Received: 19 July 2018
Accepted: 13 February 2019
First Online: 26 February 2019
Ethics approval and consent to participate
: All animal experiments were performed in accordance with the German Animal License Regulations and were approved by the animal care committee of the Regierungspräsidium Freiburg (registration number: G-13/082).
: Not applicable.
: The authors declare that they have no competing interests.
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