Tape stripping, which allows sampling of the epidermis to the midgranular layer, is a valid, minimally invasive way to identify cutaneous biomarkers in patients with hidradenitis suppurative (HS), results from a novel study showed.
"Tape strips can provide important clues to when and which drugs to use in HS in patients with both early and late disease, which can change clinical practice," corresponding study author Emma Guttman-Yassky, MD, PhD, professor and chair of dermatology at the Icahn School of Medicine at Mount Sinai in New York City, said in an interview. "It is noninvasive and nonscarring," she added.
Tape stripping has been validated in atopic dermatitis, psoriasis, and other dermatologic conditions in recent years. For the current study, which was published online in the Journal of the American Academy of Dermatology, and is believed to be the first of its kind, Dr. Guttman-Yassky and colleagues performed RNA sequencing from large D-Squame tape strips collected from lesional and nonlesional skin of 22 patients with HS and from 21 age- and sex-matched healthy controls. They correlated the expression of skin biomarkers between tape strips and a previously published gene-signature of HS biopsies. The mean age of patients with HS was 43 years, while the mean age of healthy controls was 35. The average International Hidradenitis Suppurativa Severity Score System (IHS4) score of the HS cohort was 36.
Consistent with published studies, the researchers found that tape strips identified an overall higher inflammatory burden in HS. Specifically, they observed an upregulation of known cytokines within the following pathways: Th1 (such as IFNG, CXCL9/10/11, and CCR5); Th17 (such as interleukin [IL]-17A/F, IL12B, IL23A, CAMP, and CCL20); Th2 (such as IL4R, IL13/IL31/IL10, CCR4, CCL7/CCL13/CCL24, TNFSF4/OX40L, and TNFRSF4/OX40); and Th22 (such as IL22 and IL32).
The researchers also found that the expression of Th17 and tumor necrosis factor (TNF)–alpha pathways were highly correlated between tape strips and biopsies and that HS clinical severity was significantly associated with expression of biomarkers, such as TNF-alpha, IL17A/F, OX40, JAK1-3, and IL4R in HS lesional and/or nonlesional skin.
"It was quite unexpected that we are able to identify, using a minimally invasive approach that samples only the upper layers of the epidermis, products and processes that are considered to be deeper-situated, such as IL-17, and other immune markers," Dr. Guttman-Yassky said in the interview. "We were also surprised to see how well the tape-stripped–derived skin molecular profile correlated with that of biopsies, as well as how well it correlated with the clinical disease severity of HS."
Also surprising, she added, was that the biomarkers in nonlesional tape-stripped skin, such as IL-17 and TNF alpha, "show high correlations with disease severity and provide clues to early disease."
If using tape strips in HS is validated in larger cohort studies, the potential cost implications of using this approach in practice remain unclear, Dr. Guttman-Yassky said. "It is currently not cheap, but we are hoping that one day, we can provide a means to diagnose the disease and treat it early, and appropriately, utilizing this approach," she commented. "We are excited about the applicability of this study to the early treatment and longitudinal follow up of HS with drugs that are targeting specific immune molecules and pathways," she said, adding that it will also be useful for helping determine which drug should be used for which patient.
She and her co-authors acknowledged certain limitations of the study, including its small sample size and the fact that tape stripping is limited to the epidermis.
Asked to comment on the study, Jennifer L. Hsiao, MD, a dermatologist who directs the HS clinic at the University of Southern California, Los Angeles, said the findings "have important potential implications for our ability to one day personalize treatments for a patient with early HS in a minimally invasive way."
As the study authors point out, she added, "tape strips only allow sampling of the epidermis, which is limiting in a disease like HS where much of the disruption is in the dermis with deep nodules and dermal tunnels. However, our overall goal should be to catch patients in the early stages of their disease before the occurrence of irreversible tissue damage such as dermal tunnels. Thus, the ongoing campaign for early diagnosis and early intervention by various stakeholders in the field of HS can help mitigate the impact of this inherent limitation of tape strips. It will be exciting to see larger studies that investigate tape strip results in relation to clinical phenotypes, disease progression, and therapeutic responses."
The study was funded by an International Dermatology Outcome Measures Hidradenitis Suppurativa Grant. Dr. Guttman-Yassky disclosed that she has been a consultant to, an adviser for, and has received research grants from many pharmaceutical companies. Of the remaining authors, 2 also had multiple disclosures and 11 had no disclosures. Dr. Hsiao disclosed that she is a member of the board of directors for the Hidradenitis Suppurativa Foundation. She has also served as a consultant for AbbVie, Aclaris, Boehringer Ingelheim, Incyte, Novartis, and UCB; as a speaker for AbbVie; and as an investigator for Amgen, Boehringer Ingelheim, and Incyte.
This article originally appeared on MDedge.com, part of the Medscape Professional Network.