Evaluation of Anti-endotoxin Vaccine for Human Use

描述（申请人提供）：革兰氏阴性菌感染可并发败血症、多器官衰竭和死亡。由于死亡率在过去十年中没有改变，因此需要新的策略来补充传统的抗生素治疗和支持性护理。我们研制了一种由e细胞Ol11:B4， Rc （JS）化学型解毒脂多糖（LPS）与B群脑膜炎球菌05 dLPS/OMP疫苗外膜蛋白络合而成的疫苗。该疫苗诱导对细菌LPS高度保守区域的抗体，在脓毒症动物模型中具有主动和被动的保护作用。在上次拨款期间，我们对24名人类受试者接种了这种疫苗。该疫苗安全且耐受性良好，但抗体反应低于兔和啮齿动物。因此，在本提案中，我们希望评估该疫苗与佐剂MF-59和寡核苷酸（CpG）一起使用时的安全性、免疫原性和功能活性，这两种佐剂均已安全用于人体。早些时候，我们发现疫苗诱导的抗体结合外源LPS，增强了大鼠循环中细菌和内毒素的清除，并中和了LPS诱导体外细胞因子和人类中性粒细胞形成超氧化物的能力。我们现在将把疫苗/佐剂免疫后的抗体水平与体内（清除研究和保护活性）和体外（LPS结合和LPS中和研究）的功能活性联系起来。这些活性可作为疫苗效力的替代标记（特异性目的1）。然后，我们将在人类受试者中进行疫苗和佐剂的I期研究（特异性目的II）。J5 LPS抑制疫苗诱导抗体与外源LPS的结合。因此，我们将通过比较35种LPS与其他核心LPS物种的完整和亚基结构的抑制活性来确定是否存在特异性的J5 LPS表位，并将与疫苗一起开发针对该表位的单克隆抗体（specific Aim III）。将明确补体、巨噬细胞和中性粒细胞在抗j5 dps抗体功能活性中的作用，以及免疫对动物和人细胞LPS表面受体（toll样受体4和CD14）的影响（Specific Aim IV）。如果成功，这些研究将导致预防和治疗败血症的II期和i期研究。

DESCRIPTION (provided by applicant): Infections caused by gram negative bacteria may be complicated by sepsis, multi-organ failure, and death. Since the mortality has not changed during the last decade, new strategies to supplement conventional antibiotic therapy and supportive care are required. We developed a vaccine composed of detoxified lipopolysaccharide (LPS) from E. cell Ol11:B4, Rc (JS) chemotype complexed to the outer membrane protein of group B meningococcus 05 dLPS/OMP vaccine). This vaccine induces antibodies to a highly conserved region of bacteria LPS that are protective both actively and passively in animal models of sepsis. In the last grant period we administered this vaccine to 24 human subjects. The vaccine was safe and well-tolerated, but the antibody response was lower than that measured in rabbits and rodents. Consequently, in this proposal we wish to evaluate the safety, immuno-genicity and functional activity of this vaccine when given with the adjuvants, MF-59 and oligonucleotide (CpG), each of which has been safely administered to humans. Earlier, we found that vaccine-induced antibody bound heterologous LPS, enhanced the clearance of bacteria and endotoxin from the circulation of rats and neutralized the ability of LPS to induce cytokines ex vivo and to prime superoxide formation by human neutrophils. We now will correlate antibody levels following vaccine/adjuvant immunization with functional activity in vivo (clearance studies and protective activity) and in vitro (LPS binding and LPS neutralization studies). These activities may serve as surrogate markers for vaccine efficacy (Specific Aim I). We then will do a phase I study of vaccine and adjuvants in human subjects (Specific Aim II). J5 LPS inhibits the binding of vaccine-induced antibody to heterologous LPS. We therefore will determine if there is a specific J5 LPS epitope by comparing the inhibitory activity of complete and subunit structures of 35 LPS with other core LPS species, and will develop monoclonal antibodies to this epitope with the vaccine (Specific Aim III). The role of complement, macrophages and neutrophils in the functional activity of anti-J5 dLPS antibodies will be defined as well as the effect of immunization on LPS surface receptors (toll-like receptor 4 and CD14) of cells from both animals and humans (Specific Aim IV). If successful, these studies will lead to phase II and Ill studies for the prevention and treatment of sepsis.