Clearance of Bacteria and Endotoxin in Conventional or Decontaminated Mice Undergoing Graft versus Host Disease or Radiation-Induced Injury
ARMED FORCES RADIOBIOLOGY RESEARCH INST BETHESDA MD
Pagination or Media Count:
Elimination of enteric microflora by antibiotic treatment removes a source of endogenous infection in animals whose resistance has been compromised, but it may reduce resistance against exogenous infection. This possibility was evaluated in conventional and decontaminated normal mice and in those exposed to 850 rads x radiation or undergoing graft versus host disease GVHD. When Salmonella typhimurium was perfused through mouse livers in situ approximately 70 percent of the organisms were trapped in hepatic sinusoids of normal and immunologically compromised animals. The trapping process was not affected by the absence of enteric flora. However, when bacteria were injected i.v. into mice, intestinal decontamination reduced bactericidal activity in normal and irradiated mice and in those undergoing GVHD. Approximately 50 percent of the injected S. typhimurium were killed in 20 min by conventional animals as opposed to the 25 percent killed by decontaminated animals. Reticuloendothelial uptake of 51Cr labeled bacterial endotoxin injected i.v. was reduced in animals receiving radiation or undergoing GVHD.
- Medicine and Medical Research