Desai M P, Hilfinger J M, Amidon G L, Levy R J, Labhasetwar V
University of Michigan, Ann Arbor 48109, USA.
J Microencapsul. 2000 Mar-Apr;17(2):215-25. doi: 10.1080/026520400288454.
In this study, the adjuvant effect of the sustained release biodegradable nanospheres (100-150 nm in diameter) has been compared with alum. Nanospheres were formulated using a biodegradable polylactic polyglycolic acid copolymer (PLGA, 50:50) containing Staphylococcal Enterotoxin B (SEB) toxoid as a model vaccine antigen. Systemic immune response of the nanospheres containing toxoid was studied in rabbits by subcutaneous immunization. The data demonstrated that approximately 30% of the toxoid activity was lost following its encapsulation into nanospheres. Under in vitro conditions, nanospheres demonstrated sustained release of the toxoid. However, only 20% of the antigenic toxoid was released over the first 2 weeks of the release study. Immunization of animals with equal doses of toxoid, either using nanospheres or alum induced a comparable systemic immune response (IgG, IgM and IgA). The immune response reached a maximum level at 7 weeks post-immunization, which then gradually declined with time. The booster dose of toxoid at 19 weeks, either using alum or nanospheres induced similar immune response in both the groups, but was greater than the primary immune response. The studies, thus, suggest that biodegradable nanospheres could be used as a vaccine adjuvant.
在本研究中，已将直径为100 - 150纳米的可生物降解缓释纳米球的佐剂效应与明矾进行了比较。纳米球采用含有葡萄球菌肠毒素B（SEB）类毒素作为模型疫苗抗原的可生物降解聚乳酸 - 聚乙醇酸共聚物（PLGA，50:50）制备。通过皮下免疫在兔中研究了含类毒素纳米球的全身免疫反应。数据表明，类毒素包封到纳米球后约30%的类毒素活性丧失。在体外条件下，纳米球显示出类毒素的缓释。然而，在释放研究的前2周内仅释放了20%的抗原性类毒素。用纳米球或明矾以相等剂量的类毒素免疫动物诱导了相当的全身免疫反应（IgG、IgM和IgA）。免疫反应在免疫后7周达到最高水平，然后随时间逐渐下降。在19周时用明矾或纳米球给予类毒素加强剂量，两组均诱导了相似的免疫反应，但大于初次免疫反应。因此，这些研究表明可生物降解纳米球可用作疫苗佐剂。
