Totani L, Cumashi A, Piccoli A, Lorenzet R
"Antonio Taticchi" Unit for Atherosclerosis and Thrombosis, Department of Vascular Medicine and Pharmacology, Istituto di Ricerche Farmacologiche Mario Negri, Consorzio Mario Negri Sud, Santa Maria Imbaro, Italy.
Arterioscler Thromb Vasc Biol. 1998 Oct;18(10):1534-40. doi: 10.1161/01.atv.18.10.1534.
Polymorphonuclear leukocytes (PMNs) and endothelial cells interact at sites of vascular injury during inflammatory response and during the development of atherosclerotic lesions. Such close proximity leads to the modulation of several of the biological functions of the 2 cell types. Because we have shown previously that PMNs enhance release of growth factors from resting endothelial cells, we decided to evaluate whether coincubation of PMNs with interleukin-1beta (IL-1beta)-stimulated human umbilical vein endothelial cells (HUVEC) could further modulate mitogen release from HUVEC. We found that PMN-HUVEC coincubation resulted in a 10-fold increase in mitogen release, compared with HUVEC alone (14+/-6 versus 1.3+/-0.1). When PMNs were incubated with IL-1beta-treated HUVEC, a further increase in mitogen release (up to 35-fold) was observed. The mitogenic activity was immunologically related to platelet-derived growth factor (PDGF) because the activity was abolished by an anti-PDGF antibody. PDGF-AB antigen, detected in low concentrations in conditioned medium from HUVEC alone, was increased 4-fold when IL-1beta or PMNs were incubated with HUVEC and dramatically upregulated (up to 40-fold) when PMNs were cocultured with IL-1beta-treated HUVEC. The presence of the protease inhibitor eglin C abolished mitogenic activity generation, suggesting a role for PMN-derived elastase and cathepsin G. Indeed, purified elastase and cathepsin G mimicked PMN-induced mitogen release from HUVEC. Because PMNs firmly adhered to IL-1beta-treated HUVEC, we investigated the role of cell-cell adhesion in mitogen release. Adhesion and PDGF release were inhibited by approximately 60% in the presence of anti-CD11a/CD18 and anti-intercellular adhesion molecule-1 monoclonal antibodies. This study suggests a new role for PMNs and their interaction with endothelium in pathological conditions in which intimal hyperplasia is a common feature.
在炎症反应以及动脉粥样硬化病变发展过程中，多形核白细胞（PMNs）与内皮细胞在血管损伤部位相互作用。如此紧密的接触导致这两种细胞类型的多种生物学功能受到调节。因为我们之前已经表明，PMNs可增强静息内皮细胞生长因子的释放，所以我们决定评估PMNs与白细胞介素-1β（IL-1β）刺激的人脐静脉内皮细胞（HUVEC）共同孵育是否能进一步调节HUVEC中促有丝分裂原的释放。我们发现，与单独的HUVEC相比，PMN-HUVEC共同孵育导致促有丝分裂原释放增加了10倍（分别为14±6和1.3±0.1）。当PMNs与经IL-1β处理的HUVEC孵育时，观察到促有丝分裂原释放进一步增加（高达35倍）。促有丝分裂活性在免疫学上与血小板衍生生长因子（PDGF）相关，因为该活性被抗PDGF抗体消除。单独的HUVEC条件培养基中以低浓度检测到的PDGF-AB抗原，在IL-1β或PMNs与HUVEC孵育时增加了4倍，而当PMNs与经IL-1β处理的HUVEC共培养时则显著上调（高达40倍）。蛋白酶抑制剂依林C的存在消除了促有丝分裂活性的产生，提示PMN衍生的弹性蛋白酶和组织蛋白酶G发挥了作用。实际上，纯化的弹性蛋白酶和组织蛋白酶G模拟了PMN诱导的HUVEC促有丝分裂原释放。由于PMNs牢固地黏附于经IL-1β处理的HUVEC，我们研究了细胞间黏附在促有丝分裂原释放中的作用。在存在抗CD11a/CD18和抗细胞间黏附分子-1单克隆抗体的情况下，黏附及PDGF释放受到约60%的抑制。这项研究提示了PMNs及其与内皮细胞的相互作用在以内膜增生为共同特征的病理状况中的新作用。
