Development of an Inducible Conditional Gene Deletion Mouse Model to Study Plasma Cell Development and Longevity

开发可诱导条件基因缺失小鼠模型来研究浆细胞发育和寿命

• 批准号: 10452247
• 负责人: Peter Dion Pioli
• 金额: $ 5.4万
• 依托单位: UNIVERSITY OF SASKATCHEWAN
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-15 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10452247
• 关键词: Acute Myelocytic Leukemia; Adopted; Age; Aging; Animals; Antibodies; Antibody Formation; Antibody Repertoire; B cell differentiation; B-Lymphocytes; Behavior; Biological Models; Biological Process; Blood Cells; Bone Marrow; Cell Count; Cell surface; Cells; Cellular Assay; Cellularity; DNA Binding; DNA Damage; Deoxyuridine; Derivation procedure; Detection; Development; Disease; Dose; Elderly; Enterobacteria phage P1 Cre recombinase; Event; Female; Flow Cytometry; Fluorescence; Gene Deletion; Generations; Genes; Genetic Recombination; Glucose; Health; Hematopoietic; Hematopoietic stem cells; Human; Humoral Immunities; Immune response; Incidence; Individual; Inflammation; Inflammatory; Label; Lead; Link; Longevity; Maintenance; Mature B-Lymphocyte; Methods; Modeling; Mouse Protein; Mus; Myelogenous; Myeloid Leukemia; Myelopoiesis; Phenotype; Physiologic pulse; Physiological Processes; Plasma Cells; Plasmablast; Play; Population; Population Dynamics; Process; Production; Proteins; Protocols documentation; Reporter; Research; Role; Sex Bias; Sex Differences; Site; Spleen; System; T-Lymphocyte; Tamoxifen; Techniques; Technology; Terminator Codon; Testing; Thymus Gland; Time; Work; Youth; adaptive immune response; age related; aged; aging population; base; cell age; cell behavior; experimental study; glucose analog; glucose uptake; healthspan; male; mouse Cre recombinase; mouse model; plasma cell development; progenitor; prospective; response; sex; sex disparity; therapy development; transcription factor; vaccine response

Project Summary/Abstract Aging is associated with an overall decline in the adaptive immune response with a bulk of the research focusing on the deficiencies surrounding not only the function, but also the generation, of naive B and T lymphocytes. In contrast, not much is known about how aging alters the functionality of plasmacytes. Plasmacytes represent the terminal differentiation step of mature B cells and consist of both short-lived, proliferative plasmablasts (PBs) and more mature, non-proliferative plasma cells (PCs). These cells are key facilitators of humoral immunity through their robust production of antibodies (Abs) as well as their potential to be long-lived. In humans, this longevity can span decades. Historically, these cells have been considered nothing more than Ab factories; however, recent work has demonstrated the ability of plasmacytes to regulate a variety of physiological processes. In the context of aging, PCs have been shown to evolve a pro-inflammatory phenotype and be key drivers of the increased bone marrow (BM) myelopoiesis normally observed in the elderly. This is in part through the PC-dependent expansion in the numbers of hematopoietic stem cells and myeloid progenitors which has been linked to the elevated incidence of myeloid leukemias in the aged population. More recently, we have identified a sex disparity that exists in regard to PB/PC populations within the young thymus (THY) in which 3 months old female mice have significantly higher numbers of these cells compared to males. Interestingly enough, these THY PBs/PCs express key proteins required for THY T cell selection and their numbers significantly correlate with overall THY cellularity. Similar to BM, we have observed changes in THY PB/PC populations in the context of aging. In particular, male mice accumulate THY PBs/PCs with age while numbers remain constant in females. This is in contrast to BM and spleen (SPL) where PBs/PCs increase with age in both sexes. Thus, understanding how PBs/PCs age will allow us to better evaluate their role(s) in adaptive immune responses in the elderly as well as their evolving repertoire of Ab-independent functions. Ultimately, this may lead to the development of therapies that alter PB/PC behavior and promote increased healthspan in aged individuals. It is currently difficult to identify bona fide long-lived, or aged, plasmacytes. While a variety of cell surface markers have been shown to identify plasmacytes, these determinants do not necessarily correlate with longevity but rather maturity. Alternatively, cell labeling techniques rely on efficient labeling of upstream B cells and label retention in the subsequently generated PBs/PCs. In some instances, detection of these labels requires cell permeabilization thus eliminating the ability to further study living, aged PBs/PCs. Aim 1 focuses on the development of an inducible system to indelibly mark, or timestamp, plasmacytes using a fluorescence reporter thus facilitating the ability to assess population dynamics and potentially isolate cells of various ages. Aim 2 will demonstrate the feasibility of this reporter system to specifically determine differential population turnover and/or maintenance in female versus male THY plasmacytes.

项目概要/摘要 衰老与适应性免疫反应的整体下降有关，大部分研究集中在 不仅涉及幼稚 B 淋巴细胞和 T 淋巴细胞的功能缺陷，还涉及其生成缺陷。在 相比之下，人们对于衰老如何改变浆细胞的功能知之甚少。浆细胞代表 成熟 B 细胞的终末分化步骤，由短命、增殖性浆母细胞 (PB) 组成 以及更成熟的非增殖性浆细胞（PC）。这些细胞是体液免疫的关键促进者 通过它们强大的抗体 (Ab) 产生能力以及长寿的潜力。在人类中，这 寿命可以跨越数十年。从历史上看，这些细胞被认为只不过是抗体工厂。 然而，最近的研究表明浆细胞具有调节多种生理功能的能力。 流程。在衰老的背景下，PC 已被证明会进化出促炎表型，并且是关键 通常在老年人中观察到的骨髓（BM）骨髓生成增加的驱动因素。这部分是通过 造血干细胞和骨髓祖细胞数量的 PC 依赖性扩增 与老年人口中髓系白血病发病率升高有关。最近，我们有 确定了年轻胸腺 (THY) 内 PB/PC 群体存在的性别差异，其中 3 与雄性小鼠相比，几个月大的雌性小鼠中这些细胞的数量明显更高。有趣的是 足够了，这些 THY PB/PC 表达 THY T 细胞选择所需的关键蛋白质及其数量 与整体 THY 细胞结构显着相关。与 BM 类似，我们观察到 THY PB/PC 的变化 人口老龄化背景下。特别是，雄性小鼠随着年龄的增长而积累 THY PB/PC，而数量 在女性中保持不变。这与 BM 和脾 (SPL) 形成鲜明对比，其中 PB/PC 均随着年龄的增长而增加 性别。因此，了解 PB/PC 如何老化将使我们能够更好地评估它们在适应性免疫中的作用 老年人的反应以及他们不断发展的与抗体无关的功能。最终，这可能 导致改变 PB/PC 行为并促进老年人健康寿命的疗法的开发 个人。目前很难识别真正的长寿或老化的浆细胞。虽然各种细胞 表面标记已被证明可以识别浆细胞，这些决定因素不一定与 长寿，而是成熟。或者，细胞标记技术依赖于上游 B 细胞的有效标记 以及随后生成的 PB/PC 中的标签保留。在某些情况下，检测这些标签需要 细胞透化从而消除了进一步研究活的、老化的 PB/PC 的能力。目标 1 侧重于 开发诱导系统，使用荧光报告器对浆细胞进行不可磨灭的标记或时间戳 从而促进评估群体动态并可能分离不同年龄的细胞的能力。目标2将 证明该报告系统的可行性，以具体确定不同的人口流动和/或 女性与男性 THY 浆细胞的维持。