Rhinovirus (RV) species A and C play a fundamental role in the inception and exacerbations of asthma. However, the mechanisms underlying this relation are yet to be defined. This study identified T-cell epitopes in the RV viral protein that allowed for the in vitro characterisation of the adaptive immune-responses to RV-A and RV-C in a paediatric clinical cohort. Despite their biological differences, RV-A and RV-C stimulate similar !-cell responses in asthmatic and healthy children. Nonetheless, lower T-regulatory cell numbers found in asthmatics could explain their inability to control excessive immune responses to RV-infections, leading to airway hyper-responsiveness and asthma exacerbation.