Influence of estrogen therapy on immune markers in postmenopausal women

Objective: To evaluate the impact of estrogen therapy on cellular and humoral immune markers in postmenopausal women. Methods: This prospective, controlled cohort study included 30 patients who used oral estradiol (1 mg) for 14-17 weeks and 28 patients who served as controls. Total leukocytes and leukocyte sub-types were counted and immunophenotyped by flow cytometry. The concentrations of immunoglobulins and pro- and anti-inflammatory cytokines were also measured in the peripheral blood before and after estrogen therapy. Immunoglobulin E level was measured by electrochemiluminescence, and levels of immunoglobulins A, G, and M were measured by nephelometry. Simultaneous quantification of multiple cytokines was performed by chemiluminescence to measure the serum concentrations of interferon gamma, interleukin (IL)-4, IL-6, IL-10, and IL-17. Results: Hematological cellular components were not significantly different before and after the use of estradiol (p = 0.332-0.984). Serum concentrations of immunoglobulins G, M, E, and A also remained stable (p = 0.248-0.845). Finally, cytokines were not modified throughout the 14-17 weeks of follow-up (p = 0.407-0.873). Conclusion: Isolated estrogen therapy with 1 mg of estradiol for 14-17 weeks in postmenopausal women did not modify any of the cellular or humoral immune markers analyzed in this study.