Evaluation of endometrial inflammation by quantification of macrophages, T lymphocytes, and interleukin-1 and -6 in human endometrium

Abstract

Purpose: Our purpose was to determine the impact of endometrial inflammation on fertility. Methods: The study population included 49 women: 5 women bearing an intrauterine device, 33 sterile patients, and 11 fertile women. Endometrial biopsies were performed between day 17 and day 21 of the cycle. Immunostaining was performed with an ABC kit. Monoclonal antibodies were CD68 for macrophages, CD3 for T lymphocytes, and B-E8 for interleukin (IL)-6; IL-1α and IL-1β were stained with polyclonal antibodies. A double immunofluorescence staining was performed to identify endometrial cells. Macrophage and lymphocyte rates were defined as the percentage of stained cells by field. Double staining was compared among macrophages, T lymphocytes, and anti-IL antibodies in each group. Results: The macrophage rate was high for women bearing an intrauterine device, intermediate for sterile patients, and low for fertile women (P = 0.03). There was a lack of double staining between activated T lymphocytes and anti-IL-6 antibody in tubal sterility and endometriosis. Endometrial macrophages were stained with anti-IL antibodies for all groups. Conclusions: Endometrial macrophages seem to be an interesting parameter for evaluating endometrial inflammation. In tubal infertility and endometriosis, the lack of expression of IL-6 in T lymphocytes could participate in impaired embryo implantation.