Vitamin D has immunomodulatory properties, which influence the immune system through a number of mechanisms, including the activation of dendritic cells (DCs). Langerhans cells (LCs) are dendritic cells in epidermis and belong to the skin immune system. DCs are professional antigen-presenting cells playing a major role in the induction of immune responses by activating native T-cells. In literature, there are no reports regarding the influence of vitamin D on DCs in patients with metabolic syndrome (MS). Thus, the aim of this study is to explore potential immunomodulatory activity of vitamin D on LCs in case of metabolic syndrome.In this study, we have conducted an analysis on a group of patients, both male and female, diagnosed with metabolic syndrome between the age of 40 and 55. Patients' clinical examinations, measurement of blood pressure, and waist circumference were conducted. Blood biochemical analyses (cholesterol, HDL, LDL, vitamin D level, etc.) were also determined. Full-thickness circular 4-mm Punch biopsies were taken from 49 patients. Specimens were stained with haematoxylin and eosin, as well as immunohistochemistry using a transmembrane CD1a Langerhans' cells marker was parformed by DakoCytomation EnVision method.The average age of patients is 43 years, and mean waist circumference is 95 cm. Total cholesterol is 5.5 mmol/l, LDL is 2.3 mmol/l, and average 25-hydroxyvitamin D is 27.0 ng/ml. In the skin conditioned with MS and low vitamin D level, evidence of perivascular accumulation of LCs in papillary dermis is observed, as well as a diffusion of mild interstitial cluster of LCs in some cases. In epidermis activity, the amount and filling of Birbeck's granules is changed in cases of 25-hydroxyvitamin D deficiency. In patients with low 25-hydroxyvitamin D level, an average LC quantity in one field of vision is higher in comparison to those who have normal amount of 25-hydroxyvitamin D. Therefore, it is necessary to further investigate vitamin D activity on LCs in cases of metabolic syndrome in order to determine interactions with lymphocytes, plasma cells, and mast cells as a part of the skin immune system. UDC Classification: 616-01, DOI: http://dx
