C1Q-INDUCED CA2+RESPONSES IN FIBROBLAST HETEROGENEITY

人牙龈成纤维细胞(HGF)在健康和健康中的不同功能 疾病。我们的目标是了解细胞和分子机制。 在伤口愈合过程中控制成纤维细胞的增殖。为此目的， 我们建立了一种体外模型，包括分离的、稳定的、 正常和正常HGF亚型的表型和代谢特征 具有独特炎性补体受体的肉芽组织 C1q.C1q由两个重要区域组成：胶原样结构域和 一个球状的区域。HGF可分为健康人cC1qR亚型 主要表达C1q胶原样结构域的受体，以及 肉芽组织主要表达C1q受体的gC1qR亚型 球状域。在体内，C1q选择性地聚集在损伤部位。 在体外，C1q对HGF的增殖有60%到80%的抑制作用，提示 该蛋白作为生长因子调节因子的重要作用 活动。仅C1q可抑制gC1qR细胞的生长反应 在细胞周期的G1期；相比之下，C1q抑制 CC1qR细胞的生长不依赖于细胞周期。子类型的不同在于 C1q暴露后细胞内钙离子浓度的变化。我们 假设细胞内钙离子反应的差异导致 通过C1q的球状结构域与胶原样结构域结合到特定的 成纤维细胞受体是不同生长因子反应的基础 子类型，并且这种机制可能在 口腔组织细胞群与代谢活性的变化 在康复过程中。以下目标验证细胞内信号如何 C1q激活可能调节细胞的生长因子反应 正常组织和肉芽组织。对于C1q激活的每个亚型，AIM I量化第二信使cAMP和肌醇磷酸水平 动员和调节来自外部和外部的钙离子流动的周转 内部来源，并评估蛋白激酶A和C的激活。 II决定了这些第二信使在抑制中的作用 C1q对细胞生长的影响及对PDGF受体的调节 C1q的表达和功能。目的刻画其动力学特征。 C1q诱导静息和生长因子钙离子内流/外流 激活的亚型，决定着特定的钙通道的激活 亚型的膜和激活细胞内特定的钙储存库。 结果将阐明成纤维细胞相互作用的意义 损伤部位补体C1q亚型及其相互关系 在伤口愈合过程中相互影响，这可能部分解释了 健康牙周组织和患病牙周组织的细胞群。这些研究 可能会导致一种新的方法或使用生长疗法的辅助疗法 促进组织再生的因素，通过设计方法提高- 或在选择的子类型中下调那些增长因素- 受C1q活性影响的因子信号级联 出现在治疗地点。

Human gingival fibroblast (HGF) function differently in health and disease. Our goal is to understand the cellular and molecular mechanisms that control fibroblast proliferation in wound healing. For this purpose we have established an in vitro model consisting of isolated, stable, phenotypically and metabolically characterized HGF subtypes of normal and granulation tissues with unique receptors for inflammatory complement C1q. C1q consists of two important regions: a collagen-like domain and a globular domain. HGF may be divided into subtype cC1qR of healthy gingiva expressing mainly receptors for C1q collagen-like domain, and subtype gC1qR of granulation tissue expressing mainly receptors for C1q globular domain. In vivo C1q selectively accumulates at sites of injury. In vitro C1q inhibits 60 to 80 % proliferation of HGF, suggesting an important role for this protein as a regulator of growth factors activities. The growth response of gC1qR cells is inhibited by C1q only during the G1 phase of the cell cycle; in contrast C1q inhibition of growth of cC1qR cells is cell cycle-independent. Subtypes differ in the pattern of cytosolic Ca2+ concentration following exposure to C1q. We hypothesize that the differences in intracellular Ca2+ response induced by the binding of globular versus collagen-like domain of C1q to specific fibroblast receptors underlie the different growth-factor response of subtypes, and that this mechanism may be important in the shifts of cellular populations and changes of metabolic activities of oral tissues during healing. The following aims verify how intracellular signals activated by C1q may regulate the growth-factor response of cells of normal and granulation tissues. For each subtype activated by C1q, Aim I quantifies levels of second messengers cAMP and inositol-phosphate turnover that mobilize and regulate Ca2+ flux from both external and internal sources, and assesses activation of protein kinases A and C. Aim II determines the role of these second messengers in the inhibitory effects of C1q on cell growth, and the regulation of PDGF receptor expression and function by C1q. Aim Ill characterizes the kinetics of C1q-induced Ca2+ influx/efflux in both resting and growth factor activated subtypes, determines activation of specific Ca2+channels on membrane of subtypes and activation of specific intracellular Ca2+stores. Results will elucidate significance of interactions of fibroblast subtypes with complement c1q at injured sites, relationship of subtypes to one another in wound healing, and may in part explain the shifts in cellular populations of healthy and diseased periodontium. These studies may lead to a new approach or adjunct to therapies that use growth factors to enhance tissue regeneration, by designing methodology that up- or down-regulates in the subtype of choice those elements of growth- factor signaling cascade that are affected by the activities of C1q present at sites of treatment.