Translational Research - Université de Genève

Bacteriology
Christian van Delden
Department of Internal Medical Specialties
Department of Microbiology and Molecular Medicine
Christian van Delden obtained his Medical Degree in 1988 at the University of Geneva, then
FMH-certified qualifications in Internal Medicine in 1995 and in Infectious Diseases in 1999.
He held a three-year Postdoctoral Research Fellowship at the University of Rochester, New York
working on virulence regulation in Pseudomonas aeruginosa and returned to Geneva with a
Score A grant from the SNSF. Since 1998 he has led a research laboratory in the Department of
Microbiology and Molecular Medicine, and has been Head of the Immunocompromised Host
Programme at HUG since 2003. He is a co-founder and member of the Executive Office of the
Swiss Transplant Cohort Study and President of the Swiss Transplant Infectious Diseases
Working Group. He was appointed Associate Professor in 2011.
Role of Quorum-Sensing and Socio-Microbiological Behavior in the Pathogenesis of
Pseudomonas aeruginosa infections
Since 1998 we have studied resistance and virulence in P. aeruginosa. Our approach is
translational; we bring clinical hypothesis and strains into the laboratory, use genetics and
molecular microbiology for both “in patient” and “in vitro” studies, and try to implement our
findings at the bedside. With this approach we have characterised the development of
resistance on therapy and have identified novel virulence regulators. Recently we identified
Quorum-Sensing (QS) as a major risk factor for the progression from colonisation to infection
in intubated patients. We also investigated this progression from a socio-microbiological angle
with the development of QS-cheating and microbiological intra-species warfare based on
pyocin production. We further studied the efficacy of inhibiting QS to prevent infection in these
patients. Our clinical research activity involves infections in transplant recipients and their
prevention.
26 Université de Genève • Faculté de médecine
van Delden C, Köhler T, Brunner-Ferber F, Francois B, Carlet J and Pechère JC
(2012) Azithromycin to prevent Pseudomonas aeruginosa ventilator-associated-pneumonia
by inhibition of quorum-sensing: a randomized controlled trial. Intensive Care Med 38:1118-
1125.
Köhler T, Guanella R, Carlet J and van Delden C (2010) Quorum-sensing-dependent virulence
during Pseudomonas aeruginosa colonisation and pneumonia in mechanically ventilated
patients. Thorax 65:703-710.
Köhler T, Perron GG, Buckling A and van Delden C (2010) Quorum sensing inhibition selects for
virulence and cooperation in Pseudomonas aeruginosa PLos Pathogen 6;6:e1000883
Köhler T, Donner V and van Delden C (2010) Lipopolysaccharide as shield and receptor for Rpyocin
mediated killing in Pseudomonas aeruginosa. Journal of Bacteriology 192:1921-1928.
Köhler T, Buckling A and van Delden C (2009) Cooperation and virulence of clinical
Pseudomonas aeruginosa populations. Proc Natl Acad Sci USA 106:6339-6344
Contact: Christian.vanDelden@hcuge.ch
Bacteriology
Université de Genève • Faculté de médecine
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