A radiation-induced cellular stress activates HIV and induces killing of infected cells

辐射引起的细胞应激会激活艾滋病毒并诱导杀死受感染的细胞

• 批准号: 9212863
• 负责人: Fatah Kashanchi
• 金额: $ 19万
• 依托单位: GEORGE MASON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-15 至 2018-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9212863
• 关键词: Agonist; Anti-Retroviral Agents; Apoptosis; Autophagocytosis; Binding; CASP1 gene; CD4 Positive T Lymphocytes; Cell Culture Techniques; Cell Cycle; Cell Death; Cell Line; Cell Survival; Cells; Cellular Stress; Cessation of life; Cyclins; DNA Damage; DNA Polymerase II; Data; Dose; Epigenetic Process; Genetic Transcription; Genome; Goals; HDAC1 gene; HIV; HIV-1; Highly Active Antiretroviral Therapy; Human; Immune response; Immune system; Individual; Induction of Apoptosis; Interleukin-7; Life; Methods; Mus; Nuclear; Organ; Outcome; Patients; Pharmaceutical Preparations; Phosphorylation; Plasma; Population; Positive Transcriptional Elongation Factor B; Production; Proteasome Inhibitor; Publishing; RNA; RNA Polymerase II; Radiation; Rest; Reverse Transcriptase Polymerase Chain Reaction; Roentgen Rays; S Phase; Scheme; Shock; Signal Transduction; Specificity; Stress; T-Lymphocyte; TP53 gene; Testing; Therapeutic; Tissues; Transcriptional Activation; Transferase; Viral; Viral Proteins; Viral reservoir; Virus; Virus Replication; Western Blotting; Work; bryostatin; calpain inhibitor; cancer therapy; chromatin immunoprecipitation; cytotoxic; humanized mouse; in vivo; inhibitor/antagonist; irradiation; killings; macrophage; promoter; repaired; response; transcription factor; viral RNA

HIV-1 can be preserved in the long-lived resting CD4+ T cells which form a viral reservoir in infected individuals. This reservoir may persist for many years even though the patients are usually treated with highly active antiretroviral therapy (HAART), and viral population can be recovered once HAART is stopped. Thus, the selective activation of the latently HIV-infected cells resulting in the replication of proviral genome is critical to make infected cells recognized by immune system. Our long term goal is to find the method of reactivation of HIV from latency and killing of infected cells that does not kill or destroy non-infected quiescent cells and subsequently target and eradicate the persistent HIV-1 reservoirs. We have preliminary data showing that a well-characterized stress signal, such as irradiation (IR), activated inappropriate entry of the HIV infected T cells to S phase of the cell cycle and increased viral transcription and eventual apoptosis of infected cells. Importantly, the parental uninfected cells did not demonstrate this response to the same irradiation dose. Our recently published data elucidated this phenomenon and indicated (1) increase of HIV-1 transcription via epigenetic mechanisms after the IR-induced DNA damage, as evidenced by the presence of RNA polymerase II and reduction of HDAC1 and methyl transferase SUV39H1 on the HIV-1 promoter; (2) elevated level of intracellular HIV-1 RNA and increased expression of viral proteins in the IR-treated HIV-1 infected quiescent CD4+ T cells; (3) enhancement of transcription activation in latently HIV-1infected macrophages treated with PKC agonist bryostatin 1 after IR; (4) higher death of irradiated HIV-1 chronically-infected cells via increased phosphorylation of Ser46 in p53 that is responsible for apoptosis induction. Finally, (5) exposure of HIV-1 infected humanized mice with undetectable viral RNA level to IR resulted in a significant increase of HIV-1 RNA in plasma and certain tissue viral reservoirs. We hypothesize, that the cellular stress induced by low IR doses reactivates HIV-1 transcription from latently infected cells resulting in nuclear accumulation of Tat, activation of HIV-1 genome expression and enhanced apoptosis of infected, but not uninfected, cells. Our two aims include; A) To identify the mechanism of HIV-1 reactivation in response to therapeutic X-ray doses in latently infected T cells and to assess IR effect on the Tat activated HIV-1 transcription; and B) To decipher mechanism of enhanced apoptosis of HIV-1 infected cells in response to IR doses. The expected outcomes of these proposed studies include elucidation of the mechanisms that determine HIV-1 reactivation and apoptosis in latently infected cells and tissues in response to the X ray IR. We also expect to determine optimal IR dose that does not destroy uninfected cells, but induces HIV-1 reactivation and apoptosis of latently infected cells.

HIV-1 可以保存在长寿命的静息 CD4+ T 细胞中，这些细胞在感染者体内形成病毒库 个人。即使患者通常接受治疗，这种病毒库仍可能持续多年 高效抗逆转录病毒治疗（HAART），病毒数量一旦恢复即可 HAART 已停止。因此，潜在 HIV 感染细胞的选择性激活导致 原病毒基因组的复制对于使受感染的细胞被免疫系统识别至关重要。我们的 长期目标是找到从潜伏期重新激活HIV并杀死受感染细胞的方法 不会杀死或破坏未感染的静止细胞，并随后瞄准并根除 持久性 HIV-1 病毒库。我们有初步数据表明，一个明确表征的压力 信号，如辐射 (IR)，激活了 HIV 感染的 T 细胞不适当地进入 S 期 细胞周期和增加的病毒转录以及受感染细胞的最终凋亡。重要的是， 未受感染的亲本细胞并未表现出对相同辐射剂量的这种反应。我们的 最近发表的数据阐明了这一现象，并表明 (1) HIV-1 增加 IR 诱导的 DNA 损伤后通过表观遗传机制进行转录，如 RNA 聚合酶 II 的存在以及 HDAC1 和甲基转移酶 SUV39H1 的减少 HIV-1启动子； (2)细胞内HIV-1 RNA水平升高，病毒表达增加 IR 处理的 HIV-1 感染的静态 CD4+ T 细胞中的蛋白质； (3)转录的增强 IR 后用 PKC 激动剂苔藓抑素 1 处理的潜伏 HIV-1 感染巨噬细胞的激活； (4) 受辐射的 HIV-1 慢性感染细胞通过增加 Ser46 的磷酸化而导致更高的死亡 p53 负责诱导细胞凋亡。最后，（5）暴露HIV-1感染者人源化 IR 检测不到病毒 RNA 水平的小鼠导致 HIV-1 RNA 显着增加 血浆和某些组织病毒库。我们假设，低 IR 诱导的细胞应激 剂量重新激活潜伏感染细胞中的 HIV-1 转录，导致核积聚 Tat，激活HIV-1基因组表达并增强感染者而非未感染者的细胞凋亡， 细胞。我们的两个目标包括： A) 确定 HIV-1 重新激活的机制 潜伏感染 T 细胞的治疗 X 射线剂量，并评估 IR 对 Tat 激活的 HIV-1 的影响 转录； B) 破译 HIV-1 感染细胞凋亡增强的机制 对红外剂量的反应。这些拟议研究的预期结果包括阐明 决定潜伏感染细胞和组织中 HIV-1 重新激活和凋亡的机制 对 X 射线 IR 的响应。我们还期望确定不会破坏的最佳红外剂量 未感染的细胞，但诱导 HIV-1 重新激活和潜在感染细胞的凋亡。