CX3CL1 and asthma: A novel mechanism of CX3CL1 production has been discovered: rhinovirus 16 infection enhances the cleavage of the allergen protease from the apical epithelial surface to produce active CX3CL1, which may contribute to the synergistic effect of allergen exposure and rhinovirus infection in triggering asthma exacerbation and airway remodeling [181].