IL-22 regulates endometrial regeneration by enhancing tight junctions and orchestrating extracellular matrix

The uterine endometrium uniquely regenerates after menses, postpartum, or after breaks in the uterine layer integrity throughout women’s lives. Direct cell–cell contacts ensured by tight and adherens junctions play an important role in endometrial integrity. Any changes in these junctions can alter the endometrial permeability of the uterus and have an impact on the regeneration of uterine layers. Interleukin 22 (IL-22) is a cytokine that is recognized for its role in epithelial regeneration. Moreover, it is crucial in controlling the inflammatory response in mucosal tissues. Here, we studied the role of IL-22 in endometrial recovery after inflammation-triggered abortion. Fecundity of mice was studied in consecutive matings of the same animals after lipopolysaccharide (LPS) (10 µg per mouse)-triggered abortion. The fecundity rate after the second mating was substantially different between IL-22 knockout (IL-22^−/−) (9.1%) and wild-type (WT) (71.4%) mice (p < 0.05), while there was no difference between the groups in the initial mating, suggesting that IL-22 deficiency might be associated with secondary infertility. A considerable difference was observed between IL-22^−/− and WT mice in the uterine clearance following LPS-triggered abortion. Gross examination of the uteri of IL-22^−/− mice revealed non-viable fetuses retained inside the horns (delayed clearance). In contrast, all WT mice had completed abortion with total clearance after LPS exposure. We also discovered that IL-22 deficiency is associated with a decreased expression of tight junctions (claudin-2 and claudin-10) and cell surface pathogen protectors (mucin-1). Moreover, IL-22 has a role in the remodeling of the uterine tissue in the inflammatory environment by regulating epithelial–mesenchymal transition markers called E- and N-cadherin. Therefore, IL-22 contributes to the proper regeneration of endometrial layers after inflammation-triggered abortion. Thus, it might have a practical significance to be utilized as a treatment option postpartum (enhanced regeneration function) and in secondary infertility caused by inflammation (enhanced barrier/protector function).

Pregnancy Outcome in Women With APECED (APS-1): A Multicenter Study on 43 Females With 83 Pregnancies

CONTEXT

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED; also known as autoimmune polyendocrine syndrome type 1) has a severe, unpredictable course. Autoimmunity and disease components may affect fertility and predispose to maternal and fetal complications, but pregnancy outcomes remain unknown.

OBJECTIVE

To assess fetal and maternal outcomes and course of clinical APECED manifestations during pregnancy in women with APECED.

DESIGN AND SETTING

A multicenter registry-based study including 5 national patient cohorts.

PATIENTS

321 females with APECED.

MAIN OUTCOME MEASURE

Number of pregnancies, miscarriages, and deliveries.

RESULTS

Forty-three patients had altogether 83 pregnancies at median age of 27 years (range, 17-39). Sixty (72%) pregnancies led to a delivery, including 2 stillbirths (2.4%) and 5 (6.0%) preterm livebirths. Miscarriages, induced abortions, and ectopic pregnancies were observed in 14 (17%), 8 (10%), and 1 (1.2%) pregnancies, respectively. Ovum donation resulted in 5 (6.0%) pregnancies. High maternal age, premature ovarian insufficiency, primary adrenal insufficiency, or hypoparathyroidism did not associate with miscarriages. Women with livebirth had, on average, 4 APECED manifestations (range 0-10); 78% had hypoparathyroidism, and 36% had primary adrenal insufficiency. APECED manifestations remained mostly stable during pregnancy, but in 1 case, development of primary adrenal insufficiency led to adrenal crisis and stillbirth. Birth weights were normal in >80% and apart from 1 neonatal death of a preterm baby, no serious perinatal complications occurred.

CONCLUSIONS

Outcome of pregnancy in women with APECED was generally favorable. However, APECED warrants careful maternal multidisciplinary follow-up from preconceptual care until puerperium.

Antithyroid antibodies may predict serum beta HCG levels and biochemical pregnancy losses in euthyroid women with IVF single embryo transfer

OBJECTIVE

To investigate the relationship between thyroid autoimmunity and early pregnancy serum β-HCG levels in intracytoplasmic sperm injection patients.

METHODS

The study subjects were 85 female euthyroid patients undergoing intracytoplasmic sperm injection embryo transfer cycles with GnRH antagonist treatment. Patients who received transfer of more than one embryo, those with serum TSH levels of greater than 2.5 IU/ml and subjects using levothyroxine were excluded. Normal responder patients under the age of 40 years were randomly selected from the patient files retrospectively. Subjects were divided into two groups: those with autoimmune thyroid disease (thyroid autoimmunity group; n = 39) and those without the disease (control group; n = 46).

RESULTS

The age, body mass index, trial number, total rFSH treatment dose, the number of cumulus oophorus complexes, number of metaphase II oocytes, and number of 2-pronuclei embryos were similar in the thyroid autoimmunity and control groups. Serum β-HCG levels measured on the 14th day after oocyte pickup were significantly lower in the thyroid autoimmunity group than in the control group (93.8 ± 35.8 versus 128.5 ± 55.8 mlU/ml, respectively; p < .001). The miscarriage rate was higher in the thyroid autoimmunity group than in the control group (34.4% versus 21.7%, respectively; p = .034).

CONCLUSION

We found that early-stage pregnancy serum β-HCG hormone levels among euthyroid patients undergoing intracytoplasmic sperm injection were lower in subjects with thyroid autoimmunity than in those without thyroid autoimmunity. This result, reported for the first time in the literature on euthyroid pregnant women with thyroid autoimmunity, may be predictor of early pregnancy losses in pregnant women with thyroid autoimmunity.Key messageIn intracytoplasmic sperm injection (ICSI)/IVF patients, due to lack of evidence-based data about the relationship between thyroid autoimmunity and pregnancy loss the current research was conducted. Early-stage pregnancy serum β-HCG hormone levels in euthyroid ICSI patients with thyroid autoimmunity are lower than those without autoimmunity which may be associated with early pregnancy losses.

The O-Linked N-Acetylglucosamine Containing Epitope H (O-GlcNAcH) is Upregulated in the Trophoblastic and Downregulated in the Fibroblastic Cells in Missed Miscarriage Human Chorionic Villi With Simple Hydropic Degeneration

Epitope H contains an O-linked N-acetylglucosamine (O-GlcNAcH) residue in a specific conformation and/or environment recognized by the mouse monoclonal antibody H. O-GlcNAcH is present in several types of cells and in several polypeptides, including cytokeratin 8 and vimentin, on the latter in cells under stress. In the present work, we examined the expression of the O-GlcNAcH in 60 cases of endometrial curettings from missed miscarriage cases containing normal and simple hydropic degenerated chorionic villi in each case, using monoclonal antibody H and indirect immunoperoxidase and Western blot immunoblot. In all cases examined the expression of the O-GlcNAcH was cytoplasmic as follows: (1) syncytiotrophoblastic cells showed very low expression in chorionic villi (CV) with nonhydropic degeneration (NHD) and high expression in hydropic degenerated (HD) CV; (2) cytotrophoblastic cells showed low expression in CV with NHD and high expression in HD CV; (3) fibroblastic cells showed high expression in CV with NHD and very low expression in HD CV; (4) histiocytes showed very low expression in both types of CV; (5) endothelial cells showed high expression in both types of CV. An immunoblot of CV from one case of a legal abortion from a normal first-trimester pregnancy showed 5 polypeptides with 118.5, 106.3, 85, 53, and 36.7 kD bearing the epitope H and the 53 kD corresponded to cytokeratin 8. The expression of the O-GlcNAcH is upregulated in the trophoblastic cells and downregulated in the fibroblastic cells in the HD CV in comparison to the NHD CV.

Toxoplasma Effectors that Affect Pregnancy Outcome

As an immune-privileged organ, the placenta can tolerate the introduction of antigens without inducing a strong inflammatory response that would lead to abortion. However, for the control of intracellular pathogens, a strong Th1 response characterized by the production of interferon-γ is needed. Thus, invasion of the placenta by intracellular parasites puts the maternal immune system in a quandary: The proinflammatory response needed to eliminate the pathogen can also lead to abortion. Toxoplasma is a highly successful parasite that causes lifelong chronic infections and is a major cause of abortions in humans and livestock. Here, we discuss how Toxoplasma strain type and parasite effectors influence host cell signaling pathways, and we speculate about how this might affect the outcome of gestation.

Risk factors for pregnancy morbidity in women with antiphospholipid syndrome

Antiphospholipid syndrome (APS) increases the risk of obstetric complications, but risk factors for pregnancy morbidity in women with APS remain incompletely characterized. This retrospective study included pregnant women with APS and a control group without APS admitted to Peking University People's Hospital between January 2013 and September 2019. Clinical data were extracted from medical records. Univariate and multivariate logistic regression analyses were used to identify factors associated with adverse pregnancy outcomes (fetal loss, premature birth, fetal growth restriction [FGR], preeclampsia and neonatal death). We included 64 pregnancies in 59 patients with APS (age, 32.3 ± 4.3 years) and 256 pregnancies in 256 women without APS (age, 30.4 ± 3.3 years). Compared with the control group, the APS group had higher incidence rates of preeclampsia (10.9 % vs. 2.3 %, P = 0.002), premature rupture of membranes (17.2 % vs. 3.9 %, P < 0.001), postpartum hemorrhage (23.4 % vs. 4.3 %, P < 0.001), fetal loss (4.7 % vs. 0.8 %, P = 0.024) and premature delivery at ≤34 weeks (7.8 % vs. 2.3 %, P = 0.047). The incidence rates of hypertension during pregnancy, HELLP syndrome, gestational diabetes, oligohydramnios and FGR were similar in both groups. Multivariate logistic regression revealed that three or more prior spontaneous miscarriages (odds ratio [OR], 6.162; 95 % confidence interval [CI], 1.271-29.882; P = 0.024) and double-positivity for antiphospholipid antibodies (OR, 4.024; 95 %CI, 1.025-15.794; P = 0.046) were independently associated with adverse pregnancy outcomes. APS increases the risks of adverse maternal and fetal outcomes during pregnancy. Three or more spontaneous miscarriages and double-positivity for antiphospholipid antibodies are risk factors for adverse pregnancy outcomes in women with APS.

Adoptive cell therapy with induced regulatory T cells normalises the abortion rate in abortion-prone mice

Ovarian hormones drive invivo generation of regulatory T cells (Tregs) during pregnancy. Little is known about the therapeutic potential of invitro hormone-derived Tregs in pregnancy loss. We investigated the effects of hormone-induced Tregs in a murine model of abortion. CD4+CD25- T cells were isolated from the spleens of CBA/J mice and stimulated with either 17β-oestradiol (E2), progesterone (P4) or transforming growth factor-β1 (TGFB1) plus retinoic acid (RA) for 4 days to generate induced Tregs (iTregs). On Days 1-4 of gestation, DBA/2-mated pregnant CBA/J female mice (abortion prone) were injected intravenously with iTregs or Tregs isolated from normal BALB/c-mated pregnant CBA/J mice (np-Tregs). On Day 14, the number of resorbed fetuses was assessed. Serum interferon (IFN)-γ and uterine forkhead box p3 (Foxp3) expression was analysed by ELISA and immunohistochemistry respectively. Using a 3H-thymidine incorporation assay, isolated CD4+CD25+ Tregs induced by the different treatments suppressed the proliferation of CD4+CD25- T cells. Adoptive transfer of iTregs (from all induction groups) significantly decreased fetal resorption in abortion-prone mice. There were no significant changes in serum IFN-γ concentrations after the adoptive transfer of iTregs or np-Tregs. Immunohistochemistry revealed significantly higher Foxp3 expression in gravid uteri from mice injected with np-Tregs and P4-induced iTregs than in the phosphate-buffered saline-treated group. The findings of this study indicate a potential therapeutic benefit of invitro-induced Tregs in patients with recurrent abortion.

miR-146a-5p improves the decidual cytokine microenvironment by regulating the toll-like receptor signaling pathway in unexplained spontaneous abortion

Spontaneous abortion (SA) is a common pregnancy failure, but the cause of numerous cases remains unexplained. Decidual immune cells (DICs)-mediated cytokine microenvironment is involved in pregnancy and regulated by many microRNAs, but whether microRNA-146a-5p (miR-146a) regulate the decidual cytokine microenvironment and the potential mechanisms in unexplained SA pathogenesis have rarely been reported. In this study, the levels of cytokines and miR-146a in healthy and unexplained SA deciduae were first investigated, and the correlation between them was analyzed. Then, the effect of miR-146a inhibitor on cytokines was assessed in healthy deciduae-derived DICs. Third, the downstream targets and related molecular mechanisms of miR-146a were analyzed by bioinformatics, and the levels of the predicted targets in deciduae were assessed, followed by the correlation analysis between the levels of miR-146a and the targets. Finally, the effect of miR-146a on the predicted targets and inflammatory cytokines was validated in unexplained SA deciduae-derived DICs. As a result, decreased miR-146a correlated with the cytokine disorder in unexplained SA deciduae, and inhibition of miR-146a promoted pro-inflammatory response in healthy deciduae-derived DICs. One hundred four target genes and related molecular mechanisms of miR-146a were predicted, among which the toll-like receptor (TLR) pathway might be associated with the decidual cytokine regulation. Upregulation of miR-146a inhibited the expression of the predicted molecules enriched in the TLR pathway and improved the cytokine disorder in unexplained SA deciduae-derived DICs. Collectively, miR-146a improves the decidual cytokine microenvironment by regulating the TLR pathway in unexplained SA, providing novel potential targets for further therapeutic research.

The Prevalence of Thyroid Dysfunction and Autoimmunity in Women With History of Miscarriage or Subfertility

OBJECTIVE

To describe the prevalence of and factors associated with different thyroid dysfunction phenotypes in women who are asymptomatic preconception.

DESIGN

Observational cohort study.

SETTING

A total of 49 hospitals across the United Kingdom between 2011 and 2016.

PARTICIPANTS

Women aged 16 to 41years with history of miscarriage or subfertility trying for a pregnancy.

METHODS

Prevalences and 95% confidence intervals (CIs) were estimated using the binomial exact method. Multivariate logistic regression analyses were conducted to identify risk factors for thyroid disease.

INTERVENTION

None.

MAIN OUTCOME MEASURE

Rates of thyroid dysfunction.

RESULTS

Thyroid function and thyroid peroxidase antibody (TPOAb) data were available for 19213 and 19237 women, respectively. The prevalence of abnormal thyroid function was 4.8% (95% CI, 4.5-5.1); euthyroidism was defined as levels of thyroid-stimulating hormone (TSH) of 0.44 to 4.50 mIU/L and free thyroxine (fT4) of 10 to 21 pmol/L. Overt hypothyroidism (TSH > 4.50 mIU/L, fT4 < 10 pmol/L) was present in 0.2% of women (95% CI, 0.1-0.3) and overt hyperthyroidism (TSH < 0.44 mIU/L, fT4 > 21 pmol/L) was present in 0.3% (95% CI, 0.2-0.3). The prevalence of subclinical hypothyroidism (SCH) using an upper TSH concentration of 4.50 mIU/L was 2.4% (95% CI, 2.1-2.6). Lowering the upper TSH to 2.50 mIU/L resulted in higher rates of SCH, 19.9% (95% CI, 19.3-20.5). Multiple regression analyses showed increased odds of SCH (TSH > 4.50 mIU/L) with body mass index (BMI) ≥ 35.0 kg/m2 (adjusted odds ratio [aOR] 1.71; 95% CI, 1.13-2.57; P = 0.01) and Asian ethnicity (aOR 1.76; 95% CI, 1.31-2.37; P < 0.001), and increased odds of SCH (TSH ≥ 2.50 mIU/L) with subfertility (aOR 1.16; 95% CI, 1.04-1.29; P = 0.008). TPOAb positivity was prevalent in 9.5% of women (95% CI, 9.1-9.9).

CONCLUSIONS

The prevalence of undiagnosed overt thyroid disease is low. SCH and TPOAb are common, particularly in women with higher BMI or of Asian ethnicity. A TSH cutoff of 2.50 mIU/L to define SCH results in a significant proportion of women potentially requiring levothyroxine treatment.

TPO antibody positivity and adverse pregnancy outcomes

Thyroid autoimmunity (TAI) is prevalent amongst women of reproductive age. TAI describes the presence of circulating anti-thyroid autoantibodies that are targeted against the thyroid, with or without thyroid dysfunction. Thyroid peroxidase antibodies (TPOAb) are the most common anti-thyroid autoantibodies. Around 10% of biochemically euthyroid individuals also have an elevated TPOAb titre. Many studies have linked the presence of TPOAb to adverse maternal and fetal outcomes in pregnancy, in particular miscarriage and pre-term birth, even in the absence of thyroid dysfunction. The causal pathway is poorly understood and few trials have looked to find treatments to reduce adverse outcomes. This review discusses in detail the associated adverse outcomes of TPOAb in pregnancy and the results of trials exploring methods to reduce such outcomes. Recommendations for counselling and monitoring of women with TPOAb and suggested areas for future work are also outlined.

Proliferative Activity of Mouse Splenocytes in Physiological Pregnancy and in Models of Spontaneous and Muramylpeptide-Dependent Abortions

Spontaneous proliferative activity of splenocytes in female CBA mice and the response of these cells to antigens of allogeneic male BALB/c and DBA/2 mice in a mixed splenocyte culture were evaluated by ³H-thymidine incorporation in different pregnancy models. ♀CBA×♂BALB/c mating was used for modeling physiological pregnancy. Spontaneous abortions were reproduced by abortion-prone ♀CBA×♂DBA/2 mating. In order to simulate immunostimulant-induced and immunostimulant-potentiated abortions, 0.83 mg/kg muramyl dipeptide β-heptylglycoside was intraperitoneally injected to CBA females mated with BALB/c or DBA/2 males, respectively, on gestation days 5 and 7. The increase in the rate of embryo resorption in the models of spontaneous, induced, and potentiated abortions occurred against the background of an increase in the level of spontaneous proliferation of splenocytes and a decrease in their reactivity to paternal antigens on gestation day 9.

Soluble urokinase plasminogen activator receptor (suPAR) as a biomarker of early pregnancy location and viability compared with hCG, progesterone and estradiol

A circulating biomarker of early pregnancy outcome independent of ultrasonography and gestational age is a coveted goal. This study evaluated soluble urokinase plasminogen activator receptor (suPAR), a well-described marker of inflammation and immunological activation, for this purpose, and compared it with established early pregnancy biomarkers of the luteoplacental phase: progesterone, estradiol and hCG. We merged data from two prospective first trimester cohorts to conduct a case-control study comparing these analytes in women who had either a live birth, a miscarriage or an ectopic pregnancy. The ability to predict pregnancy location and viability was assessed by areas under the receiver operating characteristic curves (AUC). Comparing women irrespective of gestational age with a live birth, miscarriage or ectopic pregnancy showed significantly lower suPAR values in the latter group (2.4 vs. 2.4 vs. 2.0 μg/L, p = 0.032, respectively), as were all other analytes. Before 6 weeks' gestation, suPAR was significantly inferior to progesterone, estradiol and hCG in pregnancy location and viability prediction (in 124 pregnancies, suPAR AUC_location = 0.69 [CI: 0.54-0.83] and AUC_viability = 0.58 [CI: 0.48-0.69], while progesterone AUC_location = 0.95 [CI: 0.87-1.00] and AUC_viability = 0.84 [CI: 0.75-0.92]). After 6 weeks' gestation, suPAR prediction improved but was inferior to hCG, progesterone and estradiol (in 188 pregnanices, suPAR AUC_location = 0.71 [CI: 0.63-0.78] and AUC_viability = 0.70 [CI: 0.63-0.78] compared with hCG AUC_location = 0.96 [CI: 0.93-0.99] and AUC_viability = 0.96 [CI: 0.93-0.98]). Collectively, suPAR is less useful as a predictor of early pregnancy outcome than hCG, progesterone and estradol.

Analysis of the frequency of type 2 innate lymphoid cells and regulatory T cells in abortion-prone mice

Recurrent spontaneous abortion (RSA) is the most common pregnancy related complication, affecting 1-5 % of pregnancies. Despite hormonal, genetic and anatomical factors that result in abortion, impairment of immune response at the feto-maternal interface during the first trimester of pregnancy is also one of the main causes of RSA. In the present study, we evaluated the frequency of blood and uterine group 2 innate lymphoid cells (ILC2s), their subsets and regulatory T cells (Tregs) in CBA/J × DBA/2 J as an abortion-prone model compared to normal pregnant (NP) mice using immunophenotyping. Results indicated that the percentages of ILC2s were significantly decreased in the AP group compared to the NP group at mid-gestation (P ≤ 0.01). Moreover, the percentages of both blood and uterine nILC2s were increased in NP mice at mid-gestation (P ≤ 0.01, and P ≤ 0.05, respectively), while iILC2s significantly increased in AP mice at mid-gestation (P ≤ 0.01, and P ≤ 0.05, respectively). Tregs were reduced in AP mice at both early and mid-gestation stages (P ≤ 0.01). Overall, our findings suggest that the changes in blood and uterine ILC2s might be associated with abortion in mice.

Prophylactic Effects of Bee Venom Phospholipase A2 in Lipopolysaccharide-Induced Pregnancy Loss

Spontaneous abortion represents a common form of embryonic loss caused by early pregnancy failure. In the present study, we investigated the prophylactic effects of bee venom phospholipase A2 (bvPLA2), a regulatory T cell (Treg) inducer, on a lipopolysaccharide (LPS)-induced abortion mouse model. Fetal loss, including viable implants, the fetal resorption rate, and the fetal weight, were measured after LPS and bvPLA2 treatment. The levels of serum and tissue inflammatory cytokines were determined. To investigate the involvement of the Treg population in bvPLA2-mediated protection against fetal loss, the effect of Treg depletion was evaluated following bvPLA2 and LPS treatment. The results clearly revealed that bvPLA2 can prevent fetal loss accompanied by growth restriction in the remaining viable fetus. When the LPS-induced abortion mice were treated with bvPLA2, Treg cells were significantly increased compared with those in the non-pregnant, PBS, and LPS groups. After LPS injection, the levels of proinflammatory cytokines were markedly increased compared with those in the PBS mouse group, while bvPLA2 treatment showed significantly decreased TNF-α and IFN-γ expression compared with that in the LPS group. The protective effects of bvPLA2 treatment were not detected in Treg-depleted abortion-prone mice. These findings suggest that bvPLA2 has protective effects in the LPS-induced abortion mouse model by regulating Treg populations.

Autoimmune thyroid disease during pregnancy

Understanding of changes in thyroid function and the consequences of thyroid disease during pregnancy has rapidly grown in the past two decades, and revised American Thyroid Association guidelines on this topic were published in 2017. This Review explores the association between thyroid autoimmunity and complications during and after pregnancy. Thyroid autoimmunity refers to the presence of antibodies to thyroperoxidase or thyroglobulin, or thyroid-stimulating hormone receptor antibodies (TRAbs), or a combination of these, and is present in up to 18% of pregnant women. Thyroid antibodies in pregnant women with normal functioning thyroids (ie, euthyroid) have been associated with several complications, including miscarriage and premature delivery. Treatments to improve pregnancy outcomes are being studied. Whether thyroid antibodies are associated with infertility and assisted reproductive technology outcomes is unclear; although, treatment with low doses of levothyroxine, which is usually used to treat hypothyroidism, can be considered in such situations. Additionally, thyroid antibodies have been associated with other neonatal and maternal complications. All these associations require confirmation in larger prospective studies, and their pathogenic mechanisms need to be better understood. Post-partum thyroiditis is substantially more frequent in women who have thyroid antibodies during pregnancy than in those who do not have thyroid antibodies; however, whether treatment can prevent post-partum thyroiditis in women who are or have been antibody positive is unknown. Finally, TRAbs cross the placenta from the mother to the fetus and can cause fetal or neonatal hyperthyroidism. Therefore, women who are positive for TRAbs during pregnancy should be monitored.

Comparing Serum Levels of Th17 and Treg Cytokines in Women with Unexplained Recurrent Spontaneous Abortion and Fertile Women

BACKGROUND

Increased evidences have shown that unexplained recurrent spontaneous abortion (URSA) is associated with inflammatory responses and breakage of immunological autotolerance. Therefore, the balance between Th17 and Treg cells may elucidate the pathophysiology of URSA.

OBJECTIVE

To investigate the serum concentration of regulatory and inflammatory cytokines associated with Treg and Th17 in both normal and URSA females.

METHODS

Forty-six women with URSA and 28 non-pregnant control women with at least one successful pregnancy were included. Serum was obtained from both groups and stored at -7º C. The serum concentrations of IL-17, IL-21, IL-22, IL-10, and TGF-β were quantitatively determined by ELISA.

RESULTS

The levels of IL-17, IL-21, and IL-22 in sera were significantly higher (P<0.001, P=0.01 and P<0.001, respectively) and TGF-β serum concentration was significantly lower (P=0.02) in URSA women compared with normal controls.

CONCLUSION

Our results suggest that enhancement in Th17-associated cytokine levels and reduction in TGF-β may be one of the factors involved in URSA.

Dydrogesterone and the immunology of pregnancy

Progesterone is indispensable for the maintenance of pregnancy, both via its endocrine effects and its role in creating a favorable immunological environment for the fetus. This review focuses on the immunological effects of progesterone. Progestogens have been shown to have very interesting effects on cytokine production and decidual natural killer (NK) cell activity. The orally-administered progestogen, dydrogesterone, has the ability to modulate cytokine production patterns in a manner that could be conducive to successful pregnancy. The adverse effects of progesterone deficiency and the beneficial effects of progesterone supplementation in pregnancy pathologies will be discussed.

Local immunity status in patients with miscarriages and herpetic infection

A study of the endometrium of women with herpetic infection has shown that early miscarriages (under 12 weeks) occurs as activation of cytotoxic natural killer (NK) cells with CD16 + phenotype and a pronounced suppression level of CD56 + cells endometrial type, and late miscarriages (13-22 weeks of gestation) occurs as cell deficit, followed by reduction of all CD8 + cytotoxic lymphocytes, and of CD56 + and CD16 + NK cells.

Antiphosphatidylserine antibodies and reproductive failure

Some cases of reproductive failure with autoimmune background are characterized by the involvement of autoantibodies. This occurs mainly in patients having systemic lupus erythematosus or antiphospholipid syndrome. The autoantibodies associated with reproductive failure include: a) antibodies which directly bind phospholipid (e.g., cardiolipin, phosphatidylserine, phosphatidylethanolamine); b) antiphospholipid Abs which bind the phospholipid via phospholipid-binding glycoproteins such as b2glycoprotein-I, annexin V and prothrombin; c) autoantibodies directed to laminin-I, actin, thromboplastin, the corpus luteum, prolactin, poly (ADP-ribose), thyroglobulin and mitochondrial antibodies of the M5 type. This paper will focus on the association of antiphosphatidylserine autoantibodies and reproductive failure. Future studies are likely to help to identify peptides resembling the epitope specificities associated with the specific clinical manifestations.

Autoantibodies associated with reproductive failure

Autoimmune factors are involved in some of the cases of reproductive failure. These factors entail several autoantibodies, especially in patients having systemic lupus erythematosus (SLE) or the antiphospholipid syndrome (APS). These autoantibodies include mainly antibodies directed to phospholipid such as cardiolipin, phosphatidylserine, phosphatidylethanolamine or phospholipids binding glycoproteins such as b2glycoprotein-I, annexin V, prothrombin and protein-Z. There are also some other autoantibodies directed to laminin-I, thromboplastin, mitochondrial antibodies of the M5 type, corpus luteum, prolactin, poly (ADP-ribose), thyroglobulin and more, which were also found in SLE or APS patients with reproductive failure. Moreover, the presence of additional autoantibodies directed to actin, enolase, cubilin and others, needs further investigation to support a firm association to reproductive failure in women. Future studies are likely to help to determine and expand the number of autoantibodies screened in these patients, as well as by the use of proteomics technology, to determine peptides resembling the epitope specificities associated with the specific clinical manifestations.

Subclinical Hypothyroidism and Thyroid Autoimmunity Are Not Associated With Fecundity, Pregnancy Loss, or Live Birth

CONTEXT

Prior studies examining associations between subclinical hypothyroidism and antithyroid antibodies with early pregnancy loss and live birth suggest mixed results and time to pregnancy (TTP) has not been studied in this patient population.

OBJECTIVE

This study sought to examine associations of prepregnancy TSH concentrations and thyroid autoimmunity with TTP, pregnancy loss, and live birth among women with proven fecundity and a history of pregnancy loss.

DESIGN AND SETTING

This was a prospective cohort study from a large, randomized controlled trial that took place at four medical centers in the United States.

PATIENTS OR OTHER PARTICIPANTS

Healthy women, ages 18-40 y, who were actively attempting to conceive and had one or two prior pregnancy losses and no history of infertility were eligible for the study.

INTERVENTION

There were no interventions.

MAIN OUTCOME MEASURE

TTP, pregnancy loss, and live birth.

RESULTS

Women with TSH ≥ 2.5 mIU/L did not have an increased risk of pregnancy loss (risk ratio, 1.07; 95% confidence interval [CI], 0.81-1.41) or a decrease in live birth rate (risk ratio, 0.97; 95% CI, 0.88-1.07) or TTP (fecundability odds ratio, 1.09; 95% CI, 0.90-1.31) compared with women with TSH <2.5 mIU/L after adjustment for age and body mass index. Similar findings were observed for women with thyroid autoimmunity and after additional adjustment for treatment assignment.

CONCLUSIONS

Among healthy fecund women with a history pregnancy loss, TSH levels ≥ 2.5 mIU/L or the presence of antithyroid antibodies were not associated with fecundity, pregnancy loss, or live birth. Thus, women with subclinical hypothyroidism or thyroid autoimmunity can be reassured that their chances of conceiving and achieving a live birth are likely unaffected by marginal thyroid dysfunction.

The contribution of thyroid autoimmunity to miscarriage in euthyroid women

The presences of antithyroid autoantibodies (ATA), such as thyroid peroxidase-specific antibody and/or thyroglobulin-specific antibody, are considered as the markers of thyroid autoimmunity, which have been found highly associated with pregnancy loss in euthyroid women. Miscarriage is a multifactorial problem that is not rare in women of reproductive age. Increased prevalence of ATA has been reported in women with a history of abortion. High risk of miscarriage has also been found in those with thyroid autoimmunity. In the present study, we used a myriad of correlative and latest papers till March 2016, including randomized clinical trials, case-control and cross sectional studies, to provide a comprehensive review of the literature to investigate the potential role of thyroid autoimmunity in pathogenesis of miscarriage.

Possible Role of HLA-G, LILRB1 and KIR2DL4 Gene Polymorphisms in Spontaneous Miscarriage

The KIR2DL4 receptor and its ligand HLA-G are considered important for fetal-maternal immune tolerance and successful pregnancy. The absence of a particular variant of KIR2DL4 might be a bad prognostic factor for pregnancy outcome. However, it could be compensated by the presence of the respective LILRB1 allele. Therefore, we investigated the KIR2DL4, LILRB1 and HLA-G polymorphisms in 277 couples with spontaneous abortion and 219 control couples by HRM, PCR-SSP and RFLP methods. We found a protective effect of women’s heterozygosity in −716 HLA-G (p = 0.0206) and LILRB1 (p = 0.0131) against spontaneous abortion. Surprisingly, we observed more 9A/10A genotypes of KIR2DL4 gene carriers in the group of male partners from the miscarriage group in comparison to the men from the control group (p = 0.0288). Furthermore, there was no association of women’s KIR2DL4 polymorphism with susceptibility to spontaneous abortion. Multivariate analysis indicated that women’s −716 HLA-G and LILRB1 and men’s KIR2DL4 9A/10A are important in terms of the protection or susceptibility to miscarriage, respectively (p = 0.00968). In conclusion, a woman’s heterozygosity in HLA-G and LILRB1 might be an advantage for a success of reproduction, but the partner’s heterozygosity in 9A/10A KIR2DL4 alleles might not.

RelB activation in anti-inflammatory decidual endothelial cells: a master plan to avoid pregnancy failure?

It is known that excessive inflammation at fetal-maternal interface is a key contributor in a compromised pregnancy. Female genital tract is constantly in contact with microorganisms and several strategies must be adopted to avoid pregnancy failure. Decidual endothelial cells (DECs) lining decidual microvascular vessels are the first cells that interact with pro-inflammatory stimuli released into the environment by microorganisms derived from gestational tissues or systemic circulation. Here, we show that DECs are hypo-responsive to LPS stimulation in terms of IL-6, CXCL8 and CCL2 production. Our results demonstrate that DECs express low levels of TLR4 and are characterized by a strong constitutive activation of the non-canonical NF-κB pathway and a low responsiveness of the canonical pathway to LPS. In conclusion, DECs show a unique hypo-responsive phenotype to the pro-inflammatory stimulus LPS in order to control the inflammatory response at feto-maternal interface.

Prematurity and Low Birth Weight did not Correlate with Anti-Toxoplasma gondii Maternal Serum Profiles--a Brazilian Report

Gestational Toxoplasma gondii infection is considered a major risk factor for miscarriage, prematurity and low birth weight in animals. However, studies focusing on this topic in humans are scarce. The objective of this study is to determine whether anti-Toxoplasma gondii maternal serum profiles correlate prematurity and low birth weight in humans. The study examined 213 pregnant women seen at the High-Risk Pregnancy Hospital de Base, São José do Rio Preto, São Paulo, Brazil. All serological profiles (IgM-/IgG+; IgM-/IgG-; IgM+/IgG+) were determined by ELISA commercial kits. Maternal age, gestational age and weight of the newborn at birth were collected and recorded in the Statement of Live Birth. Prematurity was defined as gestational age <37 weeks and low birth weight ≤ 2499 grams. The t-test was used to compare values (p < 0.05). The mean maternal age was 27.6±6.6 years. Overall, 56.3% (120/213) of the women studied were IgM-/IgG+, 36.2% (77/213) were IgM-/IgG- and 7.5% (16/213) were IgM+/IgG+. The average age of the women with serological profile IgM+/IgG+ (22.3±3.9 years) was different from women with the profile IgM-/IgG+ (27.9±6.7 years, p = 0.0011) and IgM-/IgG- (27.9±6.4 years, p = 0.0012). There was no statistically significant difference between the different serological profiles in relation to prematurity (p = 0.6742) and low birth weight (p = 0.7186). The results showed that prematurity and low birth weight did not correlate with anti-Toxoplasma gondii maternal serum profiles.

Elevated Serum Level of IL-35 Associated with the Maintenance of Maternal-Fetal Immune Tolerance in Normal Pregnancy

Objectives

IL-35 is a novel inhibitory cytokine. In this study, we investigate the serum levels of inhibitory cytokines IL-35, IL-10 and TGF-β in both normal pregnancies and non-pregnant females, and whether IL-35 is associated with the pathogenesis of recurrent spontaneous abortion. We also try to elucidate the relationships of IL-35 with estrogen and alpha-fetoprotein (AFP).

Methods

The levels of IL-35, IL-10, TGF-β, estradiol (E2), unconjugated estriol (uE3) and AFP were analyzed in 120 normal pregnancies, 40 women suffering recurrent spontaneous abortion, 40 postpartum healthy women and 40 non-pregnant women by enzyme-linked immunosorbent assay (ELISA). The correlations between inhibitory cytokines, estrogen and AFP were assessed with the Spearman rank correlation coefficient.

Results

Data are expressed as median and percentiles (Q1, Q3).The level of serum IL-35 in normal pregnancies was significantly higher than that in non-pregnant women [333.6 (59.32, 1391) pg/mL vs. 123.9 (8.763, 471.7) pg/mL; P < 0.001]. A significantly higher level of TGF-β was observed in the first trimester only as compared to non-pregnant women [473.4 (398.0, 580.5) pg/mL vs. 379.7 (311.0, 441.3) pg/mL, P < 0.01]. The difference in serum IL-10 level between pregnant women and non-pregnant women was not significant [8.602 (5.854, 12.89) pg/mL vs. 9.339 (5.691, 12.07) pg/mL; P > 0.05]. The level of serum IL-35 in recurrent spontaneous abortion was significantly lower than that in normal early pregnancy [220.4 (4.951, 702.0) pg/mL vs. 386.5 (64.37, 1355) pg/mL; P < 0.05]. The higher IL-35 level in first trimester pregnant women correlated with E2 (r = 0.3062, P < 0.01) and AFP (r = 0.3179, P < 0.01).

Conclusion

Serum levels of IL-35 increased in normal pregnancy and decreased in recurrent spontaneous abortion. Increased IL-35 correlated with estrogen and AFP levels in early pregnancy. IL-35 is becoming recognized as an active player in the maintenance of a successful pregnancy, but this is not the case for IL-10 or TGF-β.

Gaze palsy, hypogeusia and a probable association with miscarriage of pregnancy--the expanding clinical spectrum of non-opticospinal neuromyelitis optica spectrum disorders: a case report

BACKGROUND

Neuromyelitis optica is characterised by optic neuritis, longitudinally-extensive transverse myelitis and presence of anti-aquaporin-4 antibodies in the serum. However, non-opticospinal central nervous system manifestations have been increasingly recognised. Awareness of the widening clinical spectrum of neuromyelitis optica (unified within the nosology of 'neuromyelitis optica spectrum disorders') is key to earlier diagnosis and appropriate therapy. We report 2 patients to illustrate the varied clinical manifestations of neuromyelitis optica spectrum disorders while postulating an effect of anti-aquaporin-4 antibodies on the miscarriage of pregnancy. This is the first report of horizontal gaze palsy as a presenting symptom of neuromyelitis optica spectrum disorders.

CASE PRESENTATION

Patient 1: A 17-year-old Sri Lankan female presented with hypersomnolence, lateral gaze palsy and loss of taste of 1 week duration. Two years previously she had presented with intractable hiccups and vomiting followed by a brainstem syndrome. Magnetic resonance imaging showed a lesion in the left cerebellum extending into the pons while lesions in bilateral hypothalami and medulla noted 2 years ago had resolved. Autoimmune, vasculitis and infection screens were negative. Anti-aquaporin-4 antibodies were detected in serum. All her symptoms resolved with immunosuppressive therapy. Patient 2: A 47-Year-old Sri Lankan female presented with persistent vomiting lasting over 3 weeks. Three years previously, at 25-weeks of her 4(th) pregnancy, she had presented with quadriparesis and was found to have a longitudinally extensive transverse myelitis from C2 to T2 vertebral levels, which gradually improved following intravenous steroid therapy. Magnetic resonance imaging showed a hyper-intense lesion in the area postrema and longitudinally extensive atrophy of the cord corresponding to her previous myelitis. Autoimmune, vasculitis and infection screens were negative. Anti-aquaporin-4 antibodies were detected in serum. Her vomiting subsided with immunosuppressive therapy. Her second pregnancy had resulted in a first-trimester miscarriage.

CONCLUSION

The clinical spectrum of neuromyelitis optica spectrum disorders has expanded beyond optic neuritis and myelitis to include non-opticospinal syndromes involving the diencephalon, brainstem and cerebrum. Our report highlights the varied central nervous system manifestations of neuromyelitis optica spectrum disorders and miscarriage of pregnancy possibly related to anti-aquaporin-4 antibodies.

Elevated levels of dehydroepiandrosterone as a potential mechanism of dendritic cell impairment during pregnancy

BACKGROUND

This study aimed to test the hypothesis that immune dysfunction and the increased risk of spontaneous abortion in pregnant women with hyperandrogenia (HA) are caused by the reduced tolerogenic potential of dendritic cells (DCs) that results from elevated levels of dehydroepiandrosterone sulfate (DHEAS).

METHODS

The phenotypic and functional properties of monocyte-derived DCs generated from blood monocytes from non-pregnant women, women with a normal pregnancy, or pregnant women with HA, as well as the in vitro effects of DHEAS on DCs in healthy pregnant women were investigated.

RESULTS

In a normal pregnancy, DCs were shown to be immature and are characterized by a reduced number of CD83(+) and CD25(+) DCs, the ability to stimulate type 2 T cell responses and to induce T cell apoptosis. By contrast, DCs from pregnant women with HA had a mature phenotype, were able to stimulate both type 1 (IFN-γ) and type 2 (IL-4) T cell responses, and were characterized by lower B7-H1 expression and cytotoxic activity against CD8(+) T cells. The addition of DHEAS to cultures of DCs from healthy pregnant women induced the maturation of DCs and increased their ability to activate type 1 T cell responses.

CONCLUSION

Our data demonstrated the reduction in the tolerogenic potential of DCs from pregnant women with HA, and revealed new mechanisms involved in the hormonal regulation of DCs mediated by DHEAS.

Maternal subclinical hypothyroidism, thyroid autoimmunity, and the risk of miscarriage: a prospective cohort study

BACKGROUND

Increasing data suggest that subclinical hypothyroidism (SCH) and thyroid autoimmunity (TAI) are associated with adverse pregnancy outcomes, but there are limited data on the association of these conditions in early pregnancy with subsequent miscarriage.

METHODS

In this prospective cohort study, we screened 3315 women at low risk for thyroid dysfunction at four to eight weeks' gestation from iodine-sufficient areas of China between January 2012 and September 2012. Thyrotropin (TSH), free thyroxine (fT4), and the autoantibodies thyroid-peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb) were measured. Based on these results, women were divided into four groups for comparison: euthyroidism (ET), isolated SCH, isolated TAI (positive TPOAb or/and TgAb), and SCH with TAI (SCH+TAI). The SCH group was stratified into two subgroups (SCH 1 and SCH 2) on the basis of the level of TSH (2.5 ≤ TSH < 5.22 or 5.22 ≤ TSH < 10 respectively). Accordingly, the SCH+TAI group was also stratified into two subgroups (SCH+TAI 1 and SCH+TAI 2). The outcome of interest was miscarriage, defined as spontaneous pregnancy loss prior to 20 weeks.

RESULTS

Compared to women with ET, the risk of miscarriage was significantly higher among women with SCH 2 (7.1% vs. 2.2%, aOR 3.40 [CI 1.62-7.15]; p = 0.002), isolated TAI (5.7% vs. 2.2%, aOR 2.71 [CI 1.43-5.12]; p = 0.003), SCH+TAI 1 (10.0% vs. 2.2%, aOR 4.96 [CI 2.76-8.90]; p = 0.000), and SCH+TAI 2 (15.2% vs. 2.2%, aOR 9.56 [CI 3.76-24.28]; p = 0.000). The gestational ages of 110 women at miscarriage were lower among women with subclinical thyroid abnormalities compared to ET (11.13 ± 3.21 weeks with subclinical thyroid abnormalities vs. 9.33 ± 1.71 weeks with ET; p = 0.024). In parallel with the higher TSH levels, there were earlier gestation ages at miscarriage between subgroups of SCH and SCH+TAI (SCH 1 vs. SCH 2: 10.79 ± 1.77 vs. 9.70 ± 1.47 weeks, p = 0.039; SCH+TAI 1 vs. SCH+TAI 2: 9.59 ± 1.97 vs. 8.88 ± 1.24 weeks, p = 0.031).

CONCLUSIONS

Women with SCH and TAI are at an increased risk of miscarriage between four and eight gestational weeks. Women with a combination of SCH and TAI were found to have the highest risk and earlier gestational ages of miscarriage.

Prevention of CpG-induced pregnancy disruption by adoptive transfer of in vitro-induced regulatory T cells

OBJECTIVE

To elucidate the mechanism by which embryo-resorption and preterm birth were enhanced by pathogenic CpG motif and to develop a counter strategy for normal pregnancy outcome.

METHODS

This is an animal model-based study. In pregnant nonobese diabetic (NOD) mice and wild-type (WT) mice in the same strain background, an infection was mimicked by toll-like receptor 9 (TLR9) activation through CpG1826-injection. In vivo inactivation of IL-10 was performed to enhance pregnancy loss. Regulatory T cells induced by FTY720 in vitro from splenic CD4+CD25-Foxp3- cells (iTreg cells) were transferred to improve pregnancy outcomes in NOD mice.

RESULTS

Embryo-resorption and preterm birth were readily induced by CpG1826 in NOD mice, but not in WT mice. However, inactivation of IL-10 using neutralizing antibody injections enhanced pregnancy loss in WT mice exposed to CpG, while adoptive transfer of iTreg cells increased decidual Foxp3+ Treg cells and IL-10+ cell number and rescued pregnancy.

CONCLUSIONS

NOD mice are prone to abortion and preterm birth. This can be attributed to lacking Treg cells and insufficient IL-10 expression. Adoptive transfer of iTreg cells can rescue CpG-mediated pregnancy failure.

The effect of HLA-DRB1 sharing between the couples with recurrent pregnancy loss on the pregnancy outcome after leukocyte therapy

BACKGROUND

Miscarriage is a common phenomenon complicating more than half of pregnancies. Recurrent Pregnancy Loss (RPL) is defined as three or more pregnancies lost before the twentieth week of gestation. It is believed that abnormality in maternal immune reaction to fetus and sharing of HLA antigens might be associated with RPL.

OBJECTIVE

To investigate the effect of HLA-DRB1 sharing between the couples with recurrent pregnancy loss on the pregnancy outcome after leukocyte therapy.

METHODS

Sixty primary RPL women who were immunized and followed after therapy (30 successful and 30 unsuccessful) and their husbands formed the cases of this study. In addition, one hundred healthy women were considered as the controls. HLA-DRB1 genotypes of all the cases and controls were checked by PCR-SSP method.

RESULTS

HLA typing indicated that the prevalence of HLA-DRB1 sharing (defined as at least one allele sharing) between the couples with unsuccessful outcomes was significantly higher compared to those with successful outcomes (63.3% vs. 23.3%, p<0.004). Moreover, HLA DRB1*07:01 allelic group was significantly more frequent in the patients with unsuccessful outcome compared to the controls (18.3% vs. 8%, p<0.04).

CONCLUSION

Our results confirmed the role of HLA sharing in RPL and revealed that HLA-DRB1 typing may be a valuable prognostic factor for the leukocyte therapy outcome.

Adoptive transfer of pregnancy-induced CD4+CD25+ regulatory T cells reverses the increase in abortion rate caused by interleukin 17 in the CBA/JxBALB/c mouse model

STUDY QUESTION

Could adoptive transfer of pregnancy-induced CD4+CD25+ regulatory T cells (Tregs) reverse the increase in abortion rate caused by interleukin 17 (IL-17) in the CBA/J × BALB/c mouse model?

SUMMARY ANSWER

The effects of exogenous IL-17 on increased abortion rate, as well as decreased transforming growth factor (TGF)-β and IL-10 expression, are reversed by a pre-mating transfusion of Tregs in a mouse model of pregnancy.

WHAT IS KNOWN ALREADY

IL-17 is a pro-inflammatory cytokine mainly expressed by T helper 17 cells, and plays a pivotal role in the pathogenesis of endometriosis, miscarriage, preterm labor and pre-eclampsia. The activity of Th17 cells is attenuated by the anti-inflammatory action of Tregs.

STUDY DESIGN, SIZE, DURATION

Fifty microliters of phosphate-buffered saline (PBS) (Group 1,) or recombinant IL-17 (rIL) (10 µg/mouse) supernatant (Group 2) was administered in the vaginal vaults of anesthetized pregnant CBA/J mice on Day 1 of pregnancy. Tregs (2 × 10(5) cells) purified from pregnant CBA/J × BALB/c mice were given i.v. via the tail vein 2 days before mating (Group 3) or on Day 7 of pregnancy (Group 4).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Mice (n = 40) were randomly assigned to one of four experimental groups. The numbers of surviving and reabsorbed fetuses in each group were counted on Day 14 of pregnancy, and the expression of interferon (IFN)-γ, IL-4, TGF-β and IL-10 in the decidual tissue was assessed by real-time RT-PCR and western blotting.

MAIN RESULTS AND THE ROLE OF CHANCE

Normal pregnant CBA/J mice mated with BALB/c males which received transvaginal rIL-17 presented with a significantly increased abortion rate compared with the group which received PBS (27.7 versus 9.9%, respectively; P < 0.05). The transfusion of pregnancy-induced Tregs from 14-day normal pregnant mice 2 days before mating reduced the abortion rate caused by IL-17 (12.5 versus 27.7%, respectively; P < 0.05), while transfusion of Tregs on Day 7 of pregnancy had no effect. Transfusion of Tregs did not affect IFN-γ or IL-4 expression in the decidual tissue at either the mRNA or protein level. Administration of rIL-17 resulted in a decrease in production of TGF-β and IL-10 at both mRNA and protein levels (P < 0.05). Transfusion of Tregs before mating increased TGF-β and IL-10 mRNA and protein levels (P < 0.05), while Tregs transfusion at Day 7 of pregnancy had no effect on TGF-β or IL-10 expression.

LIMITATIONS, REASONS FOR CAUTION

These data derive from only a small number of mice. It is unclear whether the same effects would be seen in humans.

WIDER IMPLICATIONS OF THE FINDINGS

Abnormally elevated expression of IL-17 in the feto-maternal interface may result in miscarriage. Transfer of antigen-specific Tregs before mating takes place may have potential applications in the prevention of recurrent spontaneous abortion.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by a grant from the National Natural Science Foundation of China (81370013, 81000277 and 81300533) and Shandong Provincial Natural Science Foundation, China (ZR2013HQ002). There were no conflicts of interest.

The role of interferons in early pregnancy

The interferons (IFNs) form part of the large family of glycoproteins known as cytokines. They are secreted by host cells as a line of defence against pathogens and certain tumours. IFNs affect cell proliferation and differentiation and also play a very important role in the functioning of the immune system. Miscarriage in both humans has been associated with higher levels of IFN, particularly IFN-γ. However, this cytokine is evidently vital in successful murine pregnancies since it is involved in maintaining the decidual layer in addition to remodelling of the vasculature in the uterus. The effects of IFN on human pregnancies are more difficult to study. Hence, there is still a lot more to be discovered in the hope of reaching a definite conclusion regarding the impact of IFN.

Natural killer cells and regulatory T cells in early pregnancy loss

Survival of the allogeneic embryo in the uterus depends on the maintenance of immune tolerance at the maternal-fetal interface. The pregnant uterus is replete with activated maternal immune cells. How this immune tolerance is acquired and maintained has been a topic of intense investigation. The key immune cells that predominantly populate the pregnant uterus are natural killer (NK) cells. In normal pregnancy, these cells are not killers, but rather provide a microenvironment that is pregnancy compatible and supports healthy placentation. In placental mammals, an array of highly orchestrated immune elements to support successful pregnancy outcome has been incorporated. This includes active cooperation between maternal immune cells, particularly NK cells, and trophoblast cells. This intricate process is required for placentation, immune regulation and to remodel the blood supply to the fetus. During the past decade, various types of maternal immune cells have been thought to be involved in cross-talk with trophoblasts and in programming immune tolerance. Regulatory T cells (Tregs) have attracted a great deal of attention in promoting implantation and immune tolerance beyond implantation. However, what has not been fully addressed is how this immune-trophoblast axis breaks down during adverse pregnancy outcomes, particularly early pregnancy loss, and in response to unscheduled inflammation. Intense research efforts have begun to shed light on the roles of NK cells and Tregs in early pregnancy loss, although much remains to be unraveled in order to fully characterize the mechanisms underlying their detrimental activity. An increased understanding of host-environment interactions that lead to the cytotoxic phenotype of these otherwise pregnancy compatible maternal immune cells is important for prediction, prevention and treatment of pregnancy maladies, particularly recurrent pregnancy loss. In this review, we discuss relevant information from experimental and human models that may explain the pregnancy disrupting roles of these pivotal sentinel cells at the maternal-fetal interface.

Antiphospholipid antibodies among women experiencing fetal loss

The presence of antiphospholipid antibodies (aPLs) is closely associated with thrombotic events and pregnancy complications such as recurrent pregnancy loss, preeclampsia and placental insufficiency. We investigated the presence of aPLs and its frequency among female patients with a history of fetal loss in a Malaysia population. Serum samples were collected from 108 patients who had (1) one or more unexplained deaths of morphologically normal fetuses at or beyond the 22nd week of gestation, or (2) one or more premature births of morphologically normal neonates at or before the 24th week of gestation due to eclampsia or preeclampsia, or recognized features of placental insufficiency, or (3) three or more unexplained, consecutive, spontaneous miscarriages before the 20th week of gestation. Serum was tested for aPLs subtypes: anticardiolipin (aCL), anti-beta-2- glycoprotein I (aβ2GPI), anti-beta-2-glycoprotein I dependent cardiolipin (aβ2GPI dependent CL), anti-phosphatidylcholine (aPC), anti-phosphatidylethanolamine (aPE), anti-phosphatidylinositol (aPI), anti-phosphatidylserine (aPS) and anti-sphingomyeline (aSph) by using the enzyme-linked immunosorbent assay (ELISA) method. The mean age of patients was 30±5. Four patients (3.7%) were found positive for at least one aPLs subtype. Four aPLs subtypes were detected. The most common subtypes was aβ2GPI dependent CL (3.7%), followed by aCL (2.7%), aβ2GPI (0.9%), and aPE(0.9%). In conclusion, frequency of aPLs among women with fetal loss (3.7%) in Malaysia was low with subtype aβ2GPI dependent CL being the most prevalent aPLs.

Serum anti-endometrial antibodies and first trimester pregnancy loss

Serum anti-endometrial antibodies (AEA) have been studied as a marker for endometriosis and implantation failure. We sought to determine if the presence of AEA in the serum of pregnant patients is associated with first trimester pregnancy loss including complete abortion. This is a prospective pilot case control study of 30 patients presenting with first trimester pregnancy loss compared to a control group of 30 first trimester pregnant patients with a normal course for the presence of serum AEA. The control group was selected using propensity matching of patient characteristics. AEA assays were performed by a single operator blinded to clinical status of patients. The mean maternal age in the study and control groups was not statistically significant (26.1 +/- 5.7 vs. 24.2 +/- 4.5 years, p < 0.155). A history of pregnancy loss was not significantly greater in the study group (12/30 = 40.0%) as compared to the control group (8/30 = 26.7%, p < 0.412). In both study and control groups, 40% of the samples tested positive for AEA; therefore, we found no evidence of an association between the presence of AEA and pregnancy loss. These findings in our pilot study suggest that presence of serum AEA does not appear to be a marker for early pregnancy loss.

The expected number of background disease events during mass immunization in China

It is critical to distinguish events that are temporarily associated with, but not caused by, vaccination from those caused by vaccination during mass immunization. We performed a literature search in China National Knowledge Infrastructure and Pubmed databases. The number of coincident events was calculated based on its incidence rate and periods after receipt of a dose of hypothesized vaccine. We included background incidences of Guillain-Barré syndrome, anaphylaxis, seizure, sudden adult death syndrome, sudden cardiac death, spontaneous abortion, and preterm labour or delivery. In a cohort of 10 million individuals, 7.71 cases of Guillain-Barré syndrome would be expected to occur within six weeks of vaccination as coincident background cases. Even for rare events, a large number of events can be expected in a short period because of the large population targeted for immunization. These findings may encourage health authorities to screen the safety of vaccines against unpredictable pathogens.

[Extrathymic differentiation and antigen response of alphabetaT lymphocytes in pregnancy]

We studied reactivity of alphabetaT lymphocytes in CBA pregnant females toward male antigens and the presence of gene rearrangement in T-cells antigen receptor in peripheral lymphoid organs of mice in the case of three breeding variants: CBA x BALB/c (normal allogenic pregnancy), CBA x CBA (syngenetic pregnancy), and CBA x DBA/2 (prone to abortion combination). It was shown that proliferative response of alphabetaT lymphocytes in pregnant CBA females to male spleen cells was the most marked at normal allogenic pregnancy, the least marked at syngenic pregnancy, and was not observed at the combination CBA x DBA/2. In addition, cells ofparaaortic lymphatic nodes (draining uterus) respond to male antigen reliably more effectively than lymphocytes in mesenterial and axillary lymphatic nodes. Simultaneous estimation of recombinase RAG-1, the key enzyme in rearrangement of T-receptor genes, revealed similar principles: predominant activity of recombinase in T lymphocytes in paraaortal lymphatic nodes of CBA pregnant females. This points to the relationship between extrathymic rearrangement of antigen receptor genes and change in the antigen-detecting repertoire of these cells. The possible biological significance of the discovered phenomenon is discussed.

Measuring thyroid peroxidase antibodies on the day nulliparous women present for management of miscarriage: a descriptive cohort study

BACKGROUND

There has been recent evidence suggesting the presence of anti-thyroid peroxidase antibodies (TPOAb) increases the risk of miscarriage, and levothyroxine can rescue miscarriages associated with TPOAb. We propose the most clinically pragmatic cohort to screen for TPOAb are women presenting for management of a missed miscarriage and have never birthed a liveborn. We measured serum TPOAb among nulliparous women presenting for management of miscarriage, and compared levels with women who have had 2 or more livebirths (and never miscarried). Given its potential role in immunomodulation, we also measured Vitamin D levels.

METHODS

We performed a prospective descriptive cohort study at a tertiary hospital (Mercy Hospital for Women, Victoria, Australia). We measured TPOAb and Vitamin D levels in serum obtained from 118 nulliparous women presenting for management of miscarriage, and 162 controls with 2 or more livebirths (and no miscarriages). Controls were selected from a serum biobank prospectively collected in the first trimester at the same hospital.

RESULTS

Nulliparous women with 1 or more miscarriages had higher thyroid peroxidase antibody (TPOAb) levels than those with 2 or more livebirths; TPOAb in miscarriage group was 0.3 mIU/L (interquartile range [IR]: 0.2-0.7) vs 0.2 mIU/L among controls (IR 0.0-0.5; p < 0.0001). We confirmed TPOAb levels were not correlated with serum human chorionic gonadotrophin (hCG) concentrations in either the miscarriage or control groups. In contrast, thyroid stimulating hormone, fT3 and fT4 levels (thyroid hormones) either trended towards a correlation, or were significantly correlated with serum hCG levels in the two groups. Of the entire cohort that was predominantly caucasian, only 12% were Vitamin D sufficient. Low Vitamin D levels were not associated with miscarriage.

CONCLUSIONS

We have confirmed the association between miscarriage and increased TPOAb levels. Furthermore, it appears TPOAb levels in maternal blood are not influenced by serum hCG levels. Therefore, we propose the day nulliparous women present for management for miscarriage is a clinically relevant, and pragmatic time to screen for TPOAb.

Anti-D administration after spontaneous miscarriage for preventing Rhesus alloimmunisation

BACKGROUND

During pregnancy, a Rhesus-negative (Rh-negative) woman may develop antibodies if her fetus is Rh-positive, which can cause fetal morbidity or mortality in following pregnancies, if untreated.

OBJECTIVES

To assess the effects of administering anti-D immunoglobulin (Ig) after spontaneous miscarriage in a Rh-negative woman, with no anti-D antibodies.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 December 2012).

SELECTION CRITERIA

Randomised controlled trials (RCT) in Rh-negative women without antibodies who were given anti-D Ig following spontaneous miscarriage compared with no treatment or placebo treatment following spontaneous miscarriage as control.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and trial quality. Two review authors extracted data and checked it for accuracy.

MAIN RESULTS

We included one RCT, involving 48 women who had a miscarriage between eight to 24 weeks of gestation. Of the 19 women in the treatment group, 14 had therapeutic dilatation & curettage (D&C) and five had spontaneous miscarriage; of the 29 women in the control group, 25 had therapeutic D&C and four had spontaneous miscarriage. The treatment group received 300 µg anti-D Ig intramuscular injection and were compared with a control group who received 1 cc homogenous gamma globulin placebo.This review's primary outcomes (development of a positive Kleihauer Betke test (a test that detects fetal cells in the maternal blood; and development of RhD alloimmunisation in a subsequent pregnancy) were not reported in the included study.Similarly, none of the review's secondary outcomes were reported in the included study: the need for increased surveillance for suspected fetal blood sampling and fetal transfusions in subsequent pregnancies, neonatal morbidity such as neonatal anaemia, jaundice, bilirubin encephalopathy, erythroblastosis, prematurity, hypoglycaemia (low blood sugar) in subsequent pregnancies, maternal adverse events of anti-D administration including anaphylactic reaction and blood-borne infections.The included study did report subsequent Rh-positive pregnancies in three women in the treatment group and six women in the control group. However, due to the small sample size, the study failed to show any difference in maternal sensitisation or development of Rh alloimmunisation in the subsequent pregnancies.

AUTHORS' CONCLUSIONS

There are insufficient data available to evaluate the practice of anti-D administration in an unsensitised Rh-negative mother after spontaneous miscarriage. Thus, until high-quality evidence becomes available, the practice of anti-D Immunoglobulin prophylaxis after spontaneous miscarriage for preventing Rh alloimmunisation cannot be generalised and should be based on the standard practice guidelines of each country.

Infertility and pregnancy loss in euthyroid women with thyroid autoimmunity

Thyroid autoimmunity is the most prevalent autoimmune state that affects up to 5-20% of women during the age of fertility. Prevalence of thyroid autoimmunity is significantly higher among infertile women, especially when the cause of infertility is endometriosis or polycystic ovary syndrome. Presence of thyroid autoimmunity does not interfere with normal embryo implantation and have been observed comparable pregnancy rates after assisted reproduction techniques in patients with or without thyroid autoimmunity. Instead, the risk of early miscarriage is substantially raised with the presence of thyroid autoimmunity, even if there was a condition of euthyroidism before pregnancy. Furthermore the controlled ovarian hyperstimulation, used as preparation for assisted reproduction techniques, can severely impair thyroid function increasing circulating estrogen levels. Systematic screening for thyroid disorders in women with a female cause of infertility is controversial but might be important to detect thyroid autoimmunity before to use assisted reproduction techniques and to follow-up these parameters in these patients after controlled ovarian hyperstimulation and during pregnancy.

Regulatory T cells and reproduction: how do they do it?

Regulatory T cells (Treg cells) identified by expression of Foxp3 play an important role in successful implantation and gestation. Various mechanisms have been proposed to explain their actions, and the more credible and less credible are set out in this review. Induction of Treg cells is believed to occur in response to paternal antigens in seminal plasma at the time of mating, and these Treg cells home to the uterus prior to implantation. Tolerogenic dendritic cells are proposed to play an important role in the generation of Treg cells in the draining lymph nodes and in maintaining Treg activity in the uterus. Recent data indicate that abortion in the CBAxDBA/2 model may be prevented by seminal plasma antigens from DBA/2 and BALB/c males, but H-2(d) restriction suggests that presentation to Treg cells might occur via a novel mechanism. The relevance of findings in mice to human pregnancy problems is also discussed.

Blockage of heme oxygenase-1 abrogates the protective effect of regulatory T cells on murine pregnancy and promotes the maturation of dendritic cells

Regulatory T cells (Treg) play an important role in fetal protection. They expand during normal pregnancy and protect fetal antigens from maternal effector cells. Their effect is associated with the up-regulation of tolerance-associated molecules at the fetal-maternal interface. Among these, Heme Oxygenase-1 (HO-1, coded by Hmox1) is of special importance as its blockage correlates with increased abortion rates and its up-regulation positively affects pregnancy outcome. Here, we aimed to investigate whether the protective effect of Treg is mediated by HO-1 in a mouse model. HO-1 blockage by Zinc Protoporhyrin (ZnPPIX) abrogated the protective effect of Treg transfer. We found that HO-1 is important in maintaining maternal dendritic cells (DCs) in an immature state, which contributes to the expansion of the peripheral Treg population. This brings to light one essential pathway through which Treg mediates the semi-allogeneic fetus tolerance.

Anti-phospholipid induced murine fetal loss: novel protective effect of a peptide targeting the β2 glycoprotein I phospholipid-binding site. Implications for human fetal loss

β2 glycoprotein I (β2GPI)-dependent anti-phospholipid antibodies (aPL) induce thrombosis and affect pregnancy. The CMV-derived synthetic peptide TIFI mimics the PL-binding site of β2GPI and inhibits β2GPI cell-binding in vitro and aPL-mediated thrombosis in vivo. Here we investigated the effect of TIFI on aPL-induced fetal loss in mice. TIFI inhibitory effect on in vitro aPL binding to human trophoblasts was evaluated by indirect immunofluorescence and ELISA. TIFI effect on aPL-induced fetal loss was investigated in pregnant C57BL/6 mice treated with aPL or normal IgG (NHS). Placenta/fetus weight and histology and RNA expression were analyzed. TIFI, but not the control peptide VITT, displayed a dose-dependent inhibition of aPL binding to trophoblasts in vitro. Injection of low doses of aPL at day 0 of pregnancy caused growth retardation and increased fetal loss rate, both significantly reduced by TIFI but not VITT. Consistent with observations in humans, histological analysis showed no evidence of inflammation in this model, as confirmed by the absence of an inflammatory signature in gene expression analysis, which in turn revealed a TIFI-dependent modulation of molecules involved in differentiation and development processes. These findings support the non-inflammatory pathogenic role of aPL and suggest innovative therapeutic approaches to aPL-dependent fetal loss.

Assessment of skewed exposure in case-control studies with pooling

Pooling-based strategies that combine samples from multiple participants for laboratory assays have been proposed for epidemiologic investigations of biomarkers to address issues including cost, efficiency, detection, and when minimal sample volume is available. A modification of the standard logistic regression model has been previously described to allow use with pooled data; however, this model makes assumptions regarding exposure distribution and logit-linearity of risk (i.e., constant odds ratio) that can be violated in practice. We were motivated by a nested case-control study of miscarriage and inflammatory factors with highly skewed distributions to develop a more flexible model for analysis of pooled data. Using characteristics of the gamma distribution and the relation between models of binary outcome conditional on exposure and of exposure conditional on outcome, we use a modified logistic regression to accommodate nonlinearity because of unequal shape parameters in gamma distributed exposure for cases and controls. Using simulations, we compare our approach with existing methods for logistic regression for pooled data considering: (1) constant and dose-dependent effects; (2) gamma and log-normal distributed exposure; (3) effect size; and (4) the proportions of biospecimens pooled. We show that our approach allows estimation of odds ratios that vary with exposure level, yet has minimal loss of efficiency compared with existing approaches when exposure effects are dose-invariant. Our model performed similarly to a maximum likelihood estimation approach in terms of bias and efficiency, and provides an easily implemented approach for estimation with pooled biomarker data when effects may not be constant across exposure.

Presence of antibodies against Coxiella burnetii and risk of spontaneous abortion: a nested case-control study

Background and Aims

Q fever is a bacterial zoonosis caused by infection with Coxiella burnetii. It is well established that Q fever causes fetal loss in small ruminants. The suspicion has been raised that pregnant women may also experience adverse pregnancy outcome when the infection is acquired or reactivated during pregnancy. The purpose of this study was to assess the potential association between serologic markers of infection with C.burnetii and spontaneous abortion.

Methods

A nested case-control study within the Danish National Birth Cohort, a cohort of 100,418 pregnancies recruited from 1996–2002. Women were recruited in first trimester of pregnancy and followed prospectively. Median gestational age at enrolment was 8 weeks (25 and 75 percentiles: 7 weeks; 10 weeks). During pregnancy, a blood sample was collected at gestational week 6–12 and stored in a bio bank. For this study, a case sample of 218 pregnancies was drawn randomly among the pregnancies in the cohort which ended with a miscarriage before 22 gestational weeks, and a reference group of 482 pregnancies was selected in a random fashion among all pregnancies in the cohort. From these pregnancies, serum samples were screened for antibodies against C. burnetii in a commercial enzyme-linked immunosorbent assay (ELISA). Samples that proved IgG or IgM antibody positive were subsequently confirmatory tested by an immunofluorescence (IFA) test.

Results

Among cases, 11 (5%) were C. burnetii positive in ELISA of which one was confirmed in the IFA assay compared to 29 (6%) ELISA positive and 3 IFA confirmed in the random sample.

Conclusions

We found no evidence of a higher prevalence of C.burnetii antibodies in serum samples from women who later miscarried and the present study does not indicate a major association between Q fever infection and spontaneous abortion in humans. Very early first trimester abortions were, however, not included in the study.