Mechanisms of regulation of lymphocyte migration by actin cytoskeletal effectors

肌动蛋白细胞骨架效应器调节淋巴细胞迁移的机制

• 批准号: 10583309
• 负责人: Jordan Jacobelli
• 金额: $ 49.2万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-23 至 2027-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10583309
• 关键词: 3-Dimensional; Actins; Adhesions; Adhesives; Adopted; Autoimmune; Autoimmunity; Back; Biological Models; Blood Vessels; Cell Communication; Cell Nucleus; Cells; Characteristics; Collagen; Complement; Complex; Cues; Cytoskeletal Proteins; Cytoskeleton; DNA Sequence Alteration; Data; Disease; Embryonic Development; Endothelial Cells; Environment; Environmental Risk Factor; Extracellular Matrix; Extravasation; FMNL1 gene; Face; Family; Generations; Goals; Homologous Gene; Imaging Techniques; Immune; Immune response; Immune system; In Vitro; Inflammatory; Knowledge; Ligands; Location; Lymphocyte; Malignant Neoplasms; Mediating; Membrane; Methods; Microtubules; Modeling; Neoplasm Metastasis; Nonmuscle Myosin Type IIA; Pathologic; Physiological; Physiological Processes; Play; Protein Family; Proteins; Regulation; Role; Shapes; T-Lymphocyte; Testing; Therapeutic; Tissues; Traction Force Microscopy; Vascular Endothelium; Work; biophysical properties; cancer cell; cell motility; cell type; chemokine; constriction; immune function; immune system function; in vivo; insight; interstitial; lymph nodes; mechanical force; migration; novel; pathogen; three-dimensional modeling; trafficking; two photon microscopy; wound healing

Lymphocytes must correctly localize to mount effective immune responses. To do this, lymphocytes migrate through tissue environments with very different biophysical characteristics, including extravasation from blood vessels and crawling through cell-packed or extracellular matrix-rich tissues. To navigate through these diverse environments, lymphocytes squeeze through constrictions and migrate in low- or high-adhesive environments. However, there is a key gap in the understanding of how specific cytoskeletal effectors regulate force generation, shape changes, and cell-cell or cell-matrix interactions during lymphocyte migration in different settings. Given their relevance to immune function, primary T lymphocytes are a highly significant model to investigate cytoskeletal regulation of the varying modes of amoeboid cell motility in three-dimensional (3D) environments. Formin family proteins are cytoskeletal effectors involved in mediating actin network remodeling. Formin-like-1 (FMNL1) and Diaphanous-homologue-1 (mDia1) are the two most highly expressed Formins in T cells. We recently determined that FMNL1 is required for T cell transendothelial migration (TEM) and trafficking to inflamed tissues. Interestingly, our preliminary data support that FMNL1 and mDia1 have distinct functions in T cell migration through confined environments. Our goal is to achieve a more comprehensive understanding of the mechanisms by which the cytoskeleton enables migration through diverse tissue environments by determining the mode of action of Formin proteins in T cell motility. We will investigate the mechanisms by which Formins generate mechanical forces during T cell migration, the contribution of Formins in promoting T cell nucleus passage through constrictions, and how Formins regulate T cell motility in vivo. We will also determine if FMNL1 and mDia1 act independently or in concert with the Arp2/3 complex and/or Myosin-IIA. Our hypothesis is that to promote migration through complex environments FMNL1 mediates force generation from the back of the T cell while mDia1 creates force and membrane protrusions at the cell front. To test this hypothesis, we will use a multi-faceted approach, including genetic/mutational approaches and advanced imaging techniques in complementary model systems in vitro and physiological environments in vivo. Aim 1: Determine the mechanisms by which FMNL1 and mDia1 promote T cell transendothelial migration. Aim 2: Determine how FMNL1 and mDia1 regulate T cell motility within 3D environments with diverse biophysical characteristics. Aim 3: Define how Formins regulate T cell extravasation and interstitial motility in vivo. Overall, our studies are significant in that they will advance our knowledge of T cell migration by providing new data to determine the mechanism of action of Formins in T cell motility and if they cooperate with Myosin-IIA to promote migration through environments with varied biophysical characteristics. Thus, this work has the potential to provide important insight into novel ways to therapeutically modulate lymphocyte migration, such as in autoimmune settings and inflammatory diseases.

淋巴细胞必须正确定位才能产生有效的免疫反应。为此，淋巴细胞 迁移通过生物物理特性截然不同的组织环境，包括外渗 从血管中爬行，穿过充满细胞或富含细胞外基质的组织。导航通过 在这些不同的环境中，淋巴细胞挤压通过收缩并以低粘附或高粘附的方式迁移 环境。然而，在理解特定细胞骨架效应器如何调节方面存在关键差距 淋巴细胞迁移过程中力的产生、形状变化以及细胞-细胞或细胞-基质相互作用 不同的设置。鉴于其与免疫功能的相关性，原代 T 淋巴细胞是非常重要的 研究变形虫细胞三维运动不同模式的细胞骨架调节的模型 (3D) 环境。 Formin 家族蛋白是参与介导肌动蛋白网络的细胞骨架效应器 重塑。 Formin-like-1 (FMNL1) 和 Diaphanous-homologue-1 (mDia1) 是表达量最高的两种 T 细胞中的福尔明。我们最近确定 FMNL1 是 T 细胞跨内皮迁移 (TEM) 所必需的 并贩运至发炎组织。有趣的是，我们的初步数据支持 FMNL1 和 mDia1 T 细胞在有限环境中迁移的独特功能。我们的目标是实现更多 全面了解细胞骨架通过多种方式迁​​移的机制 通过确定 Formin 蛋白在 T 细胞运动中的作用模式来了解组织环境。我们将调查 Formins 在 T 细胞迁移过程中产生机械力的机制， 福明素促进 T 细胞核通过收缩，以及福明素如何调节 T 细胞运动 体内。我们还将确定 FMNL1 和 mDia1 是独立作用还是与 Arp2/3 复合体协同作用 和/或肌球蛋白-IIA。我们的假设是通过复杂环境促进迁移 FMNL1 介导 T 细胞背面产生力，而 mDia1 在 细胞前面。为了检验这个假设，我们将使用多方面的方法，包括遗传/突变 体外和生理学互补模型系统的方法和先进成像技术 体内环境。目标 1：确定 FMNL1 和 mDia1 促进 T 细胞的机制 跨内皮迁移。目标 2：确定 FMNL1 和 mDia1 如何在 3D 内调节 T 细胞运动 具有不同生物物理特征的环境。目标 3：定义福明斯如何调节 T 细胞外渗 和体内间质运动。总的来说，我们的研究意义重大，因为它们将增进我们对 T 的了解 通过提供新数据来确定福尔明在 T 细胞运动中的作用机制，以及如果 他们与肌球蛋白-IIA 合作，促进在不同生物物理环境中的迁移 特征。因此，这项工作有可能为新的治疗方法提供重要的见解。 调节淋巴细胞迁移，例如在自身免疫环境和炎症性疾病中。