von Boehmer Harald, Kisielow Pawel
Harvard Medical School, Dana-Farber Cancer Institute, Boston, MA 02115, USA.
Immunol Rev. 2006 Feb;209:284-9. doi: 10.1111/j.0105-2896.2006.00346.x.
Because of the use of somewhat artificial models for the elucidation of negative selection [superantigen, T-cell receptor (TCR) transgenic mice], there is still considerable uncertainty at what stages of T-cell development negative selection can occur and whether it becomes manifest as developmental arrest, lineage diversion, or induction of apoptotic cell death. Here, experimental evidence is reviewed that excludes developmental arrest and lineage diversion as the sole mechanisms of negative selection. The data emphasize that both CD4+ CD8+ double-positive cortical as well as semi-mature, single-positive, medullary thymocytes are targets of deletion in experimental models employing superantigen and TCR transgenic mice with premature as well as 'timely' onset of TCR expression.
由于在阐明阴性选择时使用了某种程度上人为构建的模型（超抗原、T细胞受体转基因小鼠），对于T细胞发育的哪些阶段会发生阴性选择以及它是否表现为发育停滞、谱系转换或凋亡性细胞死亡的诱导，仍然存在相当大的不确定性。在此，我们回顾了排除发育停滞和谱系转换作为阴性选择唯一机制的实验证据。数据强调，在使用超抗原以及TCR过早表达和“适时”表达的TCR转基因小鼠的实验模型中，CD4+CD8+双阳性皮质胸腺细胞以及半成熟的单阳性髓质胸腺细胞都是被清除的目标。
