Molecular Ontogeny of Oral Mucosal Resistance to SIV

流行病学研究表明，人类成年人的口腔对HIV感染具有相对的抵抗力，唾液中存在的一些可溶性因子被认为具有这种保护作用。相比之下，由感染艾滋病毒的母亲哺乳的婴儿的口腔感染相当常见，这表明在口腔对慢病毒的抵抗力方面存在年龄差异。我们将通过表征恒河猴口腔中的抗SIV先天免疫来研究这些年龄相关的抗病毒抵抗力差异的基础。这项拟议研究的长期目标是描绘防御素的抗艾滋病毒作用，防御素是目前已知存在于唾液中并在口腔上皮细胞中表达的抗病毒多肽。最近，三种人类防御素被确认为抗HIV因子，这些因子是由长期处于非进展期的HIV阳性患者的CD-8+T细胞产生的。我们假设防御素与唾液的抗SIV/HW特性和口腔粘膜的先天抵抗力有关，2)口腔防御素的表达是出生后形成的，3)局部应用一种或多种防御素可以增强新生儿对SIV的口腔抵抗力水平。为了验证这些假设，我们将追求以下具体目标： ？具体目标1是确定婴儿和成年恒河猴唾液中和/或口腔中表达的α、β和β-防御素的水平。 ？特异性目标2是合成和/或重组表达(在特异性目标1中)确认为成人唾液成分和/或在口腔组织中表达的特定α、β和theta-防御素。所生产的多肽将进行充分的表征和抗SIV效果的评估(特定目标3)，并将用于生产抗肽免疫试剂。 ？具体目的3是测定口服α、β和theta-防御素的体外抗SIV和抗HIV活性。使用和不使用新生儿和成人唾液进行抗HW检测，以确定这种天然液体对肽活性的影响。还将分析多肽的组合，以检测添加或协同的多肽-多肽相互作用。 ？具体目的4是确定外源性局部应用防御素是否可以改变新生儿恒河猴感染的易感性。

Epidemiologic studies demonstrate that the oral cavity of human adults is relatively resistant to HIV infection, and a number of soluble factors present in saliva have been postulated to confer this protection. In contrast, oral infection of infants who are breast fed by HIV-infected mothers is quite common, suggesting that there are age dependent differences in oral resistance to lentiviruses. We will investigate the basis of these age-dependent differences in antiviral resistance by characterizing anti-SIV innate immunity in the oral cavity of rhesus macaques. The long term goal of the proposed studies is to delineate the anti-HIV role of defensins, antiviral peptides now known to be present in saliva and expressed in epithelium of the oral cavity. Three human defensins were recently identified as anti-HIV factors produced by CD-8+ T cells from HIV-positive individuals who are long term non-progressors. We hypothesize that defensins conlribute to the anti-SIV/HW properties of saliva and to the innate resistance of oral mucosa, 2) that oral defensin expression develops postnatally, and 3) that the level of oral resistance to SIV in neonates may be augmented by topical application of one or more defensins. To test these hypotheses, we will pursue the following Specific Aims: ? Specific Aim 1 is to determine the level of alpha, beta,and theta-defensins present in saliva and/or expressed in the oral cavity of infant and adult rhesus macaques. ? Specific Aim 2 is to synthesize and/or recombinantly express specific alpha, beta, and theta-defensins confirmed (in Specific Aim 1) to be components of adult saliva and/or expressed in oral tissues. Peptides thus produced will be fully characterized and evaluated for their anti-SIV efficacy (Specific Aim 3), and will be used to produce anti-peptide immunologic reagents. ? Specific Aim 3 is to determine the anti-SIV and anti-HIV activities of oral alpha, beta,and theta-defensins in vitro. Anti-HW assays will be conducted with and without neonatal and adult saliva to ascertain the effect of this natural fluid on peptide activities. Combinations of peptides will also be analyzed to detect additive or synergistic pepfide-peptide interactions. ? Specific Aim 4 is to determine whether exogenous, topically administered defensin can alter the susceptibility to infection of neonatal rhesus macaques.