EBV Entry and Spread in the Oral Cavity

EBV 进入口腔并传播

• 批准号: 6912111
• 负责人: Lindsey M. Hutt-Fletcher
• 金额: $ 36.25万
• 依托单位: LOUISIANA STATE UNIV HSC SHREVEPORT
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-01-15 至 2008-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6912111
• 关键词: B cell receptor; Epstein Barr virus; binding proteins; blood chemistry; cell surface receptors; clinical research; complement receptor; epithelium; flow cytometry; glycoproteins; host organism interaction; human subject; integrins; intracellular transport; laboratory mouse; laboratory rabbit; oral pharyngeal; oral pharyngeal hyperplasia; oral pharyngeal neoplasm; polymerase chain reaction; southern blotting; virus infection mechanism; virus load; virus protein; virus replication; western blottings

DESCRIPTION (provided by applicant): EBV is a human gammaherpesvirus that is associated with both lymphoid and epithelial malignancies. The virus establishes persistent infections in almost all adults and the role that it plays in tumorigenesis is complex. Individuals who are immunosuppressed, particularly those infected with the human immunodeficiency virus (HIV), are at increased risk of developing EBV-associated malignancies. Part of this increased risk probably reflects a loss of control of replication of virus and an increase in virus load. The long term goal of this research is to understand how virus spreads and amplifies between and within hosts and to determine the roles that individual virus proteins play in the process. Five glycoproteins in the EBV envelope, gp350/220, gH, gL, gp42 and BMRF2, have been implicated as playing different roles in entry of B cells and epithelial cells. The immediate goals of this application are to evaluate the interactions of the glycoproteins with cell receptors and coreceptors and to determine their significance to virus infection. Aim one will examine the role that two part gHgL complexes and three part gHgl_gp42 complexes play in cell tropism and trafficking of virus between B cells and epithelial cells. Mutational analysis will be made of gH sequences to discriminate regions that are important to infection of epithelial cells but not B cells from regions that are important for entry into both. The stoichiometry of the gH complexes will be used to identify the origin of virus shed in the oropharynx, the identity of the gHgL receptor on epithelial cells will be sought and its potential role in transfer of virus from B cells to epithelial cells in close contact will be evaluated. Aim two will evaluate a role for the complement receptor type 2 (CR2) in post attachment events and in susceptibility of premalignant or malignant epithelial cells. Effects of deleting the cytoplasmic tail of CR2 on delivery of virus to the nucleus of the cell will be examined and the expression of CR2 on epithelial lesions ranging from mild dysplasia to invasive carcinoma will be determined. Aim three will determine the role that the RGD motif of the BMRF2 protein plays in infection of polarized epithelial cells. Recombinant viruses that lack BMRF2 or expresses a BMRF2 protein in which RGD sequences have been mutated will be made in the context of an EBV Bac and their phenotypes will be examined. Understanding how EBV targets cells that become malignant is important for development of ways to prevent the process.

描述（由申请方提供）：EBV是一种与淋巴和上皮恶性肿瘤相关的人γ疱疹病毒。该病毒在几乎所有成年人中造成持续感染，并且它在肿瘤发生中发挥的作用很复杂。免疫抑制的个体，特别是感染人类免疫缺陷病毒（HIV）的个体，发生EBV相关恶性肿瘤的风险增加。这种风险增加的部分原因可能是病毒复制失控和病毒载量增加。这项研究的长期目标是了解病毒如何在宿主之间和宿主内传播和扩增，并确定单个病毒蛋白在此过程中发挥的作用。EBV包膜中的5种糖蛋白gp 350/220、gH、gL、gp 42和BMRF 2在进入B细胞和上皮细胞中发挥不同的作用。本申请的直接目标是评估糖蛋白与细胞受体和辅助受体的相互作用，并确定其对病毒感染的意义。目的研究两部分gHgL复合物和三部分gHgl_gp42复合物在细胞嗜性和病毒在B细胞和上皮细胞之间运输中的作用。将对gH序列进行突变分析，以区分对上皮细胞感染重要但对B细胞感染不重要的区域和对进入两者都重要的区域。将使用gH复合物的化学计量来鉴定口咽中病毒脱落的来源，将寻找上皮细胞上gHgL受体的身份，并将评价其在病毒从B细胞转移至密切接触的上皮细胞中的潜在作用。目的二将评估补体受体2型（CR2）在附着后事件和癌前或恶性上皮细胞易感性中的作用。将检查删除CR2的胞质尾对病毒递送至细胞核的影响，并将测定CR2在从轻度异型增生到浸润性癌的上皮病变上的表达。目的三将确定BMRF 2蛋白的RGD基序在极化上皮细胞感染中的作用。将在EBV Bac的背景下制备缺乏BMRF 2或表达其中RGD序列已突变的BMRF 2蛋白的重组病毒，并检查其表型。了解EBV如何靶向恶性细胞对于开发预防该过程的方法非常重要。