Transcriptional activation of the HTLV-I gene in monocytes and macrophages.

单核细胞和巨噬细胞中 HTLV-I 基因的转录激活。

基本信息

批准号：
13671089
负责人：
TSUKADA Junichi
金额：
$ 2.3万
依托单位：
University of Occupational and Environmental Health, Japan
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2003
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13671089/
关键词：
HTLV-I adult T-cell leukemia Tax HTLV-I リポポリサッカライド成人T細胞性白血病

HTLV-I adult T-cell leukemia Tax HTLV-I リポポリサッカライド成人T細胞性白血病

项目摘要

The human T-cell leukemia virus type I (HTLV-I) is the etiologic agent of an aggressive form of human malignancy, adult T-cell leukemia/lymphoma (ATLL) and is also associated with many inflammatory diseases including myelopathy/tropical spastic paraparesis (HAM/TSP), arthropathy (HAAP), bronchopneumonopathy (HAB), uveitis and Sjogren syndrome. HTLV-I infection is widely distributed among mammalian cells including B lymphocytes, monocyte/macrophage cells and fibroblasts. Monocyte/macrophage cells are versatile secretory cells able to release various kinds of cytokines which contribute substantially to host defence and inflammation. Recently, HTLV-I-infected monocyte/macrophage cells from patients with ATLL or HAM/TSP have been demonstrated to participate in various pathological events in ATLL and HTLV-I-associated inflammatory diseases. In addition, a recent paper has shown that IL-2 production by primary ATLL cells is macrophage-dependent.In the present study, we clarified cell-type sp … More ecific transcriptional activation of the HTLV-I LTR in monocytes. CAT reporters containing the HTLV-I LTR were transfected into THP-1 monocytes. As a result, LPS as well as p40Tax dose-dependently activated the HTLV-I LTR in monocytes. The LTR possesses 3 GGAA motifs, PuB1, PET and PuB2. Mutation studies further showed that 2 GGAA motifs, PET and PuB2 are essential to the LPS induction of the LTR in monocytes. In contrast, Tax-induction of the LTR in T-cells did not require either PuB2 or PET. These results demonstrate that GGAAs within the LTR are monocyte-specific LPS-responsive elements. Our EMSA data using a PuB2 probe and LPS-stimulated THP-1 nuclear extracts revealed binding of PU.1 (Spi-1), an Ets family transcription factor to PuB2, showing the importance of PU.1 binding in LPS-induction of the LTR in monocytes. In vitro translated recombinant PU.1 also bound to PET. Moreover, any Ets proteins including PU.1 did not bind to the PuB2 sequence. Interestingly, the THP-1 nuclear extract/PuB2 complex migrated significantly slower than recombinant PU.1/PuB2 complex did. Anti-IRF-8 Ab supershifted the slow complex, showing IRF-8, a co-factor for PU.1 is involved in the slow complex. Based upon the results obtained in the present study, the LTR of the HTLV-I gene is a LPS-responsive element recognized by PU.1 in monocytes. We propose cell-type specific transcriptional regulation of the HTLV-I gene in monocytes and T-cells. Less

人类T细胞白血病I型（HTLV-I）是人类恶性肿瘤，成人T细胞白血病/淋巴瘤（ATLL）的侵略性形式的病因，也与许多炎症性疾病有关综合征。 HTLV-I感染广泛分布在包括B淋巴细胞，单核细胞/巨噬细胞和成纤维细胞的哺乳动物细胞之间。单核细胞/巨噬细胞是多功能的秘密细胞，可以释放各种细胞因子，这些细胞因子对宿主防御和炎症有很大贡献。最近，已经证明，来自ATLL或HAM/TSP患者的HTLV-I感染的单核细胞/巨噬细胞已参与ATLL和HTLV-I-I-I-I-I-I-I-I-I-I-I-I-I-I-I-I-I-Camped炎症性疾病的各种病理事件。此外，最近的一篇论文表明，原代ATLL细胞的IL-2产生是巨噬细胞的依赖性。在本研究中，我们将单核细胞中HTLV-I LTR的细胞类型SP熔融了。将含有HTLV-I LTR的CAT记者翻译成Thp-1单核细胞。结果，LPS以及P40TAX剂量依赖性地激活了单核细胞中的HTLV-I LTR。 LTR具有3个GGAA图案，Pub1，PET和Pub2。突变研究进一步表明，2个GGAA基序，PET和PUB2对于单核细胞中LTR的LPS诱导至关重要。相反，T细胞中LTR的税收诱导不需要Pub2或PET。这些结果表明，LTR内的GGAA是单核细胞特异性LPS响应元件。我们使用Pub2探针和LPS刺激的THP-1核提取物的EMSA数据显示，PU.1（SPI-1）的结合是ETS家族转录因子与Pub2的结合，显示了PU.1在单核细胞中LPR诱导LPS诱导中的重要性。体外翻译重组PU.1也与PET结合。此外，包括PU.1在内的任何ETS蛋白都不与Pub2序列结合。有趣的是，THP-1核提取物/Pub2复合物的迁移明显慢于重组PU.1/pub2复合物。抗IRF-8 AB超速移动缓慢的复合物，显示了IRF-8，PU.1的co coctor涉及慢速复合物。根据本研究中获得的结果，HTLV-I基因的LTR是单核细胞中PU.1识别的LPS响应元件。我们提出了单核细胞和T细胞中HTLV-I基因的细胞类型特异性转录调节。较少的