KRT1 and pulmonary arterial hypertension: Transgenic mice expressing constitutively active form of AHR (AHR-CA) [35] (surmised to be equivalent to PAH-liganded AHR) have shown a gene profile with an increase in structural protein genes (KRT1, 6B, 16), protease genes (i.e., MMP), interleukins/chemokine genes (i.e., IL-1B, CXCL1, CCL8), Fc receptor genes (FCERIG), and antimicrobial peptide genes (i.e., DEFB) reproduced in our mouse models (PM group, OVA + PM group), which indicates the role of the PAH-liganded AHR in PM induced skin barrier dysfunction/immune deviation.