Clinical Core

2007年估计有3 300万艾滋病毒携带者，210万人死于艾滋病，全世界每年新增250万艾滋病毒感染者，艾滋病毒-1和艾滋病的全球影响仍然是压倒性的，尽管发展中国家在治疗艾滋病毒-1慢性感染方面取得了进展，获得治疗的机会也有所改善--即使在流行程度与发展中国家相比相形见绌的美国，艾滋病毒-1感染已对健康和社会产生了重大影响：2007年，估计有130万艾滋病毒-1感染者，56 000人新感染[1，2]。病毒学和免疫学数据与疫苗等生物医学预防策略的发展密切相关，至关重要。 3.1艾滋病毒-1的性传播与病毒的相关性。与性传播相关最强的病毒是血浆HIV-1RNA水平[3，4]。血浆和生殖器分泌物[5，6]和精浆中的HIV RNA水平与传播概率[7，8]相关。最近的数据表明，与血浆相比，生殖器分泌物中可能富含不同的病毒变体，尽管数据相互矛盾[9-12]。多年来对性传播的许多研究表明，感染艾滋病毒-1 B亚型的人通常(目前估计为70-80[13，14，15])来自单一病毒创始人。然而，最近感染了A或D亚型HIV-1的非洲异性恋女性和男性的数据显示，32名女性中有20名携带多种病毒变种，而所有研究的10名男性都只有一种变种。这些数据表明，感染者或病毒亚型的性别可能会改变传播病毒的特征。 其他研究表明，其他病毒特征，如包膜糖蛋白N连接的糖基化或包膜长度可能会影响传播性，尽管这可能是亚型特有的[2021](更详细的讨论见项目1和3)。

With an estimated 33 million persons living with HIV-1, 2.1 millions deaths from AIDS in 2007, and 2.5 million new HIV-1 infections per year worldwide, the global impact of HIV-1 and AIDS continues to be overwhelming, despite advances in treatment of chronic HIV-1 infection and improved access to treatment in developing countries\ Even in the United States, whose epidemic is dwarfed by that in developing countries, HIV-1 infection has had major health and social impacts: an estimated 1.3 million persons were living with HIV-1 infection and 56,000 people were newly infected in 2007[1,2]. Virologic and immunologic data germane to development of biomedical preventative strategies such as vaccines is critically important. 3.1 Viral Correlates of Sexual Transmission of HIV-1. The strongest viral correlate of sexual transmission has been plasma HiV-1 RNA levels[3,4]. HIV RNA levels in plasma and genital secretions correiate[5,6] and seminal plasma have been correlated with transmission probability[7,8]. More recent data suggest that distinct viral variants may be enriched in genital secretions compared with blood plasma although data are conflicting [9-12]. Many studies of sexual transmission over the years have shown that infections with HIV-1 subtype B typically (current estimates are ¿¿70-80[13,14,15]) originate from single virus founders. However, data from heterosexual African women and men who had recently acquired HIV-1 subtypes A or D demonstrated that 20 of 32 women had multiple viral variants whereas all 10 of the men studied had a single variant^^. These data suggest that sex of the Infected individual or viral subtype might modify the characteristics of the transmitted virus. Other studies have suggested that other viral characteristics such as such as env glycoprotein N-llnked glycosylation or env lengths may impact transmissibility^^'^^, though again this may be subtype-specific[2021] (see Projects 1 and 3 for more detailed discussions).