Cord blood TSLP, il-33, and IL-25 levels are associated with childhood atopic dermatitis

Atopic dermatitis is a chronic, itchy and inflammatory dermatosis that affects 20-25% of children and 2-3% of adults. Two main mechanisms are held responsible for pathogenesis. These mechanisms are defects in the structure and function of the skin with skin inflammation. Intrinsic deterioration of the epidermal barrier causes activation of chemokines that attract T cells, stimulation of natural immunity, Th2 polarization, and Langerhans cell activation (IL-25, IL-33 and TSLP) initiation and maintenance of inflammation. There is a biomarker which is Thymic Stromal Lymphopoietin is thought to play a role in the onset, development and progression of atopic diseases. It has been shown that IL-33 induces TSLP and sensitizes mast cells in the pathogenesis of atopic dermatitis. However, it can be also shown that TSLP and IL-33 together induce mast cell production of Th2 cytokines. Studies performed in humans have reported a higher level of IL-25 mRNA in the skin of patients with atopic dermatitis compared with healthy subjects. Researches about childhood allergic diseases resulted in that epithelial cell cytokines, TSLP and IL-33 contribute inflammation-related progress. However, atopic dermatitis is diagnosed by clinical findings. There is no definitive laboratory test to confirm the diagnosis. For this reason, researches continue with the aim of predicting the disease, taking necessary precautions and developing new treatments. In our study, we aimed to investigate the probability of using the TSLP, IL-33 and IL-25 levels as a biomarker in pregnancy and/or cord blood so that patients who are likely to develop AD can be diagnosed early and the control measures can be planned. Our study performed on pregnant women who were being followed by the outpatient clinic between October 2018-March 2019. Blood samples were driven just before the birth, from cord blood and 6-12 months of age. TSLP, IL-33, IL-25, and eosinophil levels were measured. And a survey contains 25 questions asked to pregnant women. Babies who have been taken their cord blood samples followed to check for AD diagnostic criteria between 6 months to 1-year-old. The criteria used for diagnosis were Hanifin-Rajka criteria. TSLP, IL-25, IL-33 levels were obtained significantly higher in AD improved babies' cord blood and their mothers. These results revealed, Trigger Levels Sensitivity for AD, as 58,33% and specificity is 100% for the TSLP>507,53 pg/ml in mother's and >600,87 pg/ml in cord blood. The sensitivity obtained for the level of mother serum IL-25>752,32 pg/mL is 83,33% and the specificity is 83,33%. The sensitivity for cord blood IL-25>686,09 pg/mL is 58,33% and specificity is 100,00%. As for the sensitivity for mother serum IL-33>16,24 pg/mL is 66,67% and for the specificity is 91,67% obtained. Our study proved that mothers whose babies developed AD, have significantly high TSLP, IL-25, IL-33 in their blood and also their cord blood TSLP and IL-25 levels are found significantly higher. Through this enlightenment, available biomarkers can be used but this subject should be supported by numerous studies.