Defining the Severe Paediatric Asthma Endotype

Patient Inclusion Criteria: * Minors aged 0 to 6 years or 6 to 12 years, hospitalized for assessment of Severe Asthma * Minors need with his follow-up an bronchial endoscopy with realization of LBA and biopsies of bronchial mucosa * Social insurance affiliation, except AME * Parents or legal guardians signed the Informed consent form Control Inclusion Criteria: * Minors aged 0 to 6 years or 6 to 12 years, hospitalized for assessment of severe respiratory syndrome except severe asthma * Minors need with his follow-up an bronchial endoscopy with realization of LBA and biopsies of bronchial mucosa * Social insurance affiliation, except AME * Parents or legal guardians signed the Informed consent form Patient Exclusion Criteria * Prematurity (\<37 weeks gestation) * Broncho-pulmonary dysplasia, immune deficits, non-Severe Asthma bronchopathies, cystic fibrosis, heart disease, ongoing biotherapy