Problem The purpose of the study was to investigate the different expressions of toll-like receptors (TLRs) in the proliferative and the secretory phase of endometrial tissue.
Method of study Eight infertile women were included in this study. The endometrial tissues of proliferative and secretory phase were obtained from each woman. The tissues were evaluated for the expression of mRNA for TLR1–10 by reverse transcribed polymerase chain reaction (RT-PCR). The proteins of TLR2, 3, 4, and 9 were evaluated by Western blot. The mRNA and protein level of proliferative and secretory endometrial tissue from the same woman was compared. The data were analysed with SPSS15.0.
Results TLR1–7, 9, and 10 mRNA were expressed throughout the menstrual cycle, but in the same woman, the expression of TLR2–6, 9, and 10 mRNA was higher during the secretory phase than that in the proliferative phase. The Western blot also showed that the protein expression of TLR2, 3, 4, and 9 was stronger in the secretory phase than that in the proliferative phase in the same woman.
Conclusion The expression of TLRs is cycle dependent in human endometrial tissue. The expressions of TLRs were higher in the secretory phase than that in the proliferative phase: this indicated that TLRs may be regulated by sex hormones throughout the menstrual cycle.