Received: 28 August 2020
Accepted: 13 August 2021
First Online: 30 September 2021
: The research complies with the Swiss human research act (HRA) stating that small quantities of bodily substances removed in the course of transplantation may be anonymized for research purposes without consent (HRA chapter 5, paragraph 38).
: Not applicable.
: The authors declare that they have no conflict of interest.