Department of Medical Cosmetology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
J Cell Physiol. 2020 Oct;235(10):6754-6766. doi: 10.1002/jcp.29569. Epub 2020 Feb 3.
Mesenchymal stem/stromal cells (MSCs) play an important role in bone tissue engineering because MSCs possess multilineage potential of differentiation to mesenchymal tissues. Semaphorin 3A (Sema3A) and hypoxia-inducible factor-1α (HIF1α) are proved as important regulatory factors for osteogenesis and angiogenesis. The aim of this study was to investigate the effects of Sema3A and HIF1α co-overexpression on the osteogenesis and angiogenesis in induced pluripotent stem cell-derived mesenchymal stem cells (iPSC-MSCs). Importantly, we assessed the potential osteogenic effectiveness of Sema3A and HIF1α co-overexpressed iPSC-MSCs seeded on hydroxyapatite (HA) scaffold in a mouse calvarial defect model. The overexpression for Sema3A, HIF1α, or Sema3A-HIF1α fusion in iPSC-MSCs was performed by separately infecting with conducted lentiviral vector. We determined the cell proliferation, the expressions of osteogenic, and endothelial markers of iPSC-MSCs cultured in osteogenic or endothelial induction medium in vitro. A mouse model calvarial defect was created and implanted with the Empty implant, HA scaffold alone, HA scaffold combined with iPSC-MSCs that infected with negative control or Sema3A-HIF1α fusion for 8 weeks in vivo. The results showed that Sema3A and HIF1α co-overexpression reversed the reduced cell proliferation that reduced by Sema3A overexpression alone. Importantly, the co-overexpression significantly increased the expressions of osteogenic and angiogenic related-genes compared with negative control after induction. Moreover, the Sema3A-HIF1α co-overexpressed iPSC-MSCs seeded on HA scaffold boosted the new bone and collagen fiber formation and facilitated repair of calvarial defect in a mouse model, which might have the potential application for bone defect reconstruction.
间充质干细胞（MSCs）在骨组织工程中起着重要作用，因为 MSCs 具有向间充质组织分化的多能性。信号素 3A（Sema3A）和缺氧诱导因子 1α（HIF1α）已被证明是成骨和血管生成的重要调节因子。本研究旨在探讨 Sema3A 和 HIF1α 共过表达对诱导多能干细胞衍生间充质干细胞（iPSC-MSCs）成骨和成血管的影响。重要的是，我们评估了在小鼠颅骨缺损模型中，接种在羟基磷灰石（HA）支架上的 Sema3A 和 HIF1α 共过表达 iPSC-MSCs 的潜在成骨效果。通过分别感染携带 Sema3A、HIF1α 或 Sema3A-HIF1α 融合基因的慢病毒载体，实现 iPSC-MSCs 的过表达。我们在体外培养条件下，检测了 iPSC-MSCs 在成骨或血管生成诱导培养基中的细胞增殖和骨生成、内皮标志物的表达。在体内，创建了小鼠颅骨缺损模型，并植入空植入物、HA 支架单独、HA 支架与感染阴性对照或 Sema3A-HIF1α 融合的 iPSC-MSCs 8 周。结果表明，Sema3A 和 HIF1α 共过表达逆转了单独过表达 Sema3A 引起的细胞增殖减少。重要的是，与阴性对照相比，诱导后共过表达显著增加了成骨和成血管相关基因的表达。此外，Sema3A-HIF1α 共过表达的 iPSC-MSCs 接种在 HA 支架上，促进了新骨和胶原纤维的形成，促进了小鼠颅骨缺损的修复，这可能为骨缺损重建提供了潜在的应用。
