• Jean-Jacques Letesson's Research Group
  • Jean-Jacques Letesson's Research Group


Brucella virulence and immune response

Brucella spp. are characterized as stealthy pathogen that can persist lifelong in their hosts. Understanding the basis of this chronicity is  the “quest for the holy Graal” in brucellosis research. From the Brucella side, our group is involved in identifying the virulence factors that are linked to this persistence and how they are regulated (see also research topic 1).

From the host side, in collaboration with Eric Muraille from the ULB we are characterizing the innate and adaptive immune response of mice infected by Brucella melitensis. We started to phenotype, by using cytometry and immunohistology, the cells infected and/or recruited during the process of infection. The use of both KO mice and of selected Brucella mutants allow us to dissect the interplay between this bacteria and its host.

Brucella central metabolism and virulence adaptation

« Tell me what you eat and I will tell you what you are »

This is not only a proverbial sentence, but also the best way to start looking at the host bacteria interactions. Attenuated mutants are often metabolic mutants and crucial regulators of virulence genes expression also appears to regulate carbon and nitrogen metabolism.

Based on the knowledge we have on key global regulators of Brucella spp., on the availability of several Brucellagenomes and on a strong collaborative network, our group starts to characterize the the central metabolic network ofBrucella, the nature of its prefered carbon sources and how this network responds to genetic and environmental perturbations. The ultimate goal being the identification of the substrate(s) used by Brucella within their host.