乙型肝炎病毒表面抗原-乳酸/乙醇酸共聚物缓释微球的制备、释放和免疫学研究

目的:研究重组乙型肝炎病毒表面抗原(HBsAg)-乳酸/乙醇酸共聚物(PLGA)微球的制备工艺、聚合物降解、微球释放及小鼠皮下单剂量注射后的体内免疫应答水平.方法:采用正交设计,复乳法制备疫苗微球,测定PLGA及微球的理化性质和微球的体内免疫应答水平.结果:聚乙烯醇(PVA)浓度是影响微球粒径的的显著因素(P＜0.05);HBsAg释放主要靠微球中PLGA的溶蚀;将3种处方的微球混合单剂量免疫小鼠,抗体应答水平与现行的铝佐剂疫苗相当.结论:将不同释药行为的HBsAg-PLGA微球混合作为单剂量控释给药疫苗,具有很好的潜在优势.

Preparation,release and immunogenicity evaluation of HBsAg-PLGA microspheres

Objective: To investigate microencapsulation technique, release of HBsAg-PLGA microspheres and degradation of the polymer in vitro, and the level of immune response after the single-dose HBsAg-PLGA microspheres subcutaneously injected (sc) to BALB/c mice. Methods: HBsAg-PLGA microspheres were prepared by double emulsion microencapsulation technique with orthogonal experiments. The pharmaceutical characteristics of size and surface morphology, antigen loading efficiency, release of HBsAg-PLGA microspheres and degradation of the polymer in vitro, and the level of immune response after single sc of PLGA microspheres in BALB/c mice were investigated. Results: The concentration of PVA was the significant factor affecting the particle size (P<0.05). The release of protein from the microspheres was controlled mainly by the bulk erosion of polymer matrix. When single sc of HBsAg-PLGA microspheres mixed with different formulations, the immunogenicity effect was comparable to that of the aluminium adjuvant vaccine. Conclusion: The single-dose HBsAg-PLGA microspheres mixture with different release behavior is a promising candidate for controlled delivery vaccine.