TFRC and asthma: Severe and moderate asthma patients present low cell-free (non-heme) iron levels in BALF which correlate with lower lung function measured as (forced expiratory volume in 1 s (FEV1), whereas iron-loaded cells numbers are increased and also show increased expression of DMT1 and TFR1. These features were recapitulated by a murine model of house dust mite asthma where macrophages display the highest expression of Tfr1 and also upregulate Il13, suggesting that by accumulating iron they orchestrate the type 2 response in the lungs [260].