Respiratory failure resulting from chronic infection and inflammation of the airways still represent the primary cause of death for most individuals with cystic fibrosis (CF). Chronic bacterial infections are the main cause of lung damage with less known about the role of viral infections. As such, a better understanding of infection related pathology of the CF airways is needed. Bacteria remain the primary pathogens associated with airway inflammation, although additional important opportunistic pathogens are emerging. Besides a constitutive inflammatory state, CF typically has a course of exacerbations and remissions of pulmonary complaints, suggesting that external factors influence this course. In this regard, viral infections are often associated with worse respiratory symptoms in CF disease. Although it has been demonstrated that several members of the Polyomavirus (PyV) family infect the human respiratory tract and appear to be significant human pathogens in immunosuppressed people, remains unclear if these viruses may be important trigger of exacerbation in CF. Specifically, to date, the role played by Merkel cell Polyomavirus (MCPyV), in patients with a high risk of pulmonary morbidity such as CF patients, is poorly studied. In this regard, to improve our knowledge on the possible pathogenic involvement of MCPyV in CF, it will be proposed to study, in vivo, the MCPyV prevalence in CF patients and to analyze the simultaneous presence of MCPyV with respect to the bacterial colonization status in order to understand the impact of viral-bacterial co-infections in the CF airways. Moreover, since a much less information regarding the natural biology of MCPyV is, to date, available, it will be proposed to setting up an in vitro model primary bronchial/tracheal epithelial cells-based to understand if this cell types support MCPyV¿s growth, to study the MCPyV¿s life cycle and MCPyV¿s role in tumorigenesis.
