Increased CRHR1 expression on monocytes from patients with AA enables a pro‐inflammatory response to corticotrophin‐releasing hormone

Stress may play a key role in alopecia areata (AA), though the exact interactions of stress with AA remain undefined. Corticotropin-releasing hormone (CRH), the proximal regulator of the stress axis, has been recognized as an immunomodulatory factor in tissues and peripheral blood mononuclear cells (PBMCs). We used multicolour flow cytometry to identify receptor CRHR1 expression on PBMC subsets in AA patients (n = 54) and controls (n = 66). We found that CRHR1 was primarily expressed by circulating monocytes. CRHR1 expression on monocytes was enhanced in AA compared with controls (3.17% vs. 1.44%, p = 0.002, chi-squared test). AA incidence was correlated to elevated CD14