Novel Carrier for Polysaccharide Conjugates and an EBV Vaccine

多糖缀合物和 EBV 疫苗的新型载体

基本信息

批准号：
7388052
负责人：
CLIFFORD M SNAPPER
金额：
$ 19.24万
依托单位：
HENRY M. JACKSON FDN FOR THE ADV MIL/MED
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-12-15 至 2009-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7388052
关键词：
Adjuvant Adjuvanticity Adolescent Affinity Anti-Bacterial Agents Antibodies Antibody-mediated protection Antigen Targeting Antigens Avidity B-Lymphocytes Bacteria Binding Biological Assay Burkitt Lymphoma CD4 Positive T Lymphocytes Carrier Proteins Clinical Trials Complement 3d Receptors Complement Receptor Conjugate Vaccines Dendritic Cells Diphtheria Toxoid Encapsulated Enzyme-Linked Immunosorbent Assay Epstein-Barr Virus Infections Follicular Dendritic Cells Goals Hodgkin Disease Human Human Herpesvirus 4 Immunization Immunocompromised Host Immunoglobulin G In Vitro Incidence Infant Infection Infectious Mononucleosis Ligands Link Macaca mulatta Measures Mediating Morbidity - disease rate Mus N-terminal Nasopharynx Carcinoma Non-Hodgkin&apos s Lymphoma Pathogenesis Plasma Polysaccharides Population Proteins Reaction Receptors, Antigen, B-Cell Recombinants Recruitment Activity Relative (related person)Research Design Risk Role Serotyping Structure of germinal center of lymph node Syndrome T-Lymphocyte Vaccines Vertebral column Viral Proteins aluminum sulfate anti-IgG bactericide base cell transformation env Gene Products extracellular immunogenic in vivo in vivo Model monocyte mortality neutralizing antibody nonhuman primate novel preclinical study prophylactic response virus envelope young adult

项目摘要

DESCRIPTION (provided by applicant): There currently exists a need for novel, immunogenic carrier proteins for new anti-bacterial polysaccharide (PS) conjugate vaccines, as well as a vaccine that is protective against Epstein-Barr virus (EBV) infection. The latter vaccine would have a potential global impact on the incidence of infectious mononucleosis, Hodgkin's and non- Hodgkin's lymphoma, nasopharyngeal carcinoma, and lymphoproliferative syndrome. The EBV protein, gp350, is the major target for EBV neutralizing antibody, as well as a ligand for CD21, a potent co-activator of the B cell antigen receptor. CD21 is also expressed by follicular dendritic cells where it mediates antigen trapping, important for induction of the germinal center reaction. Thus, gp350 in the form of a multimeric gp350-PS conjugate, has the potential to serve as both a potent carrier protein for PS-specific conjugate vaccines as well as an antibody-mediated vaccine for EBV. In preliminary studies we have: 1) expressed and purified a recombinant glycosylated N-terminal 72kDa fragment of the gp350 molecule, 2) conjugated multiple copies of gp350 to pneumococcal capsular polysaccharide, serotype 14 (PPS14) [PPS14-gp350], 3) demonstrated the ability of PPS14-gp350 to specifically bind to CD21 expressed on rhesus and human, but not murine, B cells, and 4) induced boosted plasma IgG anti-PPS14 and IgG anti-gp350 antibodies in young adult rhesus monkeys following i.m. immunization with as little as 0.05 mg of PPS14- gp350 adsorbed on alum. The goal of this proposal is to establish a proof-of-principle in non-human primates, for using gp350 clinically, as a combined novel carrier protein for PS conjugate vaccines and as a protective, antibody-based vaccine for EBV. In this proposal we will utilize young adult rhesus monkeys to: 1) directly compare the ability of alum-adsorbed unconjugated or PPS14-conjugated monomeric or unconjugated dimeric gp350 to elicit high titer and high affinity, EBV-neutralizing anti-gp350 antibody and gp350-specific T cell priming, and 2) directly compare the ability of diphtheria toxoid (DT) [an established carrier protein for conjugate vaccines], conjugated to PPS14, with PPS14- conjugated monomeric gp350 to elicit high titer and high affinity, protective anti-PPS14 antibody, and to determine the role of CD21 binding in the adjuvanticity of gp350 as a carrier protein for PPS14. These pre-clinical studies will form the basis for progressing directly to human clinical trials. Currently, there is no prophylactic vaccine for the Epstein-Barr virus (EBV), which is implicated in the pathogenesis of infectious mononucleosis, nasopharyngeal carcinoma, Burkitt lymphoma, non-Hodgkin's lymphoma, and lymphoproliferative syndrome in immunosuppressed patients. Further, there is also a need for novel protein carriers for polysaccharide conjugate vaccines, which elicit antibody-mediated protection against extracellular bacteria, due to the phenomenon of cross-inhibition. The proposed studies, using the rhesus macaque as an in vivo model, will determine the feasibility of using the EBV envelope protein, gp350, an intrinsically immunostimulatory molecule, as a combined novel carrier for polysaccharide-based conjugate vaccines and as a target antigen for a potent antibody-mediated prophylactic vaccine against EBV infection.

描述（由申请人提供）：目前需要用于新型抗菌多糖（PS）缀合物疫苗的新型免疫原性载体蛋白，以及针对 Epstein-Barr 病毒（EBV）感染的疫苗。后一种疫苗将对传染性单核细胞增多症、霍奇金和非霍奇金淋巴瘤、鼻咽癌和淋巴细胞增殖综合征的发病率产生潜在的全球影响。 EBV 蛋白 gp350 是 EBV 中和抗体的主要靶标，也是 CD21 的配体，CD21 是 B 细胞抗原受体的有效共激活剂。 CD21 也由滤泡树突细胞表达，在其中介导抗原捕获，这对于诱导生发中心反应很重要。因此，多聚体 gp350-PS 缀合物形式的 gp350 有潜力充当 PS 特异性缀合物疫苗的有效载体蛋白以及抗体介导的 EBV 疫苗。在初步研究中，我们：1) 表达并纯化了 gp350 分子的重组糖基化 N 端 72kDa 片段，2) 将多个拷贝的 gp350 与肺炎球菌荚膜多糖，血清型 14 (PPS14) [PPS14-gp350] 缀合，3) 证明PPS14-gp350 与恒河猴表达的 CD21 特异性结合的能力和人类（但不是鼠类）B 细胞和 4) 在肌肉注射后，在年轻成年恒河猴中诱导血浆 IgG 抗 PPS14 和 IgG 抗 gp350 抗体增强。用明矾上吸附的少至 0.05 mg 的 PPS14-gp350 进行免疫。该提案的目标是在非人类灵长类动物中建立原理验证，以在临床上使用 gp350 作为 PS 结合疫苗的组合新型载体蛋白以及作为 EBV 的保护性抗体疫苗。在本提案中，我们将利用年轻的成年恒河猴：1) 直接比较明矾吸附的未缀合或 PPS14 缀合的单体或未缀合二聚体 gp350 引发高滴度和高亲和力的 EBV 中和抗 gp350 抗体和 gp350- 的能力。特异性 T 细胞启动，2) 直接比较白喉类毒素 (DT) 的能力[一种已建立的缀合疫苗载体蛋白]，与PPS14缀合，用PPS14缀合的单体gp350引发高滴度、高亲和力的保护性抗PPS14抗体，并确定CD21结合在gp350作为载体的佐剂作用中的作用PPS14 的蛋白质。这些临床前研究将构成直接进行人体临床试验的基础。目前，还没有针对 Epstein-Barr 病毒 (EBV) 的预防性疫苗，该病毒与传染性单核细胞增多症、鼻咽癌、伯基特淋巴瘤、非霍奇金淋巴瘤和免疫抑制患者的淋巴增殖综合征的发病机制有关。此外，还需要用于多糖缀合物疫苗的新型蛋白质载体，其由于交叉抑制现象而引发针对细胞外细菌的抗体介导的保护。拟议的研究使用恒河猴作为体内模型，将确定使用 EBV 包膜蛋白 gp350（一种内在免疫刺激分子）作为基于多糖的结合疫苗的组合新型载体和作为疫苗的靶抗原的可行性。有效的抗体介导的针对 EBV 感染的预防性疫苗。