title: [Protective effects of bacterial immunostimulants in mice infected by "Klebsiella pneumoniae" resistant to antibiotics after mutation or by plasmid transfer].
abstract: A streptomycin-resistant strain of K. pneumoniae obtained after mutation in vitro was found to be less virulent than the sensitive strain in mice. However, a single injection of lipopolysaccharides (LPS) administered 24 hours before challenge increased the host's resistance to both strains. In contrast, the virulence was not changed in K. pneumoniae accepting R-factors for ampicillin, streptomycin, chloramphenicol, tetracycline and sulphonamide. The plasmids were transferred to K. pneumoniae from two strains of Escherichia coli possessing different R-factors with the same resistance pattern. As in the first case, mice pretreated by endotoxin were protected against a challenge by microorganisms carrying R-factors. The capacity of the stimulated host to destory resistant or sensitive organisms was of the same order. Klebsiella recovered 5 or 24 hours after infection from the blood, liver and spleen did not lost their antibiotic-resistance. In this study, BCG and Corynebacterium granulosum were also used. Like LPS, these two immunostimulants protected very effectively mice infected with K. pneumoniae rendered resistant to antibiotics by R-factor transfer.
mesh_terms: D000667:Ampicillin / Q000494:pharmacology; D000818:Animals; D000942:Antigens, Bacterial / Q000008:administration & dosage*; D001500:BCG Vaccine / Q000008:administration & dosage; D002701:Chloramphenicol / Q000494:pharmacology; D003352:Corynebacterium / Q000276:immunology; D004731:Endotoxins / Q000008:administration & dosage; D005111:Extrachromosomal Inheritance / Q000187:drug effects*; D007275:Injections, Intravenous; D007710:Klebsiella Infections / Q000188:drug therapy; D007711:Klebsiella pneumoniae / Q000187:drug effects*; D008070:Lipopolysaccharides / Q000008:administration & dosage; D008297:Male; D051379:Mice; D009154:Mutation / Q000187:drug effects*; D010403:Penicillin Resistance / Q000187:drug effects*; D010957:Plasmids / Q000187:drug effects*; D011815:R Factors / Q000187:drug effects*; D013307:Streptomycin / Q000494:pharmacology; D013449:Sulfonamides / Q000494:pharmacology; D013752:Tetracycline / Q000494:pharmacology
chemical_list: D000942:Antigens, Bacterial; D001500:BCG Vaccine; D004731:Endotoxins; D008070:Lipopolysaccharides; D013449:Sulfonamides; D002701:Chloramphenicol; D000667:Ampicillin; D013752:Tetracycline; D013307:Streptomycin
vernacular_title: Immunostimulants bactériens et protection de la souris infectée par Klebsiella pneumoniae résistante aux antibiotiques par mutation ou par transfert de plasmides