Topp Stefan A, Upadhya Gundumi A, Strasberg Steven M
Department of Surgery, Washington University in St. Louis, St. Louis, MO, USA.
Liver Transpl. 2003 Dec;9(12):1286-94. doi: 10.1016/j.lts.2003.09.008.
Leukocyte adhesion on reperfusion is a critical component of cold preservation injury, and involves increased intercellular adhesion molecule 1 (ICAM-1) expression on sinusoidal endothelial cells (SEC). This study determined whether ICAM-1 expression occurs during cold preservation and whether actin disassembly is necessary for ICAM-1 expression and leukocyte adhesion. ICAM-1 expression was measured in isolated rat SEC during 8 hours of cold preservation by immunofluorescence techniques. Leukocyte adhesion to cold-preserved SEC was measured in an assay using fluorescently labeled leukocytes. The calpain inhibitors N-acetyl-leu-leu-norleucinal/N-acetyl-leu-leu-methioninal and the actin stabilizer phalloidin were added in some studies to prevent actin disassembly. Cold-exposed SEC showed a rapid increase of surface ICAM-1 expression, reaching maximum values in 1 hour. Studies in permeabilized cells suggested that ICAM-1 moved from a perinuclear location to the cell surface. Actin stabilization had no effect on the time-dependent increase in ICAM-1 expression, but seemed to affect the distribution of ICAM-1 on the cell surface. Leukocyte adhesion to SEC correlated with ICAM-1 expression and was reduced to control levels by an anti-ICAM-1 antibody. Although actin stabilization did not reduce ICAM-1 expression, it did reduce leukocyte-SEC adhesion to control values. Increased ICAM-1 expression on cold-preserved SEC is a direct effect of cold. It is not related to actin disassembly, although it seems that actin disassembly affects the distribution of ICAM-1. Leukocyte adhesion to cold-preserved SEC requires both increased ICAM-1 and actin disassembly. Agents that inhibit actin disassembly can significantly decrease leukocyte adhesion regardless of increased ICAM-1 expression.
再灌注时白细胞黏附是冷保存损伤的关键组成部分，且涉及肝血窦内皮细胞（SEC）上细胞间黏附分子1（ICAM-1）表达增加。本研究确定ICAM-1表达是否在冷保存期间发生，以及肌动蛋白解聚对于ICAM-1表达和白细胞黏附是否必要。通过免疫荧光技术在分离的大鼠SEC冷保存8小时期间测量ICAM-1表达。在一项使用荧光标记白细胞的试验中测量白细胞对冷保存SEC的黏附。在一些研究中加入钙蛋白酶抑制剂N-乙酰-亮氨酰-亮氨酰-正亮氨酸/N-乙酰-亮氨酰-亮氨酰-甲硫氨酸以及肌动蛋白稳定剂鬼笔环肽以防止肌动蛋白解聚。冷暴露的SEC显示表面ICAM-1表达迅速增加，在1小时内达到最大值。对通透细胞的研究表明ICAM-1从核周位置转移到细胞表面。肌动蛋白稳定对ICAM-1表达的时间依赖性增加没有影响，但似乎影响ICAM-1在细胞表面的分布。白细胞对SEC的黏附与ICAM-1表达相关，并通过抗ICAM-1抗体降低至对照水平。虽然肌动蛋白稳定并未降低ICAM-1表达，但确实将白细胞-SEC黏附降低至对照值。冷保存SEC上ICAM-1表达增加是寒冷的直接作用。它与肌动蛋白解聚无关，尽管似乎肌动蛋白解聚影响ICAM-1的分布。白细胞对冷保存SEC的黏附既需要ICAM-1增加，也需要肌动蛋白解聚。抑制肌动蛋白解聚的试剂可显著降低白细胞黏附，而与ICAM-1表达增加无关。
