en 25927023 <p>Background: Toll-like receptor (TLR)-mediated inflammatory processes are supposed to be involved in pathophysiology of spontaneous abortion and preterm labor. Here, we investigated functional responses of human endometrial stromal cells (ESCs) and whole endometrial cells (WECs) to lipopolysaccharide (LPS) and lipoteichoic acid (LTA).<br /> Methods: Endometrial tissues were obtained from 15 cycling women who underwent laparoscopic tubal ligation. Modulation of TLR2, TLR4 and MyD88 expression and pro-duction of pro-inflammatory cytokines by WECs and ESCs in response to LPS and LTA were assessed.<br /> Results: WECs and ESCs expressed significant levels of TLR4 and MyD88 transcripts but, unlike WECs, ESCs failed to express TLR2 gene. Regardless of positive results of Western blotting, ESCs did not express TLR4 at their surface as judged by flow cytometry. Immunofluorescent staining revealed intracellular localization of TLR4 with predominant perinuclear pattern. LPS stimulation marginally increased TLR4 gene ex-pression in both cell types, whereas such treatment significantly upregulated MyD88 gene expression after 8 hr (p&lt;0.05). At the protein level, however, LPS activation significantly increased TLR4 expression by ESCs (p&lt;0.05).&nbsp; LTA stimulation of WECs was accompanied with non-significant increase of TLR2 and MyD88 transcripts. LPS and LTA stimulation of WECs caused significant production of IL-6 and IL-8 in a dose-dependent manner (p&lt;0.05). Similarly, ESCs produced significant amounts of IL-6, IL-8 and also TNF-&alpha; in response to LPS activation (p&lt;0.05).<br /> Conclusion: Our results provided further evidence of initiation of inflammatory processes following endometrial TLR activation by bacterial components which could potentially be harmful to developing fetus.</p> Cytokine, Endometrium, Inflammation, LPS, LTA, Toll-like receptor 072 82 https://www.jri.ir/article/621 https://www.jri.ir/documents/fullpaper/en/621.pdf NesaRashidiImmunology Department, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran1399MahrooMirahmadianImmunology Department, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran1400MahmoodJeddi-TehraniMonoclonal Antibody Research Center, Avicenna Research Institute, ACECR, Tehran, Iranمحمود جدی‌تهرانی54SiminRezaniaBiophysics Institute, Medical University of Graz, Graz, Austria1401JamilehGhasemiNanobiotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iranجميلهقاسمي516SomaiehKazemnejadReproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran1402EbrahimMirzadeganReproductive Immunology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran1403SedighehVafaeiNanobiotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran1404MaryamKashanianDepartment of Obstetrics and Gynecology, Shahid Akbarabadi Hospital, Faculty of Medicine, Iran university of Medical Sciences, Tehran, Iranمريمكاشانيان636ZahraRasoulzadehDepartment of Immunology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran1479Amir HassanZarnaniImmunology Research Center, Iran University of Medical Sciences, Tehran, Iranامیرحسنزرنانیzarnani@avicenna.ac.ir, zarnania@gmail.com241