TNF-α alters the inflammatory secretion profile of human first trimester placenta

Abstract

Implantation and subsequent placental development depend on a well-orchestrated interaction between fetal and maternal tissues, involving a fine balanced synergistic cross-talk of inflammatory and immune-modulating factors. Tumor necrosis factor (TNF)-α has been increasingly recognized as pivotal factor for successful pregnancy, although high maternal TNF-α levels are associated with a number of adverse pregnancy conditions including gestational hypertension and gestational diabetes mellitus. This study describes effects of exogenously applied TNF-α, mimicking increased maternal TNF-α levels, on the secretion profile of inflammation associated factors in human first trimester villous placenta. Conditioned culture media from first trimester villous placental explants were analyzed by inflammation antibody arrays and ELISA after 48 h culture in the presence or absence of TNF-α. Inflammation antibody arrays identified interleukin (IL)-6, IL-8, chemokine (C-C motif) ligand 2 (CCL2), CCL4, and granulocyte-macrophage colony-stimulating factor (GM-CSF) as the most abundantly secreted inflammation-associated factors under basal culture conditions. In the presence of TNF-α, secretion of GM-CSF, CCL5, and IL-10 increased, whereas IL-4 and macrophage CSF levels decreased compared with controls. ELISA analysis verified antibody arrays by showing significantly increased synthesis and release of GM-CSF and CCL5 by placental explants in response to TNF-α. Immunohistochemistry localized GM-CSF in the villous trophoblast compartment, whereas CCL5 was detected in maternal platelets adhering to perivillous fibrin deposits on the villous surface. mRNA-based in situ padlock probe approach localized GM-CSF and CCL5 transcripts in the villous trophoblast layer and the villous stroma. Results from this study suggest that the inflammatory secretion profile of human first trimester placenta shifts towards increased levels of GM-CSF, CCL5, and IL10 in response to elevated maternal TNF-α levels, whereas IL-6 and IL-8 remain unaffected. This shift may represent a protective mechanism by human first trimester villous placenta to sustain trophoblast function and dampen inflammatory processes in the intervillous space. Implantation and subsequent placenta development are mandatory steps for successful human pregnancy and depend on a well-orchestrated interaction between fetal and maternal tissues. Fetal-maternal interaction involves a fine balanced synergistic cross-talk of inflammaory and immune-modulating factors to allow maternal immune adaption and tolerance of the semiallogeneic fetus at the one hand, whereas maternal immune functions need to be maintained to fight off infections on the other hand. Various concepts and paradigms have been suggested trying to explain how the maternal immune system is modulated to guarantee a viable pregnancy. One of the proposed paradigms is based on studies by Wegmann et al, 1 describing a shift from an inflammatory T-helper 1 (Th1) cytokine profile to a rather anti-inflammatory T-helper 2 (Th2) profile. ...

Effects of maternal obesity on placental function and fetal development

“…It has recently been discovered that TNF-α stimulates production of a member of the VEGF family, placental growth factor (PlGF), in trophoblasts (Kato et al 2016). TNF-α is a key regulator of implantation and trophoblast function in the first trimester and has been shown to induce apoptosis in cultured trophoblast cells (Knöfler et al 2000; Pavlov et al 2016; Siwetz et al 2016). Thus, TNF-α appears to be important for trophoblast turnover and differentiation and overall placental development, a concept supported by the increasing maternal serum TNF-α levels across gestation (Christian and Porter 2014).…”

Repeated lipopolysaccharide exposure leads to placental endotoxin tolerance

“…Previous studies have demonstrated that TNF-α, IL-1β, ET-1, and MCP-1 are key players in the hierarchy of mediators that are involved in the cascade of infection-induced pre-term labor, 7,40-42 and IL-10 plays a central role in maintaining immune tolerance during pregnancy and countering inflammation associated with pre-term labor. [43][44][45] In addition, studies have demonstrated downregulation of TNF-α and IL-1β and upregulation of MCP-1 and IL-10 in the setting of endotoxin tolerance. 32,46…”

“…Levels of endothelin-1 (ET-role in maintaining immune tolerance during pregnancy and countering inflammation associated with pre-term labor [43][44][45]. Levels of endothelin-1 (ET-role in maintaining immune tolerance during pregnancy and countering inflammation associated with pre-term labor [43][44][45].…”

Visualization of tumor heterogeneity by in situ padlock probe technology in colorectal cancer

“…The sample was rehydrated by incubating the wells with PBS-T [DEPC-PBS with 0.05% Tween-20 (Sigma)] for 5 min at room temperature. In situ reactions were performed with slight modifications as previously described (Weibrecht et al 2013; Siwetz et al 2016). For reverse transcription, 1 µM of each LNA primer (Exiqon) was added in the wells with 5 U/µl TranscriptMe Reverse Transcriptase (DNA-Gdansk; Gdansk, Poland), 1 U/µl RiboLock RNase inhibitor (Thermo Fisher Scientific), 0.5 mM dNTPs (Thermo Fisher Scientific), and 0.2 µg/µl BSA (NEB; Ipswich, MA, USA) to the room temperature Reaction Buffer (DNA-Gdansk).…”