Acinetobacter baumannii is a gram-negative aerobic commensal coccobacillus that can cause severe healthcare-associated infections such as hospital-acquired bacterial pneumonia, especially amongst immunocompromised individuals. Its tolerance to desiccation and disinfectants contribute to its persistence in the hospital environment. Although its incidence is lower than for other healthcare-associated pathogens, A. baumannii infections are frequently multidrug resistant (MDR), making them difficult to treat and associated with high mortality. The World Health Organization has placed carbapenem-resistant A. baumannii on Priority 1 ‘‘critical’’ and the number 1 ranked organism recommended for new research and development. It has also been placed in the restrictive list of ESKAPE pathogens (3) and ranked as top priority by the American Centers for Disease Control and Prevention. Given the increasing difficulty in treating A. baumannii infections, there is an urgent need to develop new therapeutic strategies. Immunomodulators that stimulate selectively host innate immune mechanisms have potential as treatment. The risk of rapid development of resistance to innate immune effectors is low and the innate response promotes the development of an adaptive immune response that can protect over the long term. However, the innate response can also generate important pathologies such as cytokine storm. Thus, the development of such therapies requires a better characterized the protective host immune response controlling A. baumannii infection. Our group is working on several different aspects at the interface between the host and A. baumannii in experimental mouse models:
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The identification of immune effector mechanisms implicated in the control of A. baumannii growth in vivo
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The development of candidate vaccines capable of protecting immunocompromised mice against infection by A. baumannii.