Translational Research - Université de Genève

Host Response
Klara Posfay-Barbe
Department of Pediatrics
Klara Posfay Barbe obtained her MD in 1994 at the University of Geneva. After intensive training
in pediatrics at the HUG, she followed from 2001 to 2004 a postdoctoral training in paediatric
infectious diseases and clinical research at the University of Pittsburgh Medical Center, USA.
In 2004 she returned to the Department of Paediatrics in Geneva where she was appointed
Cheffe de Clinique Scientifique in 2004 and Médecin Adjoint in 2009. In 2011, she obtained her
Privat-Docent. She is currently Head of the Department of Paediatric Infectious Diseases.
Immune responses to infection in children
Our group mostly studies antibody responses against well known antigens such as varicella or
Haemophilus influenzae in different settings (immunocompromised children, very young
infants), or against “new” bacteria (such as Parachlamydiae spp.). We are also interested in new
antigens present on Streptococcus pneumoniae, such as pneumococcal surface proteins (PcpA,
PhtD, PrtA, LytB), which elicit antibody responses after disease or carriage. These antigens,
which are conserved across all pneumococcal serotypes, could be used in the future to develop
new vaccines. Finally, we also study innate immunity by measuring the effect of pneumococcal
infection on the cellular expression of Toll-like receptors in children with recurrent lower
respiratory tract infections.
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54 Université de Genève • Faculté de médecine
Schäppi MG, Meier S, Bel M, Siegrist CA, Posfay-Barbe KM (2012), the H1N1 Study Group.
Protective Antibody Responses to Influenza A/H1N1/09 Vaccination in Children with Celiac
Disease. J Pediatr Gastroenterol Nutr. 54:817-819
L’Huillier AG, Wildhaber BE, Belli DC, Diana A, Rodriguez M, Siegrist CA, Posfay-Barbe KM (2012).
Successful serology-based intervention to increase protection against vaccine-preventable
diseases in liver-transplanted children: A 19-yr review of the Swiss national reference center.
Pediatr Transplant. 16:50-7
Hagerman A, Posfay-Barbe KM, Grillet S, Ochs MM, Brookes RH, Greenberg D, Givon-Lavi N,
Dagan R, Siegrist CA (2011). Failure to elicit seroresponses to pneumococcal surface proteins
18:756-62
Lienard J, Croxatto A, Aeby S, Jaton K, Posfay-Barbe K, Gervaix A, Greub G (2011). Development
of a new Chlamydiales-specific real-time PCR and its application to respiratory clinical
samples. J Clin Microbiol. 49:2637-42.
Posfay-Barbe KM, Kobela M, Sottas C, Grillet S, Taguebue J, Ekoe T, Lambert PH, Lecoultre C,
Siegrist CA (2010). Frequent failure of adolescent booster responses to tetanus toxoid
despite infant immunization: waning of infancy-induced immune memory? Vaccine
28:4356-61
Contact: Klara.PosfayBarbe@hcuge.ch
Host Response
Fold-increase of anti-pneumococcal surface protein (PSP) antibody concentrations
in bacteraemic children. The ratio of convalescent to acute anti-PSP antibody geometric
mean concentration (GMC) is illustrated for each PSP and age group. PcpA,
pneumococcal choline-binding protein A; PhtD, pneumococcal histidine triad D; PrtA,
serine proteinase precursor A. (Hagerman et al., 2011)
Université de Genève • Faculté de médecine
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