S50 nanocapsules for transcutaneous DNA vaccination

描述（由申请人提供）：世界卫生组织估计，全世界有4000万人感染艾滋病，每天有16,000例新感染，为疫苗技术的新方法提供了持续的支持。DNA疫苗通过在有效转染后模拟细胞内病原体的感染而提供优于蛋白质疫苗的改善的细胞毒性T细胞（CTL）应答的优势。然而，新出现的证据表明，这种转染必须针对树突状细胞（DC），并与DC的显著成熟和迁移相结合。在开发AIDS疫苗的努力中，已经用DNA引发/病毒加强方案实现了与自然感染相竞争的早期CTL应答，但是这些应答在猕猴中没有足够的持续性以提供保护，这表明需要佐剂或重组病毒样颗粒来激发更强的初始T细胞应答。 我们已经开发了一种亚50 nm的纳米胶囊递送载体，能够小窝摄取，其通过使用离体猪皮肤器官培养模型的被动局部应用诱导大质粒有效转染到活化的迁移的朗格汉斯细胞中。LC（皮肤的树突状细胞）可有效诱导广泛的全身和粘膜反应，但通过当前的经皮方法，在大型动物中有效刺激迁移已被证明是困难的。由于与人类的解剖学相似性，猪模型对于经皮疫苗的评价具有上级优势。 在这项初步研究中，使用细菌蛋白13-半乳糖苷酶作为模型抗原，我们建议在器官培养物和断奶仔猪中制备和测试由透明质酸和铝或镍离子组成的疫苗制剂。减少给药改善细胞和体液免疫应答的证明将为恒河猴的后续研究提供坚实的基础，以改善粘膜免疫和T细胞对SIV的应答。

DESCRIPTION (provided by applicant): The WHO estimates that 40 million individuals are infected with AIDS worldwide and that 16,000 new infections occur daily, lending continuing support for new approaches in vaccine technology. DNA vaccines offer the advantage over protein vaccines of improved cytotoxic T cells (CTL) responses by simulating infection by intracellular pathogens following effective transfection. Emerging evidence suggests, however, this transfection must be directed at dendritic cells (DC) and be coupled with significant maturation and migration of DCs. In the effort to develop an AIDS vaccine, early CTL responses rivaling natural infection have been achieved with DNA prime / viral boost protocols, but these responses have not persisted sufficiently in macaques to provide protection, suggesting the need for adjuvants or recombinant virus-like particles to provoke stronger initial T-cell responses. We have developed a sub-50 nm nanocapsule delivery vector, capable of caveolar uptake, that induces efficient transfection of large plasmids into activated, migrating Langerhans cells by passive topical application using an ex vivo porcine skin organ culture model. LCs, the dendritic cells of skin, are efficient for inducing a broad range of systemic and mucosal responses, but effective stimulation of migration has proven difficult in large animals by current transcutaneous methods. Due to anatomical similarities with humans, the porcine model is superior for evaluation of transcutaneous vaccines. In this pilot study, using the bacterial protein 13-galactosidse as a model antigen, we propose to prepare and test in organ culture and in weanling pigs, vaccine formulations comprised of hyaluronan and aluminum or nickel ion. Demonstration of improved cellular and humoral immune responses with decreased dosing will provide a strong foundation for follow-on studies in Rhesus macaques to improve mucosal immunity and T-cell responses against SIV.