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Lager S, Gaccioli F, Ramirez VI, Jones HN, Jansson T, Powell TL. Oleic acid stimulates system A amino acid transport in primary human trophoblast cells mediated by toll-like receptor 4. J Lipid Res 2012; 54:725-733. [PMID: 23275648 DOI: 10.1194/jlr.m033050] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Obese women have an increased risk to deliver large babies. However, the mechanisms underlying fetal overgrowth in these pregnancies are not well understood. Obese pregnant women typically have elevated circulating lipid levels. We tested the hypothesis that fatty acids stimulate placental amino acid transport, mediated via toll-like receptor 4 (TLR4) and mammalian target of rapamycin (mTOR) signaling pathways. Circulating NEFA levels and placental TLR4 expression were assessed in women with varying prepregnancy body mass index (BMI). The effects of oleic acid on system A and system L amino acid transport, and on the activation of the mTOR (4EBP1, S6K1, rpS6), TLR4 (IĸB, JNK, p38 MAPK), and STAT3 signaling pathways were determined in cultured primary human trophoblast cells. Maternal circulating NEFAs (n = 33), but not placental TLR4 mRNA expression (n = 16), correlated positively with BMI (P < 0.05). Oleic acid increased trophoblast JNK and STAT3 phosphorylation (P < 0.05), whereas mTOR activity was unaffected. Furthermore, oleic acid doubled trophoblast system A activity (P < 0.05), without affecting system L activity. siRNA-mediated silencing of TLR4 expression prevented the stimulatory effect of oleic acid on system A activity. Our data suggest that maternal fatty acids can increase placental nutrient transport via TLR4, thereby potentially affecting fetal growth.
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Affiliation(s)
- Susanne Lager
- Center for Pregnancy and Newborn Research, Department of Obstetrics and Gynecology, University of Texas Health Science Center, San Antonio, TX; Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Francesca Gaccioli
- Center for Pregnancy and Newborn Research, Department of Obstetrics and Gynecology, University of Texas Health Science Center, San Antonio, TX
| | - Vanessa I Ramirez
- Center for Pregnancy and Newborn Research, Department of Obstetrics and Gynecology, University of Texas Health Science Center, San Antonio, TX
| | - Helen N Jones
- Center for Molecular Fetal Therapy, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Thomas Jansson
- Center for Pregnancy and Newborn Research, Department of Obstetrics and Gynecology, University of Texas Health Science Center, San Antonio, TX
| | - Theresa L Powell
- Center for Pregnancy and Newborn Research, Department of Obstetrics and Gynecology, University of Texas Health Science Center, San Antonio, TX
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Kim SK, Romero R, Savasan ZA, Xu Y, Dong Z, Lee DC, Yeo L, Hassan SS, Chaiworapongsa T. Endoglin in amniotic fluid as a risk factor for the subsequent development of bronchopulmonary dysplasia. Am J Reprod Immunol 2012; 69:105-23. [PMID: 23279628 DOI: 10.1111/aji.12046] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Accepted: 10/23/2012] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVE Cross-talk between inflammation and angiogenesis pathways has been recently reported. The objectives of this study were to: (i) examine whether amniotic fluid (AF) concentrations of soluble endoglin (sEng), a protein with anti-angiogenic properties, change during pregnancy, parturition, or intra-amniotic infection and/or inflammation (IAI); (ii) determine whether an increase in sEng in the AF of patients with preterm labor (PTL) and preterm prelabor rupture of membranes (PROM) is associated with adverse neonatal outcomes; and (iii) investigate potential sources of sEng in AF. STUDY DESIGN A cross-sectional study was conducted to include patients in the following groups: (i) mid-trimester (n = 20); (ii) PTL with term delivery (n = 95); (iii) PTL leading to preterm delivery with (n = 40) and without IAI (n = 46); (iv) preterm PROM with (n = 37) and without IAI (n = 37); (v) term in labor (n = 48) and not in labor (n = 44). AF concentrations of sEng were determined by enzyme-linked immunosorbent assay. Chorioamniotic membranes, umbilical cord blood, and AF macrophages were examined for the expression of endoglin. RESULTS (i) Patients with IAI had a higher median AF concentration of sEng than those without IAI (P = 0.02 for PTL and 0.06 for preterm PROM); (ii) AF concentrations of sEng in the 3rd and 4th quartiles were associated with IAI (OR 2.5 and 7.9, respectively); (iii) an AF sEng concentration ≥779.5 pg/mL was associated with bronchopulmonary dysplasia (BPD) (OR 7.9); (iv) endoglin was co-localized with CD14+ macrophages in AF pellets of patients with IAI by immunofluorescence and flow cytometry; and (v) the concentration of sEng in the supernatant was significantly increased after the treatment of macrophages with endotoxin or TNF-α. CONCLUSIONS Soluble endoglin participates in the host response against IAI. Activated macrophages may be a source of sEng concentrations in the AF of patients with IAI. An increase of sEng in the AF is associated with BPD and adverse neonatal outcomes.
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Affiliation(s)
- Sun K Kim
- Perinatology Research Branch, NICHD/NIH/DHHS, Bethesda, MD and Detroit, MI 48201, USA
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Wujcicka W, Wilczyński J, Nowakowska D. SNPs in toll-like receptor (TLR) genes as new genetic alterations associated with congenital toxoplasmosis? Eur J Clin Microbiol Infect Dis 2012; 32:503-11. [PMID: 23161283 PMCID: PMC3589654 DOI: 10.1007/s10096-012-1763-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Accepted: 10/08/2012] [Indexed: 12/29/2022]
Abstract
Nearly 40 % of pregnant women are infected with Toxoplasma gondii. Primary infections in pregnant women result, in approximately 30–50 % of patients, in transmission of T. gondii through the placenta to the fetus and then in congenital infections with severe, sometimes fatal course. Studies still do not provide sufficient data on the genetic bases of the immunity in fetuses, newborns, and infants with congenital toxoplasmosis. Previous research showed the contribution of toll-like receptors (TLRs) to non-specific immunity against T. gondii invasion, observed in T. gondii-infected animals, especially mice. So far, the activity of TLRs in defense against T. gondii infections was observed particularly for TLR2, TLR4, and TLR9 molecules. Differential TLR activity associates with both cell types, including a variety of placental cells and stage of pregnancy. Several single-nucleotide polymorphisms (SNPs) residing in three genes encoding these receptors were reported as significant genetic modifications of TLRs associated with different pregnancy disorders. Despite those data, genetic alterations of TLRs which have contributed to innate immune response against T. gondii infections are still not precisely described. In this article, we present reasons for the research of the plausible role of SNPs residing in TLR2, TLR4, and TLR9 genes in congenital toxoplasmosis development.
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Affiliation(s)
- W Wujcicka
- Department of Fetal-Maternal Medicine and Gynecology, Polish Mother's Memorial Hospital Research Institute, 281/289 Rzgowska Street, Lodz 93-338, Poland
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Zhang L, Yang H. Expression and localization of TLR4 and its negative regulator Tollip in the placenta of early-onset and late-onset preeclampsia. Hypertens Pregnancy 2012; 31:218-27. [PMID: 22582869 DOI: 10.3109/10641955.2011.642434] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVE Toll-like receptor 4 (TLR4) is a key component of the innate arm of the immune system that mediates inflammatory responses following exposure to bacterial lipopolysaccharides. In doing so, TLR4 may contribute to the pathogenesis of preeclampsia (PE). We sought to assess the spatio-temporal expression of TLR4 and its negative regulator Toll-interacting protein (Tollip) in placental tissues from normal and preeclamptic pregnancies. METHODS Using immunohistochemistry and immunoblotting, we investigated the localization of TLR4 and its negative regulator Tollip in first- and third-trimester human placenta. RESULTS TLR4 was found to be expressed in the cytoplasm of trophoblasts in both first- (n = 6) and third-trimester (n = 24) placental villous samples. Tollip was mainly located in the cytoplasm of cytotrophoblasts in the first-trimester placental tissues; in contrast, our analyses of third-trimester placental tissues demonstrated that Tollip was mainly located in the decidual cells. Using western blot analysis, TLR4 expression was shown to be significantly higher in early-onset PE tissues than control group placentas (n = 8 for each group, p < 0.01). However, we were unable to detect a significant difference between late-onset PE and normal controls (n = 8 for each group, p = 0.119). CONCLUSION These data demonstrate the novel observation that TLR4 may play a much more important role in early-onset PE. Interestingly, the spatial expression of Tollip at different stages of gestation may play an important role in the pathophysiology of PE.
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Affiliation(s)
- Li Zhang
- Department of Obstetrics and Gynecology, Peking University First Hospital, Beijing, PR China
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Boles JL, Ross MG, Beloosesky R, Desai M, Belkacemi L. Placental-mediated increased cytokine response to lipopolysaccharides: a potential mechanism for enhanced inflammation susceptibility of the preterm fetus. J Inflamm Res 2012; 5:67-75. [PMID: 22924006 PMCID: PMC3422858 DOI: 10.2147/jir.s32108] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Cerebral palsy is a nonprogressive motor impairment syndrome that has no effective cure. The etiology of most cases of cerebral palsy remains unknown; however, recent epidemiologic data have demonstrated an association between fetal neurologic injury and infection/inflammation. Maternal infection/inflammation may be associated with the induction of placental cytokines that could result in increased fetal proinflammatory cytokine exposure, and development of neonatal neurologic injury. Therefore, we sought to explore the mechanism by which maternal infection may produce a placental inflammatory response. We specifically examined rat placental cytokine production and activation of the Toll-like receptor 4 (TLR4) pathway in response to lipopolysaccharide exposure at preterm and near-term gestational ages. METHODS Preterm (e16) or near-term (e20) placental explants from pregnant rats were treated with 0, 1, or 10 μg/mL lipopolysaccharide. Explant integrity was assessed by lactate dehydrogenase assay. Interleukin-6 and tumor necrosis alpha levels were determined using enzyme-linked immunosorbent assay kits. TLR4 and phosphorylated nuclear factor kappa light chain enhancer of activated B cells (NFκB) protein expression levels were determined by Western blot analysis. RESULTS At both e16 and e20, lactate dehydrogenase levels were unchanged by treatment with lipopolysaccharide. After exposure to lipopolysaccharide, the release of interleukin-6 and tumor necrosis alpha from e16 placental explants increased by 4-fold and 8-9-fold, respectively (P < 0.05 versus vehicle). Conversely, interleukin-6 release from e20 explants was not significantly different compared with vehicle, and tumor necrosis alpha release was only 2-fold higher (P < 0.05 versus vehicle) following exposure to lipopolysaccharide. Phosphorylated NFκB protein expression was significantly increased in the nuclear fraction from placental explants exposed to lipopolysaccharide at both e16 and e20, although TLR4 protein expression was unaffected. CONCLUSION Lipopolysaccharide induces higher interleukin-6 and tumor necrosis alpha expression at e16 versus e20, suggesting that preterm placentas may have a greater placental cytokine response to lipopolysaccharide infection. Furthermore, increased phosphorylated NFκB indicates that placental cytokine induction may occur by activation of the TLR4 pathway.
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Affiliation(s)
- Julie L Boles
- Department of Obstetrics and Gynecology, Harbor-UCLA Medical Center, Los Angeles Biomedical Research Institute at Harbor-UCLA, David Geffen School of Medicine at UCLA, University of California, Los Angeles, Torrance, CA, USA
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Abstract
Preeclampsia (PE) manifested by hypertension and proteinuria complicates 3% to 8% of pregnancies and is a leading cause of fetal-maternal morbidity and mortality worldwide. It may lead to intrauterine growth restriction, preterm delivery, and long-term sequelae in women and fetuses, and consequently cause socioeconomic burden to the affected families and society as a whole. Balanced immune responses are required for the maintenance of successful pregnancy. Although not a focus of most studies, decidual cells, the major resident cell type at the fetal-maternal interface, have been shown to modulate the local immune balance by interacting with other cell types, such as bone marrow derived-immune cells, endothelial cells, and invading extravillous trophoblasts. Accumulating evidence suggests that an imbalanced innate immunity, facilitated by decidual cells, plays an important role in the pathogenesis of PE. Thus, this review will discuss the role of innate immunity and the potential contribution of decidual cells in the pathogenesis of PE.
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Affiliation(s)
- Chang-Ching Yeh
- Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, CT 06520-8063, USA
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Inflammatory bowel disease and pregnancy: overlapping pathways. Transl Res 2012; 160:65-83. [PMID: 22687963 DOI: 10.1016/j.trsl.2011.12.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2011] [Revised: 11/29/2011] [Accepted: 12/01/2011] [Indexed: 02/07/2023]
Abstract
Several studies have reported on the association between inflammatory bowel disease (IBD) and adverse pregnancy outcomes, such as preterm birth. The exact mechanisms of action are unclear; however, several pathways and processes are involved in both IBD and pregnancy that may help explain this. In this review, we discuss the immune system's T helper cells and human leukocyte antigens, inflammation, its function, and the role of Toll-like receptors (TLRs), NOD-like receptors (NLRs), and prostaglandins in the inflammatory response. For each of these topics, we consider their involvement in IBD and pregnancy, and we speculate as to how they can lead to preterm birth. Finally, we review briefly corticosteroids, biologic therapies, and immunosuppressants for the treatment of IBD, as well as their safety in use during pregnancy, with special focus on preterm birth.
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Berencsi G, Takács M. Barriers of the Human Organism and Their Achilles’ Heels. MATERNAL FETAL TRANSMISSION OF HUMAN VIRUSES AND THEIR INFLUENCE ON TUMORIGENESIS 2012. [PMCID: PMC7121758 DOI: 10.1007/978-94-007-4216-1_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The human body is covered by barriers separating it from the external and internal surroundings. The “milieu enterieur” has to be stabilised in spite of the variable external and internal conditions of toxic, osmotic, microbial and climatic environmental circumstances. This first line of barriers is composed of skin and mucous membranes of complicated structures. A second line of barrier system is present in our organisms. Certain organs have to be separated from the immune system and other parts of the body because of evolutionary reasons (eye-bulb and testicles) because of unique proteins “unknown” for the acquired immune system. The blood-brain barrier (BBB) is providing enhanced safety circumstances for the central nervous system. The second line of barriers is represented by the special properties of the capillary endothelial system. The maternal-fetal barrier is the most complex. At the maternal fetal interface two individuals of two different haplotypes has to be live 9 months separated by a very complicated dynamic barrier. The placenta is the organ, which is separating the maternal and fetal tissues. Similar to others the bidirectional transport of gasses, metabolites, cells, proteins, regulatory substances, are transported by active or passive transcellular and intercellular mechanisms. The fetal immune system develops immunotolerance to all maternal cells and antigens transferred transplacentally. The problem is to mitigate the maternal immune system to tolerate the paternal haplotype of the fetus. In the case of normal pregnancy a complex series of physiological modifications can solve the problem without harmful consequences to the mother and fetus. The outermost contact cells of trophoblasts express instead of HLA-class Ia and class II antigens non-variable HLA-C, HLA-E, HLA-F and HLA-G antigens. The first consequence of this is reduction of the activity of maternal natural killer cells and maternal dendritic cells; Progesteron, micro-RNA and mediators influence the development of T effector-cells. The production of soluble HLA-G(5 and 6) and IL-10 supports the differentiation of Th-2 CD4+ helper cells, reducing the ability of maternal cells to kill fetal cells. Series of receptors and costimulators are expressed by the different lines of semi-allogenic trophoblast cells to bind HLA-G and mitigate maternal immune response; The maternal immunotolerance is further facilitated by the activation of CD4+CD25brightFoxp3+ regulatory T (TREG) cells. Infections have to be prevented during pregnancy. The cells of placenta express 10 Toll-like receptors a group of pattern recognition receptors responsible for innate immunity. The interferon level is also higher in the placental tissues than in the somatic fetal or maternal cells. The complement system is also adapted to the requirements of the pregnancy and fetal damage is inhibited by the production of “assymmetric IgG antibodies” under hormonal and placental-regulation. These modifications prevent the activation of complement, cytotoxic activity, opsonising ability, antigen clearance and precipitating activity of the molecules. The Achilles’ heels of the different barriers are regularly found by virus infections. Lamina cribrosa of the blood-brain barrier, optical nerve of the eyes, etc. the risk factors of the maternal-fetal barrier has been summarised in Table 1.1.
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Dennison U, McKernan DP, Scully P, Clarke G, Cryan J, Dinan T. Menstrual cycle influences Toll-like receptor responses. Neuroimmunomodulation 2012; 19:171-9. [PMID: 22262081 DOI: 10.1159/000331424] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Accepted: 07/29/2011] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Toll-like receptors (TLRs) are pattern recognition receptors that play an important role as mediators of innate immunity. Human studies have shown changes in endometrial TLR expression during the menstrual cycle and during pregnancy. Our objective was to measure peripheral TLR activity over the course of the menstrual cycle. METHODS We recruited 11 healthy females, and using ELISA we measured sex hormone levels and IL-1β, IL-6, IL-8 and TNF-α following stimulation of whole blood with different TLR agonists during follicular, and early and late luteal phases of the menstrual cycle. RESULTS During the follicular phase, we observed lower levels of IL-6 and TNF-α following stimulation with the TLR2 agonist HKLM when compared with the early luteal phase; lower levels of IL-1β, IL-6 and TNF-α following stimulation with the TLR4 agonist LPS, and lower levels of IL-1β and TNF-α following stimulation with the TLR5 agonist flagellin. Decreased IL-6 levels in the late compared to the early luteal phase were also observed following stimulation with the TLR5 agonist flagellin. Compared with the follicular phase, the late luteal phase of the cycle resulted in decreased levels of IL-1β and TNF-α following stimulation with the TLR1/TLR2 agonist Pam3CSK and the TLR6/TLR2 agonist FSL1, as well as decreased levels of TNF-α following stimulation with the TLR8 agonist ssRNA40. There were no differences in cytokine release across the menstrual cycle following stimulation with the TLR3 agonist polyriboinosinic polyribocytidylic acid, or the TLR7 agonist Imiquimod. CONCLUSION This study is the first to demonstrate that TLR responsivity in peripheral blood fluctuates throughout the menstrual cycle.
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Affiliation(s)
- Una Dennison
- Department of Psychiatry, University College Cork, Cork, Ireland.
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Inflammatory-induced hibernation in the fetus: priming of fetal sheep metabolism correlates with developmental brain injury. PLoS One 2011; 6:e29503. [PMID: 22242129 PMCID: PMC3248450 DOI: 10.1371/journal.pone.0029503] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Accepted: 11/29/2011] [Indexed: 02/02/2023] Open
Abstract
Prenatal inflammation is considered an important factor contributing to preterm birth and neonatal mortality and morbidity. The impact of prenatal inflammation on fetal bioenergetic status and the correlation of specific metabolites to inflammatory-induced developmental brain injury are unknown. We used a global metabolomics approach to examine plasma metabolites differentially regulated by intrauterine inflammation. Preterm-equivalent sheep fetuses were randomized to i.v. bolus infusion of either saline-vehicle or LPS. Blood samples were collected at baseline 2 h, 6 h and daily up to 10 days for metabolite quantification. Animals were killed at 10 days after LPS injection, and brain injury was assessed by histopathology. We detected both acute and delayed effects of LPS on fetal metabolism, with a long-term down-regulation of fetal energy metabolism. Within the first 3 days after LPS, 121 metabolites were up-regulated or down-regulated. A transient phase (4–6 days), in which metabolite levels recovered to baseline, was followed by a second phase marked by an opposing down-regulation of energy metabolites, increased pO2 and increased markers of inflammation and ADMA. The characteristics of the metabolite response to LPS in these two phases, defined as 2 h to 2 days and at 6–9 days, respectively, were strongly correlated with white and grey matter volumes at 10 days recovery. Based on these results we propose a novel concept of inflammatory-induced hibernation of the fetus. Inflammatory priming of fetal metabolism correlated with measures of brain injury, suggesting potential for future biomarker research and the identification of therapeutic targets.
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Pineda A, Verdin-Terán SL, Camacho A, Moreno-Fierros L. Expression of toll-like receptor TLR-2, TLR-3, TLR-4 and TLR-9 is increased in placentas from patients with preeclampsia. Arch Med Res 2011; 42:382-91. [PMID: 21843566 DOI: 10.1016/j.arcmed.2011.08.003] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Accepted: 07/26/2011] [Indexed: 01/24/2023]
Abstract
BACKGROUND AND AIMS Few studies have examined the presence of Toll-like receptors (TLRs) in term placentas from women with preeclampsia, such, have focused on TLR-4 and TLR-2 analysis. Whereas an increase in TLR-4 immunostaining has been observed in preeclampsia, it is even higher in placentas with chorioamnionitis compared with normal pregnancy. Expression of TLR-2 has not been associated with preeclampsia. The relationship of TLR-3 and TLR-9, which may recognize dsRNA or DNA, either derived either from microorganisms or from apoptotic cells and thus may be involved with this pathology, has not been studied in term placentas. We undertook this study to determine if there are changes in the expression and localization of TLR-2, TLR-4, TLR-3 and TLR-9 in preeclamptic term placentas as compared with normal placentas. METHODS A prospective, cross-sectional and comparative study was done in a group of ten patients with 38-40 gestation weeks, both in preeclamptic and control cases. Immunofluorescence detection of TLRs was performed in samples of placenta and analyzed by confocal microscopy. RESULTS It was observed that TLR-2, TLR-3, TLR-4 and TLR-9 were expressed both in normal and preeclamptic placentas, in the trophoblast, at the vascular endothelium (where TLR-2 and TLR-9 staining was pronounced), and at placental villous stroma, although increased expression was detected in preeclampsia. In addition, co-localization of TLR-2 and TLR-4 as well as of TLR-3 and TL9 was found in the trophoblast. CONCLUSIONS TLR-2, -3, -4 and -9 expressions are increased in preeclamptic placentas. However, more studies are required to determine the role of TLRs in pregnancy immunology and to establish its relationship with preeclampsia.
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Affiliation(s)
- Antonio Pineda
- Unidad de Medicina Familiar, Instituto Mexicano de Seguro Social, Estado de México
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Nitsche JF, Jiang SW, Brost BC. Toll-like receptor-2 and toll-like receptor-4 expression on maternal neutrophils during pregnancy. Am J Reprod Immunol 2011; 64:427-34. [PMID: 20618182 DOI: 10.1111/j.1600-0897.2010.00891.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
PROBLEM Toll-like receptors (TLR) are an important part of the innate immune system and are present in a variety of human tissues. Work investigating the role of the TLR in pregnancy has thus far focused on placental tissue; however, minimal data is currently available concerning TLR expression in other tissues. Unlike placental tissue, neutrophils are easily retrievable during pregnancy and thus allow assessment of TLR’s prior to delivery. METHOD OF STUDY Using real time quantitative PCR this study investigated whether TLR-2 and TLR-4 expression on maternal neutrophils is altered throughout gestation or at the time of labor. A group of 12 non-pregnant women and two groups of ten pregnant patients were enrolled and followed longitudinally, one group throughout gestation and one group throughout the third trimester. RESULTS Although increased in the placenta, TLR2 and TLR4 expression on maternal neutrophils changes minimally throughout gestation. CONCLUSION There appears to be very little regulation of TLR2 and TLR4 at the mRNA level during normal pregnancy and labor. However, now that the normal values of TLR expression on maternal neutrophils have been determined it will be possible to compare them to those from pregnancies complicated by such conditions as preeclampsia, preterm labor, or preterm premature rupture of membranes.
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Affiliation(s)
- Joshua F Nitsche
- Division of Maternal Fetal Medicine, Department of OB ⁄ GYN, Mayo Clinic College of Medicine, Rochester, MN 55901, USA.
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Oligonucleotide microarray analysis of age-related gene expression profiles in miniature pigs. PLoS One 2011; 6:e19761. [PMID: 21603646 PMCID: PMC3094450 DOI: 10.1371/journal.pone.0019761] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Accepted: 04/12/2011] [Indexed: 01/12/2023] Open
Abstract
Miniature pigs are useful model animals for humans because they have similar anatomy and digestive physiology to humans and are easy to breed and handle. In this study, whole blood microarray analyses were conducted to evaluate variations of correlation among individuals and ages using specific pathogen-free (SPF) Clawn miniature pigs. Whole blood RNA is easy to handle compared to isolated white blood cell RNA and can be used for health and disease monitoring and animal control. In addition, whole blood is a heterogeneous mixture of subpopulation cells. Once a great change occurs in composition and expressing condition of subpopulations, their associated change will be reflected on whole blood RNA. From 12 to 30 weeks of age, fractions of lymphocytes, monocytes, neutrophils, eosinophils, and basophils in white blood cells showed insignificant differences with age as a result of ANOVA analysis. This study attempted to identify characteristics of age-related gene expression by taking into account the change in the number of expressed genes by age and similarities of gene expression intensity between individuals. As a result, the number of expressed genes was less in fetal stage and infancy period but increased with age, reaching a steady state of gene expression after 20 weeks of age. Variation in gene expression intensity within the same age was great in fetal stage and infancy period, but converged with age. The variation between 20 and 30 weeks of age was comparable to that among 30 weeks individuals. These results indicate that uniformity of laboratory animals is expected for miniature pigs after 20 weeks of age. Furthermore, a possibility was shown that whole blood RNA analysis is applicable to evaluation of physiological state.
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Rose JA, Rabenold JJ, Parast MM, Milstone DS, Abrahams VM, Riley JK. Peptidoglycan induces necrosis and regulates cytokine production in murine trophoblast stem cells. Am J Reprod Immunol 2011; 66:209-22. [PMID: 21385270 DOI: 10.1111/j.1600-0897.2011.00986.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
PROBLEM Intrauterine bacterial infection during pregnancy may lead to adverse outcome. The objective of this study was to assess whether peptidoglycan (PGN) derived from Gram-positive bacteria induces trophoblast stem (TS) cell death or alters TS cell cytokine production. METHOD OF STUDY Toll-like receptor (TLR) transcript expression was assessed by RT-PCR. Protein expression was determined by confocal microscopy or flow cytometry. 7-Aminoactinomycin D (7-AAD) staining was used to assess TS cell death. Morphological features of cell death were evaluated by transmission electron microscopy. The presence of cleaved caspase-3 and high mobility group box 1 (HMGB1) protein was examined by Western blot. Cytokine levels in cell supernatants were determined using a mouse cytokine 23-plex panel. RESULTS Toll-like receptor 2 and TLR4 protein was expressed from the 1-cell stage through the blastocyst stage of murine embryo development. Murine TS cells expressed TLR2 and TLR6 but not TLR1 or TLR4 RNA. Only TLR2 protein was detected at the plasma membrane of TS cells. PGN induced TS cell death by a caspase-3-independent mechanism. The cell death pathway induced by PGN was morphologically consistent with necrosis. Finally, PGN induced HMGB1 release and increased MIP-1β secretion while inhibiting the constitutive release of RANTES. CONCLUSION Peptidoglycan-induced TS cell necrosis and the subsequent release of HMGB1 and MIP-1β may regulate an infection-induced inflammatory response at the maternal-fetal interface and thus may play a role in the pathogenesis of infection-associated pregnancy complications.
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Affiliation(s)
- Jennifer A Rose
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St Louis, MO 63110, USA
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Riley JK, Nelson DM. Toll-like receptors in pregnancy disorders and placental dysfunction. Clin Rev Allergy Immunol 2011; 39:185-93. [PMID: 19866377 DOI: 10.1007/s12016-009-8178-2] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The Toll receptor was originally identified as a regulator of embryogenesis in Drosophila. Toll-like receptors (TLRs) in mammals recognize infectious agents and other danger signals. Activation of TLRs on trophoblast influences immune cell recruitment, cytokine secretion, and decidual responses to invading pathogens during pregnancy. Importantly, biological effects of TLR signal transduction at multiple maternal-fetal interfaces may contribute to several pregnancy pathologies associated with placental dysfunction, including pre-eclampsia, intrauterine growth restriction, and preterm labor. We herein discuss mechanisms by which TLRs regulate the maternal immune response during normal and abnormal gestation, and we highlight recent data that assign a role to TLRs in the pathophysiology of selected pregnancy-associated complications.
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Affiliation(s)
- Joan K Riley
- Department of Obstetrics and Gynecology, Washington University School of Medicine, 4566 Scott Ave, St. Louis, MO 63110, USA.
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66
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Ahn H, Park J, Gilman-Sachs A, Kwak-Kim J. Immunologic Characteristics of Preeclampsia, a Comprehensive Review. Am J Reprod Immunol 2010; 65:377-94. [DOI: 10.1111/j.1600-0897.2010.00913.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
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67
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Rappolee DA, Awonuga AO, Puscheck EE, Zhou S, Xie Y. Benzopyrene and experimental stressors cause compensatory differentiation in placental trophoblast stem cells. Syst Biol Reprod Med 2010; 56:168-83. [PMID: 20377314 DOI: 10.3109/19396360903431638] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Stress causes decreased cell accumulation in early periimplantation embryos and the placental trophoblast stem cells derived from them. Benzopyrene and many other stressors activate stress enzymes that lead to suppressed stem cell accumulation through diminished proliferation and increased apoptosis. Trophoblast stem cells proliferate and a subpopulation of early postimplantation trophoblast cells differentiate to produce the first placental hormones that arise in the implanting conceptus. These hormones mediate antiluteolytic effects that enable the continuation of a successful implantation. The normal determination and differentiation of placental trophoblast stem cells is dependent upon a series of transcription factors. But, these transcription factors can also be modulated by stress through the activity of stress enzymes. This review enumerates and analyzes recent reports on the effects of benzopyrene on placental function in terms of the emerging paradigm that placental differentiation from stem cells can be regulated when insufficient production of stem cells is caused by stress. In addition, we review the other effects caused by benzopyrene throughout placental development.
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Affiliation(s)
- Daniel A Rappolee
- C.S. Mott Center for Human Growth and Development, Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology and Infertility, Wayne State University School of Medicine, Detroit, MI 48201, USA.
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Koga K, Mor G. Toll-like receptors at the maternal-fetal interface in normal pregnancy and pregnancy disorders. Am J Reprod Immunol 2010; 63:587-600. [PMID: 20367625 DOI: 10.1111/j.1600-0897.2010.00848.x] [Citation(s) in RCA: 200] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Toll-like receptors (TLR) form the major family of pattern recognition receptors (PRR) that are involved in innate immunity. Innate immune responses against microorganisms at the maternal-fetal interface may have a significant impact on the success of pregnancy, as intrauterine infections have been shown to be strongly associated with certain disorders of pregnancy. At the maternal-fetal interface, TLRs are expressed not only in the immune cells but also in non-immune cells such as trophoblasts and decidual cells; moreover, their expression patterns vary according to the stage of pregnancy. Here, we will describe potential functions of TLRs in these cells, their recognition and response to microorganisms, and their involvement in the innate immunity. The impact of TLR-mediated innate immune response will be discussed via animal model studies, as well as clinical observations.
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Affiliation(s)
- Kaori Koga
- Department of Obstetrics and Gynecology, University of Tokyo School of Medicine, Tokyo, Japan
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69
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Mallard C, Wang X, Hagberg H. The role of Toll-like receptors in perinatal brain injury. Clin Perinatol 2009; 36:763-72, v-vi. [PMID: 19944834 DOI: 10.1016/j.clp.2009.07.009] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The toll-like receptors (TLRs) are a family of microbe-sensing receptors on peripheral immune cells. TLRs have also been discovered to be present in the brain, particularly in circumventricular organs, microglia, and astrocytes. Some TLRs are strongly expressed in the embryonic brain and TLR3 and TLR8 have been implicated in neurogenesis and neurite outgrowth in the developing brain, whereas TLR2 and TLR4 have been shown to regulate adult neurogenesis. TLR2 and TLR4 also play a role in acute ischemic brain injury in the adult, although no neuroprotection was observed following perinatal hypoxic-ischemic injury. These findings suggest that different TLRs have specific roles in the immature and adult brain following brain damage.
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Affiliation(s)
- Carina Mallard
- Department of Neuroscience and Physiology, Perinatal Center, Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 11, 41390 Gothenburg, Sweden
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70
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Koga K, Aldo PB, Mor G. Toll-like receptors and pregnancy: Trophoblast as modulators of the immune response. J Obstet Gynaecol Res 2009; 35:191-202. [DOI: 10.1111/j.1447-0756.2008.00963.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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71
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The adaptor protein MyD88 is essential for E coli-induced preterm delivery in mice. Am J Obstet Gynecol 2009; 200:93.e1-8. [PMID: 19121660 DOI: 10.1016/j.ajog.2008.08.038] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2008] [Revised: 06/24/2008] [Accepted: 08/19/2008] [Indexed: 02/06/2023]
Abstract
OBJECTIVE We used a mouse model of infection-induced preterm delivery to examine the roles of 2 adaptor proteins with central functions in Toll-like receptor signaling: MyD88 (myeloid differentiation primary-response gene 88) and TRIF (Toll/IL-1 receptor (TIR)-domain-containing adaptor protein-inducing IFN-beta). STUDY DESIGN Mice deficient (KO) for MyD88, TRIF, both (DKO) or neither (WT) were inoculated into the uterus with killed Escherichia coli. Delivery outcomes, fetal status, serum progesterone, and nuclear translocation of the transcription factor nuclear factor kappa B (NFkappaB) were determined. RESULTS Preterm birth (delivery in less than 48 hours) occurred in WT and TRIF-KO animals in a dose-dependent fashion, reaching 100% with 5-10 x 10(9) bacteria, while MyD88-KO and DKO animals were completely protected from delivery. Intrauterine fetal survival, maintenance of circulating progesterone levels, and nuclear translocation of NFkappaB were also dependent upon MyD88 but not TRIF. In contrast, induction of uterine interleukin (IL)-1beta and tumor necrosis factor alpha (TNF-alpha) depends upon actions of both MyD88 and TRIF. CONCLUSION E coli-induced preterm delivery in the mouse is completely dependent upon MyD88 but not TRIF.
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72
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Patni S, Wynen LP, Seager AL, Morgan G, White JO, Thornton CA. Expression and activity of Toll-like receptors 1-9 in the human term placenta and changes associated with labor at term. Biol Reprod 2008; 80:243-8. [PMID: 18815357 DOI: 10.1095/biolreprod.108.069252] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Inflammatory processes are involved in the initiation and maintenance of labor, suggesting that Toll-like receptor (TLR) activity within gestation-associated tissues, such as the placenta, might contribute to the process of parturition. Expression of transcripts for TLR1-TLR10 was examined in term (>37 wk of gestation) human placentas collected in the absence of labor (elective caesarean sections; ECS; n = 11) and after the completion of labor (normal vaginal delivery; NVD; n = 12). Placental explants were cultured in the presence of agonists for TLR2, TLR3, TLR4, TLR5, TLR7, TLR8, and TLR9, and cytokine production after 24 h was examined. All placentas expressed transcripts for TLR1-TLR10. Reactivity to all agonists except CpG oligonucleotides was observed, indicating that, other than TLR9, all of the receptors studied yielded functional responses. Placental explants prepared from NVD placentas (n = 17) produced significantly more TNFA in response to lipopolysaccharide (TLR4 agonist) and resiquimod (TLR7/8 agonist) than explants from ECS placentas (n = 17). In contrast, gene expression analysis revealed that only transcripts for TLR2 and TLR5 were significantly elevated in association with labor. The human term placenta expresses a variety of functional TLRs, indicating that this family of receptors has an important role in parturition via as yet undetermined cell types and signaling pathways.
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Affiliation(s)
- Shalini Patni
- Princess of Wales Maternity Unit, Birmingham Heartlands Hospital, Birmingham B9 5SS, United Kingdom
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73
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Mor G. Inflammation and pregnancy: the role of toll-like receptors in trophoblast-immune interaction. Ann N Y Acad Sci 2008; 1127:121-8. [PMID: 18443339 DOI: 10.1196/annals.1434.006] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
During normal pregnancy, the decidua is populated by a variety of leucocytes; however, cells of the innate immune system seem to dominate this tissue. Their presence suggests that the innate immune system is not indifferent to the fetus and has been associated with a response of the maternal immune system to the "semi-allograft fetus." New evidences, however, indicates that these immune cells are critical for decidual and trophoblast development, rather than induction of tolerance. We hypothesized that, during implantation, an inflammatory environment is necessary for the attachment and invasion of the blastocyst. Therefore, we propose the existence of an "inflammatory-mediated embryo implantation" condition that is dependent on the proper "education" of the innate immune system by the trophoblast. Here we postulate that trophoblast cells successfully orchestrate their inflammatory environment and regulate immune cell differentiation and activation.
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Affiliation(s)
- Gil Mor
- Department of Obstetrics, Gynecology & Reproductive Sciences, Reproductive Immunology Unit, Yale University School of Medicine, 333 Cedar St., FMB 301, New Haven, CT 06520, USA.
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74
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Koga K, Mor G. Expression and function of toll-like receptors at the maternal-fetal interface. Reprod Sci 2008; 15:231-42. [PMID: 18421019 DOI: 10.1177/1933719108316391] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Toll-like receptors (TLRs) form the major family of pattern recognition receptors that are involved in innate immunity. Innate immune responses against microorganisms at the maternal-fetal interface may have a significant impact on the success of pregnancy because intrauterine infections have been shown to be strongly associated with certain complications of pregnancy. At the maternal-fetal interface, TLRs are expressed not only in the immune cells but also in nonimmune cells such as trophoblasts and decidual cells. Moreover, their expression patterns vary according to the stage of pregnancy. Here we will describe potential functions of TLRs in these cells, their recognition and response to microorganisms, and their involvement in the innate immunity. The impact of TLR-mediated innate immune response will be discussed via animal model studies, as well as clinical observations.
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Affiliation(s)
- Kaori Koga
- Department of Obstetrics, Gynecology & Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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75
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Patni S, Flynn P, Wynen LP, Seager AL, Morgan G, White JO, Thornton CA. An introduction to Toll-like receptors and their possible role in the initiation of labour. BJOG 2007; 114:1326-34. [PMID: 17903232 DOI: 10.1111/j.1471-0528.2007.01488.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Toll-like receptors (TLR) have emerged as key upstream mediators of inflammation at many tissue sites in humans. Inflammatory processes are involved in the process of parturition suggesting that TLR activity within gestation-associated tissues might have an important role in the initiation and/or maintenance of normal term labour and in various pathological states of pregnancy such as infection-associated preterm labour. Either TLRs or their signalling molecules might be excellent therapeutic targets for prevention of preterm labour.
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Affiliation(s)
- S Patni
- Department of Obstetrics and Gynaecology, Singleton Hospital, Swansea, UK.
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76
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Levy O. Innate immunity of the newborn: basic mechanisms and clinical correlates. Nat Rev Immunol 2007; 7:379-90. [PMID: 17457344 DOI: 10.1038/nri2075] [Citation(s) in RCA: 854] [Impact Index Per Article: 50.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The fetus and newborn face a complex set of immunological demands, including protection against infection, avoidance of harmful inflammatory immune responses that can lead to pre-term delivery, and balancing the transition from a sterile intra-uterine environment to a world that is rich in foreign antigens. These demands shape a distinct neonatal innate immune system that is biased against the production of pro-inflammatory cytokines. This bias renders newborns at risk of infection and impairs responses to many vaccines. This Review describes innate immunity in newborns and discusses how this knowledge might be used to prevent and treat infection in this vulnerable population.
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Affiliation(s)
- Ofer Levy
- Department of Medicine, Division of Infectious Diseases, Children's Hospital Boston and Harvard Medical School, Boston, MA 02115, USA.
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77
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Girling JE, Hedger MP. Toll‐like receptors in the gonads and reproductive tract: emerging roles in reproductive physiology and pathology. Immunol Cell Biol 2007; 85:481-9. [PMID: 17592495 DOI: 10.1038/sj.icb.7100086] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Interactions between the immune system and reproductive system have important consequences for fertility and reproductive health in general. There is increasing evidence that many of the interactions between the immune and reproductive systems involve the Toll-like receptors (TLRs). While there is no doubt that TLRs are important in providing protection against infection in the reproductive tract, there is increasing evidence for the involvement of TLRs in more basic pathology and physiology of reproduction. In the female, TLRs have been implicated in critical aspects of ovarian, endometrial and placental function, as well as in ovarian cancer, pelvic inflammatory disease, intrauterine growth restriction, pre-eclampsia and preterm birth. In the male, TLRs appear to play a role in the control of testicular steroidogenesis and spermatogenesis in disease and, potentially, during normal function, as well. Recent studies also have begun to highlight the role of various TLRs in the aetiology of prostatitis and prostatic cancer. Given the nascent state of knowledge concerning this important area, it is clear that more studies are needed, which should provide valuable new insights into the biology of the TLRs and reproductive function in general.
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Affiliation(s)
- Jane E Girling
- Centre for Women's Health Research, Monash Institute of Medical Research, Monash University, Melbourne, Victoria, Australia.
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78
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Ma Y, Krikun G, Abrahams VM, Mor G, Guller S. Cell type-specific expression and function of toll-like receptors 2 and 4 in human placenta: implications in fetal infection. Placenta 2007; 28:1024-31. [PMID: 17588655 PMCID: PMC2064901 DOI: 10.1016/j.placenta.2007.05.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2006] [Revised: 04/26/2007] [Accepted: 05/07/2007] [Indexed: 02/03/2023]
Abstract
Placental infection is associated with adverse fetal outcomes. Toll-like receptors (TLRs) are critical regulators of the innate immune response based on their ability to recognize and respond to pathogen-associated molecular patterns expressed by microbes. To date, cell-type specific expression and regulation of TLR function in human term placenta remains largely unelucidated. The goal of the current study was to examine the in vivo and in vitro patterns of TLR expression and function in major cell types of term placenta. Immunohistochemical analysis of terminal and stem villi localized TLR-2, which recognizes peptidoglycan (PG) from Gram-positive bacteria, to endothelial cells and macrophages, and to a lesser extent to syncytiotrophoblast (SCTs) and fibroblasts (FIBs). Staining for TLR-4, the receptor for Gram-negative bacterial lipopolysaccharide (LPS), was most prominent in SCTs and endothelial cells. Results from Western blotting, conventional, and quantitative PCR (qRTPCR) analyses using protein and mRNA isolated from cultures of SCTs and myofibroblasts (mFIBs) revealed that SCTs expressed TLR-2 and TLR-4, whereas mFIBs expressed only TLR-4. In addition, qRTPCR showed that LPS treatment increased TLR-2 expression in SCTs, indicating that infection with Gram-negative bacteria may enhance innate immune responses in placenta toward a broad range of microorganisms. In addition, treatment with LPS increased IL-8 levels in both SCTs and mFIBs, whereas PG treatment only stimulated IL-8 levels in SCTs. Our results indicate that there exist cell type-specific patterns of TLR function in placenta which likely regulate innate immune response at the maternal-fetal interface.
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Affiliation(s)
- Y Ma
- Department of Obstetrics/Gynecology and Reproductive Sciences, Yale University School of Medicine, 333 Cedar Street-339 FMB, PO Box 208063, New Haven, CT 06520-8063, USA
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Canavan TP, Simhan HN. Innate immune function of the human decidual cell at the maternal–fetal interface. J Reprod Immunol 2007; 74:46-52. [PMID: 17196257 DOI: 10.1016/j.jri.2006.10.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2006] [Revised: 09/26/2006] [Accepted: 10/16/2006] [Indexed: 01/29/2023]
Abstract
The aim of the study was to investigate the innate immune function of decidual cells from term unlabored pregnancies by determining Toll-like receptor presence and function. Using immunohistochemistry, reverse transcriptase polymerase chain reaction and NF-kappaB-luciferase plasmid transfection, Toll-like receptor presence and function was determined. Decidual cells express Toll-like receptors 1, 2, 4 and 6 which respond to lipopolysaccharide and peptidoglycan stimulation producing Interleukin-8. Decidual cells from women at term have innate immune function and are capable of producing Interleukin responses to bacterial ligands.
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Affiliation(s)
- Timothy P Canavan
- University of Pittsburgh School of Medicine, Magee Womens Hospital, Department of Obstetrics, Gynecology and Reproductive Sciences, 300 Halket Street, Pittsburgh, PA 15213, USA.
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Intracellular expression of toll-like receptor 4 in neuroblastoma cells and their unresponsiveness to lipopolysaccharide. BMC Cancer 2006; 6:281. [PMID: 17156435 PMCID: PMC1705811 DOI: 10.1186/1471-2407-6-281] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2006] [Accepted: 12/08/2006] [Indexed: 02/08/2023] Open
Abstract
Background Recently it has been reported that, toll-like receptors (TLRs) are expressed on a series of tumor cells, such as colon cancer, breast cancer, prostate cancer, melanoma and lung cancer. Although some cancer cells like melanoma cells are known to respond to lipopolysaccharide (LPS) via TLR4, not all cancer cells are positive for TLR4. There is little information on the expression and function of TLR4 in neuroblastoma cells. In this study, we investigated the expression of TLR4 in human neuroblastoma NB-1 cell line. Methods Expression and localization of TLR4 were detected by reverse transcription-polymerase chain reaction (RT-PCR) and flow cytometric analysis, respectively. Activation of nuclear factor (NF)-κB by LPS was detected by degradation of IκB-α and NF-κB luciferase assay. Activation and expression of mitogen-activated protein (MAP) kinase and interferon regulatory factor (IRF)-3 was detected by immunoblot analysis. Results Human NB-1 neuroblastoma cells expressed intracellular form of TLR4, but not the cell surface form. Further, NB-1 cells express CD14, MD2 and MyD88, which are required for LPS response. However, LPS did not significantly induce NF-κB activation in NB-1 cells although it slightly degraded IκB-α. NB-1 cells expressed no IRF-3, which plays a pivotal role on the MyD88-independent pathway of LPS signaling. Collectively, NB-1 cells are capable to avoid their response to LPS. Conclusion Although human NB-1 neuroblastoma cells possessed all the molecules required for LPS response, they did not respond to LPS. It might be responsible for intracellular expression of TLR4 or lack of IRF-3.
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Benjamin JT, Smith RJ, Halloran BA, Day TJ, Kelly DR, Prince LS. FGF-10 is decreased in bronchopulmonary dysplasia and suppressed by Toll-like receptor activation. Am J Physiol Lung Cell Mol Physiol 2006; 292:L550-8. [PMID: 17071719 DOI: 10.1152/ajplung.00329.2006] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Many extremely preterm infants continue to suffer from bronchopulmonary dysplasia, which results from abnormal saccular-stage lung development. Here, we show that fibroblast growth factor-10 (FGF-10) is required for saccular lung development and reduced in the lung tissue of infants with bronchopulmonary dysplasia. Although exposure to bacteria increases the risk of bronchopulmonary dysplasia, no molecular target has been identified connecting inflammatory stimuli and abnormal lung development. In an experimental mouse model of saccular lung development, activation of Toll-like receptor 2 (TLR2) or Toll-like receptor 4 (TLR4) inhibited FGF-10 expression, leading to abnormal saccular airway morphogenesis. In addition, Toll-mediated FGF-10 inhibition disrupted the normal positioning of myofibroblasts around saccular airways, similar to the mislocalization of myofibroblasts seen in patients with bronchopulmonary dysplasia. Reduced FGF-10 expression may therefore link the innate immune system and impaired lung development in bronchopulmonary dysplasia.
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Affiliation(s)
- John T Benjamin
- Departments of Pediatrics, Children's Hospital of Alabama, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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LPS induces translocation of TLR4 in amniotic epithelium. Placenta 2006; 28:477-81. [PMID: 17055575 DOI: 10.1016/j.placenta.2006.08.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2006] [Revised: 08/17/2006] [Accepted: 08/25/2006] [Indexed: 02/07/2023]
Abstract
Toll-like receptor 4 (TLR4) mediates lipopolysaccharide (LPS) induced immune responses, which may contribute to preterm labor associated with intraamniotic gram-negative bacterial infections. The study objective was to investigate gestational age and LPS-induced changes in TLR4 subcellular localization within amniotic epithelium, the first line of host defense against intraamniotic bacteria. TLR4 localization in amniotic epithelium was assessed using immunohistochemistry on 24 placentas of different gestational ages: first trimester (n=6), second trimester (n=6), and third trimester (n=12). Immunofluorescence was used to determine TLR4 localization following ex vivo LPS stimulation of amnion from women undergoing cesarean section without labor at term. TLR4 was expressed in the cytoplasm of amniotic epithelium starting at 9weeks with apical polarization by 25weeks gestation. TLR4 localization to the basal membrane was significantly associated with chorioamnionitis (p=0.01). After LPS stimulation, TLR4 was expressed sequentially within the apical membrane, cytoplasm, and finally in the basal cellular compartment. This suggests that TLR4 expression in amniotic epithelium is poised to monitor amniotic fluid for pathogens. TLR4 translocation to the basal membrane may decrease LPS signaling early in an infection, but allow the amniotic epithelium to remain competent to invasive or intracellular bacteria.
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