MOLECULAR ANALYSIS OF MACROPHAGE ACTIVATION VIA LBP:LPS

CD14是一种强烈表达的单核细胞分化抗原 单核细胞表面，粒细胞表面弱阳性。CD14最近 被证明是一种由以下组成的复合体的受体 脂多糖和一种名为LBP的急性时相血清蛋白 (脂多糖结合蛋白)。LBP：LPS络合物与LBP的结合 单核细胞通过CD14导致巨噬细胞的强烈激活 通过产生肿瘤坏死因子(TNF)来衡量。激活 巨噬细胞通过这一途径被认为是 内毒素休克时肿瘤坏死因子的产生及其在血管内毒素休克中的作用 心血管-肺-肾系统。这个项目的主要目标是 建议确定可溶性形式的CD14是否可以抑制 通过LBP：LPS途径激活巨噬细胞并进一步定义 分子水平上巨噬细胞活化途径的作图 LBP：CD14分子上的LPs结合部位。此外，我们还将定义 可通过这种方式减少和/或抑制巨噬细胞活化的多肽 路径。可溶性CD14及其多肽将在体外进行分析 以及体内抑制内毒素诱导的巨噬细胞激活的能力 和/或死于内毒素休克。活体实验将 利用我们最近培育的转基因小鼠 表达人CD14，比正常更容易受到内毒素的影响 老鼠。这项提议的长期目标是使用CD14多肽来 减少和/或抑制革兰氏阴性感染性休克患者肿瘤坏死因子的产生 允许患者有时间对适当的 另类疗法。

CD14 is a myelomonocytic differentiation antigen expressed strongly on the surface of monocytes and weakly on granulocytes. CD14 has recently been shown to be a receptor for a complex consisting of lipopolysaccharide (LPS) and an acute phase serum protein called LBP (lipopolysaccharide binding protein). Binding of LBP:LPS complex to monocytes via CD14 results in strong activation of macrophages as measured by the production of tumor necrosis factor (TNF). Activation of macrophages by this pathway is thought to be the initial step in the production of TNF found in endotoxic shock and mediating the collapse of the cardiovascular-pulmonary-renal systems. The primary goals of this proposal are to determine whether soluble forms of CD14 can inhibit macrophage activation via the LBP:LPS pathway and to further define this pathway of macrophage activation at the molecular level by mapping the LBP:LPS binding site on the CD14 molecule. In addition, we will define peptides which can reduce and/or inhibit macrophage activation via this pathway. Soluble CD14 and its peptides will be analyzed both in vitro and in vivo for the ability to inhibit LPS-induced macrophage activation and/or death due to endotoxin shock. The in vivo experiments will utilize a transgenic mouse which we have recently produced which expresses human CD14 and which is more susceptible to LPS than normal mice. The long term goal of this proposal is to use CD14 peptides to reduce and/or inhibit TNF production in gram negative septic shock with the prospect of allowing time for the patient to respond to appropriate alternative therapy.