Growth Characteristics of Rickettsia Species LON Strains Closely Related to Rickettsia japonica Isolated from Haemaphysalis longicornis Ticks in Mouse-Derived L929 and Human-Derived THP-1 Host Cell Lines

被引：0

作者：

Tai, Hitoshi ^{[1
]}

Su, Hongru ^{[1
]}

Takamoto, Naoya ^{[1
]}

Fujita, Hiromi ^{[1
,2
]}

Takano, Ai ^{[3
]}

Oishi, Saori ^{[4
]}

Abe, Fuyuki ^{[4
]}

Ando, Shuji ^{[5
]}

Ohashi, Norio ^{[1
]}

机构：

[1] Univ Shizuoka, Grad Sch Integrated Pharmaceut & Nutr Sci, Grad Program Pharmaceut & Nutr Sci, Shizuoka, Japan

[2] Mahara Inst Med Acarol, Tokushima, Japan

[3] Yamaguchi Univ, Joint Fac Vet Med, Dept Vet Med, Yamaguchi, Japan

[4] Shizuoka Inst Environm & Hyg, Dept Microbiol, Shizuoka, Japan

[5] Natl Inst Infect Dis, Dept Virol 1, Tokyo, Japan

来源：

JAPANESE JOURNAL OF INFECTIOUS DISEASES | 2021年 / 74卷 / 02期

基金：

日本学术振兴会;

关键词：

CHICKEN-EMBRYO; DIVERSITY; CYCLE; IDENTIFICATION;

D O I：

10.7883/yoken.JJID.2020.444

中图分类号：

R51 [传染病];

学科分类号：

100401 ;

摘要：

Non-pathogenic Rickettsia species LON strains closely related to an agent of Japanese spotted fever (JSF), R. japonica, were isolated in Japan from Haemaphysalis longicornis ticks in 2001. However, the biological properties of LONs in mammalian host cells are poorly understood. In this study, microscopic analysis showed that LONs in a mouse-derived L929 host cell line were rod shaped with sizes of 0.3-0.5 x 0.5-2.0 mu m. Molecular analysis revealed the existence of a LON-specific disrupted open reading frame in R. japonica-related group-specific DNA regions. Growth kinetics of LON-2 and LON-13 strains analyzed by a quantitative real-time PCR showed 100-fold or more increment of LONs cultured in L929 host cells at 30 degrees C and slightly less increment at 33 degrees C, and 25-fold increment in human-derived THP-1 host cells at 35 degrees C on day 7 (168 h) post infection. The generation times of the two LON strains cultured in L929 and THP-1 were estimated to be 9.4-12.9 h and 9.6-10.9 h, respectively. To our knowledge, this is the first report on the biological characteristics of Rickettsia sp. LON strains in mammalian cells, which may provide significant information for the experimental approaches for other rickettsiae.

引用

页码：102 / 109

页数：8