Journal of Reproductive Immunology

Editorial Board

2012-06-01

Trophoblast debris modulates the expression of immune proteins in macrophages: a key to maternal tolerance of the fetal allograft?

M.H. Abumaree, L.W. Chamley, M. Badri, M.F. El-Muzaini — 2012-04-23

Abstract: Interactions between maternal immune cells and the placenta are of substantial interest since diseases of pregnancy, such as recurrent miscarriage, villitis of unknown etiology and preeclampsia may arise due to inadequate adaptation of the maternal immune system. During normal pregnancy trophoblast debris is shed from the placenta into the maternal blood in large quantities. This trophoblast debris is then rapidly cleared from the maternal circulation. In this study, we exposed trophoblast debris generated from an in vitro placental explant model to peripheral blood-derived macrophages and quantified a variety of molecules that are important in immune responses by ELISA or flow cytometry. Phagocytosis of trophoblast debris resulted in reduced cell-surface expression of MHC-II molecules, the costimulatory molecules (CD80, CD86, CD40 and B7H3), monocyte chemoattractant protein-1 (MCP-1), inter-cellular adhesion molecule 1 (ICAM-1) and IL-8 receptors in macrophages while the expression of programmed death-1 ligand 1 (PD-L1) was upregulated. In addition, phagocytosis of trophoblast debris induced the secretion of the anti-inflammatory cytokines IL-10, IL6 and IL1Ra and decreased the secretion of pro-inflammatory cytokines IL-1β, IL12p70 and IL-8 by macrophages. Phagocytosis of trophoblast debris also increased macrophage expression of the immunosuppressive enzyme indoleamine 2,3-dioxygenase (IDO). We have shown that phagocytosis of trophoblast debris from normal placentae alters the phenotype of macrophages such that they are likely to deviate maternal immune responses towards tolerance and away from inflammation. This may be one of the mechanisms that allow the human fetal allograft to survive in direct contact with the maternal immune system.

The N-linked carbohydrate moiety of male reproductive tract CD52 (mrt-CD52) interferes with the complement system via binding to C1q

Lutfi Hardiyanto, Akiko Hasegawa, Shinji Komori — 2012-02-20

Abstract: Antisperm antibody detected in infertile female patients’ sera has been shown to correlate with reduced fertility. The antibody showed strong complement-dependent cytotoxicity as determined by the sperm immobilization test (SIT). CD52 is a human glycosylphosphatidylinositol (GPI)-anchored antigen present in lymphocytes and male reproductive tracts (mrt), including mature sperm and seminal plasma. Recently, purified mrt-CD52 from human seminal plasma has been reported to interfere with the classical complement pathway, but not lectin binding or alternative pathways of the complement system. The purpose of this study is to determine which stage of the classical pathway mrt-CD52 regulates. mrt-CD52 was purified from human seminal plasma or intact sperm membrane. Immunoprecipitation assay was performed with the reaction of mrt-CD52, human complement and mAb H6-3C4. Immunoprecipitate was formed by the carbohydrate moiety of mrt-CD52, but not by the GPI-anchor peptide. The C1q molecule (29kDa) was detected in the immunoprecipitates by Western blotting analysis probed with anti C1q antibody, indicating that the carbohydrate moiety of mrt-CD52 binds to C1q. Also, the complement-dependent SIT revealed that purified CD52 inhibited sperm immobilization activity by antisperm antibody. These results suggest that mrt-CD52 protects sperm function from complement attack if antisperm antibody is generated in the female reproductive tracts.

Transcriptomic analysis of placenta affected by antiphospholipid antibodies: following the TRAIL of trophoblast death

P. Pantham, R. Rosario, Q. Chen, C.G. Print, L.W. Chamley — 2012-04-23

Abstract: Antiphospholipid antibodies, a maternal risk factor for preeclampsia, increase shedding of necrotic trophoblast debris from the placenta, leading to endothelial dysfunction. Using Affymetrix HGU133 Plus 2 microarrays we found changes in the transcriptome of placental explants treated with antiphospholipid antibodies, including mRNAs BCL2L1, MCL1, PDCD2L, FASLG, SEMA6A, PRKCE and TRAIL that are involved in the regulation of apoptosis. Quantitative real-time RT-PCR and immunohistochemistry confirmed a reduction in TRAIL expression in response to antiphospholipid antibodies. These results may help to understand how antiphospholipid antibodies affect trophoblast cell death and how the antibodies could contribute to the pathogenesis of preeclampsia.

Effects of lipopolysaccharide exposure at different postnatal time points on the response of LH to homotypic stress in adulthood

2012-02-20

Abstract: Early-life immune stress may have long-lasting effects, known as programming effects, on the physiological response to stress in adulthood. There may be a critical window after birth during which such a challenge can induce long-lasting alterations. However, there are few reports regarding the consequences of this phenomenon for later reproductive function. Here we report on induction by early-life LPS injection of long-lasting alterations in the adult LH response to homotypic immune stress in male rats. First, we investigated developmental changes in the LH response to LPS, since immune challenge during the stress hyporesponsive period can induce long-lasting effects on physiological functions. Rat serum LH concentrations were decreased by LPS (100μg/kg) injection on postnatal day 15 or 25, but not day 10, suggesting that the period prior to postnatal day 10 is the stress hyporesponsive period for LH. Serum LH concentrations and body weight were decreased by adult LPS (400μg/kg) injection in rats given saline or LPS (100μg/kg) on postnatal day 25, but not in rats given LPS (100μg/kg) on postnatal day 10. Expression of hypothalamic IL-1β and TNF-α mRNA, which suppress serum LH during immune stress, were equally increased in these groups by adult LPS (400μg/kg) injection. The present data suggest that the period prior to postnatal day 10 is the critical window in which immune stress can induce long-lasting alterations in the LH response, but that IL-1β and TNF-α are not involved in mediating the altered response.

Effects of short-chain galacto- and long-chain fructo-oligosaccharides on systemic and local immune status during pregnancy

2012-03-19

Abstract: Nondigestible oligosaccharides can positively influence health via various mechanisms. During pregnancy, supplementation of nondigestible oligosaccharides has positive effects on hypertension and metabolism and may be used to ameliorate pregnancy-related metabolic disturbances. In the nonpregnant state, nondigestible oligosaccharides have been shown to induce a tolerogenic immune response mediated by T-regulatory cells. Since relatively little is known about the effects of nondigestible oligosaccharides on the immune system during pregnancy, pregnant mice were supplemented with a specific mixture of short-chain galacto- and long-chain fructo-oligosaccharides (scGOS/lcFOS; ratio 9:1). Systemic and local immune parameters were analyzed on day 18 of pregnancy. This study shows that, compared with virgin mice, scGOS/lcFOS supplementation appears to elicit a more tolerogenic immune reaction in pregnant mice and supplementation does not increase the Th1-dependent delayed type hypersensitivity response in pregnant mice as it does in virgin mice.

Ontogeny of the interferon system in chickens

2012-03-22

Abstract: Newborn vertebrates may be susceptible to infection because the immature status of their immune system results in an inability to make an effective immune response. Consequently, newly hatched chicks appear to be more susceptible to infections than mature chickens. In particular, poultry susceptibility to virus infection may be related to poor expression of innate immune elements involved in antiviral responses. Therefore, in this study we assessed the relative development of the interferon (IFN) system: a protective system against virus infection. We investigated the age-related expression of the elements involved in the IFN response including IFN gene expression, their associated receptors and the pattern recognition receptors (PRR) involved in the regulation of IFNs. We observed that the IFN system is somewhat inadequately expressed in embryos and develops over time, just prior to and after hatching, and therefore chicks may be more susceptible to virus than mature birds because of an immature IFN network.

LIF and sIL-2R plasma concentrations in IVF patients on the day of embryo transfer: predictive markers of IVF outcome

2012-03-09

Abstract: Successful implantation is still the limiting step in IVF. We hypothesized that maternal plasma concentrations of certain cytokines at the time of embryo transfer could predict the likelihood of successful implantation and pregnancy. sIL-2R, IL-6, LIF, and MMP2 concentrations were measured in plasma from 160 IVF patients (natural and stimulated IVF cycles) on the morning of the embryo transfer (ET0) and 14days later (ET+14). Patients were ultimately subdivided into four groups depending on the IVF treatment outcome (pregnancy failure, biochemical pregnancy, first-trimester miscarriage and normal term delivery). In natural and stimulated IVF cycles at ET0, sIL-2R concentrations were threefold higher in biochemical pregnancies than in pregnancy failures (P=0.020), and in natural cycles only, 2.5-fold higher in normal term deliveries than in pregnancy failures (P=0.023). Conversely, in natural and stimulated IVF cycles at ET0, LIF concentrations were one third lower in biochemical pregnancies/first-trimester miscarriages compared with pregnancy failures (P=0.042). We suggest that high sIL-2R and low LIF concentrations in maternal plasma on the morning of the embryo transfer might be associated with increased risks of early pregnancy loss, while a basal level of sIL-2R is necessary for normal term delivery outcome. Both cytokine measurements might therefore be useful in the management of IVF patients, and modulation of their concentrations could be investigated as a therapeutic alternative for women with abnormal concentrations at the time of embryo transfer.

Impaired fetal thymic growth precedes clinical preeclampsia: a case–control study

2012-04-23

Abstract: In preeclampsia the maternal adaptive immune system undergoes specific changes, which are different from the physiological processes associated with healthy pregnancy. Whether preeclampsia also affects the fetal immune system is difficult to investigate, due to limited access to the fetus. We hypothesized that if preeclampsia affects the fetal adaptive immune system this might be associated with early changes in thymic growth. In this case–control study, 53 preeclamptic and 120 healthy control pregnancies were matched for maternal age, gestational age and smoking. Fetal thymus diameter was measured as the greatest width perpendicular to a line connecting sternum and spine based on ultrasound images taken at 17–21 weeks gestation. Independent of fetal and maternal anthropometric measures, thymuses were found to be smaller in preeclamptic pregnancies than healthy controls (16.2mm versus 18.3mm, respectively, mean difference=2.1mm, 95% CI: 0.8–3.3, p<0.001), and the odds of developing preeclampsia was estimated to be 0.72 (95% CI: 0.60–0.86, p<0.001) lower for each 1mm increase in thymus diameter. There was no correlation between the onset of preeclampsia and fetal thymus size. This is the first study to suggest that fetal thymus growth is reduced before the clinical onset of preeclampsia and precedes any described fetal anomalies or maternal immunological changes associated with preeclampsia. We propose that the fetal adaptive immune system is either passively affected by maternal processes preceding clinical preeclampsia or is actively involved in initiating preeclampsia in later pregnancy.

Analysis of monocyte subsets and toll-like receptor 4 expression in peripheral blood monocytes of women in preterm labor

2012-02-24

Abstract: Preterm labor is associated with both localized inflammation of the uterus and elevated proinflammatory cytokines. Recently, specific roles have been suggested for distinct monocyte subsets and toll-like receptor 4 (TLR4) expression in inflammation. The aim of this study was to determine whether specific monocyte subsets and increased TLR4 expression in monocyte subsets contribute to preterm labor. The study included 30 preterm labor, 40 full-term labor and 20 pregnant women (not in labor). Four-color flow cytometry was used to examine the distribution of three monocyte subsets (CD14+CD16−, CD14highCD16+, and CD14lowCD16+) and the TLR4 expression in each monocyte subset in each group of women. A larger percentage of CD14highCD16+ cells was found in the preterm labor group than in the other groups (P=0.08, P=0.06). Women in preterm labor also showed significantly higher TLR4 expression in all monocyte subsets and increased fluorescence intensity in the CD14+CD16− and CD14highCD16+ cells. Expression of TLR4 and mean fluorescence intensity on each monocyte subset were also significantly correlated. We conclude that women with preterm labor have higher CD16 monocytes, with high concomitant expression of CD14 and enhanced TLR4 expression in monocytes, and that monocyte TLR4 levels could be used as a marker to predict preterm delivery.

A retrospective study on IVF outcome in patients with anticardiolipin antibody: effects of methylprednisolone plus low-dose aspirin adjuvant treatment

2012-04-23

Abstract: Patients undergoing in vitro fertilization–embryo transfer have a high prevalence of anticardiolipin antibody (ACA). However, the relationship between ACA and IVF outcome is still controversial. The aim of the present study was to evaluate the potential effect of anticardiolipin antibody on IVF outcome and determine the role of adjuvant treatment in these ACA positive patients. The study included a total of 116 infertile women (116 IVF-ET cycles) positive for ACA, including 56 women pretreated with methylprednisolone plus low-dose aspirin before IVF (treated ACA+ group) and 60 patients without treatment (untreated ACA+ group). In addition, 518 infertile women (518 IVF-ET cycles) negative for ACA were enroled as controls (ACA− group). The results show that ACA+ patients who did not receive any adjuvant treatment showed a significantly lower fertilization rate, less high-quality embryos, as well as a markedly lower pregnancy rate and implantation rate than controls. Moreover, ACA+ patients who received methylprednisolone plus aspirin achieved significantly higher fertilization, pregnancy and implantation rates than untreated ACA+ patients (FR 69.0%, PR 46.4% and IR 25.4% vs. FR 60.0%, PR 33.3% and IR 17.9%, respectively). The overall IVF results in the treated ACA+ group were comparable to patients negative for ACA (PR 53.9% and IR 32.3%). Thus, while the presence of ACA exerts a detrimental effect on IVF outcome, ACA+ patients have a better outcome if given methylprednisolone for immunosuppression and low-dose aspirin as an anti-thrombotic agent.

Association of depressive symptoms with inflammatory biomarkers among pregnant African-American women

2012-02-20

Abstract: Depression and inflammation are associated with poorer birth outcomes. African-American women have higher levels of inflammatory biomarkers, more depressive symptoms, and a disparate burden of poorer birth outcomes, but the association between depressive symptoms and inflammation within this higher-risk group is unknown. We examined this association among African-American women in the second trimester of pregnancy and additionally tested whether body mass index (BMI) mediates or moderates this relationship. We recruited 187 women from the obstetrics clinics of a large urban health system. Depression symptoms were measured with the Center for Epidemiological Studies Depression (CES-D) scale and inflammatory biomarkers (high-sensitivity C-reactive protein [hs-CRP], interleukin [IL]-6, IL-10, IL-1β, and tumor necrosis factor-α [TNF-α]) with enzyme immunoassays. Multivariate regression models were fitted to determine the association between CES-D score and each inflammatory biomarker. CES-D was not associated with hs-CRP or TNF-α. CES-D was directly associated with IL-1β (P=0.03). BMI moderated the relationship between CES-D and IL-6 (P<0.01) and IL-10 (P=0.04); in leaner women, depressive symptoms were associated with higher IL-6 and IL-10 levels, whereas in heavier women, depressive symptoms were associated with lower IL-10 levels. BMI did not mediate the relationship between CES-D and inflammation. We conclude that depressive symptoms are associated with increased inflammation among pregnant African-American women. Future studies are needed to examine if depression, mediated through inflammation, increases the risk of adverse pregnancy outcomes in African-American women.

Dendritic cells in the circulation of women with preeclampsia demonstrate a pro-inflammatory bias secondary to dysregulation of TLR receptors

2012-02-23

Abstract: Toll-like receptors (TLRs) are central components of the innate immune system that recognize both microbial ligands and host products released during tissue damage. Data from epidemiologic studies and animal models suggest that inappropriate activation of the immune system plays a critical role in the development of preeclampsia. This study evaluates in a systematic fashion the expression and function of TLRs in the circulation of patients with preeclampsia compared to healthy pregnant controls.We evaluated TLR expression and function in primary dendritic cells (DCs) of 30 patients with preeclampsia and 30 gestational age-matched healthy pregnant controls. DCs were stimulated with the different TLR ligands engaging TLR1/2, TLR2/6, TLR3, TLR4, TLR5, TLR7, TLR8 and TLR9. The expression of TLR-induced production of TNF-α, IFN-α, IL-6, and IL-12 were measured by multicolor flow cytometry.Basal expression of TLR3, TLR4 and TLR9 was significantly increased in DCs isolated from women with preeclampsia. Preeclamptic DCs also expressed significantly higher basal levels of cytokines. In contrast, preeclamptic DCs demonstrated a less robust response to stimulation with various TLR ligands as compared with healthy pregnant controls.Under basal conditions, DCs from preeclamptic individuals express higher levels of select TLRs and produce more pro-inflammatory cytokines as compared with healthy controls. As such, the ability of these cells to mount an inflammatory reaction in response to a TLR ligand is limited. These data demonstrate a dysregulated pattern of TLR expression and cytokine production in DCs from PE patients that may limit further activation by TLR engagement.

Promoter region polymorphisms in the transforming growth factor beta-1 (TGFβ1) gene and serum TGFβ1 concentration in preeclamptic and control Iranian women

2012-03-19

Abstract: Preeclampsia (PE) is a pregnancy associated disorder characterized by hypertension and proteinuria, which causes neonatal and maternal morbidity and mortality. The Th1/Th2 cytokine paradigm of the immune adaptation in pregnancy is now expanded to include Th1/Th2/Th17 and regulatory T (Treg) cells. Among cytokines, TGFβ1 has properties that justify evaluation of its role in PE etiopathology. In this investigation the polymorphisms of the TGFβ1 gene at promoter region, positions −800G→A and −509C→T, were studied in 142 PE and 140 normal pregnant female subjects using PCR-RFLP. Additionally, serum TGFβ1 was determined by ELISA. At position −800G→A genotypes and allele frequencies showed no significant differences between PE patients (GG 73.9%; GA 21.1%; AA 4.93%) and normal control (GG 70%; GA 28.6%; AA 1.4%) women. However the AA genotype at this position was more frequent in PE patients than in the control group. At −509C→T position, genotypes and allele frequencies showed no significant differences between PE patients and control individuals. The CC genotype at −509C→T position was more prevalent in PE patients than in the control group. The mean serum TGFβ1 level was significantly higher (62.14ng/ml) in PE patients compared with pregnant and non-pregnant control groups (and 47.01 and 40.68ng/ml, respectively). In conclusion, the promoter region polymorphisms of TGFβ1 may not be associated with PE, but serum levels of this cytokine may contribute to the etiopathology of PE.

Outcomes and treatment of obstetrical antiphospholipid syndrome in women with low antiphospholipid antibody levels

2012-02-20

Abstract: Our objective was to determine whether there is a relationship between low antiphospholipid (aPL) antibody levels and the obstetrical complications of antiphospholipid syndrome (APS) and to analyze the impact of conventional APS treatment in patients with low aPL levels. To this end, we retrospectively reviewed the files of all patients referred to our unit (2003–2010) for unexplained pregnancy morbidity, with an aPL test result. We compared patients with APS confirmed by Sapporo criteria (Group 1) with patients with APS-like obstetrical complications with an aPL titer below the intermediate titer (Group 2). Overall, 57 patients were included (25 in Group 1; 32 in Group 2). Obstetrical events were recurrent spontaneous abortion <10th week of gestation (n=9 patients in Group 1; n=13 patients in Group 2), fetal death (n=11 and 16, respectively), preeclampsia (n=5 in Group 1; n=6 in Group 2). The total number of obstetrical events per patient was very similar before APS treatment (3 [1–8] in Group 1; 3 [1–6] in Group 2) and decreased significantly after APS treatment to 0 [0–2] and 0 [0–2], respectively (p<0.05). The incidence of premature births and the characteristics of neonates were similar in the two groups. In this study, treatment of patients with low aPL levels and APS-like obstetrical events was associated with outcomes similar to those found in otherwise normal women with recurrent miscarriage or other adverse events. However, properly designed treatment trials would be required to prove the benefit of such treatments.