Role of OC-STAMP expressed on human osteoclasts in periodontitis

本申请表为“认可Deia导师资格的行政补充(非-OD-23- 002)“给正在进行的R01赠款项目(DE029709)，题为”OC的作用--人类印章 ，建议建立人源化的牙周炎小鼠模型，以研究 人破骨细胞表达的OC-STAMP在牙周炎病变中的可能致病作用这个 NSG-SGM3-W41小鼠品系是目前研制的最先进的免疫缺陷小鼠品系之一 由杰克逊实验室的舒尔茨博士提出的，允许我们重建包含这两个 人造血干细胞移植后的髓系和淋巴系细胞 不受辐射限制的。最近使用人源化NSG小鼠的研究表明，人类OCS 在NSG小鼠的代理体中可以检测到来源于hHSCs的单核细胞系细胞。相关 对R01资助项目，我们初步发现，牙龈假单胞菌(P.gigivalis，PG)是牙周炎的关键病原菌。 牙周炎，增加人OC前体细胞OC-STAMP的表达。因为小鼠淋巴细胞 不要对口服PG产生致病免疫反应，有观点认为，人的淋巴细胞 在小鼠MHC-II的控制下，人源化小鼠可能不会产生足够数量的RANKL来 在人源化免疫缺陷小鼠中引起牙周炎。然而，我们发现，牙周骨丢失和 RAG1免疫缺陷小鼠可以通过结扎诱导局部产生RANKL，这表明 在结扎性小鼠牙周炎中，淋巴细胞不是RANKL的主要细胞来源。 此外，由于OC-STAMP由OCS和OC前体明显表达，而不是其他 来源于hHSCs的淋巴细胞，抗OC-STAMP抗体接种于人源化小鼠有望 仅对人类组织采取行动。我们假设PG依赖于通过以下方式上调OC-STAMP表达式 人OCS可促进人源化小鼠的病理性骨吸收 牙周炎。这一假说将通过以下两个目的来检验：1)检测抗OCST抗体的效果 人源化小鼠接种和不接种PG后牙周炎的发生和发展 目的：确定促进RANKL诱导的人OCS中OC-STAMP的配体。 在这项拟议的研究成功完成后，预计人类OC-STAMP的作用 人OCS在牙周炎中的表达将被测定。这种人性化的牙周炎小鼠模型 将为理解人类OCS上表达的分子的生理背景提供一个平台。

This application for “Administrative Supplements to Recognize Excellence in DEIA mentorship (NOT-OD-23- 002)” to the active R01 grant project (DE029709), entitled, “Role of OC-STAMP expressed on human osteoclasts in periodontitis”, proposes to develop a humanized mouse model of periodontitis to study the possible pathogenic roles of OC-STAMP expressed on human osteoclasts (OCs) in periodontitis lesion. The NSG-SGM3-W41 mouse strain which is one of the most advanced immunodeficient mouse strains developed by Dr. Shultz at the Jackson Laboratory allows us to reconstruct the full immune compartments containing both myeloid and lymphoid cell populations following transplantation of human hematopoietic stem cells (hHSC) without conditioning by irradiation. Recent study using humanized NSG mice showed that human OCs which are monocyte linage cells derived from hHSCs can be detected in the surrogate body of NSG mice. Relevant to parent R01 grant project, we preliminary discovered that, P. gingivalis (Pg), the keystone pathogen of periodontitis, increases the expression of OC-STAMP by human OC precursor cells. Since mouse lymphocytes don’t mount pathogenic immune response to orally inoculated Pg, it is argued that human lymphocytes which are under the control of mouse MHC-II in the humanized mice may not produce sufficient amount of RANKL to cause periodontitis in the humanized immunodeficient mice. However, we found that periodontal bone loss and local production of RANKL can be induced by ligature attachment to RAG1 immunodeficient mice, indicating that lymphocytes are not the major cellular source of RANKL in ligature-induced mouse periodontitis. Furthermore, because OC-STAMP is distinctively expressed by OCs and OC precursors, but not other lymphocytes derived from hHSCs, the anti-OC-STAMP Ab administered to humanized mice are expected to act on only human OCs. We hypothesize that Pg-dependently upregulated OC-STAMP expression by human OCs may promote the pathogenic bone resorption in the humanized mice indicative of periodontitis. This hypothesis will be tested by following two aims: 1) To examine the effects of anti-OCST Ab on the onset and progression of periodontitis induced in humanized mice with or without Pg inoculation, and 2) to determine the ligand of human OC-STAMP that promote the RANKL-induced OC-genesis in human OCs. Upon successful completion of this proposed study, it is anticipated that the roles of human OC-STAMP expressed by human OCs in periodontitis will be determined. This humanized mouse model of periodontitis would provide a platform for understanding the physiological context of molecules expressed on human OCS.