Cossarizza A, Kahan M, Ortolani C, Franceschi C, Londei M
Charing Cross Sunley Research Centre, London, GB.
Eur J Immunol. 1991 Jun;21(6):1571-4. doi: 10.1002/eji.1830210637.
The peripheral T cell receptor repertoire is mainly controlled by the processes of positive and negative selection occurring in the thymus. Studies in normal or transgenic mice have provided compelling evidence for both negative and positive selection. Negative selection is characterized by partial or total disappearance from the periphery of T cells expressing certain C beta regions, which are normally present in the thymus. Positive selection is chiefly characterized, in the periphery, by an imbalanced ratio between CD4+ and CD8+ T cells expressing a given V domain. To date little information concerning positive and negative selection has been available in man. We studied the distribution of 4 V beta domains on CD4+ and CD8+ peripheral T cells of 34 healthy individuals with a wide age-range (0-96 years). One of the V beta domain studied, V beta 6.7, is preferentially expressed on CD4+ compared to CD8+ T cells (p greater than 0.001). No significant differences were observed using the other V beta domain-specific monoclonal antibodies (V beta 5.2-5.3, 8 or 12). These results provide evidence that a process of thymic education, similar to that described in murine animal models, may also take place in man.
外周T细胞受体库主要受胸腺中发生的阳性和阴性选择过程控制。对正常或转基因小鼠的研究为阴性和阳性选择都提供了令人信服的证据。阴性选择的特征是表达某些Cβ区域的T细胞在胸腺中正常存在，但在外周部分或全部消失。阳性选择在外周的主要特征是表达特定V结构域的CD4+和CD8+T细胞之间比例失衡。迄今为止，关于人类阳性和阴性选择的信息很少。我们研究了34名年龄范围广泛（0-96岁）的健康个体外周CD4+和CD8+T细胞上4种Vβ结构域的分布。所研究的Vβ结构域之一Vβ6.7，与CD8+T细胞相比，在CD4+T细胞上优先表达（p>0.001）。使用其他Vβ结构域特异性单克隆抗体（Vβ5.2-5.3、8或12）未观察到显著差异。这些结果提供了证据，表明类似于在小鼠动物模型中描述的胸腺教育过程也可能在人类中发生。
