[A new pathophysiological element in severe asthma: GTPase Rac].

Asthma is a chronic airway condition defined by hyperresponsiveness, bronchial remodeling and chronic inflammation. A significant proportion of severe asthmatic patients remain uncontrolled despite recent therapeutic breakthroughs (biotherapies). Better understanding of the signaling pathways involved in the pathophysiological mechanisms underlying severe asthma could successfully address this unmet need. Rac GTPase acts as a molecular switch and has already been convincingly associated with airway hyperresponsiveness and bronchial remodeling in asthma. Having been elucidated by acquired knowledge regarding other pathologies. Its role in the inflammation mechanisms characterizing asthma is currently under specific evaluation.