Oscillatory expression of lentiviral transgenes

虽然抗逆转录病毒药物可以使感染艾滋病毒的人恢复正常的预期寿命，但他们一生中仍然会有感染艾滋病毒的细胞，这些细胞会产生病毒，损害他们的健康。相比之下，在基因治疗技术领域，被基因指示持续制造慢病毒的细胞经常使其病毒基因失活并停止制造病毒，从而影响基因治疗生产的有效性。该项目旨在模拟、设计、构建和测试一个“病毒振荡器”遗传电路，以延长稳定的慢病毒包装细胞的生产寿命。所得到的细胞的性能将与传统的稳定慢病毒包装细胞系进行测试。尽管HIV-1基因的高水平表达会导致细胞死亡，但天然慢病毒HIV-1可以在被感染的人体内持续产生感染性病毒颗粒长达数十年。从该系统的数学建模中获得的见解表明，两个HIV-1基因的相反功能分别作为正反馈回路和负反馈回路，导致病毒基因整体振荡。通过这种方式，慢病毒基因产物的生产速度是不断变化的，随着时间的推移，慢病毒蛋白的产量足够高，但从来没有保持在细胞毒性生产速度足够长的时间来选择细胞反应。这个项目将测试一个假设，即慢病毒基因的工程振荡可以延长稳定的慢病毒包装细胞系的生产寿命。

Although antiretroviral drugs can give people a normal life expectancy after HIV infection, they will still have HIV-infected cells throughout their life that make viruses and compromise their health. By contrast, in the field of gene therapy technology, cells that have been genetically instructed to continually make lentivirus frequently inactivate their viral genes and stop making virus, compromising the effetiveness of gene therapy production. The project aims to model, design, build and test a 'viroscillator' genetic circuit to extend the productive lifespan of stable lentiviral packaging cells. The performance of the resulting cells will be tested against conventional stable lentiviral packaging cell lines. The natural lentivirus, HIV-1, can achieve robust, persistent production of infectious viral particles in infected humans over decades, despite the fact high levels of expression of HIV-1 genes can lead to cell death. Insights gained from mathematical modelling of this system suggested opposing function of two HIV-1 genes act as positive and negative feedback loops respectively to bring about oscillation of viral genes overall. In this way the rate of production of lentiviral genes products is in constant flux, achieving sufficient yield of lentiviral protein over time, but never remaining at cytoxic production rate for long enough to select for a cell response. This project will test the hypothesis that an engineered oscillation of lentiviral genes can extend the productive lifespan of a stable lentiviral packaging cell lines.