Dupilumab in adults with moderate to severe atopic dermatitis Dupilumab is a fully human monoclonal antibody that blocks interleukin 4 and interleukin 13 in patients with asthma and cytokines of type 2 helper Th2 T lymphocytes in atopic dermatitis. In a randomized double blind placebo controlled trials involving adults who had moderate to severe atopic dermatitis despite treatment with topical glucocorticoids and calcineurin inhibitors patients treated with dupilumab had marked and rapid improvement in all the evaluated measures of atopic dermatitis disease activity. At 12 weeks patients in the dupilumab group had a greater reduction in the Eczema Area and Severity Index score body surface area affected and pruritus than patients in the placebo group.1 Flow cytometry helps differentiate severe atopic dermatitis vs DOCK8 deficiency DOCK8 or dedicator of cytokinesis 8 DOCK8 deficiency shares many clinical and laboratory features with severe atopic dermatitis. It is a primary immunodeficiency characterized by recurrent sinopulmonary infections dermatitis with cutaneous infections raised serum IgE levels eosinophilia and food allergy. Researchers have identified biomarkers routinely measured by flow cytometry on whole blood in clinical immunology laboratories that may differentiate DOCK8 deficiency from severe atopic dermatitis and identify those patients who benefit from further specialized diagnostic testing for DOCK8 deficiency.2 A new pruritus biomarker in seborrheic dermatitis Cathepsin S could be a potential marker of pruritus in D SD and could help assessing the effect of treatments. It has been hypothesized that mechanism leading to histamine release and pruritus could cathepsin S an activator of proteinase activated receptor 2 PAR2 . Recent research has found a significant increase in three biological markers cathepsin S PAR2 and histamine in patient with the dandruff seborrheic dermatitis versus healthy subjects and these markers were correlated with clinical parameters.3

References

1. Beck LA Tha i D Hamilton JD et al. Dupilumab treatment in adults with moderate to severe atopic dermatitis. N Engl J Med 2014 371 2 130 9.
2. Janssen E Tsitsikov E Al Herz W et al. Flow cytometry biomarkers distinguish DOCK8 deficiency from severe atopic dermatitis. Clin Immunol 2014 150 2 220 4.
3. Viod C Lejeune O Turlier V et al. Cathepsin S a new pruritus biomarker in clinical dandruff seborrhoeic dermatitis evaluation. Exp Dermatol 2014 23 4 274 5.