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bioRxiv · 10.1101/2020.05.13.094037

Human dental pulp stem cells: a sanctuary for relapsing Bartonella quintana.

Oumarou Hama, H.·Hamada, A.·Aboudharam, G.·Ghigo, E.·Drancourt, M.
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Abstract

Bartonella quintana is a facultative intracellular bacterium responsible for relapsing fever, an example of non-sterilizing immunity. The cellular sanctuary of B. quintana in-between febrile relapses remains unknown but repeated detection of B. quintana in dental pulp specimens suggested long-term half-life dental pulp stem cells (DPSCs) as candidates. As the capacity of DPSCs to internalize microscopic particles was unknown, we confirmed that DPSCs internalized B. quintana bacteria: Gimenez staining and fluorescence microscopy localized B. quintana bacteria inside DPSCs and this internalization did not affect the cellular multiplication of DPSCs during a one-month follow-up despite the increase in the bacterial load. B. quintana-infected DPSCs did not produce Tumor Necrosis Factor- whereas an important production of Monocytes Chemoattractant Protein-1 was observed. These unprecedented observations suggested the possibility that DPSCs were shelters for the long-term persistence of B. quintana in the host, warranting further experimental and clinical investigations.

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Oumarou Hama, H., Hamada, A., Aboudharam, G., Ghigo, E., Drancourt, M.. 2020-05-13. Human dental pulp stem cells: a sanctuary for relapsing Bartonella quintana.. https://doi.org/10.1101/2020.05.13.094037

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