Non-Tuberculous Mycobacteria (NTM) infections are frequent in the adult population with CF, causing sometimes severe lung disease, sometimes a much milder outcome. Therefore, it would be important to identify some biological markers, possibly from both the Mycobacterium and the CF patient’s immune response, in order to anticipate the outcome. Researchers will look for these markers by means of new “omics” techniques, in particular through the “single cell RNA sequencing”. RNA molecules are precursors in the synthesis of proteins – either coming from the mycobacterium or from the host – among which researchers expect to find the desired markers. The RNAs of the most common Mycobacterium abscessus complex (MA), will be studied; whereas in the host, white blood cell monocytes typically involved in the defensive response against NTMs will be studied. The ultimate goal is to improve the diagnosis of pulmonary complications in cystic fibrosis.