Nakaoka R, Tabata Y, Ikada Y
Research Center for Biomedical Engineering, Kyoto University, Japan.
Vaccine. 1996 Dec;14(17-18):1671-6. doi: 10.1016/s0264-410x(96)00098-9.
Ovalbumin (OVA)-containing poly(DL-lactic acid) (PDLLA) granules were prepared with different conditions. Following the intraperitoneal (i.p.) immunization of mice with the granules containing OVA, production of anti-OVA IgG antibody in the mouse serum was investigated. The i.p. injection of the granules induced a strong antibody production compared with that of free OVA, irrespective of the amount of OVA released for initial a few weeks and the period of OVA release. The serum level of IgG antibody induced by the granules was retained at a high level over 16 weeks although the period of OVA release and the amount of OVA released initially were different from each other. The initial OVA release for a few weeks was essential to induce the enhanced antibody production. Comparison of mice immunization by granules with different OVA loadings but at a similar dose revealed that antibody level was higher for the granules with lower loading than for those with the higher loading. However, when the granules were injected after encapsulation into a poly(vinyl alcohol) (PVA) hydrogel tube, the difference in their antibody level became insignificant. Because PVA encapsulation did not affect the OVA release profile, this finding indicates that the injection amount of the granules seems to have influenced the antibody production. We conclude that the release profile of OVA is not always a key factor to enhance the antibody production of OVA-containing granules so far as the initial OVA controlled release is achieved.
在不同条件下制备了含卵清蛋白（OVA）的聚（DL-乳酸）（PDLLA）颗粒。用含OVA的颗粒对小鼠进行腹腔内（i.p.）免疫后，研究了小鼠血清中抗OVA IgG抗体的产生情况。与游离OVA相比，颗粒的腹腔内注射诱导了强烈的抗体产生，无论最初几周OVA的释放量以及OVA的释放时间如何。尽管OVA的释放时间和最初的释放量彼此不同，但颗粒诱导的IgG抗体血清水平在16周内保持在较高水平。最初几周的OVA释放对于诱导增强的抗体产生至关重要。对不同OVA负载量但剂量相似的颗粒免疫小鼠的比较表明，负载量较低的颗粒的抗体水平高于负载量较高的颗粒。然而，当颗粒被包封到聚乙烯醇（PVA）水凝胶管中后再注射时，它们的抗体水平差异变得不显著。由于PVA包封不影响OVA的释放曲线，这一发现表明颗粒的注射量似乎影响了抗体产生。我们得出结论，就实现最初的OVA控释而言，OVA的释放曲线并不总是提高含OVA颗粒抗体产生的关键因素。
