Location and Ultrastructure of Borrelia japonica in Naturally Infected Ixodes ovatus and Small Mammals

• Published in: MICROBIOLOGY and IMMUNOLOGY Vol. 41; no. 1; pp. 13 - 19
• Main Authors: Yano, Yasuhiro, Takada, Nobuhiro, Ishiguro, Fubito
• Format: Journal Article
• Language: English
• Published: Tokyo Blackwell Publishing Ltd 01.01.1997; Center For Academic Publications Japan; Center for Academic Publications Japan
• Subjects: Animals; Animals, Wild - microbiology; Apodemus speciosus; Arvicolinae - microbiology; Bacteriology; Biological and medical sciences; Borrelia; Borrelia - isolation & purification; Borrelia - ultrastructure; Borrelia japonica; Crocidura; Ear - microbiology; Ear - pathology; Female; Fundamental and applied biological sciences. Psychology; Ixodes - microbiology; Ixodes - ultrastructure; Ixodes ovatus; Ixodidae; Male; Microbiology; Muridae - microbiology; Natural infection; Pathogenicity, virulence, toxins, bacteriocins, pyrogens, host-bacteria relations, miscellaneous strains; Shrews - microbiology; Small wild mammals; Parasitiformes; Spirochaetaceae; Spirochaetales; Rodentia; Host agent relation; Wild animal; Arachnida; Vertebrata; Mammalia; Acari; Ixodida; Ultrastructure; Arthropoda; Bacteria; Intermediate host; Invertebrata; Localization; Vector; Ixodidae; Borrelia japonica
• ISSN: 0385-5600; 1348-0421
• DOI: 10.1111/j.1348-0421.1997.tb01167.x

The internal organs of Ixodes ovatus and the ears of wild rodents (Apodemus speciosus, Eothenomys smithii) and an insectivore (Crocidura dsinezumi) were cultured to isolate borreliae; positive samples were examined for the distribution and dissemination of spirochetes in the host tissues using electron microscopy. Seven isolates were derived from the unfed ticks and the three species of mammals. These isolates were identified as Borrelia japonica judging from the outer surface protein profile using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and reactivity to a B. japonica-specific monoclonal antibody. Borreliae were found only in the midgut lumen of the tick in close contact with the microvilli on the midgut epithelium; on the other hand, borreliae found in the ears of the mammals existed freely in the collagenous intercellular substances of connective tissues or in close contact with fibrocytes. The ultrastructural disparities between the borreliae in ticks and mammals appeared to correspond to differences in motility. Interestingly, the borrelia which invaded through the perineurium appeared to contact the basement membrane of a Schwann cell that enclosed several nonmyelinated nerve fibers. This may offer important information regarding the involvement of the nervous system in Lyme disease.