MR示踪技术在干细胞移植治疗软骨缺损中的研究进展

关节软骨缺损临床十分常见, 但目前的治疗方法均存在修复不完全的缺陷。间充质干细胞移植治疗的发展为再生修复关节软骨缺损提供了新的治疗策略, 但是作为组织修复执行者的干细胞移植后的在体迁徙分布、增殖及转归过程, 目前尚无安全无创、实时动态的监测手段, 因此难以明确外源性干细胞在关节软骨缺损再生修复中所扮演的角色。而MR在体示踪细胞技术为解决上述问题提供了新思路。MRI具有无创、无电离辐射、时间空间分辨率高、对比度好等优点, 协同MRI对比剂, 既可无创提供关节软骨的详细解剖结构信息, 还可动态评估移植干细胞的归宿。笔者就MR示踪技术在干细胞移植治疗软骨缺损中的最新研究进展进行综述, 探讨其优势、局限性及未来前景。     

不同细胞移植修复兔全层关节软骨缺损的比较研究

目的 :比较软骨细胞、骨髓基质细胞及成纤维细胞对全层关节软骨缺损的修复作用。材料和方法 :取幼兔的软骨细胞、骨髓基质细胞及成纤维细胞 ,共 3种有生成软骨潜力的细胞进行体外分离培养 ;以聚乳酸 (PLA)为载体 ,将培养的原代细胞植入PLA支架上 ,形成细胞 -PLA复合物。于 2 8只成年新西兰大白兔的股骨滑车关节面上造成直径 4 5mm、深 3 0mm的全层关节软骨缺损 ,将 3种细胞 -PLA复合物分别植入关节软骨缺损处。植入细胞 -PLA复合物为实验组 ,单纯植入PLA支架为对照组。术后 6周、12周观察缺损修复情况及新生组织类型。结果 :软骨细胞移植组为软骨样组织修复 ,分界明显 ,甲苯胺兰及Ⅱ型胶原染色阳性 ;软骨下骨部分重建 ;细胞排列紊乱。骨髓基质细胞移植组为软骨样组织修复 ,分界不明显 ,甲苯胺兰及Ⅱ型胶原染色阳性 ;软骨下骨重建良好 ,软骨下潮线恢复 ;细胞排列趋于正常。成纤维细胞移植组为纤维组织修复 ,甲苯胺兰及Ⅱ型胶原染色阴性 ;软骨下潮线消失。对照组为纤维组织修复。结论 :软骨细胞、骨髓基质细胞移植修复软骨缺损明显优于成纤维细胞及对照组。骨髓基质细胞与软骨细胞移植组的修复结果无统计学差异 ,但骨髓基质细胞修复组织的细胞排列有序 ,软骨下骨重建良好 ,与周围组织融合密切 ,更接近正?     

Mesenchymal stem cells for the treatment of cartilage lesions: from preclinical findings to clinical application in orthopaedics

Purpose

The aim of this systematic review is to examine the available clinical evidence in the literature to support mesenchymal stem cell (MSC) treatment strategies in orthopaedics for cartilage defect regeneration.

Methods

The research was performed on the PubMed database considering the English literature from 2002 and using the following key words: cartilage, cartilage repair, mesenchymal stem cells, MSCs, bone marrow concentrate (BMC), bone marrow-derived mesenchymal stem cells, bone marrow stromal cells, adipose-derived mesenchymal stem cells, and synovial-derived mesenchymal stem cells.

Results

The systematic research showed an increasing number of published studies on this topic over time and identified 72 preclinical papers and 18 clinical trials. Among the 18 clinical trials identified focusing on cartilage regeneration, none were randomized, five were comparative, six were case series, and seven were case reports; two concerned the use of adipose-derived MSCs, five the use of BMC, and 11 the use of bone marrow-derived MSCs, with preliminary interesting findings ranging from focal chondral defects to articular osteoarthritis degeneration.

Conclusions

Despite the growing interest in this biological approach for cartilage regeneration, knowledge on this topic is still preliminary, as shown by the prevalence of preclinical studies and the presence of low-quality clinical studies. Many aspects have to be optimized, and randomized controlled trials are needed to support the potential of this biological treatment for cartilage repair and to evaluate advantages and disadvantages with respect to the available treatments.

Level of evidence

IV.     

脊髓损伤干细胞治疗的研究现状与未来

脊髓损伤是一种严重的中枢神经系统损伤,致残率高、并发症多、预后差。近二十年,尽管脊髓损伤的外科治疗取得一定进展,但仍无法从根本上改善脊髓损伤患者的临床预后。干细胞治疗被视为再生医学中最具应用前景的治疗手段之一。近年来,干细胞移植、刺激自体潜在的干细胞分化等干细胞治疗脊髓损伤已取得一定成果,但其临床转化仍存在诸多瓶颈。笔者回顾近年来脊髓损伤干细胞治疗的研究现状并对其未来进行展望,为脊髓损伤干细胞治疗相关研究提供参考。     

MR imaging of cartilage repair surgery of the knee

Articular cartilage is a complex tissue with unique properties that are essential for normal joint function. Many processes can result in cartilage injury, ranging from acute trauma to degenerative processes. Articular cartilage lacks vascularity, and therefore most chondral defects do not heal spontaneously and may require surgical repair. A variety of cartilage repair techniques have been developed and include bone marrow stimulation (microfracture), osteochondral autograft transfer system (OATS) or osteochondral allograft transplantation, autologous chondrocyte implantation (ACI), matrix-assisted chondrocyte implantation (MACI), and other newer processed allograft cartilage techniques. Although arthroscopy has long been considered as the gold standard for evaluation of cartilage after cartilage repair, magnetic resonance (MR) imaging is a non-invasive method to assess the repair site and can be scored using Magnetic resonance Observation of Cartilage Repair Tissue (MOCART). MR also provides additional evaluation of the subchondral bone and for other potential causes of knee pain or internal derangement. Conventional MR can be used to evaluate the status of cartilage repair and potential complications. Compositional MR sequences can provide supplementary information about the biochemical contents of the reparative tissue. This article reviews the various types of cartilage repair surgeries and their postoperative MR imaging appearances.     

MR imaging of cartilage repair surgery of the knee

Articular cartilage is a complex tissue with unique properties that are essential for normal joint function. Many processes can result in cartilage injury, ranging from acute trauma to degenerative processes. Articular cartilage lacks vascularity, and therefore most chondral defects do not heal spontaneously and may require surgical repair. A variety of cartilage repair techniques have been developed and include bone marrow stimulation (microfracture), osteochondral autograft transfer system (OATS) or osteochondral allograft transplantation, autologous chondrocyte implantation (ACI), matrix-assisted chondrocyte implantation (MACI), and other newer processed allograft cartilage techniques. Although arthroscopy has long been considered as the gold standard for evaluation of cartilage after cartilage repair, magnetic resonance (MR) imaging is a non-invasive method to assess the repair site and can be scored using Magnetic resonance Observation of Cartilage Repair Tissue (MOCART). MR also provides additional evaluation of the subchondral bone and for other potential causes of knee pain or internal derangement. Conventional MR can be used to evaluate the status of cartilage repair and potential complications. Compositional MR sequences can provide supplementary information about the biochemical contents of the reparative tissue. This article reviews the various types of cartilage repair surgeries and their postoperative MR imaging appearances.     

Cell-based therapies and imaging in cardiology

Cell therapy for cardiac repair has emerged as one of the most exciting and promising developments in cardiovascular medicine. Evidence from experimental and clinical studies is increasing that this innovative treatment will influence clinical practice in the future. But open questions and controversies with regard to the basic mechanisms of this therapy continue to exist and emphasise the need for specific techniques to visualise the mechanisms and success of therapy in vivo. Several non-invasive imaging approaches which aim at tracking of transplanted cells in the heart have been introduced. Among these are direct labelling of cells with radionuclides or paramagnetic agents, and the use of reporter genes for imaging of cell transplantation and differentiation. Initial studies have suggested that these molecular imaging techniques have great potential. Integration of cell imaging into studies of cardiac cell therapy holds promise to facilitate further growth of the field towards a broadly clinically useful application.     

Articular cartilage repair in the adolescent athlete: is autologous chondrocyte implantation the answer?

OBJECTIVE: To determine the evidence base for recommendations regarding autologous chondryocyte implantation in adolescent athletes. MATERIALS AND METHODS: All literature on articular cartilage repair from MEDLINE search dated 1990 to 2006 was reviewed. The majority of articles describe surgical technique and indications. Three techniques for secondary articular cartilage repair have been identified: autologous chondrocyte implantation, autologous osteochondral implants, and marrow stimulation techniques. The initial literature search identified 4 studies that reported the effectiveness and durability of autologous chondrocyte implantation in adults and 2 studies that reported the outcomes of autologous chondrocyte implantation in adolescent athletes. No results of osteochondral implantation or marrow stimulation techniques in adolescent athletes have been published. RESULTS: Acceptable repair rates with all 3 techniques have been reported in adult athletes. Two studies reported high success using autolgous chondrocyte implantation (ACI) in children. CONCLUSIONS: Articular cartilage injury in young athletes remains a difficult problem. The ideal situation is early diagnosis and primary repair, particularly with lesions of the knee, elbow, and ankle. In cases where primary repair is not possible or has been unsuccessful and the lesion is large or symptomatic, secondary repair with either marrow stimulation, microfracture, autologous chondrocyte implantation, or autologous osteochondral grafting may be used. However, at present only the results of ACI repair have been reported for adolescent athletes.     

自体MSCs/Chondro-Gide工程化软骨再生修复技术的大动物实验

目的探索自体MSCs/Chondro-Gide工程化软骨修复技术用于软骨再生治疗的可行性。方法 12只山羊随机分为实验组、自体基质诱导软骨再生（autologous matrix-induced chondrogenesis,AMIC）治疗组及空白对照组,实验组采用自体MSCs/Chondro-Gide工程化软骨修复技术修复软骨缺损;AMIC治疗组采用AMIC技术,空白对照组不植入任何材料。术后8周行大体观察、关节镜检查、影像学检测、组织学检测、改良Wakitani法评分,评价其对关节软骨缺损的再生修复效果。结果 8周大体观察实验组软骨缺损的修复及整合良好;MRI及关节镜提示软骨缺损修复表面光滑,弹性可;组织学检测修复区域有较多幼稚软骨细胞;AMIC组可见修复区为纤维组织修复;空白组为少量纤维组织覆盖缺损底面。8周及16周改良Wakitani评分示：实验组修复效果优于AMIC组及空白对照组。结论自体MSCs/Chondro-Gide工程化软骨修复技术创伤小,操作简便,能显著促进关节软骨缺损的再生修复,具有较高的科学价值及临床应用前景。     

Cartilage repair: generations of autologous chondrocyte transplantation

Articular cartilage in adults has a limited capacity for self-repair after a substantial injury. Surgical therapeutic efforts to treat cartilage defects have focused on delivering new cells capable of chondrogenesis into the lesions. Autologous chondrocyte transplantation (ACT) is an advanced cell-based orthobiologic technology used for the treatment of chondral defects of the knee that has been in clinical use since 1987 and has been performed on 12,000 patients internationally. With ACT, good to excellent clinical results are seen in isolated post-traumatic lesions of the knee joint in the younger patient, with the formation of hyaline or hyaline-like repair tissue. In the classic ACT technique, chondrocytes are isolated from small slices of cartilage harvested arthroscopically from a minor weight-bearing area of the injured knee. The extracellular matrix is removed by enzymatic digestion, and the cells are then expanded in monolayer culture. Once a sufficient number of cells has been obtained, the chondrocytes are implanted into the cartilage defect, using a periosteal patch over the defect as a method of cell containment. The major complications are periosteal hypertrophy, delamination of the transplant, arthrofibrosis and transplant failure. Further improvements in tissue engineering have contributed to the next generation of ACT techniques, where cells are combined with resorbable biomaterials, as in matrix-associated autologous chondrocyte transplantation (MACT). These biomaterials secure the cells in the defect area and enhance their proliferation and differentiation.     

间充质干细胞外泌体在创伤修复再生中作用的研究进展

间充质干细胞（MSCs）外泌体能够通过旁分泌作用,发挥类似干细胞的促进组织器官修复再生的功能,避免了直接移植MSCs的风险,如致瘤、伦理、免疫排斥反应等。MSCs外泌体参与细胞通讯,维持微环境的稳态,促进细胞的增殖、迁移及细胞外基质的修复再生,且能够在不同物种之间传递,却不会引起明显的免疫反应,在组织器官的修复与再生方...     

Biological enhancement of meniscus repair and replacement

When a meniscus injury occurs, it is generally accepted that preserving the meniscus is important for life-long joint preservation. Traditional suture repair of the meniscus has good results; however, the healing potential of meniscus tissue remains as a biological challenge because it is not a completely vascularized structure. For this reason, investigators have continued to search for adjuncts to improve clinical results. Mechanical adjuncts, local factor enhancement, scaffolds, gene therapy, and cell therapy have all been examined as options for improvement of biology and structure. This study reviews the basic science and clinical application of these modalities and provides an assessment of techniques on the horizon.     

组织工程软骨移植物修复兔关节软骨缺损

目的　观察组织工程软骨移植物修复兔关节软骨缺损的效果。　方法　经软骨起源诱导后的兔骨髓间质干细胞(mesenchymalstemcells,MSCs),与牛Ⅰ型胶原及人纤维蛋白相混合制成组织工程软骨移植物。60只5个月龄的日本大耳白兔均分为软骨移植物组、单纯载体对照组和空白对照组,观察各组修复兔股骨髁关节软骨全层缺损的效果。　结果　软骨移植物组12周时已形成正常厚度的软骨层及完整的软骨下骨板,O'drilscoll组织学评分18.22±2.45,Ⅱ型胶原含量97.9%,甲苯胺蓝变色反应表明其与周围正常软骨无明显区别,为透明软骨组织修复。而对照组12周时为纤维软骨修复,后期为纤维组织和板层骨修复。　结论　该组织工程软骨移植物作为软骨移植的替代物是可行的。     

Autologe Chondrozytentransplantation zur Behandlung von Knorpeldefekten des Kniegelenks

BACKGROUND: Currently the use of autologous chondrocytes as a cartilage-repair procedure for the repair of injured articular cartilage of the knee joint, is recommended. METHODS: This review presents the technique of autologous chondrocyte transplantation (ACT) and their modifications as matrix-associated autologous chondrocyte transplantation (MACT). Beside the surgical procedure the experimental and clinical results are discussed. Furthermore the major complications and the indication guidelines are presented. RESULTS: Articular cartilage in adults has a poor ability to self-repair after a substantial injury. Surgical therapeutic efforts in treating cartilage defects have focused on bringing new cells capable of chondrogenesis into the lesions. With ACT good to excellent clinical results are seen in isolated posttraumatic lesions of the knee joint in the younger patient with the formation of hyaline-like repair tissue. The major complications are periosteal hypertrophy, delamination of the transplant, arthrofibrosis and transplant failure. The current limitations include osteoarthritic defects and higher patient age. CONCLUSION: With the right indication and operative technique ACT is an effective and save option for the treatment of large full thickness cartilage defect of the knee joint.     

间充质干细胞在组织修复与再生中的应用

由于间充质干细胞具有自我更新、多向分化潜能,且容易获取及体外扩增培养,成为近年来成体干细胞研究的热点。间充质干细胞既可以作为修复组织的细胞来源,还可能同时参与多种组织的更新。目前在多个领域显示出重要的应用前景,包括组织工程的种子细胞、基因转染的细胞载体等。     

人脐血间充质干细胞移植促进大鼠颅脑创伤后神经功能的恢复

目的 将人脐带血(human umbilical cord blood,HUCB)间充质干细胞(mesenchymal stem cells,MSCs)注射到创伤性脑损伤(TBI)大鼠顶叶皮层及海马区,观察神经细胞标志物的表达和促进神经功能的恢复.方法 HUCB-MSCs用双苯酰亚胺(bis-benzimide)标记24 h,通过立体定向将细胞注射到损伤脑组织内.全部大鼠分为假损伤组、损伤组(TBI)、对照组(TBI+PBS)和治疗组(TBI+MSCs).用免疫组化和免疫荧光标记的方法检测移植细胞的存活、迁移和分化情况,用神经损伤严重程度评分(NSS)对神经功能恢复结果进行评价.结果 在接受移植的脑创伤大鼠局部有大量的MSCs存活,一些细胞分化为神经元或神经胶质细胞,并表达NSE和GFAP等神经细胞的标志物,治疗组的神经功能评分较其他组有明显的改善.结论 HUCB-MSCs可明显改善脑创伤后神经功能的恢复,并能很好替代骨髓MSCs而用于干细胞移植.     

细胞移植用于心肌修复--细胞心肌成形术的研究进展

由于心肌细胞的增殖能力很低，细胞移植作为一种新的治疗方法用于改善心功能及心肌活力已受到广泛的关注。目前已有胚胎干细胞、骨髓间充质干细胞和内皮干细胞在体外诱导分化为心肌细胞；动物实验中用于心肌移植的细胞有胚胎心肌细胞、造血干细胞、骨髓间充质干细胞、骨骼肌成肌细胞、内皮干细胞、肝干细胞和神经干细胞。其中成肌细胞移植用来改善心肌梗死后的心脏功能，已有临床报道，并取得成功。     

胚胎干细胞在脊髓损伤中的应用

神经干细胞具有自我增殖、分化、迁移及建立突触联系的特征,并可促进损伤神经组织的修复与再生。最近发现,经胚胎干细胞诱导的神经前体细胞植入受损伤的脊髓中,可分化为神经元和神经胶质细胞,并能促进脊髓功能的恢复,提示胚胎干细胞在中枢神经系统的治疗中具有广阔的应用前景。     

人脐血间充质干细胞移植促进大鼠颅脑创伤后神经功能的恢复

目的 将人脐带血(human umbilical cord blood,HUCB)间充质干细胞(mesenchymal stem cells,MSCs)注射到创伤性脑损伤(TBI)大鼠顶叶皮层及海马区,观察神经细胞标志物的表达和促进神经功能的恢复.方法 HUCB-MSCs用双苯酰亚胺(bis-benzimide)标记24 h,通过立体定向将细胞注射到损伤脑组织内.全部大鼠分为假损伤组、损伤组(TBI)、对照组(TBI+PBS)和治疗组(TBI+MSCs).用免疫组化和免疫荧光标记的方法检测移植细胞的存活、迁移和分化情况,用神经损伤严重程度评分(NSS)对神经功能恢复结果进行评价.结果 在接受移植的脑创伤大鼠局部有大量的MSCs存活,一些细胞分化为神经元或神经胶质细胞,并表达NSE和GFAP等神经细胞的标志物,治疗组的神经功能评分较其他组有明显的改善.结论 HUCB-MSCs可明显改善脑创伤后神经功能的恢复,并能很好替代骨髓MSCs而用于干细胞移植.     

人脐血间充质干细胞移植促进大鼠颅脑创伤后神经功能的恢复

目的 将人脐带血(human umbilical cord blood,HUCB)间充质干细胞(mesenchymal stem cells,MSCs)注射到创伤性脑损伤(TBI)大鼠顶叶皮层及海马区,观察神经细胞标志物的表达和促进神经功能的恢复.方法 HUCB-MSCs用双苯酰亚胺(bis-benzimide)标记24 h,通过立体定向将细胞注射到损伤脑组织内.全部大鼠分为假损伤组、损伤组(TBI)、对照组(TBI+PBS)和治疗组(TBI+MSCs).用免疫组化和免疫荧光标记的方法检测移植细胞的存活、迁移和分化情况,用神经损伤严重程度评分(NSS)对神经功能恢复结果进行评价.结果 在接受移植的脑创伤大鼠局部有大量的MSCs存活,一些细胞分化为神经元或神经胶质细胞,并表达NSE和GFAP等神经细胞的标志物,治疗组的神经功能评分较其他组有明显的改善.结论 HUCB-MSCs可明显改善脑创伤后神经功能的恢复,并能很好替代骨髓MSCs而用于干细胞移植.