The search for blood biomarkers useful in treating atopic dermatitis patients.

Introduction: Atopic dermatitis (AD) is diagnosed based on clinical signs and symptoms as well as on a clinical course lacking distinct laboratory or histological features; however, the recent appearance of molecularly targeted drugs against AD urges us to try to discover and develop biomarkers useful for treating AD patients.

Areas Covered: This article commenced with a targeted PubMed search using 'atopic dermatitis' and 'biomarker' as keywords. We combined the findings from the B-PAD study that we have recently published and summarized data, particularly those recently published.

Expert Opinion: Many cells and molecules are listed as potential biomarkers of AD, most of which are type 2 mediators. Among them, CCL17/TARC is now thought to be the most reliable biomarker of AD. During the B-PAD study, we recently found that three biomarkers - squamous cell carcinoma antigen 2 (SCCA2), CCL26/eotaxin-3, and lactose dehydrogenase (LDH) - are better able than CCL17/TARC to assess the clinical severity and disease activity of AD. Moreover, although several biomarkers showed good ability to monitor the efficacy of molecularly targeted drugs against AD. More studies on the discovery and development of biomarkers of AD are awaited to refine treatments for AD patients.