BMSCs-壳聚糖凝胶复合体移植治疗椎间盘退变的实验研究

目的 探讨兔BMSCs-壳聚糖凝胶复合体移植治疗椎间盘髓核缺损退变的效果,为临床应用提供实验依据. 方法 6只健康1月龄新西兰白兔,雌雄不限,体重1.0～1.5 kg.取骨髓2 mL,分离培养BMSCs.取第3代BMSCs,5-BrdU活细胞示踪剂标记,与壳聚糖凝胶混匀,制备BMSCs-壳聚糖凝胶复合体.将6只动物建立兔椎间盘髓核缺损退变模型,并随机分为3组(n=2):正常对照组仅分离暴露椎间盘,不作任何处理;移植治疗组将30 μL自体BMSCs-壳聚糖凝胶复合体注射入缺损椎间盘中心;缺损退变组仅注射入0.01 mol/L PBS液30 μL.移植后4周处死动物,取出移植修复的椎间盘,行细胞5-BrdU标记检测、HE、aggrecan番红.染色及Col Ⅱ免疫组织化学染色;Col Ⅱ免疫组织化学染色切片行灰度值测定. 结果 细胞标记检测发现,自体BMSCs移植后继续存活并增殖,形成细胞克隆.正常对照组及移植组椎间盘HE染色示椎间盘结构清晰,髓核组织及外周纤维环分界清晰,细胞核及细胞浆染色明显;缺损退变组示椎间盘结构紊乱,髓核组织和外周纤维化分界不清.aggrecan番红O染色示正常对照组及移植治疗组椎间盘染色明显,椎间盘结构清晰;缺损退变组椎间盘结构紊乱,髓核组织和外周纤维化分界不清.Col Ⅱ免疫组织化学染色示正常对照组以中央髓核组织染色为主,呈黄褐色阳性反应,椎间盘结构清晰;移植治疗组中央髓核组织呈阳性反应,细胞间质可见明显黄褐色,大体结构仍保持完整;缺损退变组染色较前两组浅,且结构不清.3组Col Ⅱ免疫组织化学染色切片行灰度值测定,正常对照组为223.84±3.93,与移植治疗组(221.03±3.53)比较差异无统计学意义(P>0.05),但两组与缺损退变组(172.50±3.13)比较,差异均有统计学意义(P<0.05). 结论 兔BMSCs-壳聚糖凝胶复合体可修复椎间盘缺损退变,为临床应用可注射式组织工程髓核移植治疗椎间盘退变奠定实验基础.     

TGF-β1干预下体内兔骨髓间充质干细胞对退变椎间盘治疗的实验研究

[目的]评价在TGF-β1干预下的兔间充质干细胞移植到兔退变椎间盘后是否可诱导向髓核细胞分化并增加蛋白多糖和Ⅱ型胶原的含量。[方法]采用体外细胞培养技术，将兔骨髓间充质干细胞白骨髓血中分离、纯化和培养，成功传代、纯化后并在TGF-β1干预下植入兔退变椎间盘的模型中。分别于2、4、6、8周用间苯三酚分光光度法测定蛋白多糖含量的变化；免疫组化法测定Ⅱ型胶原的含量变化。所得数据经SPSS 11．5统计学软件进行统计学处理。[结果]原代培养及传代培养显示兔骨髓间充质干细胞具有活跃的增殖倍增能力，并且8周内蛋白多糖和Ⅱ型胶原的含量的恢复实验组对比模型组增高明显，统计学显示差异有显著性意义。[结论]将TGF-β1干预下的兔间充质干细胞移植到退变椎间盘后可以在一定时间内增加蛋白多糖和Ⅱ型胶原的含量，从而延缓椎间盘退变。     

骨髓间充质干细胞向髓核细胞的转化

骨髓间充质干细胞具有多向分化潜能,在不同环境下可诱导分化为多胚层来源的细胞,如:骨细胞、软骨细胞等.椎间盘退变主要源于髓核细胞及细胞外基质的变化,髓核细胞为类软骨细胞,随着细胞生物工程技术和分子生物学的进展,利用骨髓间充质干细胞结合细胞载体可再生出组织工程化的髓核细胞,将其植入椎间盘,从而阻止和逆转椎间盘退变,为治疗椎间盘退变提供一条新途径.     

温敏性壳聚糖水凝胶支架联合骨髓间充质干细胞治疗兔膝关节软骨缺损

目的 制备壳聚糖/Ⅱ型胶原/聚乳酸复合水凝胶支架,以支架为骨髓间充质干细胞载体,评价修复兔膝关节软骨缺损的可行性.方法 将壳聚糖、Ⅱ型胶原、聚乳酸联合β-甘油磷酸钠盐制备复合水凝胶,检测凝胶形成时间、弹性模量及细胞相容性;制作新西兰兔关节软骨缺损模型,分为四组.空白组:正常软骨,未作任何处理;模型组:旷置骨软骨缺损作为...     

移植骨髓间充质干细胞对兔退变椎间盘髓核细胞凋亡的影响

目的 观察骨髓间充质干细胞(MSCs)移植对兔退变椎间盘髓核细胞凋亡的影响.方法 以各兔L2/3、L3/4、L4/5、L5/6节段分为正常组、退变组、成纤维细胞(SFs)移植对照组、MSCs移植治疗组.MSCs和SFs分别经绿色荧光蛋白(GFP)转染后,注射植入退变椎间盘的髓核.通过透射电镜观察退变椎间盘凋亡髓核细胞形态;用实时定量聚合酶链反应(PCR)检测退变组织中髓核细胞凋亡相关基因bcl-2和box mRNA的表达;免疫荧光法标记髓核细胞凋亡相关蛋白Caspase-3,并通过TUNEL法标记凋亡髓核细胞,激光共聚焦显微镜检测髓核细胞凋亡蛋白表达率和细胞凋亡比率.结果 透射电镜下,退变椎间盘中凋亡髓核细胞呈现出核染色质边集,空泡形成,核膜断裂,凋亡小体形成等变化.MSCs移植治疗组bcl-2 mRNA的表达量高于退变组和SFs移植对照组(P<0.05),bax mRNA的表达量与退变组差异无统计学意义(P>0.05).MSCs移植治疗组细胞凋亡率和Caspase-3表达率均高于正常组[细胞凋亡率分别为(16.75±2.14)%和(6.86±1.08)%;Caspase-3表达率分别为[(20.34±1.03)%和(6.09±0.77)%](P<0.05),低于退变组和SFs移植对照组[细胞凋亡率分别为(31.87±4.16)%和(29.02±2.16)%;Caspase-3表达率分别为(31.50±3.78)%和(30.20±4.93)%](P<0.05).结论 髓核细胞凋亡在椎间盘退变过程中起重要作用.MSCs移植能有效抑制椎间盘髓核细胞凋亡,延缓椎间盘退变过程.     

椎间盘生物学修复的研究进展

椎间盘生物学修复研究试图延缓或扭转椎间盘退变过程,椎间盘退变模型、干细胞移植、细胞因子注射、基因治疗和组织工程等是该领域的研究热点。椎间盘退变目前仍缺乏理想的动物模型,自然退变模型和人工诱导退变模型各有利弊;骨髓间充质干细胞是目前最有前景的移植候选细胞,新扩增方法的发明有望使其扩增成本大幅降低;各种细胞因子的实验性注射疗法均有文献报道,基因工程生产的细胞因子为该类研究的首选;壳聚糖等具备独特材料特性的三维空间网络状支架材料在椎间盘组织工程中颇具前景;椎间盘修复的治疗干预方式首选细针注射。最终具备可行性的临床生物学修复方法很可能是综合细胞移植、基因转染、细胞因子和组织工程等诸多治疗因素的综合方案。     

细胞移植治疗椎间盘退变的研究进展

椎间盘退变性疾病的发病率随着人口老龄化逐年增加,给个人和社会都带来巨大的负担.传统的治疗方式无论是保守治疗还是手术治疗都无法从根源上解决退变的问题.为减轻退变椎间盘内的炎性环境、减少髓核细胞凋亡,细胞移植为治疗椎间盘退变带来新的思路.通过将髓核细胞或多种来源的间充质干细胞植入退变的髓核内,可达到减缓椎间盘退变进程的目的...     

骨髓间充质干细胞结合藻酸盐治疗椎间盘退变的实验研究

目的观察骨髓间充质干细胞（Bone mesenchymal stem cell,BMSC）结合藻酸盐凝胶支架,治疗兔椎间盘退变的效果。方法将15只新西兰大白兔建立腰椎间盘退变模型,随机分为对照组、空白组和治疗组。体外培养兔BMSC,治疗组椎间隙注射BMSC结合藻酸盐凝胶支架,对照组注射藻酸盐凝胶,空白组注射生理盐水。应用核磁共振、免疫组化和生化分析,观察椎间盘退变的修复效果。结果治疗组影像学、病理组织学观察,以及蛋白多糖和Ⅱ型胶原的含量,均明显优于对照组和空白组,差异有统计学意义。结论 BMSC结合藻酸盐凝胶支架可用于治疗兔腰椎间盘退变。     

非接触式共培养体系对脐带间充质干细胞向类髓核细胞的诱导分化效应

目的探讨人脐带间充质干细胞向类髓核细胞的分化潜能,为椎间盘退变性疾病的生物学治疗探索新的细胞来源。方法取人正常足月产婴儿脐带及成人椎间盘,分离消化华通胶组织和髓核组织,收集培养脐带间充质干细胞及成人髓核细胞。利用带有插入层的Transwell 6孔培养板进行细胞非接触式共培养,细胞比例为1∶1,以脐带间充质干细胞单独培养作为对照组。共培养1周后,提取脐带间充质干细胞总RNA,利用Real-Time PCR检测其Ⅱ型胶原、蛋白多糖及SOX9基因的相对表达改变。结果成功分离提取脐带间充质干细胞;Real-Time PCR检测结果显示实验组脐带间充质干细胞Ⅱ型胶原、蛋白多糖和SOX9基因相对表达较对照组显著增加,差异有统计学意义（P〈0.01）。结论人脐带间充质干细胞能够被髓核细胞诱导分化为类髓核细胞,有可能为椎间盘退变性疾病的生物学治疗提供一种新的细胞来源。     

海藻酸钠复合多能诱导干细胞修复椎间盘研究

[目的]探讨海藻酸钠盐微球凝胶复合多能诱导干细胞(induced pluripotent stem cells, IPS)定向分化的髓核细胞对退变椎间盘修复作用。[方法] 50只新西兰大白兔分为5组,10只作为正常对照组,40只建立兔椎间盘退变模型,并随机分为4组,每组10只。模型组不行治疗,材料组注射不含髓核细胞的海藻酸钠盐微球凝胶材料,细胞组注射诱导分化的髓核细胞,联合组注射IPS定向分化的髓核细胞与海藻酸钠盐微球凝胶材料复合物,治疗8周后,采用组织学Mankin评分评估各组椎间盘软骨退变情况;采用免疫组化分析各组椎间盘组织蛋白多糖、Ⅱ型胶原和MMP3的表达水平。[结果]与细胞组比较,联合组兔椎间盘软骨退变改善最显著,各组组织学评分分别为:对照组(1.27±0.19)分,模型组(19.43±3.48)分,材料组(18.59±4.01)分,细胞组(13.11±3.81)分,联合组(5.90±2.01)分,差异有统计学意义(P0.05)。与细胞组比较,联合组兔椎间盘组织蛋白多糖和Ⅱ型胶原增加更显著,MMP3蛋白下调更显著,差异有统计学意义(P0.05)。[结论]海藻酸钠盐微球凝胶复合IPS定向分化的髓核细胞可显著改善椎间盘内环境,促进退变椎间盘组织修复。     

瘦素缺乏小鼠椎间盘退变的组织学观察

目的探讨瘦素在椎间盘退变中的可能作用。方法采用HE染色观察6月龄雄性ob/ob小鼠（瘦素缺乏小鼠）和野生型小鼠（C57BL小鼠）椎间盘的形态学;免疫组织化学检测Ⅱ型胶原、蛋白聚糖的表达;Real-time PCR检测Ⅱ型胶原、Ⅹ型胶原及蛋白聚糖的基因表达。结果与野生型小鼠相比,ob/ob小鼠椎间盘HE染色表现为椎间盘组织的胶原结构紊乱、髓核碎裂、椎间盘高度降低,免疫组化检测显示Ⅱ型胶原、蛋白聚糖表达减少,Real-time PCR检测显示Ⅱ型胶原、蛋白聚糖基因表达下调而Ⅹ型胶原基因表达上调,差异有统计学意义（P〈0.05）。结论活体内瘦素缺乏可能加速小鼠椎间盘退变。     

椎体终板损伤对兔椎问盘髓核Ⅰ、Ⅱ型胶原的影响

目的 观察椎体终板损伤对兔椎间盘髓核Ⅰ、Ⅱ型胶原的影响并探讨其机制.方法 4个月龄清洁级日本大白兔12只,完整取出40个包含终板的完整椎间盘(L2-L5),随机分为实验组和对照组,每组20个.实验组参考Daniel Haschtmann的方法建立终板损伤模型.椎间盘整体培养2周后,免疫组织化学方法观察椎间盘髓核中Ⅰ、Ⅱ型胶原的表达情况,并用HMIAS-2000图像分析系统进行半定量分析.结果 免疫组织化学染色显示:实验组椎间盘髓核Ⅰ型胶原的表达比对照组高;而Ⅱ型胶原的表达则比对照组低,差异均有统计学意义(P<0.05).结论 外伤致椎体终板损伤后会导致椎间盘髓核Ⅰ、Ⅱ型胶原的变化,继而加速椎间盘退行性变.     

Nucleus pulposus allograft retards intervertebral disc degeneration

Autogenous implantation of nucleus pulposus or nucleus pulposus cells that were activated by coculture retards intervertebral disc degeneration, but harvesting such grafts causes disc degeneration at the donor site. This study examined whether nucleus pulposus allografts similarly retard disc degeneration and whether such allografting induces immunologic rejection. Japanese White rabbits served as donors and recipients for allografts. Lumbar disc degeneration was induced by aspirating the nucleus pulposus. Two weeks later, intact nucleus pulposus or nucleus pulposus cells were injected and compared with a sham procedure and normal control. The recipients' discs were examined histologically and immunologically at intervals for 16 weeks. Discs receiving an intact nucleus pulposus showed the least degeneration, followed by discs receiving nucleus pulposus cells, both of which were better than no treatment. These findings correlated directly with the intensity of immunochemical staining for Type II collagen. Allogeneic grafts did not induce any appreciable host-versus-graft response. Injection of nucleus pulposus and nucleus pulposus cells retards intervertebral disc degeneration. However, injection of intact nucleus pulposus is more effective than injection of nucleus pulposus cells alone. The intercellular matrix plays an important, but poorly understood, role in preserving intervertebral discs.     

New strategies for disc repair: novel preclinical trials

Degeneration of lumbar intervertebral discs is a major cause of low back complaints, an irreversible occurrence with no currently available treatment. Furthermore, various surgical procedures can accelerate disc degeneration. On the other hand, recent experimental studies on disc cells have demonstrated an important role for the nucleus pulposus in preserving overall disc structure. The authors group has already found that nucleus pulposus cells activated annulus fibrous cells, and reinsertion of nucleus pulposus cells slowed further disc degeneration. We have designed three subsequent studies that were designed to examine further possibilities for clinical transplantation: (1) activation of nucleus pulposus cells by mesenchymal stem cells; (2) focus on the multilineage differentiation potential of mesenchymal stem cells as an alternative cell source for cell transplantation therapy of disc degeneration; (3) the possibility of a human nucleus pulposus cell line as a cell source for cell transplantation therapy. Activation of nucleus pulposus could be achieved by co-culture with autogenous mesenchymal stem cells allowed to have direct cellular interaction. This would be a useful clinical cell source. Induction of nucleus pulposus cells by autogenous mesenchymal stem cells also would be an important subject for a clinical trial. Clinical application of the cells derived from a human nucleus pulposus cell line is an important project to be undertaken in the near future.This Instructional lecture was presented at the 76th Annual Meeting of the Japanese Orthopaedic Association, May 2003     

The fate of transplanted xenogeneic bone marrow‐derived stem cells in rat intervertebral discs

Intervertebral disc degeneration is a major cause and a risk factor for chronic low back pain. The potential of using stem cells to treat disc degeneration has been raised. The aims of our study were to assess whether xenogeneic bone‐marrow derived stem cells could survive in a rat disc degeneration model and to determine which cell types, if any, survived and differentiated into disc‐like cells. Human bone‐marrow derived CD34⁺ (hematopoietic progenitor cells) and CD34^? (nonhematopoietic progenitor cells, including mesenchymal stem cells) cells were isolated, fluorescent‐labeled, and injected into rat coccygeal discs. The rats were sacrificed at day 1, 10, 21, and 42. Treated discs were examined by histological and immunostaining techniques and compared to control discs. The survival of transplanted cells was further confirmed with a human nuclear specific marker. Fluorescent labeled CD34^? cells were detected until day 42 in the nucleus pulposus of the injected discs. After 3 weeks these cells had differentiated into cells expressing chondrocytic phenotype (Collagen II and Sox‐9). In contrast, the fluorescent labeled CD34⁺ cells could not be detected after day 21. No fluorescence‐positive cells were detected in the noninjected control discs. Further, no inflammatory cells infiltrated the nucleus pulposus, even though these animals had not received immunosuppressive treatment. Our data provide evidence that transplanted human BM CD34^? cells survived and differentiated within the relative immune privileged nucleus pulposus of intervertebral disc degeneration. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:374–379, 2009     

Activation of rat nucleus pulposus cells by coculture with whole bone marrow cells collected by the perfusion method

Cell proliferation and matrix synthesis were compared for rat nucleus pulposus cells cocultured with mesenchymal stem cells (MSCs) or fresh whole bone marrow cells (BMCs), harvested by the perfusion or aspiration methods. Nucleus pulposus cells were isolated from tail intervertebral discs of F344/slc rats, and BMCs were obtained from femora. Proteoglycan synthesis, DNA synthesis, and aggrecan mRNA expression were measured. The level of transforming growth factor‐β in supernatants from the culture system was also measured. Cell number, aggrecan mRNA expression, and uptake of [³⁵S]‐sulfate and [³H]‐thymidine by nucleus pulposus cells cocultured with fresh whole BMCs all increased significantly compared with nucleus pulposus cells cocultured with MSCs. TGF‐β secreted by nucleus pulposus cells cocultured with fresh whole BMCs also significantly increased when compared with cocultures with MSCs. The perfusion method was superior to the aspiration method for preventing contamination of BMCs with peripheral red blood cells and lymphocytes, which may cause an autoimmune response in the disc. In conclusion, we suggest that fresh whole BMCs harvested by the perfusion method are more effective for increasing the proliferative and matrix synthesis capacity of nucleus pulposus cells. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:222–228, 2009     

水凝胶再生修复退变椎间盘的研究进展

目的总结生物材料水凝胶治疗椎间盘退变的研究进展,探讨水凝胶再生修复退变椎间盘的临床应用潜能。方法广泛查阅国内外有关水凝胶修复退变椎间盘尤其是髓核组织的研究文献,并进行总结和分析。结果水凝胶与髓核组织具有相似特性,在退变椎间盘再生修复中扮演重要角色,主要可体现在人工髓核假体、以水凝胶为载体的细胞治疗、非细胞治疗和组织工程修复。结论水凝胶作为生物材料广泛应用于椎间盘的再生修复治疗,为治疗椎间盘退变提供了新方向。     

两种骨水泥渗漏对椎间盘影响的实验研究

目的 探讨椎体成形术时骨水泥渗漏是否会引起椎间盘退变，以及椎间盘退变程度与骨水泥类型是否相关。方法 选用8只成年家犬，以每只犬L2-3、L3-4、L4-5椎间盘为实验对象，随机分为对照组、聚甲基丙烯酸甲酯（polymethylmethacrylate，PMMA）与磷酸钙骨水泥（calcium phosphate cement，CPC）3组。对照组仅行椎间盘穿刺，不注入任何物质，PMMA组及CPC组均各向椎间盘注入0．1ml骨水泥。术前及术后24周摄正、侧位X线片，计算椎间盘高度指数百分数（disc height index percentage，DHIP）。术后24周行MR检查，计算MRI指数。组织学检查参照Masuda标准对椎间盘退变程度评分并分析。结果 术后24周X线片显示对照组椎间隙无狭窄，病理学检查未见椎间盘退变。PMMA、CPC组椎间盘MRI显示：椎间隙有狭窄，R加权像髓核信号不同程度降低且不均一，其相对高信号区面积减小，髓核形态不规则，纤维环与髓核界限不清。组织学检查显示髓核细胞数量不同程度减少，空泡变小。髓核的细胞外基质不同程度压缩，纤维环断裂或扭转。3组DHIP、MRI指数、组织学评分的差异均有统计学意义（P〈0.01）。结论 PMMA、CPC注入椎间盘会导致椎间盘退变，PMMA所致椎间盘退变较CPC更为严重.