Heat shock cognate protein 70 contributes to <it>Brucella </it>invasion into trophoblast giant cells that cause infectious abortion

• Main Authors: Furuoka Hidefumi, Tanaka Satoshi, Tachibana Masato, Watanabe Kenta, Horiuchi Motohiro, Suzuki Hiroshi, Watarai Masahisa
• Format: Article
• Language: English
• Published: BMC 2008-12-01
• Series: BMC Microbiology
• Online Access: http://www.biomedcentral.com/1471-2180/8/212

<p>Abstract</p> <p>Background</p> <p>The cell tropism of <it>Brucella abortus</it>, a causative agent of brucellosis and facultative intracellular pathogen, in the placenta is thought to be a key event of infectious abortion, although the molecular mechanism for this is largely unknown. There is a higher degree of bacterial colonization in the placenta than in other organs and many bacteria are detected in trophoblast giant (TG) cells in the placenta. In the present study, we investigated mechanism of <it>B. abortus </it>invasion into TG cells.</p> <p>Results</p> <p>We observed internalization and intracellular growth of <it>B. abortus </it>in cultured TG cells. A monoclonal antibody that inhibits bacterial internalization was isolated and this reacted with heat shock cognate protein 70 (Hsc70). Depletion and over expression of Hsc70 in TG cells inhibited and promoted bacterial internalization, respectively. IFN-γ receptor was expressed in TG cells and IFN-γ treatment enhanced the uptake of bacteria by TG cells. Administering the anti-Hsc70 antibody to pregnant mice served to prevent infectious abortion.</p> <p>Conclusion</p> <p><it>B. abortus </it>infection of TG cells in placenta is mediated by Hsc70, and that such infection leads to infectious abortion.</p>