Abstract

Growth hormone (GH), in addition to its classic actions on growth and metabolism in the body, exerts pleiotropic effects on the immune system, particularly on the thymus. The aim of this study was to evaluate the influence of GH on the interactions between mature thymocytes and the thymic endothelium involved in the migratory process. To this end, fresh thymocytes (C57BL/6 mice) and the thymic endothelial cell line (tEnd.1) were used. In the cell adhesion assay, the GH-treated thymocytes adhered more to tEnd.1 cells. Additionally, there was an improvement in the deposition of fibronectin by tEnd.1 cells when co-cultured with GH-pre-treated thymocytes. Furthermore, GH induced thymocyte F-actin polymerization. In the transendothelial migration assay, a large number of GH-treated thymocytes, mainly the CD4⁻CD8⁺ subset, migrated towards the endothelium under the stimulus of insulin-like growth factor 1. In conclusion, we demonstrated the positive actions of GH in thymocyte/thymic endothelium interactions, including transendothelial migration.

摘要

生长激素 (GH) 除了对体内生长和新陈代谢的经典作用外，还对免疫系统，特别是对胸腺发挥多效作用。本研究的目的是评估 GH 对成熟胸腺细胞和参与迁移过程的胸腺内皮细胞之间相互作用的影响。为此，使用了新鲜的胸腺细胞（C57BL/6 小鼠）和胸腺内皮细胞系（tEnd.1）。在细胞粘附试验中，经 GH 处理的胸腺细胞更多地粘附于 tEnd.1 细胞。此外，当与 GH 预处理的胸腺细胞共培养时，tEnd.1 细胞的纤连蛋白沉积有所改善。此外，GH 诱导胸腺细胞 F-肌动蛋白聚合。在跨内皮迁移试验中，大量 GH 处理的胸腺细胞，主要是 CD4 ^- CD8⁺子集，在胰岛素样生长因子 1 的刺激下向内皮迁移。 总之，我们证明了 GH 在胸腺细胞/胸腺内皮相互作用中的积极作用，包括跨内皮迁移。