Mechanism for a dendritic cell transport in the hepatic sinusoids and lymph.

本研究的目的：肝脏不断被抗原呈递树突状细胞（DC）的交通调查。我们研究了DC在肝脏微结构内的转运系统以及调节这种转运的因素。结果1。静脉转移大鼠DC易位并选择性地积聚在肝淋巴结旁皮层（已发表）。大鼠肝移植后不久，供体MHCII+细胞迁移到脾脏的T细胞区和B细胞区。肝淋巴渗漏到腹膜腔，淋巴中的DC被膈淋巴丛吸收，并转运到前纵隔淋巴结。推测供体MHCII+细胞与肝脏中的DC祖细胞相对应（在制备中）。结果2。将大量大鼠DC静脉注射到同种异体宿主体内，动态追踪DC在肝组织中的命运。我们发现DC首先被库普弗细胞捕获在正弦壁上，可能是通过机械和分子相互作用。被包裹的DC可能渗出到椎间盘间隙，然后离开肝小叶进入门静脉区域的组织间隙。最终这些细胞可能会爬进位于门静脉区的淋巴毛细血管（在第103届日本解剖学大会上提出）。这将由与庆应义塾大学的M.Suematsu博士（目前正在研究中）合作使用共聚焦激光显微摄影术进行体内观察。结果3。在正常大鼠的正弦区，经常观察到DC和Kupffer细胞之间的密切联系。肝窦中的大鼠Kupffer细胞能够选择性地捕获体内和体外血液中的DC（已发表），这表明存在某些粘附分子，可能是糖残基和leetins。通过这种方式，DC可能附着在正弦壁上，这可能是外渗的前奏。目前正在与T.Suganuma博士合作进行研究。宫崎医学院。

Aim of this study : Liver is constantly surveyed by a traffic of antigen-presenting dendritic cells (DC). We studied about the transport system of DC within the liver microarehitecture and factors which regulate this transport.Result 1. intravenously transferrd rat DC translocated and selectively accumulated in the paracortex of the hepatic lymph nodes (published). Soon after the rat liver transplantation, donor MHCII+ cells migrated to both T and B cell areas of thc spleen. The hepatic lymph leaked into the peritoncal cavity and DC in lymph were absorbed into diaphragmatic lymph plexus and transported to the anterior mediastinal LN.Donor MHCII+ cells arc speculated to correspond to DC progenitors in the liver (in preparation).Result 2. A large number of rat DC were injected intravenously to allogencic host and a fate of the DC in the liver tissue was traced lime kinetically. We found that DC were first entrapped by the Kupffer cells in the sinusoidal wall possibly through mechanical and molecular interactions. The entrapped DC may extravasate into the Disse's space and then exit the hepatic lobule into tissue space of the portal area. Eventually these cells probably crawl into the lymphatic capillary located in the portal area (presented at 103rd Japanese Anatomy Congress). This will be confinned by in vivo observation using confocal laser microlluorography by a collaboration with Dr. M.Suematsu, Keio University (now under study).Result 3. In the sinusoidal area a close association between the DC and Kupffer cells is often observed in normal rats. Rat Kupffer cells in the hepatie sinusoids are capable of selectively trapping DC from the blood in vivo and in vitro (published) suggesting a presence of certain adhesion molecules, possibly sugar residues and leetins. By this, DC could attach to the sinusoidal wail probably as a prelude to extravasation. This is now under study by collaborating with Dr. T.Suganuma. Miyazaki Medical College.