Witschi C, Mrsny R J
Department of Pharmaceutical Research and Development, Genentech Inc., South San Francisco, California, USA.
Pharm Res. 1999 Mar;16(3):382-90. doi: 10.1023/a:1018869601502.
Nasal delivery of protein therapeutics can be compromised by the brief residence time at this mucosal surface. Some bioadhesive polymers have been suggested to extend residence time and improve protein uptake across the nasal mucosa. We examined several potential polymer platforms for their in vitro protein release, relative bioadhesive properties and induction of cytokine release from respiratory epithelium.
Starch, alginate, chitosan or Carbopol microparticles, containing the test protein bovine serum albumin (BSA), were prepared by spray-drying and characterized by laser diffraction and scanning electron microscopy. An open-membrane system was used to determine protein release profiles and confluent, polarized Calu-3 cell sheets were used to evaluate relative bioadhesion, enhancement of protein transport and induction of cytokine release in vitro.
All spray-dried microparticles averaged 2-4 microm in diameter. Loaded BSA was not covalently aggregated or degraded. Starch and alginate microparticles released protein more rapidly but were less adhesive to polarized Calu-3 cells than chitosan and Carbopol microparticles. Protein transport across polarized Calu-3 cells was enhanced from Carbopol gels and chitosan microparticles. A mixture of chitosan microparticles with lysophosphatidylcholine increased protein transport further. Microparticles prepared from either chitosan or starch microparticles, applied apically, induced the basolateral release of IL-6 and IL-8 from polarized Calu-3 cells. Release of other cytokines, such as IL-1beta, TNF-alpha, GM-CSF and TGF-beta, were not affected by an apical exposure to polymer formulations.
We have described two systems for the in vitro assessment of potential nasal platforms for protein delivery. Based upon these assessments, Carbopol gels and chitosan microparticles provided the most desirable characteristics for protein therapeutic and protein antigen delivery, respectively, of the formulations examined.
蛋白质治疗药物经鼻腔给药时，其在鼻黏膜表面的停留时间较短，这可能会影响药物疗效。一些生物黏附性聚合物被认为可以延长药物停留时间，并提高蛋白质经鼻黏膜的吸收。我们研究了几种潜在的聚合物平台，考察它们在体外的蛋白质释放情况、相对生物黏附特性以及对呼吸道上皮细胞因子释放的诱导作用。
通过喷雾干燥法制备了含有测试蛋白牛血清白蛋白（BSA）的淀粉、海藻酸盐、壳聚糖或卡波姆微粒，并采用激光衍射和扫描电子显微镜对其进行表征。使用开放膜系统测定蛋白质释放曲线，并用汇合的极化Calu-3细胞单层评估相对生物黏附性、蛋白质转运增强情况以及体外细胞因子释放的诱导作用。
所有喷雾干燥微粒的平均直径为2 - 4微米。负载的BSA未发生共价聚集或降解。淀粉和海藻酸盐微粒释放蛋白质的速度更快，但与壳聚糖和卡波姆微粒相比，它们对极化Calu-3细胞的黏附性较差。卡波姆凝胶和壳聚糖微粒可增强蛋白质跨极化Calu-3细胞的转运。壳聚糖微粒与溶血磷脂酰胆碱的混合物可进一步提高蛋白质转运。从壳聚糖或淀粉微粒制备的微粒，经顶端应用后，可诱导极化Calu-3细胞从基底外侧释放IL-6和IL-8。顶端暴露于聚合物制剂对其他细胞因子如IL-1β、TNF-α、GM-CSF和TGF-β的释放没有影响。
我们描述了两种体外评估潜在鼻用蛋白质递送平台的系统。基于这些评估，在所研究的制剂中，卡波姆凝胶和壳聚糖微粒分别为蛋白质治疗药物和蛋白质抗原递送提供了最理想的特性。
