A new frontier in RNA biology emerged in the last decade with the identification of extracellular RNA as a way of communication widespread in all domains of life. Bacterial pathogens can use extracellular RNA to communicate intercellularly or with other species, exploiting this way to interact with their hosts, control them and establish infections. There is an increasing interest in understanding how organisms communicate with RNA and how pathogens exploit these mechanisms during infection. Extracellular vesicles (EVs) are one type of RNA carrier extremely important for RNA communication, transporting several types of RNA molecules between pathogens and hosts. Several noncoding regulatory RNAs, including small noncoding RNAs (sRNAs), are secreted in bacterial EVs that can deliver regulatory RNAs to host cells, modulating the host immune response to infection. Bacterial sRNAs are RNA transcripts that are not translated in proteins and can act by antisense base pairing with their targets. Commonly sRNAs have multiple targets, can regulate genes in cis and trans, modulate transcription and translation, and affect mRNA stability. Bacteria of the Burkholderia cepacia complex (Bcc), a group of opportunistic pathogens particularly feared among the cystic fibrosis (CF) community and implicated in several outbreaks among hospitalized non-CF patients, produce extracellular vesicles that induce cytotoxicity on the host cells and enhance pro-inflammatory responses. The main objectives of this project proposal are to produce and isolate Bcc EVs under clinically relevant conditions and analyze their RNA content to further evaluate its roles on host-pathogen interaction and in the unpredictable outcome of Bcc infections.