Bay Y 3118, a new quinolone derivative, rapidly eradicates Listeria monocytogenes from infected mice and L929 cells.
Bay Y 3118 is a new quinolone derivative with pronounced activity against gram-positive bacteria including the facultatively intracellular bacterium Listeria monocytogenes. Bay Y 3118 was tested in vitro and in animal models of listeriosis. All strains of L. monocytogenes and other Listeria spp. were highly susceptible in vitro; the MICs for these organisms ranged from 0.062 to 0.25 micrograms/ml. Bay Y 3118 was rapidly bactericidal in vitro, with a postantibiotic effect occurring for 3 h after removal of the antibiotic. L. monocytogenes was eliminated from infected L929 cells treated with Bay Y 3118, suggesting a bactericidal effect on the listeriae in these cells. Immunocompetent mice were rapidly cured by treatment with 4 mg every 12 h. Concomitantly, the levels of interleukin 6 and gamma interferon in mouse sera declined rapidly. In immunocompetent mice, treatment with 2 mg of Bay Y 3118 every 12 h resulted in a greater initial reduction in the listerial counts in the organs than treatment with 2 mg of ampicillin every 12 h. Bay Y 3118 completely eliminated L. monocytogenes from the livers and spleens of chronically infected nude mice. However, some of the bacteria reappeared after the cessation of therapy. In conclusion, Bay Y 3118 is an excellent candidate substance for the therapy of infections caused by facultatively intracellular gram-positive bacteria such as L. monocytogenes.
Institute of Medical Microbiology and Hygiene, Faculty of Clinical Medicine, University of Heidelberg, Mannheim, Germany.
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T
Nichterlein
M
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Kretschmar
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C
Budeanu
J
J
Bauer
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W
Linss
H
H
Hof
D000667:Ampicillin / Q000627:therapeutic use; D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology*; D002460:Cell Line; D002908:Chronic Disease; D005260:Female; D024841:Fluoroquinolones; D007371:Interferon-gamma / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D008089:Listeria monocytogenes / Q000187:drug effects; D008088:Listeriosis / Q000188:drug therapy* / Q000378:metabolism / Q000382:microbiology; D008099:Liver / Q000382:microbiology; D051379:Mice; D008819:Mice, Nude; D008826:Microbial Sensitivity Tests; D008854:Microscopy, Electron; D015363:Quinolones / Q000627:therapeutic use*; D013154:Spleen / Q000382:microbiology
D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D015850:Interleukin-6; D015363:Quinolones; C079807:Bay Y3118; D000667:Ampicillin; D007371:Interferon-gamma