Aire-dependent regulation of spontaneous autoimmune-mediated alopecia

自发性自身免疫介导的脱发的空气依赖性调节

基本信息

批准号：
10464297
负责人：
Natella Maglakelidze
金额：
$ 2.68万
依托单位：
PENNSYLVANIA STATE UNIV HERSHEY MED CTR
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-04-01 至 2022-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10464297
关键词：
Address Adult Affect Alopecia Alopecia Areata Antigens Autoantigens Autoimmune Autoimmune Diseases Binding Biopsy C57BL/6 Mouse CD8B1 gene Cells Child Clinical Coculture Techniques Complex Cytotoxic T-Lymphocytes Data Dermatology Development Down-Regulation Epidermis Etiology Exhibits FDA approved Female Foundations General Population Genetic Transcription Goals Hair Hair follicle structure Harvest Histopathology Human Immune Individual Interferon Type II Janus kinase Lead Lesion Major Histocompatibility Complex Mediating Mentors Molecular Monitor Mus Pathogenesis Patients Physicians Play Prevalence Process Recurrence Regulation Research Research Training Risk Role STAT protein STAT1 gene Scalp structure Scientist Signal Pathway Single Nucleotide Polymorphism Skin Solid T-Lymphocyte Tamoxifen Testing Thymic epithelial cell Thymus Gland Tissues Transcriptional Regulation Up-Regulation Woman autoreactive T cell career chemokine clinical efficacy cytokine cytotoxic defined contribution experimental study improved inflammatory milieu inhibitor inhibitor therapy innovation insight keratinocyte kinase inhibitor lifetime risk loss of function mutation men monocyte mouse model novel off-label use skin disorder skin lesion subcutaneous

项目摘要

ABSTRACT This proposal will enable the applicant to acquire mentored research training and develop into a productive, independent physician-scientist in the field of dermatology. Alopecia areata (AA) is an autoimmune skin disease, characterized by patchy non-scarring hair loss, with no cure. AA is caused by inappropriate activation of autoreactive T cells that target and damage keratinocytes of anagen hair follicles (HFs) due to the collapse of HF immune privilege (IP). Why anagen HFs undergo IP collapse is not well-understood. Recently, Janus kinase inhibitors (JAKi) have shown clinical efficacy in AA patients by suppressing immune-cell activity at the HF, however, JAKi do not work for all AA patients. A better mechanistic understanding of JAK-STAT regulation can lead to more effective AA treatments. Our preliminary data indicates that we have a novel AA-like mouse model that exhibits spontaneous alopecia in mice genetically null for autoimmune regulator (Aire-/-). Aire is a transcriptional regulator expressed in medullary thymic epithelial cells that eliminates autoreactive T cells. We and others have recently shown that Aire is also expressed in epidermal and follicular keratinocytes. Increasing clinical evidence also supports the importance of Aire in AA, as patients with loss-of-function mutations in AIRE have an increased risk of developing AA. We observe adult female C57BL/6 Aire-/- (germline) mice spontaneously develop AA-like lesions (n=35/73). Skin biopsies from alopecic Aire-/- mice resemble human AA lesions on macroscopic, histopathologic, and molecular levels. Additionally, we observed upregulation in JAK-STAT signaling in Aire-/- skin lesions and AIRE-deficient cultured keratinocytes alongside downregulated expression of PIAS1, a STAT1 inhibitor. These findings suggest that 1) Aire is a critical regulator of HF IP in AA and 2) AIRE is a key suppressor of JAK-STAT signaling in keratinocytes. This proposal will address current gaps in our understanding of HF IP and JAK-STAT signaling in AA. In Aim 1, we hypothesize that the loss of either thymic or keratinocyte Aire contribute to HF IP collapse. To test this, we will harvest CD8+NKG2D+ T cells from alopecic Aire-/- mice, subcutaneously inject them into Aire+/+ mice and monitor them for AA onset. Cytolytic T cell activity will be assessed via keratinocyte co-culture experiments. The results of these studies will reveal whether thymic Aire loss is sufficient to trigger HF IP collapse. In parallel, we will test whether skin-specific deletion of Aire is sufficient to trigger HF IP collapse by utilizing tamoxifen-treated Airefl/flK5-CreERT2 mice. In Aim 2, we hypothesize that AIRE contributes to the regulation of IFNγ-JAK-STAT signaling in cultured keratinocytes. To test this, we will determine how AIRE influences the PIAS1, STAT1, and the PIAS1-STAT1 complex, assess which AIRE domains are required for JAK-STAT signaling, and identify the AA cytokines and chemokines expressed by AIRE-/- keratinocytes upon IFNγ stimulation. The results of these studies will uncover novel regulatory mechanisms of JAK-STAT signaling in AA.

抽象的该建议将使申请人能够获得心理研究培训，并发展成富有成效的，皮肤病学领域的独立身体科学家。脱发Areata（AA）是一种自身免疫性皮肤疾病，其特征是斑驳的无囊脱发，没有治愈。 AA是由靶向和损害角质形成细胞的自动反应性T细胞不当激活引起的由于HF免疫特权（IP）崩溃，Anagen毛发（HFS）。为什么Anagen HFS经历IP崩溃不是很好理解。最近，Janus激酶抑制剂（JAKI）显示了AA患者的临床效率但是，抑制HF的免疫细胞活性，Jaki并不适合所有AA患者。更好的机械对JAK-STAT调节的了解可以导致更有效的AA治疗。我们的初步数据指示我们有一种新型的AA样小鼠模型，该模型在小鼠中表现出赞成性脱发，通常为null 自动免疫调节器（AIRE - / - ）。 AIRE是在髓质胸腺上皮细胞中表达的转录调节剂这消除了自动反应性T细胞。我们和其他人最近表明，AIRE在表皮中也表达和卵泡角质形成细胞。越来越多的临床证据也支持AIR在AA中的重要性，因为患者随着AIR的功能丧失突变，患有AA的风险增加。我们观察到成年女性 C57BL/6 AIRE - / - （种系）小鼠赞助开发类似AA的病变（n = 35/73）。皮肤活检来自脱胶 AIRE - / - 小鼠在宏观，组织病理学和分子水平上类似于人类AA病变。另外，我们在AIRE - / - 皮肤病变和AIRE缺乏培养的角质形成细胞中观察到的JAK-STAT信号传导上调与STAT1抑制剂PIAS1的下调表达下调。这些发现表明1）AIRE是 AA和2）AIRE中HF IP的关键调节剂是角质形成细胞中JAK-STAT信号传导的关键抑制剂。该提案将解决我们对AA中HF IP和JAK-STAT信号的理解中的当前差距。在AIM 1中，我们假设胸腺或角质细胞AIRE的损失导致HF IP塌陷。为了测试这一点，我们将从脱发AIRE - / - 小鼠中收集CD8+ NKG2D+ T细胞，皮下注入AIRE+/+小鼠，并将其注入监视它们的AA发作。细胞溶解细胞活性将通过角质形成细胞共培养实验评估。这这些研究的结果将揭示胸腺AIRE损失是否足以触发HF IP崩溃。并行，我们将测试AIRE的皮肤特异性删除是否足以通过使用他莫昔芬治疗来触发HF IP崩溃 AIREFL/FLK5-CREERT2小鼠。在AIM 2中，我们假设AIRE有助于对IFNγ-JAK-STAT的调节培养的角质形成细胞中的信号传导。为了测试这一点，我们将确定AIRE如何影响PIAS1，STAT1和 PIAS1-STAT1复合物，评估JAK-STAT信号需要哪些AIRE域，并确定 IRE-/ - 角质形成细胞在IFNγ刺激时表达的AA细胞因子和趋化因子和趋化因子。这些结果研究将发现AA中JAK-STAT信号传导的新型调节机制。