Smart John D, Nantwi Paul K K, Rogers David J, Green Keith L
Biomaterials and Drug Delivery Group, School of Pharmacy and Biomedical Sciences, University of Portsmouth, UK.
Eur J Pharm Biopharm. 2002 May;53(3):289-92. doi: 10.1016/s0939-6411(02)00012-7.
Previous work has identified lectins that bind to the cells present on the oral mucosa for their potential use as a means of retaining a drug delivery system on the mucosal surfaces of the mouth. In this study, a radiolabelling technique was developed to allow the quantification of lectin binding to human buccal cells in vitro, and the retention of the lectins in the oral cavity of a rat model in vivo. Lectins were labelled with 99mTc using a cyclic diethylene triamine pentaacetic acid conjugation technique. In the in vitro study, human buccal cells were obtained by scraping the inner surface of the cheek. The suspended cells were exposed to the labelled lectin solution for 30 min and after washing with buffer the activity associated with the cells determined. In the in vivo study, male Wistar rats were briefly anaesthetized during which 10 microl of a solution containing labelled lectin was applied into the buccal pouch. At set times the rats were killed and the lower buccal cavity mucosal tissue and tongue dissected out and monitored for bound lectin. The in vitro study indicated that the lectins from Arachis Hypogaea, Canavalia ensiformis and Triticum vulgaris bound to oral mucosal cells. The T. vulgaris lectin showed the greatest binding, calculated to be 6.77 x 10(9) molecules per cell. The in vivo retention of C. ensiformis and T. vulgaris lectins on rat oral mucosal tissue was also evident. The T. vulgaris lectin showed significantly higher levels of retained lectin after 30 min (29.54 +/- 4.20 microg SD) on the oral mucosal tissue and 28.37 microg (+/-2.13 SD) on the tongue and was still detected at similar levels after 2 h. These studies indicate that significant lectin binding to human buccal cells occurs in vitro and retention in an animal model occurs for over 2 h in vivo. The T. vulgaris lectin showed most promise for further work.
先前的研究已经鉴定出了一些凝集素，它们能够与口腔黏膜上的细胞结合，具有作为将药物递送系统保留在口腔黏膜表面的一种手段的潜在用途。在本研究中，开发了一种放射性标记技术，用于在体外定量凝集素与人类颊细胞的结合，以及在体内大鼠模型口腔中凝集素的保留情况。使用环状二乙烯三胺五乙酸偶联技术用99mTc标记凝集素。在体外研究中，通过刮擦脸颊内表面获取人类颊细胞。将悬浮细胞暴露于标记的凝集素溶液中30分钟，并用缓冲液洗涤后，测定与细胞相关的活性。在体内研究中，对雄性Wistar大鼠进行短暂麻醉，在此期间将10微升含有标记凝集素的溶液注入颊囊。在设定的时间处死大鼠，取出下颊腔黏膜组织和舌头，监测结合的凝集素。体外研究表明，来自花生、刀豆和小麦的凝集素与口腔黏膜细胞结合。小麦凝集素显示出最大的结合量，经计算为每个细胞6.77×10(9)个分子。刀豆凝集素和小麦凝集素在大鼠口腔黏膜组织上的体内保留也很明显。小麦凝集素在30分钟后在口腔黏膜组织上显示出显著更高水平的保留凝集素（29.54±4.20微克标准差），在舌头上为28.37微克（±2.13标准差），并且在2小时后仍以相似水平被检测到。这些研究表明，凝集素在体外与人类颊细胞有显著结合，在动物模型中在体内保留超过2小时。小麦凝集素显示出最有希望进行进一步研究。
