I worked for over ten years on various aspects of microbiology, but my main research interest has always been to understand how bacteria can cause diseases and how we could find a way to prevent them. I studied different bacterial species residing in human nasopharyngeal tract, each one with peculiar characteristics, but all capable to cause infections. Development of vaccines against bacterial pathogens can be considered as my main goal as a researcher and in the different projects that I carried out, I approached most of the different aspects of this research topic: from antigen selection and screening to the study of host immunity, from the characterization of bacterial virulence mechanisms to development of models of protection.