MECHANISM OF HUMAN TRANSENDOTHELIAL LEUKOCYTE MIGRATION

以白细胞移出为特征的炎症反应 血管对液体和蛋白质的渗透性增加 在包括感染在内的许多常见疾病状态中， 动脉粥样硬化、急性呼吸窘迫综合征和免疫 复杂的疾病。 检查白细胞迁移， 内皮细胞（EC）渗透性的改变 屏障，我已经培养了人类EC单层的基板上， 人类羊膜 我测量了这些物质的渗透性 细胞单层和EC胞浆游离钙（（Ca++）i）的变化 在人中性粒细胞（PMN）迁移穿过这种EC期间， 单层。 中性粒细胞的跨上皮迁移是 对化学引诱剂，并不改变EC的渗透性 单层。 组胺，增加EC单层 渗透性和PMN穿过EC单层的迁移诱导 EC（Ca++）i增加，EC形状改变。 的目标 建议的研究是：1）确定是否PMN表面 蛋白质和/或分泌产物引发EC（Ca++）i变化 使用抗白细胞表面蛋白的抗体， 来源于活化的PMN的上清液，2）检查作用 EC（Ca++）i变化介导的跨内皮PMN 迁移或渗透性变化，通过检查 缓冲EC（Ca++）i随这些事件的变化; 3）寻找EC 肌球蛋白轻链磷酸化或肌动蛋白重排 刺激EC作为迁移白细胞和激动剂 例如组胺诱导EC细胞骨架变化， 改变EC单层渗透性，和4）检查 （Ca++）i与血管通透性变化的关系 内皮细胞和上皮细胞单层， 增加EC单细胞膜的通透性，影响EC（Ca++）i 如果中性粒细胞穿过单层上皮细胞的迁移改变了 上皮细胞（Ca++）i.

An inflammatory response characterized by leukocyte emigration and increased vascular permeability to fluids and proteins is seen in a number of common disease states including infection, atherosclerosis, acute respiratory distress syndrome, and immune complex diseases. To examine leukocyte migration and alterations in permeability across an endothelial cells (EC) barrier, I have cultured human EC monolayers on a substrate of human amnion. I have measured the permeability of these monolayers and changes in EC cytosolic free calcium ((Ca++)i) during human neutrophil (PMN) migration across such EC monolayers. Transendothelial PMN migration occurs in response to chemoattractants and does not alter the permeability of EC monolayers. Both histamine, which increases EC monolayer permeability, and PMN migration across an EC monolayer induce increases in EC (Ca++)i and changes in EC shape. The goals of the proposed research are: 1) to determine whether PMN surface proteins and/or secretory products initiate EC (Ca++)i changes using antibodies against leukocyte surface proteins and supernatants derived from activated PMN, 2) to examine the role of EC (Ca++)i changes in mediating transendothelial PMN migration or permeability changes by examining the effect of buffering EC (Ca++)i changes on these events, 3) to search for EC myosin light chain phosphorylation or actin rearrangement in stimulated EC as evidence that migrating leukocytes and agonists such as histamine induce EC cytoskeletal changes as a basis for altering EC monolayer permeability, and 4) to examine the relationship between (Ca++)i and changes in the permeability of endothelial and epithelial monolayers by determining if substances which increase the permeability EC monolayers affect EC (Ca++)i and if PMN migration across monolayers of epithelial cells alter epithelial (Ca++)i.