Study on the mechanisms of determination of the tropism and expression of the pathogenicity of Rickettsia

2015 Fiscal Year Final Research Report

• Project/Area Number: 25460534
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Bacteriology (including mycology)
• Research Institution: The University of Tokushima
• Principal Investigator: UCHIYAMA Tsuneo 徳島大学, 大学院医歯薬学研究部, 准教授 (90151901)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: リケッチア / トロピズム / 病原性 / 系統樹 / 紅斑熱群 / 疫学 / マダニ / 血管内皮細胞

Outline of Final Research Achievements

It is believed that tropism and pathogenicity of rickettsiae largely depend on their abilities of adherence to and growth in their host cells. Among the nine isolates from the ticks in the area where no spotted fever rickettsiosis occur, seven strains are very close to Rickettsia japonica genetically and possess highly cross-reactive antigenicity. Moreover, the abilities of adherence to and growth in the target endothelial cell primary culture are very low comparing to those of pathogenic rickettsiae including R. japonica.
These results are consistent with the fact that no spotted fever patients have been seen in the area but that more than ten percent of the habitat have antibody to R. japonica and propose a new paradigm to the epidemiology of spotted fever.

Free Research Field

細菌学