Gupta R K, Chang A C, Griffin P, Rivera R, Siber G R
Chiron Vaccines, Emeryville, CA 94608, USA.
Vaccine. 1996 Oct;14(15):1412-6. doi: 10.1016/s0264-410x(96)00073-4.
Radiolabeled tetanus toxoid (TT) was prepared by detoxifying chromatographically purified tetanus toxin with 14C-labeled formaldehyde. 14C-TT was encapsulated inside poly (D,L-lactide-co-glycolide, 50/50) microspheres (MS) of varying average size (approximately 10 microns and approximately 50 microns). Balb/c mice were injected subcutaneously with 5 Lf (approximately 15 micrograms) of 14C-TT, encapsulated in MS, mixed with blank MS without encapsulated antigen, as soluble antigen or adsorbed onto aluminum phosphate (AlPO4) and radioactivity was monitored at the site of injection, draining lymph nodes, blood, liver, spleen, and kidneys at various intervals. At one day, approximately 95% and 90% radioactivity disappeared from site of injection for soluble TT or blank MS mixed TT and AlPO4 adsorbed TT, respectively, whereas approximately 55% and 70% radioactivity disappeared from site of injection for MS of average size approximately 50 microns and approximately 10 microns, respectively. By 7 days, 99% of radioactivity disappeared from site of injection for soluble TT or blank MS mixed TT, whereas 2-3% radioactivity persisted at the site of injection for AlPO4 adsorbed TT for 4 weeks. In contrast, approximately 20% radioactivity stayed at the site of injection for MS injected mice up to 4 weeks. At all time points, large MS (approximately 50 microns) showed more radioactivity at the site of injection than small MS (approximately 10 microns). Other organs showing radioactivity were draining lymph nodes and kidneys. Small MS with encapsulated TT showed highest level of radioactivity in lymph nodes at 4 h. In kidneys, soluble and AlPO4 adsorbed TT showed a peak of radioactivity at 4 h whereas TT encapsulated in MS showed a peak of radioactivity at 7 days. These results indicate that AlPO4 did not act as a depot for TT at the site of injection, but TT encapsulated in MS did form a depot for approximately 1 month.
用14C标记的甲醛对经色谱纯化的破伤风毒素进行解毒，制备放射性标记的破伤风类毒素（TT）。将14C-TT包封在平均尺寸不同（约10微米和约50微米）的聚（D，L-丙交酯-共-乙交酯，50/50）微球（MS）中。给Balb/c小鼠皮下注射5Lf（约15微克）包封在MS中的14C-TT，其与不含包封抗原的空白MS混合，作为可溶性抗原或吸附在磷酸铝（AlPO4）上，并在不同时间间隔监测注射部位、引流淋巴结、血液、肝脏、脾脏和肾脏的放射性。在第1天，可溶性TT或空白MS混合TT以及AlPO4吸附TT的注射部位分别约95%和90%的放射性消失，而平均尺寸约50微米和约10微米的MS注射部位分别约55%和70%的放射性消失。到第7天，可溶性TT或空白MS混合TT注射部位99%的放射性消失，而AlPO4吸附TT在注射部位4周内仍有2 - 3%的放射性残留。相比之下，MS注射小鼠的注射部位约20%的放射性可持续4周。在所有时间点，大MS（约50微米）在注射部位的放射性比小MS（约10微米）更多。显示有放射性的其他器官是引流淋巴结和肾脏。包封TT的小MS在4小时时在淋巴结中显示出最高水平的放射性。在肾脏中，可溶性和AlPO4吸附TT在4小时时显示放射性峰值，而包封在MS中的TT在7天时显示放射性峰值。这些结果表明，AlPO4在注射部位并非TT的储存库，但包封在MS中的TT确实形成了约1个月的储存库。
