Abstract
BACKGROUND: Vitiligo is a common depigmenting skin disorder characterized by white macules and patches accompanied by local melanocyte loss, caused by autoimmune destruction. Vitiligo is classified into two major forms: segmental vitiligo (SV) and non-segmental vitiligo (NSV). It was also found that the IFN-ȣ/CXCL10 axis is functionally required for both progression and maintenance of the disease. Chemokine 10 (CXCL10) is a pro-inflammatory chemokine which was found to be elevated in the serum of vitiligo patients. UVB has been found to be a useful therapy that results in rapid repigmentation in NSV patients. OBJECTIVES: To evaluate CXCL10 in vitiligo patients before and after narrow band UVB (NB-UVB) phototherapy, which if targeted could provide new insights for therapeutic intervention for vitiligo. PATIENTS AND METHODS: The study included 25 active NSV patients who were able to comply with the study protocol in the Center of Excellence, Dermatology Outpatient Clinic, National Research Center, Egypt (February 2020-2021). All recruited patients were subjected to documentation of complete history. Dermatological assessment of vitiligo lesions, including vitiligo area score index (VASI) score, CXCL10 and extent of the disease were performed. A 3 mm punch biopsy from active vitiligo lesion (site of biopsy) was taken before and after treatment by NB-UVB, and then immunohistochemical staining was performed to evaluate expression of CXCL10. RESULTS: After treatment by NB-UVB there was a significant decrease in VASI score, extent of the disease and CXCL10 expression. CONCLUSION: The decrease in CXCL10 levels could be attributed to the effect of NB-UVB which leads to decrease in IFN-γ level, necessary to release CXCL10 through its pathway resulting in repigmentation and decrease in the extent of the disease and VASI scores.