Immunotherapeutic Potential of Modified Lipooligosaccharides and Lipid A's

描述（由申请人提供）：预防世界范围内已知的主要死亡原因传染性病原体，如流感、结核病和疟疾，以及引起鼠疫、土拉菌病和蝇蛆病的生物武器化病原体的潜在释放，需要产生体液和t细胞反应的疫苗。有效的组分疫苗需要添加佐剂以增加其免疫原性能力。直到最近，明矾盐是唯一被批准用于人类疫苗的佐剂，它需要反复使用，并且倾向于基于th2的T辅助免疫（体液）而不是TH1（细胞）。最近，类脂质A（单磷酰脂质A， MPL）佐剂已与明矾（AS04）联合用于两种fda批准的疫苗（Cervarix（人乳头瘤病毒）和Fendrix（乙型肝炎病毒））。此外，也通过toll样受体4 （TLR4）发出信号的合成脂质A模拟物氨基烷基氨基葡萄糖磷酸酯（AGPs）正在被研究作为佐剂或单独的免疫原性化合物。因此，TLR4激动剂在组份疫苗中作为佐剂有很大的应用前景。然而，已批准的TLR4激动剂MPL在效价和结构一致性方面存在明显缺陷，agp的合成成本高，劳动强度大。因此，这个修订后的R21应用程序的目标是

DESCRIPTION (provided by applicant): Protection from infectious agents known to be major causes of death worldwide, such as influenza, tuberculosis, and malaria, as well as potential release of bioweaponized agents which cause plague, tularemia, and meilloidosis require vaccines that generate humoral and T-cell responses. Effective component vaccines require the addition of adjuvants to increase their immunogenic capacities. Until recently alum salts, which require repeated applications and tend to be skewed towards T helper TH2-based immunity (humoral) rather than TH1, (cellular) were the only adjuvants approved for use in human vaccines. Recently, the lipid A mimetic (monophosphoryl lipid A, MPL) adjuvant has been combined with alum (AS04) in two FDA-approved vaccines (Cervarix (Human Papilloma Virus), and Fendrix (Hepatitis B Virus)). Additionally, synthetic lipid A mimetics aminoalkyl glucosaminide phosphates (AGPs) that also signal through Toll-Like Receptor 4 (TLR4) are being studied as both adjuvants or stand-alone immunogenic compounds. Thus, TLR4 agonists show great promise for use as adjuvants in component vaccines. However, the approved TLR4 agonist, MPL has distinct deficiencies both in potency and structural consistency and AGPs are labor intensive and costly to synthesize. Therefore, the goal of this revised R21 application is to undertake a novel approach of using Bacterial Enzymatic Combinatorial Chemistry (BECC) to make rationally-designed lipid A structures by modifying the lipid A structure of the lipooligosaccharide (LOS) from an attenuated (BSL-2 approved) Yersinia pestis (Yp) strain. This approach will use the non-stimulatory, hypoacylated, and bisphosphorylated lipid A structure present in LOS synthesized by this Yp strain as a scaffold to be modified by heterologous in trans expression of lipid A biosynthesis enzymes obtained from a wide variety of bacterial backgrounds with specificities for the removal or addition of fatty acid chain, phosphates moieties, and carbohydrates to the lipid A backbone, This process allow for the safe, cost effective, and efficient design of molecules with immunostimulatory potential. We will test the immunotherapeutic potential of these new molecules in vitro and in vivo to identify novel molecules representing adjuvants and/or immunomodulating reagents. We will also include well-characterized immunostimulants, such as MPL and known LPS structures as comparisons to the molecules synthesized by BECC. The successful demonstration of protective innate/adaptive immune responses by this novel approach of creating new adjuvants, in highly relevant in vivo animal model(s) could have important implications in the field of antigen recognition, formulation, and vaccine design.