Moutos Franklin T, Glass Katherine A, Compton Sarah A, Ross Alison K, Gersbach Charles A, Guilak Farshid, Estes Bradley T
Cytex Therapeutics, Durham, NC 27705;
Department of Orthopedic Surgery, Washington University, St. Louis, MO 63110; Shriners Hospitals for Children, St. Louis, MO 63110; Department of Biomedical Engineering, Duke University, Durham, NC 27708.
Proc Natl Acad Sci U S A. 2016 Aug 2;113(31):E4513-22. doi: 10.1073/pnas.1601639113. Epub 2016 Jul 18.
Biological resurfacing of entire articular surfaces represents an important but challenging strategy for treatment of cartilage degeneration that occurs in osteoarthritis. Not only does this approach require anatomically sized and functional engineered cartilage, but the inflammatory environment within an arthritic joint may also inhibit chondrogenesis and induce degradation of native and engineered cartilage. The goal of this study was to use adult stem cells to engineer anatomically shaped, functional cartilage constructs capable of tunable and inducible expression of antiinflammatory molecules, specifically IL-1 receptor antagonist (IL-1Ra). Large (22-mm-diameter) hemispherical scaffolds were fabricated from 3D woven poly(ε-caprolactone) (PCL) fibers into two different configurations and seeded with human adipose-derived stem cells (ASCs). Doxycycline (dox)-inducible lentiviral vectors containing eGFP or IL-1Ra transgenes were immobilized to the PCL to transduce ASCs upon seeding, and constructs were cultured in chondrogenic conditions for 28 d. Constructs showed biomimetic cartilage properties and uniform tissue growth while maintaining their anatomic shape throughout culture. IL-1Ra-expressing constructs produced nearly 1 µg/mL of IL-1Ra upon controlled induction with dox. Treatment with IL-1 significantly increased matrix metalloprotease activity in the conditioned media of eGFP-expressing constructs but not in IL-1Ra-expressing constructs. Our findings show that advanced textile manufacturing combined with scaffold-mediated gene delivery can be used to tissue engineer large anatomically shaped cartilage constructs that possess controlled delivery of anticytokine therapy. Importantly, these cartilage constructs have the potential to provide mechanical functionality immediately upon implantation, as they will need to replace a majority, if not the entire joint surface to restore function.
对整个关节表面进行生物修复是治疗骨关节炎中软骨退变的一项重要但具有挑战性的策略。这种方法不仅需要符合解剖尺寸且具有功能的工程化软骨,而且关节炎关节内的炎症环境也可能抑制软骨生成并导致天然软骨和工程化软骨的降解。本研究的目的是利用成体干细胞构建具有解剖形状、功能的软骨构建体,使其能够可调谐且可诱导地表达抗炎分子,特别是白细胞介素-1受体拮抗剂(IL-1Ra)。用三维编织聚(ε-己内酯)(PCL)纤维制成两种不同构型的大型(直径22毫米)半球形支架,并接种人脂肪来源干细胞(ASC)。将含有增强绿色荧光蛋白(eGFP)或IL-1Ra转基因的强力霉素(dox)诱导型慢病毒载体固定到PCL上,以便在接种时转导ASC,构建体在软骨形成条件下培养28天。构建体表现出仿生软骨特性和均匀的组织生长,同时在整个培养过程中保持其解剖形状。在用dox进行可控诱导后,表达IL-1Ra的构建体产生了近1μg/mL的IL-1Ra。用白细胞介素-1处理显著增加了表达eGFP的构建体条件培养基中的基质金属蛋白酶活性,但在表达IL-1Ra的构建体中未增加。我们的研究结果表明,先进的纺织制造技术与支架介导的基因递送相结合,可用于组织工程构建大型解剖形状的软骨构建体,实现抗细胞因子治疗的可控递送。重要的是,这些软骨构建体在植入后有可能立即提供机械功能,因为它们需要替换大部分(如果不是整个)关节表面以恢复功能。