Photo by: Masur, via Wikimedia Commons
Researchers have identified a single gene biomarker that can differentiate atopic dermatitis (AD) from psoriasis with high accuracy using just a tape strip test, rather than biopsy.
In a press release issued on July 21, the investigators, from Mount Sinai in New York, explain how they identified the biomarker—nitride oxide synthase 2 (NOS2).
Tape strips were obtained from 20 adults with moderate to severe AD, 20 with moderate to severe psoriasis, and 20 healthy individuals. The investigators collected 20 strips from each subject, some from lesions and some from clinically unaffected skin. Skin cells collected from the strips were then molecularly profiled to identify any disease-related biomarkers.
The researchers also captured other genes related to immune and epidermal barrier function that were dysregulated in AD or psoriasis, and that distinguished the two conditions from one another. Tape strips from AD patients strongly expressed cell markers related to T-helper 2 (Th2) immune response, which is characteristic of AD, while psoriasis patients displayed much higher levels of Th1 and Th17 cytokines, which are characteristic of psoriasis.
From their evaluations they found that use of NOS2 as a biomarker could differentiate between AD and psoriasis with 100% accuracy.
The research was published online in the Journal of Allergy and Clinical Immunology.
Being able to differentiate between the two conditions without resorting to biopsies has several advantages, the researchers note.
“In the past, skin tissue biopsies have always been considered the gold standard for distinguishing between inflammatory skin diseases, but they can cause pain, scarring and increased risk of infection,” said the paper’s senior author Dr. Emma Guttman-Yassky. “This study shows that using adhesive tape strips may provide a minimally invasive alternative to skin biopsies for monitoring biomarkers of patients with these particular skin diseases and beyond.”
Dr. Guttman-Yassky is the Sol and Clara Kest Professor and Vice Chair of Dermatology at the Icahn School of Medicine at Mount Sinai.
She added that the molecular phenotypes described in the study were notably in accord with previous reports from skin biopsy studies and with the current mechanistic understanding of both diseases.
“This revolutionary study emphasizes the great need for better understanding immune and barrier alterations in both adults and children living with inflammatory skin disease,” said Dr. Mark Lebwohl, the Waldman Professor and Chair of Dermatology at the Icahn School of Medicine at Mount Sinai, in the release. He was not an author on the study.
“The results of this study may help provide a useful alternative to the invasive method of skin biopsies to track cutaneous disease activity in future clinical trials,” Dr. Lebwohl said.