Hiramine C, Hojo K, Matsumoto H
Department of Pathology, Kagawa Medical School, Kagawa, Japan.
Thymus. 1988;11(4):243-52.
Cyclosporin A (CsA) administration to normal, unprimed BALB/c mice at the dose of 20 mg/kg every other day for 3 weeks markedly reduced the thymus weight as well as the size and cellularity of the thymic medulla with relative preservation of the cortex. Area of the medullary compartment (the ratio of the area of medulla to area of cortex) of the CsA-treated mice decreased to about one half of that of the solvent alone-treated mice. Through the use of monoclonal anti-L3T4 and anti-Lyt-2 antibodies together with two-color flow cytofluorometry, we demonstrated that CsA caused a remarkable reduction of L3T4+ Lyt-2- subset and only a slight increase in L3T4+ Lyt-2+ subset in the thymus. There was no significant difference in the percentage of L3T4- Lyt-2+ subset between the CsA-treated and solvent-treated groups. Additionally, thymocytes from CsA-treated mice showed a marked reduction of in vitro proliferative responses to concanavalin A and phytohemagglutinin. The above mentioned results imply that in normal, unprimed mice CsA may preferentially impair L3T4+ Lyt-2- subset (helper T cells and their precursors) residing in the thymic medulla whereas is much less effective against L3T4+ Lyt-2+ subset present in the cortex and L3T4- Lyt-2+ subset.
每隔一天以20毫克/千克的剂量给正常、未致敏的BALB/c小鼠施用环孢菌素A（CsA），持续3周，可显著降低胸腺重量以及胸腺髓质的大小和细胞数量，而皮质相对保持完整。CsA处理组小鼠的髓质区面积（髓质面积与皮质面积之比）降至仅用溶剂处理组小鼠的约二分之一。通过使用单克隆抗L3T4和抗Lyt-2抗体以及双色流式细胞荧光术，我们证明CsA导致胸腺中L3T4 + Lyt-2 -亚群显著减少，而L3T4 + Lyt-2 +亚群仅略有增加。CsA处理组和溶剂处理组之间L3T4 - Lyt-2 +亚群的百分比没有显著差异。此外，来自CsA处理组小鼠的胸腺细胞对刀豆球蛋白A和植物血凝素的体外增殖反应显著降低。上述结果表明，在正常、未致敏的小鼠中，CsA可能优先损害位于胸腺髓质中的L3T4 + Lyt-2 -亚群（辅助性T细胞及其前体），而对皮质中存在的L3T4 + Lyt-2 +亚群和L3T4 - Lyt-2 +亚群的作用则小得多。
