The effect of HIV and cocaine abuse on semen exosome composition and function

摘要 艾滋病大流行仍然是一个重大的全球问题，目前有3330多万人 感染艾滋病毒和艾滋病毒相关疾病每年夺走180多万人的生命。 各种研究表明，包括可卡因在内的非法药物滥用与 艾滋病毒传播的风险、艾滋病毒疾病加速发展和艾滋病相关死亡。女人 代表了新增艾滋病毒病例中增长最快的人群。据估计，超过80%的艾滋病毒 病例是由性传播引起的，精液是主要媒介。然而，只有约0.1%的 与感染者的异性性交行为会导致艾滋病毒感染，这表明 精液中含有的艾滋病毒颗粒可能会调节精液中艾滋病毒颗粒的传染性或适合性。潜在的 艾滋病毒的传播机制还没有被很好地理解。尽管艾滋病毒的研究取得了进展 发病机制和各种药物抑制病毒感染的能力，预防艾滋病毒的方法 传播仍然需要更多的调查。最近，我们发现健康捐赠者的精液 包含大小在形态上截然不同的外体的异源群体 和电子密度。这些外体含有不同种类的RNA(mRNA和小RNA)，以及 抑制艾滋病毒感染。我们的初步数据显示，类似于猪精液中的外小体 健康的捐赠者，从感染艾滋病毒的捐赠者中提纯的外切体可以有效地阻止艾滋病毒感染，同时 来自使用可卡因的艾滋病毒感染捐赠者的外切体不能抑制艾滋病毒。我们的初步研究进一步 研究表明，HIV感染和可卡因的使用调节了精液外切体的RNA组成。 重要的是，来自HIV阴性和HIV感染捐赠者的裂解精液外切体，但不是捐赠者 世卫组织使用可卡因在无细胞系统中抑制裂解艾滋病毒的逆转录，阻断合成 HIV U5 DNA，并将U5逆转录为Gag。这些数据表明精液的直接作用 外显子对HIV逆转录的影响。在此应用中，研究旨在1)确定 HIV感染和可卡因滥用对精液外精子抗HIV活性的影响，2)测定 精液外切体抗HIV作用的机制，以及3)供体HIV作用的表征 精液外精体成分的现状及可卡因使用情况。由于性传播是性传播的主要途径 艾滋病毒和精液的传播是主要媒介，本申请中提出的研究将 精液外渗体作为保护因子的有效性评估面临的新挑战 以及捐赠者艾滋病毒状况和可卡因使用如何调节这一功能。

Abstract The AIDS pandemic remains a significant global problem with over 33.3 million persons currently infected with HIV and HIV-related illnesses claiming the lives of over 1.8 million individuals annually. Various studies have suggested a link between abuse of illicit drugs, including cocaine and increased risk of HIV transmission, accelerated HIV disease progression, and AIDS-related mortality. Women represent the fastest growing population of new HIV cases. It is estimated that more than 80% of HIV cases result from sexual transmission and semen is the primary vector. However, only about 0.1% of acts of heterosexual coitus with an infected individual result in HIV infection, suggesting that factors contained in semen may modulate the infectivity or fitness of HIV particles in semen. The underlying mechanisms of HIV transmission are not well understood. In spite of the progress in studies of HIV pathogenesis and the ability of various agents to suppress virus infection, methods to prevent HIV transmission still require more investigation. Recently, we showed that semen of healthy donors contain heterologous populations of exosomes that are morphologically distinct with respect to size and electron density. These exosomes contain different species of RNA (mRNA and small RNA), and inhibit infection with HIV. Our preliminary data reveal that similar to exosomes from the semen of healthy donors, exosomes purified from HIV infected donors potently block HIV infection while exosomes from HIV infected donors who use cocaine do not inhibit HIV. Our preliminary study further showed that HIV infection and cocaine use modulates RNA composition of semen exosomes. Importantly, lysed semen exosomes from both HIV negative and HIV infected donors but not donors who used cocaine inhibit reverse transcription of lysed HIV in a cell-free system, block the synthesis of HIV U5 DNA, and reverse transcription of U5 to Gag. These data indicate direct effect of semen exosomes on HIV reverse transcription. In this application, studies are designed to 1) determine the effect of HIV infection and cocaine abuse on the anti-HIV activity of semen exosomes, 2) determine the mechanisms of anti-HIV effect of semen exosomes, and 3) characterize the effects of donor HIV status and cocaine use on semen exosome composition. As sexual transmission is the main route for the spread of HIV and semen is the primary vector, the studies proposed in this application will address a new challenge for evaluation of the efficacy of semen exosomes as a protective factor against HIV and how donor HIV status and cocaine use modulate this function.