Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 0 0 2026 01 28 1 12 Omid Sadatpour Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Amirreza Azimi Department of Neurology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran AND MS Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran Zahra Salehi Cell Therapy and Hematopoietic Stem Cell Transplantation Research Center, Research Institute for Oncology, Hematology and Cell Therapy, Tehran University of Medical Sciences, Tehran, Iran AND Hematology, Oncology and Stem Cell Transplantation Research Center, Research Institute for Oncology, Hematology and Cell Therapy, Tehran University of Medical Sciences, Tehran, Iran Mohammad Javad Tavassolifar Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Ali Akbar Saboor-Yaraghi Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Maryam Izad Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran AND MS Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran 2025 08 31 2025 09 06 Chemokines and their receptors play a central role in mediating the migration of pathogenic T cells into the central nervous system of patients with multiple sclerosis (MS). Vitamin D and curcumin are known to possess anti-inflammatory and immunomodulatory properties; however, their combined effects on T-cell chemokine receptor expression in MS remain poorly defined. In this study, we investigated the in vitro effects of vitamin D, curcumin, and their combination on CD4+ and CD8+ T cells expressing CXCR3, CCR6, and CCR4 in patients with relapsing-remitting MS (RRMS). Peripheral blood mononuclear cells were collected from patients in relapse (n=10), remission (n=14), and healthy controls (n=15) and analyzed using flow cytometry. Relapse patients exhibited elevated frequencies of CXCR3+CD4+ T cells compared to healthy controls, which normalized following treatment. Increased CCR6+CD4+ T cells and CXCR3+CD8+ T cells were also observed in patients, with a significant reduction achieved only after combined treatment with vitamin D and curcumin. The combined treatment further decreased the mean fluorescence intensity of CXCR3 and CCR6 on T cells in relapse patients, while vitamin D alone specifically reduced CCR4+CCR6+CD4+ T cells, a TH17-like subset enriched during relapse. These findings indicate that vitamin D and curcumin, particularly in combination, modulate T-cell activity by downregulating chemokine receptor expression and may represent a promising adjunctive approach for controlling immune cell migration in MS. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/4568 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/4568/2289