Gp340 and syndecan inhibition based microbicide for HIV

描述(由申请人提供)：在缺乏保护性疫苗的情况下，教育和抗艾滋病毒的杀微生物剂是控制全球艾滋病毒流行的最佳方法。我们的研究项目研究生殖道传播的最早事件。我们已经确定了一种由生殖道上皮细胞表达的蛋白质，它可能成为抑制艾滋病毒传播的潜在靶点，称为GP-340。我们已经证明，在体内、体外和体外，GP-340都表达在阴道和宫颈上皮细胞的细胞表面，并与HIV包膜结合。对生殖道传播具有重要意义的是，GP-340与病毒的结合导致病毒的传染性和半衰期增加。生殖道组织和细胞系表达的GP-340也介导了HIV的跨细胞作用，即大分子从细胞的一侧到另一侧的囊状运输。另一种名为Syndecan的分子已被研究并表明具有类似的跨感染和跨细胞特性，也在生殖道细胞中表达。在体外和体外生殖道传播模型中，我们已经确定了一种与GP-340结合的包膜多肽抑制剂，它可以阻断GP-340介导的跨感染和跨细胞感染。这种多肽包含一个基序的一部分，它也可以抑制Syndecan介导的感染，我们将对这种多肽进行修饰，以抑制与猕猴gp340和Syndecan的包膜结合，并将其开发为一种杀微生物剂。GP-340和Syndecan的这种潜在作用在分娩到生殖道管腔后但在与靶细胞相互作用和感染之前的感染阶段起作用，在杀微生物剂设计中非常有吸引力和新颖性。我们假设，干扰这一过程将抑制或阻断生殖道传播。在这项建议的最初R21部分，我们将建立猕猴生殖道传播的体外系统。如果我们证明猕猴gp340和Syndecan介导了跨感染和跨细胞反应，而V3环衍生多肽或改进版本阻断了猕猴gp340和syndecan介导的感染和跨细胞反应，我们将继续拨款的R33部分。这项研究的具体目的是：通过体外试验开发杀微生物剂，并在恒河猴阴道传播模型中测试阻断gp340和Syndecan-HIV Env相互作用对生殖道SIV传播的影响。通过这些具体目标，我们将开发一种新型杀微生物剂，并确定生殖道GP-340和Syndecan在HIV传播中的作用。如果成功，这些研究将提供一种基于宿主细胞与艾滋病毒相互作用的新杀微生物剂，促进生殖道传播到临床前试验研究。

DESCRIPTION (provided by applicant): Education and microbicides active against HIV represent the best approaches to controlling the epidemic worldwide in the absence of a protective vaccine. Our research program studies the earliest events in genital tract transmission. We have identified a protein expressed by genital tract epithelial cells that could serve as a potential target for inhibition of transmission of HIV called gp-340. We have demonstrated that gp-340 is expressed on the cell surface of vaginal and cervical epithelial cells, in vivo, in vitro, and ex vivo and binds HIV envelope. Of significance to genital tract transmission, gp-340 binding of virus leads to an increase in both the infectivity and half-life of the virus. Gp-340 expressed by genital tract tissue and cell lines also mediates transcytosis of HIV, the vesicular transport of macromolecules from one side of a cell to the other. A second molecule called syndecan has been studied and shown to have similar trans-infection and transcytosis properties and is also expressed by genital tract cells. We have identified a peptide inhibitor of envelope binding to gp-340 that blocks both gp-340 mediated trans-infection and transcytosis in in vitro and ex vivo models of genital tract transmission. This peptide contains a portion of a motif that inhibits syndecan mediated transinfection, as well, and we will modify this peptide to inhibit envelope binding to both macaque gp340 and syndecan and develop it into a microbicide. This potential role of gp-340 and syndecan to act at a stage of infection after delivery to the lumen of the genital tract but prior to interaction with and infection of target cells is very attractive and novel in microbicide design. We hypothesize that interfering with this process will inhibit or block genital tract transmission. In the initial R21 portion of this proposal, we will establish in vitro macaque systems of genital tract transmission. If we demonstrate that macaque gp340 and syndecan mediate trans- infection and transcytosis and V3 loop derived peptides or improved versions block macaque gp340 and syndecan mediated transinfection and transcytosis, we will proceed with the R33 portion of the grant. The specific aims of this are: microbicide development with in vitro testing and to test the effect of blocking gp340 and syndecan-HIV Env interaction on genital tract SIV transmission in the rhesus macaque vaginal transmission model. Through these specific aims, we will develop a new type of microbicide and determine the role of genital tract gp-340 and syndecan in HIV transmission. If successful, these studies will deliver a new microbicide based on host cell interactions with HIV that promote genital tract transmission to preclinical trial studies.