Histone-targeted gene transfer of bone morphogenetic protein-2 enhances mesenchymal stem cell chondrogenic differentiation.
Histone-targeted gene transfer of bone morphogenetic protein-2 enhances mesenchymal stem cell chondrogenic differentiation.
复制标题
骨形态发生蛋白 2 的组蛋白靶向基因转移可增强间充质干细胞软骨形成分化。
DOI：
10.1016/j.actbio.2018.02.021
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发表时间：
2018
影响因子：
9.7
通讯作者：
Sullivan,MillicentO
中科院分区：
文献类型：
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作者：
Munsell,ErikV;Kurpad,DeepaS;Freeman,TheresaA;Sullivan,MillicentO
创伤性损伤后的骨骼组织再生涉及复杂的生长因子信号级联，其指导骨折内的间充质干细胞（MSC）的分化。这些因子受控和局部表达的必要性凸显了基因治疗作为骨修复的一种有前途的治疗选择可能发挥的作用。然而，谈判有效的细胞内运输和核递送的纳米载体系统的设计代表了一个重大挑战。最近的研究强调了组蛋白尾部序列在指导核递送和激活DNA转录中的作用。我们先前建立了在非病毒纳米载体内重现这些天然组蛋白尾部活性的能力，通过逆行囊泡运输有效导航到细胞核来改善基因转移和表达。在此，我们证明，与标准的聚合物转染试剂相比，组蛋白靶向导致MSC在6天内成骨形态发生蛋白-2（BMP-2）表达增加了104倍。这种提高的表达增强了软骨形成，这是骨折愈合的重要第一步。重要的是，软骨特异性蛋白表达的显着增强触发组蛋白靶向基因转移，与等量的重组BMP-2蛋白治疗的反应相比。事实上，重组BMP-2需要增加100倍才能达到类似的软骨形成基因和蛋白表达水平。使用组蛋白靶向实现的分化增强部分是通过转录因子表达的增加实现的，其功能是驱动MSC软骨形成。这些新的研究结果表明，组蛋白靶向基因转移策略的效用，使骨再生application.Statement的significanceThis贡献的显着限制，在骨再生应用的非病毒基因转移，通过利用一种新的组蛋白靶向细胞触发交付的方法，诱导成骨BMP-2的表达与骨修复的启动一致。在修复过程中，增殖的MSC响应一系列复杂的生长因子信号，这些信号引导它们沿着成熟骨形成所必需的细胞谱系分化。尽管这些MSC是细胞有丝分裂期间增强转染的理想靶点，但几乎没有非病毒递送方法能够使这种效果最大化。因此，这一贡献旨在利用我们的组蛋白靶向纳米载体设计策略来刺激BMP-2基因转移到分裂的MSC中。这种基于基因的方法导致显著增强的MSC软骨形成，这是骨组织修复的重要第一步。
Skeletal tissue regeneration following traumatic injury involves a complex cascade of growth factor signals that direct the differentiation of mesenchymal stem cells (MSCs) within the fracture. The necessity for controlled and localized expression of these factors has highlighted the role gene therapy may play as a promising treatment option for bone repair. However, the design of nanocarrier systems that negotiate efficient intracellular trafficking and nuclear delivery represents a significant challenge. Recent investigations have highlighted the roles histone tail sequences play in directing nuclear delivery and activating DNA transcription. We previously established the ability to recapitulate these natural histone tail activities within non-viral nanocarriers, improving gene transfer and expression by enabling effective navigation to the nucleus via retrograde vesicular trafficking. Herein, we demonstrate that histone-targeting leads to ∼4-fold enhancements in osteogenic bone morphogenetic protein-2 (BMP-2) expression by MSCs over 6 days, as compared with standard polymeric transfection reagents. This improved expression augmented chondrogenesis, an essential first step in fracture healing. Importantly, significant enhancements of cartilage-specific protein expression were triggered by histone-targeted gene transfer, as compared with the response to treatment with equivalent amounts of recombinant BMP-2 protein. In fact, an ∼100-fold increase in recombinant BMP-2 was required to achieve similar levels of chondrogenic gene and protein expression. The enhancements in differentiation achieved using histone-targeting were in part enabled by an increase in transcription factor expression, which functioned to drive MSC chondrogenesis. These novel findings demonstrate the utility of histone-targeted gene transfer strategies to enable substantial reductions in BMP-2 dosing for bone regenerative applications.Statement of significanceThis contribution addresses significant limitations in non-viral gene transfer for bone regenerative applications by exploiting a novel histone-targeting approach for cell-triggered delivery that induces osteogenic BMP-2 expression coincident with the initiation of bone repair. During repair, proliferating MSCs respond to a complex series of growth factor signals that direct their differentiation along cellular lineages essential to mature bone formation. Although these MSCs are ideal targets for enhanced transfection during cellular mitosis, few non-viral delivery approaches exist to enable maximization of this effect. Accordingly, this contribution seeks to utilize our histone-targeted nanocarrier design strategy to stimulate BMP-2 gene transfer in dividing MSCs. This gene-based approach leads to significantly augmented MSC chondrogenesis, an essential first step in bone tissue repair.