Finger H, Heymer B, Wirsing von König C H, Emmerling P
Gerontology. 1982;28(4):223-32. doi: 10.1159/000212537.
Although the parenteral injection of dextran sulfate 500 (DS 500; 50 mg/kg body weight) into 22-month-old NMRI mice resulted in a complete loss of resistance when administered 1 day before the sublethal (4.5 X 10(3)) infection with Listeria monocytogenes, the consequences in aged animals were less dramatic than in young adult (2- to 3-month-old) controls. This was documented by prolonged survival times as well as reduced numbers of Listeriae in spleen. This indicates that aged mice possess an increased paghocytic capacity, as compared to young adult animals. In aged mice the DS 500-induced loss of resistance could be completely abolished by pretreatment with 3 X 10(9) heat-killed Bordetella pertussis organisms 4 days before the DS 500 injection, i.e., 5 days before listeric infection. This indicates that aged NMRI mice possess remarkable reserves in phagocytic activity.
虽然给22月龄的NMRI小鼠腹腔注射硫酸葡聚糖500（DS 500；50毫克/千克体重），在致死剂量（4.5×10³）单核细胞增多性李斯特菌感染前1天给药，会导致小鼠完全丧失抵抗力，但老龄动物的后果不如年轻成年（2至3月龄）对照动物严重。这通过延长存活时间以及脾脏中李斯特菌数量减少得到证明。这表明与年轻成年动物相比，老龄小鼠具有增强的吞噬能力。在老龄小鼠中，在注射DS 500前4天，即李斯特菌感染前5天，用3×10⁹热灭活的百日咳博德特氏菌预处理，可完全消除DS 500诱导的抵抗力丧失。这表明老龄NMRI小鼠在吞噬活性方面具有显著的储备能力。
