Nagelli Christopher V, De La Vega Rodolfo E, Coenen Michael, De Padilla Consuelo Lopez, Panos Joseph A, Tovar Alejandro, Müller Sebastian A, Evans Christopher H
Musculoskeletal Gene Therapy Laboratory, Department of Physical Medicine and Rehabilitation, Mayo Clinic, Rochester, MN, USA.
Rehabilitation Medicine Center, Department of Physical Medicine and Rehabilitation, Mayo Clinic, Rochester, MN, USA.
Osteoarthr Cartil Open. 2022 Jun;4(2). doi: 10.1016/j.ocarto.2022.100257. Epub 2022 Mar 26.
To evaluate a single-step, gene-based procedure for repairing osteochondral lesions.
Osteochondral lesions were created in the patellar groove of skeletally mature rabbits. Autologous bone marrow aspirates were mixed with adenovirus vectors carrying cDNA encoding green fluorescent protein (Ad.GFP) or transforming growth factor-β (Ad.TGF-β) and allowed to clot. The clotted marrow was press-fit into the defects. Animals receiving Ad.GFP were euthanized at 2 weeks and intra-articular expression of GFP examined by fluorescence microscopy. Animals receiving Ad.TGF-β were euthanized at 3 months and 12 months; repair was compared to empty defects using histology and immunohistochemistry. Complementary experiments assessed transgene expression and chondrogenesis in marrow clots and fibrin gels. In a subsequent pilot study, repair at 3 months using a fibrin gel to encapsulate Ad.TGF-β was evaluated.
At 2 weeks, GFP expression was seen at variable levels within the cartilaginous lesion. At 3 months, there was no statistically significant improvement (p > 0.05) in healing of lesions receiving Ad.TGF-β and variability was high. At 12 months, there were still no significant difference (p > 0.05) between the empty defects and those receiving Ad.TGF-β in the overall, cartilage, and bone scores. Variability was still high. In vitro experiments suggested that variability reflected variable transduction efficiency and chondrogenic activity of the marrow clots; using fibrin gels instead of marrow may address this issue but more research is needed.
This approach to improving the repair of osteochondral lesions needs further refinement to reduce variability and provide a more robust outcome.
评估一种基于基因的单步修复骨软骨损伤的方法。
在骨骼成熟的兔髌沟中制造骨软骨损伤。将自体骨髓抽吸物与携带编码绿色荧光蛋白的互补DNA（Ad.GFP）或转化生长因子-β（Ad.TGF-β）的腺病毒载体混合并使其凝结。将凝结的骨髓压入缺损处。接受Ad.GFP的动物在2周时实施安乐死，并通过荧光显微镜检查关节内GFP的表达。接受Ad.TGF-β的动物在3个月和12个月时实施安乐死；使用组织学和免疫组织化学将修复情况与空白缺损进行比较。补充实验评估了骨髓凝块和纤维蛋白凝胶中的转基因表达和成软骨作用。在随后的一项初步研究中，评估了使用纤维蛋白凝胶包裹Ad.TGF-β在3个月时的修复情况。
在2周时，在软骨损伤内可见不同水平的GFP表达。在3个月时，接受Ad.TGF-β的损伤愈合情况没有统计学上的显著改善（p>0.05），且变异性很高。在12个月时，空白缺损与接受Ad.TGF-β的缺损在总体、软骨和骨评分方面仍无显著差异（p>0.05）。变异性仍然很高。体外实验表明，变异性反映了骨髓凝块的转导效率和成软骨活性的差异；使用纤维蛋白凝胶而非骨髓可能解决这个问题，但还需要更多研究。
这种改善骨软骨损伤修复的方法需要进一步优化，以降低变异性并提供更可靠的结果。
