Centre for Virus Research, The Westmead Institute for Medical Research, The University of Sydney, 176 Hawkesbury Road, Westmead, NSW, 2145, Australia.
Retrovirology. 2018 Jan 9;15(1):3. doi: 10.1186/s12977-017-0386-x.
Antiretroviral therapy effectively suppresses, but does not eradicate HIV-1 infection. Persistent low-level HIV-1 can still be detected in plasma and cellular reservoirs even after years of effective therapy, and cessation of current treatments invariably results in resumption of viral replication. Efforts to eradicate persistent HIV-1 require a comprehensive examination of the quantity and genetic composition of HIV-1 within the plasma and infected cells located in the peripheral blood and tissues throughout the body. Single-molecule techniques, such as the single-copy assay and single-genome/proviral sequencing assays, have been employed to further our understanding of the source and viral dynamics of persistent HIV-1 during long-term effective therapy. The application of the single-copy assay, which quantifies plasma HIV-1 RNA down to a single copy, has revealed that viremia persists in the plasma and CSF after years of effective therapy. This low-level HIV-1 RNA also persists in the plasma following treatment intensification, treatment with latency reversing agents, cancer-related therapy, and bone marrow transplantation. Single-genome/proviral sequencing assays genetically characterise HIV-1 populations after passing through different selective pressures related to cell type, tissue type, compartment, or therapy. The application of these assays has revealed that the intracellular HIV-1 reservoir is stable and mainly located in CD4+ memory T cells. Moreover, this intracellular HIV-1 reservoir is primarily maintained by cellular proliferation due to homeostasis and antigenic stimulation, although cryptic replication may take place in anatomic sites where treatment is sub-optimal. The employment of single-genome/proviral sequencing showed that latency reversing agents broadly activate quiescent proviruses but do not clear the intracellular reservoir. Recently, full-length individual proviral sequencing assays have been developed and the application of these assays has revealed that the majority of intracellular HIV-1 DNA is genetically defective. In addition, the employment of these assays has shown that genetically intact proviruses are unequally distributed in memory T cell subsets during antiretroviral therapy. The application of single-molecule assays has enhanced the understanding of the source and dynamics of persistent HIV-1 in the plasma and cells of HIV-infected individuals. Future studies of the persistent HIV-1 reservoir and new treatment strategies to eradicate persistent virus will benefit from the utilization of these assays.
抗逆转录病毒疗法可有效抑制，但不能根除 HIV-1 感染。即使经过多年有效的治疗，血浆和细胞储库中仍能检测到持续存在的低水平 HIV-1，并且停止当前的治疗总是会导致病毒复制的恢复。根除持续性 HIV-1 需要全面检查体内血浆和外周血及组织中感染细胞中 HIV-1 的数量和遗传组成。单分子技术，如单拷贝检测和单基因组/前病毒测序检测，已被用于进一步了解在长期有效治疗期间持续性 HIV-1 的来源和病毒动力学。单拷贝检测可定量检测到单个拷贝的血浆 HIV-1 RNA，该检测显示，即使经过多年有效的治疗，病毒血症仍存在于血浆和 CSF 中。在强化治疗、潜伏期逆转剂治疗、癌症相关治疗和骨髓移植后，这种低水平的 HIV-1 RNA 也会持续存在于血浆中。单基因组/前病毒测序检测通过对与细胞类型、组织类型、隔室或治疗相关的不同选择压力下的 HIV-1 群体进行基因特征分析。这些检测的应用表明，细胞内 HIV-1 库是稳定的，主要位于 CD4+记忆 T 细胞中。此外，由于体内平衡和抗原刺激，细胞增殖主要维持了细胞内 HIV-1 库，尽管隐匿性复制可能发生在治疗效果不佳的解剖部位。单基因组/前病毒测序检测表明，潜伏期逆转剂广泛激活静止的前病毒，但不能清除细胞内储库。最近，已经开发出全长个体前病毒测序检测，这些检测的应用表明，大多数细胞内 HIV-1 DNA 存在遗传缺陷。此外，这些检测的应用表明，在抗逆转录病毒治疗期间，遗传完整的前病毒在记忆 T 细胞亚群中的分布不均等。单分子检测的应用增强了对 HIV 感染者血浆和细胞中持续性 HIV-1 的来源和动力学的理解。对持续性 HIV-1 储库的未来研究和根除持续性病毒的新治疗策略将受益于这些检测的应用。
