Protection Induced by Bacterial Endotoxin Against Whole-Body X-Irradiation in Germfree and Conventional Mice. ∗

Summary

When conventional and germ-free mice are administered 10 μg of E. coli endotoxin intraperitoneally 24 hours prior to whole-body X-irradiation, the LD.₅₀₍₃₀₎ X-ray dose is raised to about the same degree for both groups: from 739 r to 829 r for conventional mice and 834 r to 942 r for germ-free mice. For both groups the X-ray dose-reduction factors lie in the narrow range of 1.13 to 1.15.