体血清、脐带血清、AB血清、胎牛血清在体外培养人BMSCs的可行性.方法 Ficoll密度梯度离心法结合贴壁法分离纯化人BMSCs,在培养过程中分别加入白体血清、脐带血清、AB血清、胎牛血清,观察比较细胞形态、表面抗原、生长曲线及各组在诱导剂作用下表面抗原和诱导分化的相关性.结果 从BMSCs的形态学、生长曲线、表面抗原、诱导分化上看各组无明显差异,生长状况良好.结论 自体血清、脐带血清、AB血清、胎牛血清均可维持BMSCs的体外培养,而自体血清解决异种和异体血清带来的一些潜在的风险,更为安全.     

体外培养的人脂肪间充质干细胞生物学特性的研究

目的:了解体外培养的人脂肪间充质干细胞的生物学特性及其体外成脂和成骨的能力.方法:体外培养人脂肪间充质干细胞并传代计数,行成骨和成脂诱导,流式细胞仪检测其细胞增殖周期与表面分子.结果:人脂肪干细胞经过体外培养均一的阳性表达CD44、CD106,而CD49d、CD34、CD45和HLA-DR表达阴性.细胞周期分析表明:G0/G1、S和G 2/M所占比例分别为79.1%、19.7%和1.3%.分离细胞在诱导体系下可以向成骨和成脂方向分化.结论:脂肪间充质干细胞具有特殊的生物学特点,体外能够向成骨和成脂方向分化.     

CD105、CD133在人肝癌细胞株HepG-2的表达情况及生物学性状的体外研究

目的 观察人肝癌细胞株HepG-2中CD105、CD133的表达情况并对不同亚群的生物学性状进行体外研究.方法 采用含10％胎牛血清的DMEM培养HepG-2.流式细胞分选仪检测CD105、CD133表达情况并分选出CD105+ CD133+、CD105-CD133+、CD105+ CD133-、CD105-CD133-亚群.CCK-8和Transwell侵袭实验分别检测各细胞亚群增殖及侵袭能力;软琼脂培养试验检测细胞成球能力.结果 四种不同细胞亚群的比例分别为99.57％,0.2％,0.2％和0.03％.CD133阳性亚群增值能力和成球能力较CD133-及未分选细胞强;而CD105+亚群侵袭能力较CD105-及未分选细胞强.结论 CD105在人肝癌细胞株HepG-2的表达与其侵袭能力有关,CD133与其增殖成球能力有关.CD105+ CD133+亚群在人肝癌细胞株HepG-2中具有干细胞特性.     

不同来源成体骨髓间充质干细胞调控免疫功能的比较研究

目的 比较霍奇金淋巴瘤(HL)、非霍奇金淋巴瘤(NHL)患者与正常人骨髓间充质干细胞(MSC)的免疫调节能力.方法 获取正常人、HL和NHL患者的骨髓MSC,用低血清培养液进行培养.采用流式细胞仪检测骨髓MSC的免疫表型;应用酶联免疫吸附试验检测骨髓MSC培养上清液中转化生长因子β1(TGF-β1)的水平;采用Transwell培养体系检测骨髓MSC抑制T淋巴细胞增殖的能力;应用混合淋巴细胞反应检测骨髓MSC抑制异体T淋巴细胞增殖的能力.结果 正常人、HL和NHL患者骨髓间充质干细胞具有相似的细胞形态和免疫表型,均具有分泌TGF-β1的能力,均不表达HLA-DR和共刺激分子CD80、CD86和CD40.HL和NHL患者骨髓MSC具有抑制异体T淋巴细胞增殖的能力,这种抑制能力随着MSC细胞数量的增加而增强,并可以被抗TGF-β1抗体所逆转.体外诱导分化后的骨髓MSC仍然具有抑制异体T淋巴细胞增殖的能力.结论 HL和NHL患者骨髓MSC具有和正常成人骨髓MSC相同的免疫调控能力,这种抑制T淋巴细胞增殖的能力不随着其体外诱导分化而改变.     

The platelet-rich plasma and mesenchymal stem cell milieu: A review of therapeutic effects on bone healing

Platelet-rich plasma is autologous plasma that contains concentrated platelets compared to whole blood. It is relatively inexpensive to produce, can be easily isolated from whole blood, and can be administered while the patient is in the operating room. Further, because platelet-rich plasma is an autologous therapy, there is minimal risk for adverse reactions to the patient. Platelet-rich plasma has been used to promote bone regeneration due to its abundance of concentrated growth factors that are essential to wound healing. In this review, we summarize the methods for producing platelet-rich plasma and the history of its use in bone regeneration. We also summarize the growth factor profiles derived from platelet-rich plasma, with emphasis on those factors that play a direct role in promoting bone repair within the local fracture environment. In addition, we discuss the potential advantages of combining platelet-rich plasma with mesenchymal stem cells, a multipotent cell type often obtained from bone marrow or fat, to improve craniofacial and long bone regeneration. We detail what is currently known about how platelet-rich plasma influences mesenchymal stem cells in vitro, and then highlight the clinical outcomes of administering platelet-rich plasma and mesenchymal stem cells as a combination therapy to promote bone regeneration in vivo.     

Editorial Commentary: Injection of Platelet-Rich Plasma Appears Superior to Hyaluronic Acid and Adipose- or Bone-Derived Marrow Stem Cells for Knee Osteoarthritis

Injection therapy for knee osteoarthritis continues to be a controversial topic. Commonly accepted treatment options are corticosteroid and hyaluronic acid injections, but recently platelet-rich plasma also has been a promising biologic treatment option. Adipose and bone marrow–derived mesenchymal stem cells have been applied clinically, but there is no strong supporting evidence for their use. It is also currently unknown whether stem cells can regenerate cartilage. As there is no cure for painful knee osteoarthritis, injection therapy can provide symptom relief. Recent network meta-analyses suggest that platelet-rich plasma provides the best functional improvement and safety for knee osteoarthritis, and adipose-derived mesenchymal stem cells provide excellent pain relief. We must bear in mind that other network meta-analyses report different results, and a challenge of network meta-analysis is inconsistency that can lead to biased treatment effect estimates.     

The effectiveness of intradiscal biologic treatments for discogenic low back pain: a systematic review

BACKGROUND CONTEXTThere are limited treatments for discogenic low back pain. Intradiscal injections of biologic agents such as platelet-rich plasma (PRP) or stem cells (SC) are theorized to have regenerative properties and have gained increasing interest as a possible treatment, but the evidence supporting their use in clinical practice is not yet well-defined.PURPOSEDetermine the effectiveness of intradiscal biologics for treating discogenic low back pain.STUDY DESIGNPRISMA-compliant systematic review.PATIENT SAMPLEPatients with discogenic low back pain confirmed by provocation discography or clinical and imaging findings consistent with discogenic pain.OUTCOME MEASURESThe primary outcome was the proportion of individuals with ≥50% pain relief after intradiscal biologic injection at 6 months. Secondary outcomes included ≥2-point pain score reduction on NRS; patient satisfaction; functional improvement; decreased use of other health care, including analgesics and surgery; and structural disc changes on MRI.METHODSComprehensive literature search performed in 2018 and updated in 2020. Interventions included were biologic therapies including mesenchymal stem cells, platelet rich plasma, microfragmented fat, amniotic membrane-based injectates, and autologous conditioned serum. Any other treatment (sham or active) was considered for comparative studies. Studies were independently reviewed.RESULTSThe literature search yielded 3,063 results, 37 studies were identified for full-text review, and 12 met established inclusion criteria for review. The quality of evidence on effectiveness of intradiscal biologics was very low. A single randomized controlled trial evaluating platelet-rich plasma reported positive outcomes but had significant methodological flaws. A single trial that evaluated mesenchymal stem cells was negative. Success rates for platelet-rich plasma injectate in aggregate were 54.8% (95% Confidence Interval: 40%–70%). For mesenchymal stem cells, the aggregate success rate at six months was 53.5% (95% Confidence Interval: 38.6%–68.4%), though using worst-case analysis this decreased to 40.7% (95% Confidence Interval: 28.1%–53.2%). Similarly, ≥30% functional improvement was achieved in 74.3% (95% Confidence Interval: 59.8%–88.7%) at six months but using worst-case analysis, this decreased to 44.1% (95% Confidence Interval: 28.1%–53.2%).CONCLUSIONLimited observational data support the use of intradiscal biologic agents for the treatment of discogenic low back pain. According to the Grades of Recommendation, Assessment, Development and Evaluation System, the evidence supporting use of intradiscal mesenchymal stem cells and platelet-rich plasma is very low quality.     

A comparative histologic analysis of tissue-engineered bone using platelet-rich plasma and platelet-enriched fibrin glue.

OBJECTIVE: The aim of this study was to compare the effects of platelet-rich plasma (PRP) and platelet-enriched fibrin glue on bone formation in bone tissue engineering. STUDY DESIGN: PRP was mixed with bone marrow mesenchymal stem cells and bone morphogenetic protein-2 (BMP-2), and the composites were injected into the subcutaneous space on the dorsum of nude mice. On the contralateral side of the dorsum, platelet-enriched fibrin glue/bone marrow mesenchymal stem cells/BMP-2 composites were injected. Bone formation was evaluated after 12 weeks. RESULTS: The volumes of subcutaneous nodules formed in nude mice were 55 +/- 18 microL at the PRP/bone marrow mesenchymal stem cells/BMP-2 sites and 135 +/- 27 microL at the platelet-enriched fibrin glue/bone marrow mesenchymal stem cells/BMP-2 sites. Histomorphometric analysis demonstrated that the nodules contained 14.9 +/- 4.1% newly formed bone when using PRP and 19.8 +/- 3.6% newly formed bone when using platelet-enriched fibrin glue. CONCLUSION: The results indicated that the osteogenic characteristics of platelet-enriched fibrin glue are superior to PRP in bone tissue engineering.     

Editorial Commentary: Paving a Road Requires a Well-Mixed Cement Stem Cells,Platelet-Rich Plasma,and Shoulder Rotator Cuff Healing

The process of healing in musculoskeletal tissues is complex, and the addition of devices, including platelet-rich plasma and mesenchymal stem cells, to biologically enhance it may favor its optimization. This work shows in a compelling fashion that it is possible to produce the right admixture of physical and biological factors to make it happen in rotator cuff repair.     

Stromal stem cells and platelet-rich plasma improve bone allograft integration

Early vascular invasion is a key factor in bone allograft incorporation. It may reduce the complications related to slow and incomplete bone integration. Bone-marrow-derived stromal stem cells associated with platelet-rich plasma are potent angiogenic inducers proven to release vascular endothelial growth factor. Our goal was to test whether the combination of stromal stem cells and platelet-rich plasma is able to increase massive allograft integration in a large animal model with sacrifice at 4 months. A critical defect was made in the mid-diaphysis of the metatarsal bone of 10 sheep; the study group received an allograft plus stromal stem cells, platelet-rich plasma, and collagen (six animals) and the control group received only the allograft (four animals). Investigation was done with radiographs, mechanical tests and histomorphometric analysis, including new vascularization. Results showed substantial new bone formation in the allograft of the study group. Bone formation is correlated with better vascular invasion and remodeling of the graft in the study group. These results confirm the key role played by stromal stem cells and platelet-rich plasma in bone repair. Further studies are needed to better define the role stromal stem cells play when implanted alone.     

Autologous preparations rich in growth factors promote proliferation and induce VEGF and HGF production by human tendon cells in culture.

Blood platelets become activated and aggregate at the site of vessel injury. Upon activation by thrombin, platelets release storage pools of proteins and growth factors (GFs), including those involved in tissue repair. Our goal was to evaluate the potential beneficial effect of proteins released from platelet-rich clots on tendon healing. PDGF, TGF-beta-1, IGF-I, HGF, VEGF and EGF were measured in human platelet-poor plasma (PPP) and in the releasates collected from either platelet-poor or platelet-rich clots prepared in vitro. We then studied the effects of the releasates on human tendon cells in culture. Releasates from both platelet-rich and platelet-poor clots stimulated tendon cell proliferation, in contrast to un-clotted PPP. The mitogenic activity of the supernatants was not decreased by the thrombin inhibitor, hirudin. Cultured tendon cells synthesise VEGF and HGF in the presence of PPP-clots and PRP-clot releasates, thus the synthesised amount was significantly higher with supernatants from platelet-rich clots than supernatants from a platelet-poor clot (p < 0.05). These results suggest that administering autologous platelet-rich clots may be beneficial to the treatment of tendon injuries by inducing cell proliferation and promoting the synthesis of angiogenic factors during the healing process.     

Editorial Commentary: Injections for Knee Osteoarthritis: Doc,You Gotta Help Me!

Injections for the pain caused by knee osteoarthritis have been the focus of significant research for the last few decades. Systematic reviews and meta-analyses suggest that platelet-rich plasma (PRP) can provide up to 12 months of pain relief in these patients, superior to both cortisone and hyaluronic acid. There is also some evidence for a synergistic effect when combining both PRP and hyaluronic acid. Bone marrow aspirate concentrate (BMAC) has significantly greater levels of interleukin-1ra than PRP, as well as a small concentration of mesenchymal stromal cells. However, BMAC is yet unproven in its efficacy, and obtaining BMAC is not as simple as taking blood. Research into the use of expanded autologous and allogenic mesenchymal stem cells continues and shows future promise. For today, PRP remains the gold standard for the treatment of pain associated with knee osteoarthritis.     

Articular Cartilage Restoration Requires Cells,Scaffolds, Growth Factors,and Mechanical Stimulation

Tissue engineering requires cells, scaffolds, growth factors, and mechanical stimulation. In terms of cartilage restoration or repair, various innovative approaches are evolving, using host or allograft cells, biomimetic scaffolds, matrices, or membranes including hyaluronic acid, as well as diverse biological and growth factors. A current approach for the treatment of chondral or osteochondral defects enhances a microfracture procedure (introducing autologous, mesenchymal stem cells) with dehydrated micronized allograft extracellular matrix (scaffold), platelet-rich plasma (containing anabolic, anticatabolic, and anti-inflammatory growth factors), a fibrin glue sealant, and careful rehabilitation providing mechanical stimulation. Early results are encouraging; long-term outcomes including a larger number of study subjects remain to be reported.