Tripp R A, Hou S, Doherty P C
Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
J Immunol. 1995 Jun 1;154(11):5870-5.
Whether the L-selectin-low (L-sel-lo) phenotype of acutely stimulated CD8+ T cells is a permanent characteristic of long-term memory CTL precursors (p) is addressed for mice primed with an influenza A virus or the murine parainfluenza type 1 virus, Sendai virus. In both cases, many of the splenic CD8+ CTLp gradually lose the predominantly L-sel-lo profile associated with recently generated CTLp populations. The influenza-specific CTLp also tend to revert from the activated alpha 4-integrin-high to the resting alpha 4-integrin-low form. The kinetics of the switch back to the "naive" L-sel-hi phenotype differs for the influenza and Sendai virus models, perhaps reflecting events occurring during the acute phases of these responses. The return to being L-sel-hi is not due to irreversible lymphocyte senescence, because restimulation of this set with the inducing virus in vitro causes most of the cells to become L-sel-lo. Also, despite the time-related drift of these particular memory CTLp to the L-sel-hi state, the size of the total pool of L-sel-lo CD8+ T cells increases with age.
对于用甲型流感病毒或1型鼠副流感病毒（仙台病毒）免疫的小鼠，研究了急性刺激的CD8 + T细胞的低L-选择素（L-sel-lo）表型是否是长期记忆性CTL前体（p）的永久特征。在这两种情况下，许多脾CD8 + CTLp逐渐失去与最近产生的CTLp群体相关的主要L-sel-lo特征。流感特异性CTLp也倾向于从活化的高α4整合素形式转变为静止的低α4整合素形式。在流感和仙台病毒模型中，恢复到“幼稚”的高L-选择素表型的动力学有所不同，这可能反映了这些反应急性期发生的事件。恢复到高L-选择素状态并非由于淋巴细胞不可逆的衰老，因为在体外用诱导病毒重新刺激这群细胞会使大多数细胞变为低L-选择素。此外，尽管这些特定的记忆性CTLp随时间漂移至高L-选择素状态，但低L-选择素CD8 + T细胞的总库大小会随着年龄的增长而增加。
