Upregulation of elafin expression in the fallopian tube of ectopic tubal pregnancies compared to the normal tubes

Background: Ectopic pregnancy is one of the most important causes of maternal deaths and fallopian tubes are the location of 95% of ectopic pregnancies. Elafin is a natural antimicrobial molecule that plays an important role as an anti-inflammatory agent in mucosal surfaces and has been found in the female reproductive tract. Objectives: The aim of this study was to investigate elafin expression, in the fallopian tube mucosa of ectopic pregnancies compared to the normal tubes using immunohistochemistry (IHC) techniques and quantitative re-verse transcription (qRT)-PCR. Methods: In this case-control study, uterine tube samples were obtained from patients with an indication for surgical removal of the tubes. The case group (n = 20) consisted of patients who were undergoing sal-pingectomy due to an ectopic pregnancy, the control group (n = 20) included patients who had a salpingectomy and hysterectomy. Using qRT-PCR and IHC, the expression of elafin was investigated in both study groups. Results: Immunohistochemical expression of elafin in the epithelium and connective tissue was significantly increased in the implantation site of the patients in comparison with the control group (P < 0.001). The level of elafin mRNA increased in the mucous membrane of the fallopian tube from patients with the ectopic pregnancy compared to the normal mucosa (P < 0.001). Conclusion: Increasing expression of elafin during an ectopic pregnancy may be a mechanism for enhancing innate immune response and be involved in related pathological conditions such as infection and ectopic im-plantation.