Tripp R A, Hou S, McMickle A, Houston J, Doherty P C
Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
J Immunol. 1995 Jun 1;154(11):6013-21.
The dramatic increase in the cellularity of the mediastinal lymph nodes (MLN) of mice infected intranasally (i.n.) with influenza viruses is a consequence of both recruitment and proliferation. As many as 20% of the CD8+ subset in the MLN can be shown to be in S or G2 + M phase at 6 days after i.n. challenge with the HKx31 influenza A virus, the percentage of of cycling cells being approximately five times greater for the activated/memory substantial evidence of apoptosis was found for CD8+ T cells recovered from the MLN and lung, particularly at 5 and 7 days after infection. Less than 1/100 of the proliferating T cells could be shown, by limiting dilution analysis (LDA), to be influenza virus-specific CD8+ cytotoxic T lymphocyte precursors (CTLp). A single, low dose (20 mg/kg) of the DNA-targeted drug cyclophosphamide (Cy) caused a massive decrease in frequency for the responding CD8+ CTLp, though the mice survived infection with the HKx31 virus and there was no long-term exhaustion of the CTLp pool in the MLN, spleen, or lung. The Cy treatment was also followed by a smaller reduction in the prevalence of memory CTLp (specific for Sendai virus) that were present concurrently in the regional lymph node, indicating that a measure of bystander activation is occurring. The experiments show that respiratory virus infections have no negative impact on established T cell memory, and that there is no phase of transient exhaustion in the acute virus-specific CTLp response in this localized infection.
经鼻内（i.n.）感染流感病毒的小鼠纵隔淋巴结（MLN）细胞数量急剧增加是募集和增殖共同作用的结果。在用甲型流感病毒HKx31经鼻内攻击后6天，MLN中多达20%的CD8 + 亚群可显示处于S期或G2 + M期，对于活化/记忆性CD8 + T细胞，循环细胞的百分比大约是未活化细胞的五倍。从MLN和肺中回收的CD8 + T细胞存在大量凋亡证据，尤其是在感染后5天和7天。通过有限稀释分析（LDA）表明，增殖的T细胞中不到1/100是流感病毒特异性CD8 + 细胞毒性T淋巴细胞前体（CTLp）。单次低剂量（20 mg/kg）的DNA靶向药物环磷酰胺（Cy）导致应答性CD8 + CTLp的频率大幅下降，尽管小鼠在感染HKx31病毒后存活，且MLN、脾脏或肺中的CTLp库没有长期耗竭。Cy处理后，区域淋巴结中同时存在的记忆性CTLp（针对仙台病毒）的患病率也有较小程度的降低，这表明存在一定程度的旁观者活化。实验表明，呼吸道病毒感染对已建立的T细胞记忆没有负面影响，并且在这种局部感染的急性病毒特异性CTLp反应中不存在短暂耗竭阶段。
