Effects of 1,25(OH)2 vitamin D3 on cytokine production by endometrial cells of women with recurrent spontaneous abortion

Objective: To investigate immunomodulatory effect of 1,25(OH) 2 vitamin D3 (1,25(OH)2D3) on cytokine production by endometrial cells of women with unexplained recurrent spontaneous abortion (URSA). Design: In vitro study. Setting: Academic research center. Patient(s): Patients with URSA and healthy controls. Intervention(s): Treatment with 1,25(OH)2D3. Main Outcome Measure(s): Production of interferon gamma (IFN-gamma), interleukin-10 (IL-10), transforming growth factor beta (TGF-beta), IL-17, IL-6, and IL-8 by whole endometrial cells (WECs) and endometrial stromal cells in the presence and absence of 1,25(OH)2D3 and 1 alpha-hydroxylase activity of these cell populations were measured in patients with URSA and healthy controls. Result(s): 1,25(OH)2D3 interfered with production of cytokines by WECs of the control and URSA groups, except IL-8 which was increased in URSA group. In endometrial stromal cells, 1,25(OH)2D3 down-regulated cytokine production as well with stimulatory effect on the production of TGF-b in patients with URSA. Cytokine profile of WECs from patients with URSA skewed toward TH2 phenotype after treatment with 1,25(OH)2D3. Endometrial cells of both groups had comparable capacity to produce 1,25(OH)2D3. Conclusion(s): Considering the complex network of immunoregulation at the fetomaternal interface, potential beneficial effects of vitamin D3 in patients with URSA need to be investigated in clinical practice. Comparable levels of 1,25(OH)2D3 production and similar trend of cytokine expression by WECs of URSA and control groups after vitamin D3 treatment reflect the same local metabolic machinery of this hormone. (Fertil Steril (R) 2011;96:751-7. (C)2011 by American Society for Reproductive Medicine.)