粉尘螨(浸液)抗原PLGA微球的制备及其性质的研究

Study on preparation and properties of microspheres of dermatophagoides farinae antigen encapsulated by PLGA

目的 制备粉尘螨微球并对其性质进行研究。方法 制得粉尘螨抗原浸液,以聚乳酸-乙醇酸(PLGA75/25)为包裹材料,用双乳化溶剂蒸发法制备粉尘螨微球,光镜下测定直径、分布及跨距。用抽提法检测粉尘螨微球体外缓释速率,通过灌服过荧光微球(在粉尘螨抗原浸液中加入罗丹明B)不同时间的小鼠派氏集合淋巴结(Pey-er’s potches,PP)组织切片来测定其在小鼠体内的缓释作用。结果 粉尘螨微球的直径为(7.6±1.4)μm,跨距为0.54,符合正态分布,载药量为7.4％。体外释药呈双相特征,0～2天呈快速释放,4～32天为慢速释放相。小鼠灌服微球后,第1、15天都能在小鼠PP内找到微球。结论 此方法制备的粉尘螨微球达到缓释制剂的要求,可以用于对致敏小鼠的脱敏研究。

Objective To prepare microshpheres of the dermatophagoides farinae(Der. f) antigen and to study its properties in vitro and vivo. Methods After preparation of Der. f, and measurement of its concentration, an oil-in-oil emulsion-solvent extraction method was used to encapsulate the antigen in PLGA( 75/25) micro-spheres. The properties of microspheres including shape,diameter,diameter's distribution and span were assayed under microscope. The load of the Der. f antigen in microspheres was tested with Lowry mothed. Release kinetics in vitro of the drugs during the incubation at 37 C in double-distilled water was assayed with ELISA. One and fifteen days after mice were fed fluoro-microspheres(encapsulating Rhodamine B) ,the microspheres distribution in vivo was tested with slice of mice's Peyer' s patches(PP) under fluoromicroscopy. Results The microspheres were spherical and showed normal distribution. The diameter was (7.6 + 1.4) um,the span was 0.54, the load of the Der.f antigen was 7. 4%. Release of the microspheres in vitro was two phases; The first phase (0~ 2days) was a quick release phase and the second phase(4~32days) was a slow one. The microspheres encapsulating Rhodamine B were distributed to PP 1 day after mice were fed with the microspheres and also found in the PP 15 days later. Conclusion The prepared microspheres can be used for further study on desensitization to Der. f-sensitized mice.