Fedorocko P, Brezáni P, Macková N O
Department of Cellular and Molecular Biology, Faculty of Sciences, P. J. Safárik University, Kosice, Czech and Slovak Federative Republic.
Int J Radiat Biol. 1992 Apr;61(4):511-8. doi: 10.1080/09553009214551271.
Pretreatment of mice with 50-1000 micrograms of the bacterial extract Broncho-Vaxom (BV, free of endotoxin) before sublethal irradiation induced an increase in the number of endogenous haemopoietic stem cells (E-CFU). The degree of radioprotection was dependent on both the time of administration and the dose of BV. An optimal E-CFU survival was observed when 500 micrograms of BV was administered i.p. 24 h before irradiation. BV did not affect the day 9 CFU-S survival in the bone marrow directly after irradiation. However, 5, 9 and 12 days after irradiation, the number of day 9 CFU-S was almost 2-fold higher in the bone marrow of BV injected mice. Pretreatment with BV protected C57B1/6 mice in a dose-dependent manner from the lethal effect of ionizing radiation. A single dose (50, 100, 250, or 500 micrograms) of bacterial lysate injected i.p. 24 h before 9.5 Gy gamma-rays (LD100/21) protected 16%, 25%, 80%, and 94% of C57B1/6 mice, respectively. The dose reduction factor in the case when the BV (500 micrograms per mouse) was administered at that time was 1.18 (95% CL 1.12, 1.25).
在亚致死剂量照射前，用50 - 1000微克细菌提取物Broncho - Vaxom（BV，无内毒素）预处理小鼠，可使内源性造血干细胞（E - CFU）数量增加。辐射防护程度取决于给药时间和BV剂量。当在照射前24小时腹腔注射500微克BV时，观察到E - CFU的最佳存活情况。照射后立即观察发现，BV对骨髓中第9天的脾集落形成单位（CFU - S）存活没有直接影响。然而，照射后5天、9天和12天，注射BV小鼠骨髓中第9天CFU - S的数量几乎高出近2倍。用BV预处理以剂量依赖的方式保护C57B1/6小鼠免受电离辐射的致死效应。在9.5 Gyγ射线（LD100/21）照射前24小时腹腔注射单剂量（50、100、250或500微克）的细菌裂解物，分别保护了16%、25%、80%和94%的C57B1/6小鼠。在该时间点给予BV（每只小鼠500微克）时的剂量降低因子为1.18（95%置信区间1.12，1.25）。
