Oral HIV Pathogenesis and Shedding

描述(由申请人提供)：感染艾滋病毒的主要部位是粘膜表面。虽然流行病学数据表明，艾滋病毒经口传播并不常见，但可以在口腔分泌物中发现艾滋病毒。在口咽部HIV脱出的初步研究中，我们检查了来自西雅图和秘鲁的70名HIV+男性，他们的CD4中位数为356个/mUL；52%的人正在接受高效抗逆转录病毒治疗(HAART)。每周采集血液和口咽拭子，并对其进行HIV RNA检测。20名男性(29%)在舌拭子和/或咽拭子中检测到艾滋病毒RNA(VRNA)。广义估计方程显示，血浆VL每增加1.0log10与咽部VL增加0.4log10相关(P&lt；0.001)，扁桃体切除术与咽部VL每减少0.6log10相关(P=0.007)，而HAART不相关(P&gt；0.1)。在20例vRNA阳性男性中，有5例(25%)从口咽后部分离到感染性HIV。培养阳性组粘膜VL中位数为6.35log10拷贝/ml，培养阴性组为4.68log10拷贝/ml(P=0.06)。未从唾液、口腔或唾液粘膜中分离到HIV。腭扁桃体和舌扁桃体活检(n=6)在淋巴滤泡内发现vRNA和p24抗原，尽管HAART抑制了血浆VL。VRNA+细胞靠近扁桃体包膜并在扁桃体包膜内迁移。HIV vRNA存在于扁桃体淋巴细胞、巨噬细胞(Mphi)和较少的树突状细胞(DC)中。粘膜CCR5+淋巴细胞是最常见的vRNA+“暗淡”的Mphi，通常携带10倍以上的vRNA和传染性病毒。对口咽病毒的检查显示出比同时检查的血液病毒更多的env基因多样性，特别是在接受HAART的男性患者中(P=0.004)。这些研究表明，口咽是HIV表达的部位，在那里Mphi似乎在维持高滴度的复制型HIV方面发挥着重要作用。先前存在的口腔病理和促进与舌咽粘膜接触的性行为可能与病毒传播的风险增加有关。这项建议致力于确定口咽部艾滋病毒感染的发病机制，并将重点确定支持艾滋病毒复制的解剖部位(S)和细胞，以及影响粘膜表面病毒频率和滴度的因素。它使用最先进的方法，并描述了体外研究和体内研究的结合，使用扁桃体外植体来研究感染的动力学，以及体内研究来评估可能是口腔独有的艾滋病毒种群动态，包括耐药病毒的“区隔”。

DESCRIPTION (provided by applicant): The primary sites of acquisition of HIV are at mucosal surfaces. Although epidemiological data suggests oral HIV transmission is infrequent, HIV can be found in oral secretions. In a preliminary study of oropharyngeal HIV shedding, we examined 70 HIV+ men from Seattle and Peru, with a median CD4 count of 356 cells/mul; 52% were receiving highly active anti-retroviral therapy (HAART). Blood and oropharyngeal swabs were taken at weekly intervals and evaluated for HIV RNA. 20 men (29%) had detectable HIV RNA (vRNA) in lingual and/or pharyngeal swabs. Generalized estimating equations were used to show that each 1.0 log10 increase in plasma VL was associated with a 0.4 log10 increase in pharyngeal VL (P<0.001), and tonsillectomy was associated with a 0.6 log10 reduction in pharyngeal VL (P = 0.007), but HAART was not (P > 0.1). Infectious HIV was isolated from the posterior oropharynx in 5 (25%) of 20 vRNA+ men. Median mucosal VL was 6.35 log10 copies/ml in culture-positive men vs. 4.68 log10 copies/ml in culture-negative men (P = 0.06). HIV was not isolated from saliva, buccal or salivary mucosa. Biopsies of palatine and lingual tonsil (n=6) revealed vRNA and p24 antigen within lymphoid follicles, despite HAART-suppressed plasma VL. vRNA+ cells were in close proximity to and migrating within the tonsil capsule. HIV vRNA was present within tonsilar lymphocytes, macrophages (Mphi) and fewer dendritic cells (DC). Mucosal CCR5+ lymphocytes were the most prevalent vRNA+ 'dim' Mphi often harbored > 10-fold more vRNA and infectious virus. An examination of oropharyngeal viruses revealed greater env gene diversity than blood viruses examined simultaneously, particularly from men receiving HAART (P = 0.004). These studies demonstrate that the oropharyx is a site of HIV expression, where Mphi appear to play an important role in maintaining high titers of replicative HIV. Pre-existing oral pathology and sexual acts that facilitate contact with the lingual-pharyngeal mucosa may be associated with increased risk of viral transmission. This proposal is devoted to defining the pathogenesis of HIV infection in the oropharynx and will focus on determining anatomic site(s) and cells that support HIV replication and factors that influence the frequency and titer of virus at mucosal surfaces. It employs state-of-the-art methodologies and describes a combination of in vitro studies, using tonsil explants to investigate the dynamics of infection, and in vivo studies to assess HIV population dynamics that may be unique to the oral cavity, including 'compartmentalization' of drug-resistant virus.