Stein, H
Bob, R
Dürkop, H
Erck, C
Kämpfe, D
Kvasnicka, H-M
Martens, H
Roth, A
Streubel, A
Article History
Received: 22 April 2015
Revised: 11 June 2015
Accepted: 7 July 2015
First Online: 23 July 2015
Competing interests
: H Stein is shareholder and director of the Optistain GmbH. Optistain GmbH is the owner of the hybridoma cell line CAL2. All other authors have no conflict of interest.