BIOADHESIVE MICROSPHERES FOR ORAL DNA VACCINATION

DNA疫苗是一个重要的新概念，它正在迅速被接受，成为使用传统纯化抗原和减毒病毒的一种可行和潜在的更好的替代方案。由于酶和粘膜的屏障，用于DNA疫苗应用的质粒的口服传递在很大程度上仍未被探索。尽管如此，通过Peyer‘s补片靶向肠道相关淋巴组织(GALT)的可能性为开发提供了一个令人信服的理由。Peyer’s Patch是诱导全身和粘膜免疫的重要部位。利用颗粒摄取的生物学现象，我们开发了一种热塑性、生物粘附性的“纳米”微球系统，能够在口服后将质粒DNA输送到Peyer‘s贴片中。这项提案的技术目标侧重于建立原理证明，即DNA微囊化为口服基因提供了一种途径，特别是在DNA疫苗应用中。HIV DNA疫苗原型将使用一种专利技术--相转化纳米封装(PIN)被封装到聚富马酸-二十二酸(FA：SA)微球中。将HIV DNA疫苗候选微球喂饲小鼠，用ELISA法测定免疫应答(血清免疫球蛋白、阴道/粪便免疫球蛋白A)。这一平台的开发满足了对将DNA输送到替代组织中的有效技术的需求，并提供了将DNA疫苗扩大到粘膜免疫至关重要的靶向疾病的机会。拟议的商业应用：口服途径是给药化合物的最简单途径。DNA疫苗口服递送系统的开发满足了对将DNA递送到粘膜组织部位的有效技术的需求。

DNA vaccination is an important new concept which is rapidly gaining acceptance as both a viable and potentially superior alternative to the use of traditional purified antigen and attenuated viruses. Due to enzymatic and mucosal barriers, oral delivery of plasmids for DNA vaccine applications has remained largely unexplored. Nonetheless, the possibility of targeting the gut associated lymphoid tissue (GALT) via the Peyer's patches, an important site for induction of both systemic and mucosal immunity, provides a compelling rationale for development. Utilizing the biological phenomenon of particle uptake, we have developed a thermoplastic, bioadhesive, 'nano-sized' microsphere system capable of delivering plasmid DNA into the Peyer's patches following oral administration. The technical objectives of this proposal focus on establishing proof of principle that microencapsulation of DNA provides a pathway for oral delivery of genes, specifically for DNA vaccine applications. A HIV DNA vaccine prototype will be encapsulated into poly fumaric-co-sebacic acid (FA:SA) microspheres using a proprietary technique, phase inversion nanoencapsulation (PIN). Microspheres encapsulating HIV DNA vaccine candiate will be fed to mice and resulting immune response (serum IgG, vaginal/fecal IgA) will be measured by ELISA. The development of this platform fulfills the need for an effective technique to deliver DNA into alternative tissues and provides the opportunity to expand DNA vaccination to target diseases where mucosal immunity is critical. PROPOSED COMMERCIAL APPLICATION: The oral route is the simplest route for administration of therapeutic compounds. The development of an oral delivery system for DNA vaccination fulfills the need for an effective technique to deliver DNA into mucosal tissue sites.