TSLP and asthma: Indeed, BECs from asthma patients are biased toward higher Thymic stromal lymphopoietin (TSLP) and lower IFNβ production.45 Commensal microbiota drive tonic IFNβ production by lung epithelial cells that protect host from respiratory viral infection.46,47 It is worth investigating if commensal microbiota can also protect host from asthma by driving lung IFNβ and enhancing steady-state lung mucosal tolerance.