Smith S W, Billotte W G, Krane D, Sage K, Bajpai P K
Department of Biology, University of Dayton, Dayton, OH 45469, USA.
Biomed Sci Instrum. 1997;34:65-9.
Interleukin-2 (IL-2) is a potentially effective cytokine to be used for cancer treatment. Since keeping IL-2 doses at a low, continuous level is important to avoid side effects which accompany high IL-2 doses, a ceramic which release IL-2 could prove to be a beneficial method of drug delivery for cancer patients [1]. In vitro studies were performed to determine the optimal hydroxyapatite (HA) to IL-2 ratio for continuous release of IL-2 from HA using both a matrix and insert ceramic pellet. In the matrix pellet experiment, HA to IL-2 ratios of 25:1, 50:1 and 100:1 were tested by compressing a homogenous mixture of each variable in triplicate and placing each ceramic in 2.5 mL simulated body fluid (SBF) at 37 degrees C. The fluid was collected and replaced for each ceramic every two hours for 12 hours and at 24 hours. The collected fluid was then assayed for IL-2 content. Pellets consisting of 25:1 ceramic to drug ratio delivered almost the entire amount of IL-2 at the fastest rate. Composites of 100:1 IL-2 to HA delivered the least amount of IL-2 at the slowest rate. Release of IL-2 from the 50:1 ratio pellets was intermediate with respect to speed and amount of delivery. In the insert pellet experiment, similar laboratory procedures were used to show that 100:1 ratio insert pellets delivered IL-2 at a slower rate and in lesser amounts than 50:1 ratio insert pellets. Results of this study show that HA can deliver IL-2 at different rates by varying the ratio of HA to IL-2 in both matrix and insert ceramic pellets.
白细胞介素 -2（IL -2）是一种具有潜在疗效的细胞因子，可用于癌症治疗。由于将IL -2剂量维持在低水平且持续给药对于避免高剂量IL -2所伴随的副作用很重要，因此能够释放IL -2的陶瓷可能被证明是一种对癌症患者有益的药物递送方法[1]。进行了体外研究，以确定使用基质和插入式陶瓷微丸从羟基磷灰石（HA）中持续释放IL -2的最佳HA与IL -2比例。在基质微丸实验中，通过将每个变量的均匀混合物压制成三份来测试HA与IL -2比例为25:1、50:1和100:1的情况，并将每个陶瓷置于37摄氏度的2.5毫升模拟体液（SBF）中。每两小时收集并更换每个陶瓷周围的液体，持续12小时，并在24小时时进行收集。然后对收集的液体进行IL -2含量测定。陶瓷与药物比例为25:1的微丸以最快的速度释放了几乎全部的IL -2。IL -2与HA比例为100:1的复合材料以最慢的速度释放了最少的IL -2。50:1比例微丸的IL -2释放速度和释放量处于中间水平。在插入式微丸实验中，采用了类似的实验室程序来表明，100:1比例的插入式微丸释放IL -2的速度比50:1比例的插入式微丸慢，释放量也更少。本研究结果表明，通过改变基质和插入式陶瓷微丸中HA与IL -2的比例，HA可以不同的速率释放IL -2。
