The purpose of the proposed project is to characterize the neutrophile proteases which participate in the chronic inflammatory phenomenon associated with the cystic fibrosis and which are responsible for the degradation of the lung tissue.

The respiratory failure which results from it is one of main causes of the fatal evolution of this pathology but the anti-inflammatory therapies based on the use of antiproteases targeting specifically the soluble elastase did not end, until now, in the hoped results.

The identification of the other noxious targets is a crucial element to give new orientations to the anti-inflammatory strategies based on the administration of antiproteases which remain a promising way.

Inclusion Criteria:

• Man /woman older than 18 years (for adult and group)
• Child aged 6 to 18 years (for child group)
• Suffering from cystic fibrosis in stable condition, ie not having presented thrust acute attack of the broncho-pulmonary or hospitalization for treatment of his illness during the previous 2 weeks

Exclusion Criteria:

• colonized by Burkholderia cepacia ou Stenotrophomonas maltophilia
• non smoker (control group)
• Without history or respiratory respiratory disease known (control group)
• Antibiotic treatment and / or anti-inflammatory drug (NSAID or corticosteroids) in the 2 weeks prior to the inclusion in the study (control group)

Adults and children with cystic fibrosis