The majority of asthmatic patients are well controlled by inhaled corticosteroid treatment, however some severe asthma resist this treatment. CCL18 is a target gene for corticosteroids and its dysfunction may correlate with phenotypes of asthma.

Inclusion Criteria:

1. control subjects =

   • non-atopic and non-smoking
   • cutting to negative pneumoallergens,
   • Total IgE levels less than 100 ku / L
   • no clinical history of asthma
   • without background treatment

2. patients with intermittent asthma =

   • being asymptomatic between asthma attacks,
   • with symptoms less than once a week
   • having a forced expiratory volume per second (FEV1) of at least 80% of the theoretical.
   • treated by ß2 mimetics on demand and will not have inhaled corticosteroids.

3. severe asthma insensitive to corticosteroid therapy =

   • continuous or nearly continuous treatment with oral corticosteroids (≥ 50% of the year) / or treatment with IC ≥ 1500 microg beclomethasone dipropionate equivalent (BDP)] airway obstruction fixed with FEV1 ranging from less than 15% after 7 days of oral corticosteroid therapy to 40 mg / day of prednisolone;
   • Followed at the immunoallergology pneumology consultation for at least 1 year will be recruited.

4. Severe corticosensitive asthma = continuous or near continuous treatment with oral corticosteroids (≥ 50% of the year) / or treatment with IC ≥ 1500 microg beclomethasone dipropionate equivalent (BDP)]

   • reversibility of FEV1 after treatment with oral corticosteroids.
   • Followed at the immunoallergology pneumology consultation for at least 1 year will be recruited.

5. controlled moderate asthma treated with inhaled corticosteroids <1500μg equivalent of beclomethasone dipropionate and with: ß2 long-acting mimetics (or anti-leukotriene, or theophylline) for at least 6 months.

Exclusion Criteria:

• existence of a chronic inflammatory pathology other than asthma
• active smoking
• pregnant or lactating women
• have received oral corticosteroid treatment in the previous 3 weeks,
• have received non-steroidal anti-inflammatory drugs (NSAIDs) in the previous 2 weeks.

patients consulting for either asthma or chronic rhinitis and meeting the criteria of the control group.