Purvis S F, Georges D L, Williams T M, Lederman M M
Department of Environmental Health Sciences, Case Western Reserve University School of Medicine, University Hospitals of Cleveland, Ohio 44106.
Cell Immunol. 1992 Oct 1;144(1):32-42. doi: 10.1016/0008-8749(92)90223-c.
The Jurkat T cell line was stably transfected with an Epstein-Barr virus-based episomal replicon designed to express high levels of the HIV-1 Tat protein. After selection in hygromycin B, high-level Tat activity was detected in 3 of 18 transfected cell lines. After stimulation with phytohemagglutinin (PHA) and phorbol myristate acetate (PMA), Tat transfectants with high Tat expression showed diminished expression of interleukin-2 (IL-2) and the interleukin-2 receptor alpha chain (IL-2R) when compared to untransfected Jurkat cells or Jurkat cell lines transfected with the parent control plasmid. Sublines derived from the high-level Tat transfectants with reduced Tat activity showed normalization of PHA/PMA-induced IL-2 expression. Northern analysis showed diminished expression of IL-2 and IL-2R mRNA in the stimulated Tat transfectants. Inhibition of IL-2 and IL-2R expression by the HIV-1 Tat protein may contribute to the immune suppression that characterizes HIV-1 infection.
用一种基于爱泼斯坦-巴尔病毒的游离复制子稳定转染Jurkat T细胞系，该复制子设计用于高水平表达HIV-1 Tat蛋白。在潮霉素B中筛选后，在18个转染细胞系中的3个中检测到高水平的Tat活性。在用植物血凝素（PHA）和佛波酯（PMA）刺激后，与未转染的Jurkat细胞或用亲本对照质粒转染的Jurkat细胞系相比，高Tat表达的Tat转染子显示白细胞介素-2（IL-2）和白细胞介素-2受体α链（IL-2R）的表达减少。从具有降低的Tat活性的高Tat转染子衍生的亚系显示PHA/PMA诱导的IL-2表达正常化。Northern分析显示，在受刺激的Tat转染子中IL-2和IL-2R mRNA的表达减少。HIV-1 Tat蛋白对IL-2和IL-2R表达的抑制可能导致了HIV-1感染所特有的免疫抑制。
