Binns R M, Pabst R, Licence S T
Immunology Department, AFRC Institute of Animal Physiology, Cambridge, U.K.
Immunology. 1988 Feb;63(2):261-7.
The emigration of labelled thymus cells in the pig was studied directly in blood draining the large right distal cervical lobe of the thymus after controlled labelling with FITC delivered through cannulated branches of a main thymic artery and vein by temporary ex vivo perfusion at body temperature. Roughly 1% of thymic cells emigrated per day. Unlike most thymocytes, which are small, the size spectrum of thymic emigrants is slightly larger than that of typical blood lymphocytes. Surface-marker studies show that the surface phenotypes of the emigrants differ from both typical thymus and peripheral blood lymphocytes. Although the emigrants resemble thymocytes in the high proportion of strong rosettes formed with sheep red blood cells (RBC), they rosette poorly with pig red cells, particularly in the unenhanced saline test, in this respect behaving like blood lymphocytes. The peripheral T-cell subset bearing a Fc receptor is almost absent in thymus, but is well represented among the emigrants which thus resemble corticosteroid-resistant thymocytes in the pig. The large population of thymus-dependent Null lymphocytes in young pig blood apparently arise in thymus since they constitute 1/3 of emigrants, although only forming less than 10% of thymus cells. This emigration of thymic cells is discussed in relation to its implications for the turnover of known functional peripheral T-cell populations.
在用荧光素异硫氰酸酯（FITC）进行标记后，通过在体温下对猪胸腺主要动静脉的插管分支进行临时离体灌注，直接研究了猪体内标记胸腺细胞的迁移情况。标记后的胸腺细胞大约每天有1%迁移。与大多数体积较小的胸腺细胞不同，胸腺迁出细胞的大小范围比典型的血液淋巴细胞略大。表面标志物研究表明，迁出细胞的表面表型既不同于典型的胸腺细胞，也不同于外周血淋巴细胞。尽管迁出细胞与胸腺细胞相似，与绵羊红细胞（RBC）形成强玫瑰花结的比例较高，但它们与猪红细胞形成玫瑰花结的能力较差，尤其是在未增强的盐水试验中，在这方面表现得像血液淋巴细胞。胸腺中几乎不存在带有Fc受体的外周T细胞亚群，但在迁出细胞中该亚群数量较多，因此猪的迁出细胞类似于抗皮质类固醇的胸腺细胞。幼猪血液中大量依赖胸腺的裸淋巴细胞显然起源于胸腺，因为它们占迁出细胞的三分之一，尽管在胸腺细胞中所占比例不到10%。本文讨论了胸腺细胞的这种迁移及其对已知功能性外周T细胞群体更新的影响。
