MINE-MS for horizontal bone loss treatment

项目摘要 牙周炎是美国成年人中高度流行的口腔疾病，并且是导致牙齿丧失的主要原因。 恒牙据最近估计，42%的美国30岁以上的成年人患有牙周炎， 重度牙周炎占7.8%。破坏性牙周炎的特点是牙齿失去支持 包括牙槽骨在内的组织。临床上，牙槽骨丢失可以大致分为垂直（骨内）和 水平（骨上）骨丢失。令人惊讶的是，牙周炎的水平骨丢失是最常见的问题 面对临床医生，但很少受到关注。目前，没有产品提供满意的 水平牙槽骨丢失的治疗结果。因此，开发具有临床意义的 水平牙槽骨再生的创新生物材料和技术。在初步研究中， 多功能可注射纳米纤维ECM模拟微球（MINE-MS）系统具有几个独特的 设计并制造了这些特征。这些特点包括高机械强度、优异的可注射性 和细胞相容性，固化时间快，抗菌活性强，骨诱导性高。此外，短 肽E7对骨髓间充质干细胞（BMSC）具有高特异性亲和力， 鉴定了上皮和牙龈成纤维细胞。当E7肽与MINE-MS缀合时， 表面上，MINE-MS作为一个很好的生物屏障，通过显着增加细胞的数量来选择性地重新填充细胞。 在体外和体内均能增加骨髓间充质干细胞和排出上皮细胞和成纤维细胞。此外，飞行员 实验表明，MINE-MS成功地提高了牙槽嵴， 釉质基质衍生物（牙周炎治疗的临床产品）在小鼠牙周炎诱导的 水平骨丢失模型。这些令人兴奋的发现使MINE-MS成为治疗的绝佳候选者 水平牙槽骨的丢失。因此，拟议的项目是开发和优化 MINE-MS系统用于水平牙槽骨再生。在这项工作中提出了三个具体目标。目的 一是合成了MINE-MS，并对其性能进行了优化，包括可注射性、凝固时间、力学性能等 强度、细胞相容性和抗菌活性。目的2着重于将BMSC亲和肽 在MINE-MS表面上，评估和优化其作为选择性细胞生物屏障的功能 使用体外竞争性细胞粘附测定和牙周开窗缺损大鼠模型进行再增殖。在 目的3，将负载成骨肽的纳米球并入MINE-MS的核心中， 将检查增强骨再生的功能。最后，将对优化的MINE-MS进行测试， 大鼠牙周炎性水平骨丢失模型的牙周牙槽骨再生。成功 该项目的完成将解决牙周炎引起的水平牙槽骨损失的挑战， 为临床牙周牙槽骨再生迈出了重要的一步。

Project Summary Periodontitis is a highly prevalent oral disease among US adults and is the primary cause of the loss of permanent teeth. It was recently estimated that 42% of US adults aged 30 years or older have periodontitis, with 7.8% having severe periodontitis. Destructive periodontitis is characterized by the loss of dental supporting tissues including alveolar bone. Clinically, alveolar bone loss can be broadly divided into vertical (intrabony) and horizontal (suprabony) bone loss. Surprisingly, horizontal bone loss in periodontitis is the most common problem confronting clinicians but has received scant attention. Currently, there are no products offering satisfactory outcomes for the treatment of horizontal alveolar bone loss. Therefore, it is clinical significance to develop innovative biomaterials and technology for horizontal alveolar bone regeneration. In the preliminary studies, a multifunctional injectable nanofibrous ECM-mimicking microsphere (MINE-MS) system with several unique features was designed and fabricated. These features include high mechanical strength, excellent injectability and cytocompatibility, fast setting time, strong antibacterial activity, and high osteoinductivity. In addition, a short peptide E7 that has high specific affinity to bone marrow derived mesenchymal stem cells (BMSCs) and repels epithelial and gingival fibroblast cells was identified. When the E7 peptide was conjugated to the MINE-MS surface, the MINE-MS served as an excellent biological barrier to selectively repopulate cells by significantly increasing BMSCs and expelling epithelia and fibroblasts both in vitro and in vivo. Furthermore, the pilot experiment shows that the MINE-MS successfully elevated the alveolar crest and regenerated more bone than enamel matrix derivative (a clinical product for periodontitis treatment) in a mouse periodontitis-induced horizontal bone loss model. These exciting findings make the MINE-MS an excellent candidate for the treatment of horizontal alveolar bone loss in periodontitis. The proposed project, therefore, is to develop and optimize the MINE-MS system for horizontal alveolar bone regeneration. Three specific aims are proposed in this work. Aim 1 is to synthesize the MINE-MS and optimize the properties, including the injectability, setting time, mechanical strength, cytocompatibility, and antibacterial activity. Aim 2 focuses on incorporating the BMSC affinity peptide onto the MINE-MS surface, evaluating and optimizing its function as a biological barrier for selective cell repopulation using a competitive cell adhesion assay in vitro and a periodontal fenestration defect rat model. In Aim 3, an osteogenic peptide-loaded nanospheres will be incorporated into the core of the MINE-MS and its function for enhanced bone regeneration will be examined. Lastly, the optimized MINE-MS will be tested for periodontal alveolar bone regeneration in a rat periodontitis-induced horizontal bone loss model. Successful completion of this project will address the challenge of periodontitis-induced horizontal alveolar bone loss, making a significant step towards periodontal alveolar bone regeneration in clinic.