脱细胞血管基质制备及体内外生物相容性

背景:利用脱细胞血管基质作为血管支架具有以下优点:脱细胞血管基质保留了自然血管的复杂三维结构;脱细胞基质表面的生长因子和结构域有利于细胞的黏附和浸润。目的:制备脱细胞血管基质并对其体内外生物相容性进行评价。方法:采用胰蛋白酶、Triton X-100逐步处理猪颈动脉制备脱细胞血管基质。采用皮下植入实验、急性毒性实验和体外细胞毒性实验等评价其生物相容性。结果与结论:脱细胞基质材料具有良好的化学稳定性,未释放对红细胞产生破坏溶解作用的有害元素,未引起急性溶血反应,对细胞的生长无毒性影响。脱细胞基质材料在动物体内植入后早期有较多炎性细胞浸润,到实验观察的后期无明显炎性细胞浸润,脱细胞基质内可见成纤维细胞。另外,脱细胞基质材料对周边组织未产生毒性作用,伤口Ⅰ期愈合。同时组织学切片显示:支架材料与周边组织相容性好,未产生排斥反应。说明脱细胞基质材料在动物体内具有很好的生物相容性。     

脱细胞基质软骨支架的制备

背景：脱细胞基质材料去除了天然材料中的细胞成分,保留了基质成分,有效降低了天然材料的免疫原性,同时能够保持材料的机械强度。 目的：拟利用洗脱方法去除兔肋软骨中的细胞基质,制备天然生物支架材料。 方法：取新西兰大白兔肋软骨,清除周围组织后随机分组处理,以未经处理的肋软骨作为正常对照组;48 h处理组以去污剂-酶化学消化48 h;96 h处理组以去污剂-酶化学消化96 h,3组均通过苏木精-伊红染色及电镜观察脱细胞效果。同时收集诱导第7天的兔骨髓间充质干细胞3×109 L-1,与同种异体肋软骨脱细胞基质体外复合培养,于第3,7天取复合物行电镜观察细胞在脱细胞基质表面的黏附生长情况。 结果与结论：新鲜肋软骨标本每个软骨陷窝内均有排列紧密的二三个软骨细胞,去污剂-酶化学消化后软骨陷窝内的细胞逐渐脱失,至消化处理96 h后,软骨陷窝内的细胞完全脱失。共培养第3天时,脱细胞基质表面有大量骨髓间充质干细胞分布,细胞为多角形,有伪足伸出,锚定在基质表面,部分区域可见细胞在基质表面增殖分裂;第7天时,脱细胞基质表面大部分均为细胞覆盖,细胞呈扁平状,有多个足突充分伸展,细胞之间互相连接,分泌大量细胞外基质沉积在基质表面,呈冰霜样改变,表明制备的脱细胞基质具有良好的细胞相容性。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

兔肋软骨脱细胞基质的制备

背景：研究表明新西兰兔软骨组织可作为组织工程支架材料,其中关节软骨及耳软骨的脱细胞基质的研究较多,但采用肋软骨作为组织工程软骨支架的研究较少。 目的：制备新西兰兔肋软骨脱细胞基质,探讨天然软骨支架作为组织工程支架的可行性。 方法：用联合去垢剂-酶法获得软骨支架,根据脱细胞过程中Triton X-100第2次处理时间0,24,48,96 h分为4组。脱细胞完毕后各组支架固定行扫描电镜采集图像观察计算支架孔隙率、孔径长度,并对支架进行苏木精-伊红染色、甲苯胺蓝及Ⅱ型胶原免疫组织化学染色,并将脱细胞支架植入异体新西兰兔皮下观察其相容性。 结果与结论：兔肋软骨脱细胞基质呈乳白色,大小均一,染色示支架结构完整,仍保存大量酸性黏多糖及Ⅱ型胶原成分,扫描电镜观察经一定时间的脱细胞处理后可得到结构完整,孔隙均匀的天然软骨支架,其孔隙率为(61.31±8.45) %;孔径长度为(32.80±5.15) μm,符合正态性分布,各组脱细胞支架植入异体新西兰兔皮下7 d后生物相容性良好,周围软组织无明显充血、化脓等炎症排斥反应出现。结果显示,兔肋软骨脱细胞支架具有良好的基质组成,有较完整、均匀的孔隙结构及孔径分布,可作为组织工程支架材料。     

应用猪主动脉脱细胞基质制备新型组织工程血管支架:生物相容性及力学性能评价(英文)

背景:组织工程血管构建的关键依赖于理想的支架。猪血管作为组织工程血管构建材料已有广泛应用,但其较高的免疫原性及较差的力学强度限制了该材料作为组织工程支架的应用。目的:应用猪主动脉脱细胞基质制备一种新的具有良好机械性能及生物相容性的组织工程血管支架。方法:对猪主动脉进行脱细胞处理和热交联改性制备脱细胞血管基质支架,采用苏木精-伊红染色及生物力学分析评估其脱细胞效果及血管基质的力学性能。将人脐静脉血管内皮细胞接种于脱细胞血管基质支架中进行体外培养,评估其生物相容性。结果与结论:用1%的TritonX-100溶液处理猪主动脉84h可完全脱除血管细胞,同时不破坏血管基质结构;经真空下120℃热交联处理12h,脱细胞基质的拉伸断裂强度得到明显提高,达到1.70MPa。在该改性血管基质支架上接种人脐带静脉内皮细胞体外培养7d,扫描电镜显示内皮细胞呈现典型的血管内皮层状结构。表明猪主动脉经过脱细胞处理能够维持血管基质完整,冷冻干燥和真空热交联处理可有效提高其拉伸强度,且对血管内皮细胞具有良好的相容性。     

兔骨髓间充质干细胞与异体脱细胞耳软骨支架的体外复合*

背景：耳软骨作为脱细胞基质可选择的支架,进行脱细胞处理可去除了软骨细胞的抗原性,从而与种子细胞具有良好的相容性。 目的：体外提取、培养兔骨髓基质干细胞,并与异体脱细胞耳软骨支架复合,观察其生物相容性。 方法：提取兔骨髓间充质干细胞行体外培养,诱导为软骨细胞,以胰蛋白酶-曲拉通联合法获得脱细胞软骨支架,将两者于体外复合,10 d后复合支架固定行组织学染色及扫描电镜观察。 结果与结论：兔骨髓间充质干细胞体外诱导14 d可形成软骨细胞,Ⅱ型胶原免疫细胞化学示胞浆呈棕黄色;兔耳软骨脱细胞基质呈乳白色,组织学染色及扫描电镜观察示经脱细胞后支架孔隙均匀,结构完整,仍保存大量酸性黏多糖及胶原成分。其孔径长度(33.70±4.33) μm,孔隙率(65.23±7.35)%。 复合支架组织学染色及扫描电镜示两者黏附良好,并伴有多量基质分泌。说明兔骨髓间充质干细胞诱导为软骨细胞与异体脱细胞耳软骨有良好的生物相容性。     

脱细胞血管组织基质的制备和平滑肌细胞的种植

目的组织工程血管的研制成功将为先天性心脏病外科提供一种新的理想的修补材料,本文研究血管脱细胞组织基质的制备,平滑肌细胞的体外培养和种植方法.方法取成年羊胸主动脉,用胰酶消化去除细胞成分,保存弹性蛋白和胶原蛋白,获得血管脱细胞组织基质,经点状注射法,种植体外培养的小牛平滑肌细胞.结果羊主动脉经脱细胞处理,得到的组织基质最大负载下降20%,最大伸长无显著改变;脱细胞组织基质的胶原蛋白含量与新鲜主动脉相似;基质的纤维结构完整,为网状或多孔状;种植的小牛平滑肌细胞生长良好.结论采用多步骤方法获得的血管脱细胞组织基质可用作为制备组织工程血管的支架,适宜于血管平滑肌细胞的生长.     

牛心包脱细胞支架的制备研究

组织工程支架材料是构建组织工程器官或组织的重要基础,天然脱细胞基质由于具有其优良特性而成为理想的支架材料。本研究采用胰酶去污剂法、冻融去污剂24 h法、冻融去污剂48 h法、冻融核酸酶法和去污剂核酸酶法等5种方法对牛心包组织进行脱细胞处理。通过HE染色、扫描电镜观察、含水量检测、力学检测、DNA含量检测和细胞毒性试验,判断不同脱细胞方法的脱细胞效果及其对牛心包基质的影响,从而筛选出对牛心包进行脱细胞的最佳方法。结果显示冻融后去污剂24 h法可以完全脱除牛心包的细胞成分,同时细胞外基质和力学特性保持完好,细胞毒性低,且经济实惠,是制备牛心包脱细胞支架的较好方法。     

脱细胞猪膀胱支架的构建

文题释义： 脱细胞：生物移植或修补材料制备过程中常用到脱细胞方法,脱细胞能很好的保留组织的成分,降低移植或修补后的免疫原性,同时保持良好的机械性能,在临床上得到较为广泛的应用。 猪膀胱支架：利用不同的脱细胞方法去除猪膀胱组织中的细胞后制备为猪膀胱支架,既保留了细胞外基质的完整性,又可以降低移植后排斥反应,为进一步的对组织工程支架材料的研究奠定了可行的基础。 背景：膀胱修补术是目前临床上治疗膀胱缺损的主要方法之一,同源性组织因各种因素的影响来源较少,组织工程膀胱脱细胞基质受到人们越来越多的关注。猪膀胱脱细胞外基质来源广泛,具备天然的细胞外支架结构,成为组织工程膀胱替代材料研究的热点。 目的：研究脱细胞猪膀胱作为组织工程支架材料的可行性。 方法：取新鲜的猪膀胱,联合液氮冻融、十二烷基硫酸钠、胰蛋白酶脱细胞方法制猪膀胱无细胞基质。按不同脱细胞方法分组：①正常对照组：不做任何处理;②实验组：0.6%胰蛋白酶+5%十二烷基硫酸钠(pH 8.0);③脱细胞对照组：分别用0.75%胰蛋白酶(pH 8.0)、1%胰蛋白酶(pH 8.0)、5%十二烷基硫酸钠(pH 7.6)或10%十二烷基硫酸钠(pH 7.6)处理。通过苏木精-伊红染色和VG染色、DNA定量、α-Gal抗原检测,观察猪膀胱脱细胞效果。 结果与结论：苏木精-伊红染色显示实验组猪膀胱细胞成分已基本去除;VG染色显示实验组完整保留了猪膀胱组织的细胞外基质成分;实验组的DNA残留量仅为(49.84±30.13) μg/g,显著低于几个脱细胞对照组(P < 0.05);同时其α-Gal抗原残留也明显低于脱细胞对照组。提示：应用0.6%胰蛋白酶+5%十二烷基硫酸钠处理猪膀胱,在完整保留猪膀胱组织细胞外基质的同时,可有效去除其细胞成分,为构建脱细胞猪膀胱支架提供一定参考价值。 ORCID: 0000-0003-1004-7390(李芹) 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

人包皮组织脱细胞基质的制备与生物相容性

目的 制备人包皮组织脱细胞基质移植物（AMGs）,探讨其浸提液对兔尿道黏膜细胞毒性。方法 制备人包皮组织脱细胞基质后,通过Masson 染色观察脱细胞后基质的表征,扫描电子显微镜观察其孔径大小。体外培养尿道黏膜细胞,采用免疫荧光鉴定其AE3表达。 尿道黏膜细胞与AMGs 基质浸提液体外共培养,MTT法检测 AMGs 浸提液对 尿道黏膜细胞毒性。结果 Masson 染色显示细胞去除干净,只有胶原蛋白构成的支架,扫描电镜显示支架的孔径为20～50 μm,分布均匀,形态良好。适当浓度的AMGs 基质浸提液对尿道黏膜细胞无明显毒性。结论 人包皮组织脱细胞基质为理想的 AMGs 支架材料,制备的 AMGs 材料细胞毒性小,有一定的实用价值。     

组织工程血管基质的制备与改性

目的：完全脱除猪胸主动脉细胞，对脱细胞血管基质进行改性，增强基质的力学强度，制备组织工程血管支架材料。方法：取家猪的新鲜去除外膜胸主动脉20根，随机分成4组，分别采用胰蛋白酶、TritonX-100及十二烷基硫酸钠（SDS）作为脱细胞试剂对猪胸主动脉进行脱细胞处理，并对脱细胞后的血管基质进行改性，采用HE染色、弹力纤维染色、力学性能测试，以评价脱细胞效果以及材料的力学性能。结果：采用1％TritonX-100单独作用84h既能完全脱除细胞，同时又可完整保留血管基质的三维结构，对胶原纤维、弹力纤维的损伤小，是一种较理想的脱细胞方法。对脱细胞后的基质进行冷冻干燥及真空热交联处理，能有效提高材料的机械强度，冷冻干燥24h后真空120℃下热交联处理12h所获得的材料的机械强度最好，断裂强度可达到1．70MPa。结论：以脱细胞血管基质经冷冻干燥和真空热交联处理后，可以作为血管组织工程的支架材料。     

动物血管脱细胞方法及细胞外基质材料评价研究

采用独立设计的反复冻融方法,去除兔颈总动脉中的血管细胞,对所获得的细胞外基质进行组织、生化、力学等分析。在分离兔颈总动脉后,首先用低渗缓冲液处理,然后经低温反复冻融,最后用非离子型去污剂处理。所得的支架行组织染色和扫描电镜分析,显示基质的微观结构;荧光染色和基因组DNAPCR分析,检测细胞DNA残留;分别行羟脯氨酸定量分析和轴向拉伸强度分析,检测胶原蛋白和血管生物力学性能的变化;支架没有明显的细胞毒性,溶血率低于医用材料的标准;支架随时间缓慢降解。种植兔的骨髓干细胞,研究细胞在支架上的粘附生长能力。应用本方法能彻底去除血管细胞,没有细胞碎片和DNA的残留,并保留了较完整的细胞外基质和力学性能,具有开放的大孔径结构,细胞生物相容性好,是一种理想的组织工程血管支架材料。     

Tissue engineering small-diameter vascular grafts: preparation of a biocompatible porcine ureteric scaffold

This study aimed to investigate a biocompatible, biomechanically functional, small-diameter (<6 mm) scaffold for tissue engineering a vascular graft using acellular porcine ureters. Porcine ureters were decellularized and sterilized using sequential treatment with hypotonic Tris buffer, sodium dodecyl sulphate 0.1% w/v (plus proteinase inhibitors), nuclease solution (RNase and DNase), and peracetic acid. The scaffold was compared with fresh ureter according to histology, immunocytochemistry, quantitative determination of alpha-galactosyl (alpha-Gal), and biochemistry. The biomechanical properties of the scaffold were compared with those of fresh ureters and human saphenous vein. The biocompatibility of decellularized ureters was assessed using in vitro contact and extract cytotoxicity tests. The in vivo biocompatibility was investigated using a mouse model. The histioarchitecture of the acellular ureteric scaffolds was preserved with some loss of basement membrane proteins while showing no evidence of cellularity. There was no evidence of residual alpha-Gal epitope present in acellular ureter. The ultimate tensile strength, compliance, and burst pressures of the acellular ureters were not compromised, compared with fresh tissues (p > 0.05), and the results compared favorably with fresh human saphenous vein samples (p > 0.05). The decellularized scaffolds were shown to be biocompatible with porcine smooth muscle and endothelial cells in vitro. One month after subcutaneous implantation in mice, explants were analyzed immunohistochemically using anti-CD3, Factor VIII, F4/80 (macrophage), and alpha-smooth muscle actin antibodies. The fresh tissue controls had a significantly thicker capsule (of inflammatory cells and fibrous tissue) than decellularized implants (p < 0.05). Decellularized explants were infiltrated with a combination of fibroblast-like cells and macrophages, indicating a healthy repair process. This study has demonstrated the potential of acellular porcine ureteric scaffolds in tissue engineering small-diameter living vascular grafts.     

Altered structural and mechanical properties in decellularized rabbit carotid arteries

Recently, major achievements in creating decellularized whole tissue scaffolds have drawn considerable attention to decellularization as a promising approach for tissue engineering. Decellularized tissues are expected to have mechanical strength and structure similar to the native tissues from which they are derived. However, numerous studies have shown that mechanical properties change after decellularization. Often, tissue structure is observed by histology and electron microscopy, but the structural alterations that may have occurred are not always evident. Here, a variety of techniques were used to investigate changes in tissue structure and relate them to altered mechanical behavior in decellularized rabbit carotid arteries. Histology and scanning electron microscopy revealed that major extracellular matrix components were preserved and fibers appeared intact, although collagen appeared looser and less crimped after decellularization. Transmission electron microscopy confirmed the presence of proteoglycans (PG), but there was decreased PG density and increased spacing between collagen fibrils. Mechanical testing and opening angle measurements showed that decellularized arteries had significantly increased stiffness, decreased extensibility and decreased residual stress compared with native arteries. Small-angle light scattering revealed that fibers had increased mobility and that structural integrity was compromised in decellularized arteries. Taken together, these studies revealed structural alterations that could be related to changes in mechanical properties. Further studies are warranted to determine the specific effects of different decellularization methods on the structure and performance of decellularized arteries used as vascular grafts.     

Effect of laser perforation on the remodeling of acellular matrix grafts

Autologous cells migrate only slightly into acellular matrix grafts. This study was carried out in small-diameter, allogeneic matrix grafts to investigate the effects on cell repopulation and remodeling caused by increased wall porosity induced by laser perforation. Allogeneic ovine carotid arteries were decellularized by dye-mediated photooxidation (Photofix). Matrix grafts (10 cm x 4 mm i.d.) were perforated with holes of 50 microm diameter at a density of 50 holes/cm(2) using a Ti-sapphire laser. The grafts were implanted in the carotid arteries of 10 sheep and were compared to nonperforated grafts implanted contralaterally. The prostheses were retrieved after 6 weeks or 3 or 6 months following implantation and were evaluated by histologic examination, immunohistochemical staining, and scanning electron microscopy. All grafts, except one of the perforated specimens, remained patent. Perforated implants, examined at 6 weeks, showed faster recellularization with endothelial cells than did the corresponding contralateral controls. Perforated grafts, examined at 6 months, showed a significantly thicker neointima and clear signs of neovascularization: endothelial cells, basal lamina, elastic fibers, circular and longitudinally orientated smooth muscle cells in comparison to nonperforated specimens. Repopulation of the decellularized matrix with host cells was higher in the perforated than in the nonperforated prostheses. These results suggest that the increased matrix porosity induced by laser perforation promotes graft remodeling and reconstitution with host cells.     

新型脱细胞骨基质材料的制备及理化评估

背景：传统的结构性天然骨脱细胞的方法存在许多不足之处。 目的：用新的理化方法对结构性骨块进行脱细胞处理制作新型骨支架材料的可行性,并检测其理化性能。 方法：以股骨头负重区结构性骨块为原料,高压水枪冲洗,继而利用Triton-100、脱氧胆酸钠等进行脱细胞等理化处理,制备新型脱细胞骨基质材料,并对支架进行大体、组织学、扫描电镜、Micro-CT观察、生物力学等相关检测。 结果与结论：新型脱细胞骨基质材料保留了骨的细胞外基质成分,脱细胞彻底,扫描电镜及Micro-CT观察显示支架具备三维多孔网状结构系统,具有天然骨的孔径和孔隙率;生物力学测试脱细胞组支架的弹性模量为(552.56±58.92) MPa,强度为(11.34±3.49) MPa,与新鲜骨的弹性模量及强度比较,差异无显著性意义(P > 0.05),可作为骨组织工程支架的良好载体。     

Development and evaluation of a novel decellularized vascular xenograft

Although autogenous saphenous vein remains the standard for coronary and infrapopliteal bypass, many patients do not have a suitable vein. Attempts at developing a small-caliber vascular graft have failed largely due to occlusion, neointimal hyperplasia, or aneurismal degradation. We have designed and characterized a novel small-caliber vascular xenograft that may overcome these failure modes. To reduce immune reactions, porcine common carotid arteries were decellularized by enzymatic and detergent treatments. Histology and electron microscopic examination showed complete removal of cellular components while the extracellular matrix structure remained intact. To reduce thrombogeneity, decellularized vascular grafts were covalently linked with heparin. The efficiency of heparin linkage was demonstrated with toluidine blue staining and the antithrombogeneity of the heparin-treated grafts was demonstrated with a clot time test. Mechanical testing of the graft was performed. Decellularized-heparin-treated grafts were similar in compliance to fresh vessels and burst testing showed grafts to withstand pressures exceeding 10 times physiologic blood pressure. There was no difference in suture retention strength between fresh vessels and decellularized-heparin-treated grafts. Decellularized, heparinized grafts were implanted in dogs as carotid artery bypass grafts and showed smooth muscle cells densely populating the wall, and endothelial cells lining the lumen by two months. This study provides a new strategy to develop a small-caliber vascular graft with excellent mechanical properties, antithrombogeneity, and tissue compatibility.     

The use of air-flow impedance to control fiber deposition patterns during electrospinning

Electrospun non-woven structures have the potential to form bioresorbable vascular grafts that promote tissue regeneration in situ as they degrade and are replaced by autologous tissue. Current bioresorbable grafts lack appropriate regeneration potential since they do not have optimal architecture, and their fabrication must be altered by the manipulation of process parameters, especially enhancing porosity. We describe here an air-impedance process where the solid mandrel is replaced with a porous mandrel that has pressurized air exiting the pores to impede fiber deposition. The mandrel design, in terms of air-flow rate, pore size, and pore distribution, allows for control over fiber deposition and scaffold porosity, giving greater cell penetration without a detrimental loss of mechanical properties or structural integrity.     

脱细胞血管基质材料同种异体移植10个月研究*☆

背景：异体血管移植之所以至今未能在临床应用,关键是异体组织抗原性排斥反应的难题未能得到解决。 目的：制备动脉脱细胞血管基质,探讨脱细胞血管异体移植的可行性。 方法：采用不同去垢剂(1%Triton X-100、1%SDS)多步骤对犬血管进行脱细胞处理,通过组织学和力学观测,建立犬动脉血管脱细胞的方法;并进行脱细胞血管的异体移植。 结果与结论：经胰蛋白酶、低渗溶液和去垢剂Triton X-100、SDS等多步骤处理,犬颈总动脉血管的细胞基本脱除,细胞外基质保持完好,血管的弹性、韧性保存较好;用该法制备的犬颈总动脉(直径约4.0 mm)进行异体移植,经10个月观察,4/5通畅。提示经去垢剂Triton X-100、SDS加低渗溶液、胰蛋白酶和蛋白酶抑制剂处理的多步法,可以脱除血管的细胞成分,细胞外基质和力学特性保持完好,是一种较好的方法;用该法制备的犬颈总动脉可以直接进行异体移植,是一可选择的血管移植材料。 关键词：动脉血管;犬;脱细胞;同种异体移植;血管基质 doi:10.3969/j.issn.1673-8225.2012.12.014