Psycho-neuro-cytokine/endocrine pathways in immunoregulation during pregnancy

Sleep Disturbances and Modulations in Inflammation: Implications for Pregnancy Health

When a woman becomes pregnant, there is a vast series of physiological, vascular, and psychological changes. Among the most commonly reported changes are those involving sleep. Pregnant women report that their ability to maintain sleep and acquire continuous refreshing sleep is impaired during the perinatal period as compared to the non-pregnant period. A growing literature supports the hypothesis that disturbed sleep (which comes in many forms) during the perinatal period is associated with an increased risk of adverse maternal, delivery, and infant outcomes. Among the suggested biological pathways linking sleep and adverse outcomes are disturbances in the immune and hormonal systems. The following paper will discuss (1) the various sleep processes that are commonly disturbed during the perinatal period and the methods used to collect sleep data; (2) the evidence linking sleep to adverse outcomes; and (3) how one specific biological pathway, the immune system, likely mediates these associations. The goal of this paper is to clarify the role that sleep disturbance has during pregnancy.

The modulatory role of cytokines IL-4 and IL-17 in the functional activity of phagocytes in diabetic pregnant women

The study investigated the role of cytokines IL-4 and IL-17 in the modulation of the functional activity of mononuclear phagocytes in diabetic pregnant women with hyperglycemia. Sixty pregnant women were assigned to the following groups: nondiabetic (ND), mild gestational hyperglycemia (MGH), gestational diabetes mellitus (GDM), or type 2 diabetes mellitus (DM2). The functional activity of phagocytes from maternal blood, cord blood, and colostrum was assessed by determining their superoxide release, phagocytosis, microbicidal activity, and intracellular Ca²⁺ release. Irrespective of glycemic status, colostrum and blood cells treated with IL-4 and IL-17 increased superoxide release in the presence of enteropathogenic Escherichia coli (EPEC). The highest phagocytosis rate was observed in cells from the DM2 group treated with IL-4. In all the groups, phagocytes from colostrum, maternal blood, and cord blood exhibited higher microbicidal activity against EPEC when treated with cytokines. IL-17 increased intracellular Ca²⁺ release by colostrum phagocytes in diabetic groups. The results indicate that the IL-4 and IL-17 modulate the functional activity of phagocytes in the maternal blood, cord blood, and colostrum of diabetic mother. The natural immunity resulting from the interaction between the cells and cytokines tested may be an alternative procedure to improve the prognosis of maternal and newborn infections.

Disturbed sleep and inflammatory cytokines in depressed and nondepressed pregnant women: an exploratory analysis of pregnancy outcomes

OBJECTIVE

Disturbed sleep and depression are potential risk factors for pregnancy complications. Both conditions are known to dysregulate biological pathways responsible for maintaining homeostatic balance and pregnancy health. Depression during pregnancy is associated with poor sleep. Thus, we explored whether disturbed sleep was associated with inflammatory cytokines and risk for adverse pregnancy outcomes, as well as whether depression augmented the sleep-cytokine relationship, thereby additively contributing to risk for adverse outcomes.

METHODS

Interview-assessed sleep and plasma cytokine concentrations were evaluated in a cohort of depressed and nondepressed pregnant women (n = 168) at 20 and 30 weeks' gestation. Outcomes evaluated included preterm birth, birth weight, and peripartum events.

RESULTS

Among depressed women, short sleep duration (<7 hours) was associated with higher interleukin (IL)-8 across time (β = 0.506, p = .001), poor sleep efficiency (<85%) was associated with higher IL-6 (β = 0.205, p = .006), and daytime naps were associated with higher tumor necrosis factor α (β = 0.105, p = .024). Aspects of poor sleep were associated with having a lower weight baby (p values <.053). Among depressed women, interferon-γ increased risk for preterm birth (odds ratio = 1.175, p = .032). Trends for IL-6 and higher birth weight (β = 105.2, p = .085), interferon-γ and lower birth weight (β = -19.92, p < .069), and increased IL-8 and babies weighing less than 4000 grams (odds ratio = 0.72, p < .083) were observed.

CONCLUSIONS

Although speculative, disturbed sleep may disrupt normal immune processes and contribute to adverse pregnancy outcomes. Exploratory analyses indicate that depression modifies these relationships.

Interventions (other than pharmacological, psychosocial or psychological) for treating antenatal depression

BACKGROUND

A meta-analysis of 21 studies suggests the mean prevalence rate for depression across the antenatal period is 10.7%, ranging from 7.4% in the first trimester to a high of 12.8% in the second trimester. Due to maternal treatment preferences and potential concerns about fetal and infant health outcomes, diverse non-pharmacological treatment options are needed.

OBJECTIVES

To assess the effect of interventions other than pharmacological, psychosocial, or psychological interventions compared with usual antepartum care in the treatment of antenatal depression.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 January 2013), scanned secondary references and contacted experts in the field to identify other published or unpublished trials.

SELECTION CRITERIA

All published and unpublished randomised controlled trials of acceptable quality evaluating non-pharmacological/psychosocial/psychological interventions to treat antenatal depression.

DATA COLLECTION AND ANALYSIS

Both review authors participated in the evaluation of methodological quality and data extraction. Results are presented using risk ratio (RR) for categorical data and mean difference (MD) for continuous data.

MAIN RESULTS

Six trials were included involving 402 women from the United States, Switzerland, and Taiwan. For most comparisons a single trial contributed data and there were few statistically significant differences between control and intervention groups.In a trial with 38 women maternal massage compared with non-specific acupuncture (control group) did not significantly decrease the number of women with clinical depression or depressive symptomatology immediately post-treatment (risk ratio (RR) 0.80, 95% confidence interval (CI) 0.25 to 2.53; mean difference (MD) -2.30, 95% CI -6.51 to 1.91 respectively). In another trial with 88 women there was no difference in treatment response or depression remission rates in women receiving maternal massage compared with those receiving non-specific acupuncture (RR 1.33, 95% CI 0.82 to 2.18; RR 1.14, 95% CI 0.59 to 2.19 respectively).In a trial with 35 women acupuncture specifically treating symptoms of depression, compared with non-specific acupuncture, did not significantly decrease the number of women with clinical depression or depressive symptomatology immediately post-treatment (RR 0.47, 95% CI 0.11 to 2.13; MD -3.00, 95% CI -8.10 to 2.10). However, women who received depression-specific acupuncture were more likely to respond to treatment compared with those receiving non-specific acupuncture (RR 1.68, 95% CI 1.06 to 2.66).In a trial with 149 women, maternal massage by a woman's significant other, compared with standard care, significantly decreased the number of women with depressive symptomatology immediately post-treatment (MD -6.70, 95% CI -9.77 to -3.63). Further, women receiving bright light therapy had a significantly greater change in their mean depression scores over the five weeks of treatment than those receiving a dim light placebo (one trial, n = 27; MD -4.80, 95% CI -8.39 to -1.21). However, they were not more likely to have a treatment response or experience a higher remission rate (RR 1.79, 95% CI 0.90 to 3.56; RR 1.89, 95% CI 0.81 to 4.42).Lastly, two trials examined the treatment effect of omega-3 oils. Women receiving omega-3 had a significantly lower mean depression score following eight weeks of treatment than those receiving a placebo (one trial, n = 33; MD -4.70, 95% CI -7.82 to -1.58). Conversely, in a smaller trial (21 women) there was no significant difference in the change in mean depression scores for women receiving omega-3 and those receiving a placebo (MD 0.36, 95% CI -0.17 to 0.89), and women who received omega-3 were no more likely to respond to treatment (RR 2.26, 95% CI 0.78 to 6.49) or have higher remission rates (RR 2.12, 95% CI 0.51 to 8.84). Women in the placebo group were just as likely to report a side effect as those in the omega-3 group (RR 1.12, 95% CI 0.56 to 2.27).

AUTHORS' CONCLUSIONS

The evidence is inconclusive to allow us to make any recommendations for depression-specific acupuncture, maternal massage, bright light therapy, and omega-3 fatty acids for the treatment of antenatal depression. The included trials were too small with non-generalisable samples, to make any recommendations.

Live and non-live pregnancy outcomes among women with depression and anxiety: a population-based study

BACKGROUND

Women taking antidepressant or anti-anxiety medications during early pregnancy have high risks of non-live pregnancy outcomes, although the contribution of the underlying illnesses to these risks remains unclear. We examined the impacts of antenatal depression and anxiety and of commonly prescribed treatments on the risks of non-live pregnancy outcomes.

METHODS

We identified all pregnancies and their outcome (live birth, perinatal death, miscarriage or termination) among women aged 15-45 years between 1990 and 2009 from a large primary care database in the United Kingdom. Women were grouped according to whether they had no history of depression and anxiety, a diagnosis of such illness prior to pregnancy, illness during pregnancy and illness during pregnancy with use of medication (stratified by medication type). Multinomial logistic regression models were used to compare risks of non-live outcomes among these groups, adjusting for major socio-demographic and lifestyle characteristics.

RESULTS

Among 512,574 pregnancies in 331,414 women, those with antenatal drug exposure showed the greatest increased risks for all non-live pregnancy outcomes, relative to those with no history of depression or anxiety, although women with prior (but not currently medicated) illness also showed modest increased risks. Compared with un-medicated antenatal morbidity, there was weak evidence of an excess risk in women taking tricyclic antidepressants, and stronger evidence for other medications.

CONCLUSIONS

Women with depression or anxiety have higher risks of miscarriage, perinatal death and decisions to terminate a pregnancy if prescribed psychotropic medication during early pregnancy than if not. Although underlying disease severity could also play a role, avoiding or reducing use of these drugs during early pregnancy may be advisable.

The effect of human placenta cytotrophoblast cells on the maturation and T cell stimulating ability of dendritic cells in vitro

The success of pregnancy depends upon regulatory mechanisms that allow the fetus to survive and develop to term in the uterus, despite maternal immune cells' awareness of paternal alloantigens. At least some of these specific mechanisms are mediated by the effect of fetal trophoblast cells. In the present study we examine the effect of human placental cytotrophoblast cells (CTCs) on the maturation of dendritic cells (DCs) in vitro. For that purpose, CTCs were isolated from samples of placentae at 5-11 weeks of gestation and co-cultured with peripheral blood monocytes under conditions inducing DC maturation. CTC were shown to alter the morphology, phenotype and functional properties of DCs. As a result, a significant portion of cells acquire fibroblast-like morphology and some of the cells retain the expression of CD14. DCs matured in the presence of CTCs do not differ from usual DCs in terms of CD80, CD83 and CD86 expression, as well as the ability to induce allogenic lymphocytes proliferation. However, CTCs reduce significantly the ability of DCs to stimulate interferon-γ production and the loss of CD62L by T cells. The results obtained indicate that DCs may be involved in pregnancy-associated changes of cytokine production and T cell migration.

How valuable is measurement of peripheral blood natural killer cells at the time of abortion?

PROBLEM

Increased peripheral blood natural killer (NK) cells are associated to immune-mediated abortion, but their diagnostic value when measured at the time of miscarriage is unknown.

METHOD OF STUDY

In women with therapeutic (A = 79) or elective (C = 34) pregnancy termination, the NK-cell percentage was measured before and 5 days after curettage. Additionally, immune-mediated lesions (scored 0-3) and CD56(+) and CD16(+) decidual NKs (scored 1-3) were detected on the abortion material.

RESULTS

Aborters differed from controls in histological scores (P = 0.000) and in NK percentage (>12%) only in the measurement 5 days after the operation (P = 0.038). In comparison to histological lesions, NK measurement was found to have sensitivity 70%, specificity 73.68%, positive prognostic value 89.39% and negative prognostic value 43.75%.

CONCLUSION

An Increased NK-cell percentage 5 days after the pregnancy termination could be a marker of immune aetiology of miscarriage, as the probability of an aborter with NK >12% to have an immune-mediated abortion is almost 90%.

Maternal acceptance of the fetus: true human tolerance

Induction and maintenance of immunologic tolerance in humans remains a desirable but elusive goal. Therefore, understanding the physiologic mechanisms of regulation of immune responses is highly clinically relevant for immune-mediated diseases (e.g., autoimmunity and asthma/allergy) and for cell and organ transplantation. Acceptance of the fetus, which expresses paternally inherited alloantigens, by the mother during pregnancy is a unique example of how the immune system reshapes a destructive alloimmune response to a state of tolerance. Understanding the complex mechanisms of fetomaternal tolerance has important implications for developing novel strategies to induce immunologic tolerance in humans in general and for prevention of spontaneous abortion in at-risk populations in particular.

Sleep disruption during pregnancy: how does it influence serum cytokines?

Women report their sleep to be disrupted during pregnancy. Sleep deprivation has been linked to elevations in pro-inflammatory cytokine levels. No information currently addresses the sleep-immune relationship during pregnancy. This study explores the relationship between subjectively reported sleep variables and circulating serum cytokine levels. Pregnant women (n=35; mean age=31.0+/-3.7 years) seen once a trimester completed sleep questionnaires, gave blood and recorded their sleep on a sleep diary at home for 2 weeks. Nonpregnant women (n=43; mean age=28.2+/-5.2 years) underwent the same protocol once. Subjective sleep variables were compared to serum cytokine levels for IL-4, -6, -10 and TNF-alpha as well as C-reactive protein (CRP) determined by ELISA. Nonparametric analyses and linear regression were performed to explore relationships between the sleep and immune variables. Pregnant women subjectively reported their sleep to be worse than in the nonpregnant group. Serum cytokine levels differed between the two groups and varied by trimester. As anticipated, IL-10 was significantly higher in all trimesters; however CRP, an indicator of systemic inflammation, was higher in all trimesters compared to the nonpregnant sample. Subjectively reported sleep disruption was associated with increases in TNF-alpha in the pregnant sample and CRP in the nonpregnant sample. These data confirm that disrupted sleep experienced during pregnancy, as well as during the nonpregnant state, is related to increases in inflammatory markers. Future exploration of these relationships should include functional assessments of immunity as well as polysomnographically recorded sleep.

Cancer and pregnancy share similar mechanisms of immunological escape

BACKGROUND

Despite the fact that trophoblasts and cancer are both immunogenic, they are able to escape from host immunosurveillance, and the precise mechanisms involved in this process are surprisingly similar in both situations.

METHODS

A literature review of studies on immunological changes occurring during normal pregnancy and cancer was performed.

RESULTS

Loss or downregulation of classical HLA antigens as well as the presence of non-classical HLA-G molecules, a Th2 cytokine activity shift, secretion of immunosuppressive factors and blocking antibodies and finally induction of apoptosis in immunocytes seem to be the most effective mechanisms of immunological escape in pregnancy and cancer.

CONCLUSIONS

The process of immunological escape in cancer and pregnancy is based on similar mechanisms.

Th1/Th2 cytokines balance--yin and yang of reproductive immunology

For years conception of Th2 overbalance during pregnancy has been a paradigm for immunology of reproduction, while Th1 activity has been presented as unwanted component. Studies concerning Th1/Th2 balance in physiological and complicated pregnancy have been reviewed. Th1 activity during early peri-implantation period, premature and term labour not only accompanies but even predominates over Th2 activity. Th1 activity plays important role in promotion of Th2 response, regulation of placentation process, defense against infections and initiation of delivery. Together with Th2 activity it is necessary component of immunological reactions during pregnancy, both activities being inseparable like yin and yang. So paradigm of "Th1-Th2 cooperation" is much closer to reality than "Th2 phenomenon".

Lack of the appropriate natural killer cell inhibitory receptors in women with spontaneous abortion

Previous studies have revealed that women with unexplained recurrent spontaneous abortions have a limited repertoire of inhibitory KI receptors (inhKIRs) and that the inhKIRs they possess do not have specificity for the human leukocyte antigen (HLA)-Cw molecules that would be expressed on trophoblast. We sought to confirm these findings by direct definition of maternal inhKIR and trophoblastic HLA-Cw allotypes on the placental material of spontaneously missed pregnancies. The study included 30 women undergoing vacuum uterine curettage for first-trimester missed pregnancy (group A; n = 15) or for elective termination of normal pregnancy (group C, n = 15). DNA extracted from isolated decidual and trophoblastic cells was used for molecular detection of maternal inhKIRs (2DL1, 2DL2, 2DL3) and fetal HLA-Cw alleles, respectively. The results revealed that in the group of women who experienced abortion, 60% did not have the full repertoire of three inhKIRs (group A vs group C; p = 0.006); that in five of 15 patients (none in the controls), no epitope matching existed between maternal inhKIRs and trophoblastic HLA-Cw alleles (group A vs group C; p = 0.01); and that more cases were found with limited epitope matching (less than three inhKIRs with specificity for fetal HLA-Cw alleles). The results provide additional evidence that in some cases of spontaneous abortions, the women lack the appropriate inhKIRs to interact with the HLA-Cw molecules on trophoblasts and to deliver signals to inhibit natural killer cell activation and protect the embryo.

Dietary Echinacea purpurea during murine pregnancy: effect on maternal hemopoiesis and fetal growth

BACKGROUND

The medicinal benefits of Echinacea sp. plants in several disease conditions, including insect bites, respiratory ailments, and even cancer and AIDS, have been touted for decades. Echinacea sp.-based phytoceuticals are among the top selling herbals in the Western marketplace today. However, evidence is very scant concerning the effects of using Echinacea species herbals during pregnancy. While available data indicates that fetal malformations do not occur during pregnancy in humans consuming this herb, there are no formal studies aimed at assessing the possibility that consuming Echinacea herbals may promote spontaneous abortions, thereby reducing the number of live births upon which to assess the presence or absence of malformations.

OBJECTIVES

We undertook a study in which pregnant mice were fed daily Echinacea purpurea from pregnancy onset until gestational days 10, 11, 12, 13, and 14.

METHODS

Maternal spleen and bone marrow were taken for enumeration of cells in each of five separate hemopoietic lineages/organ, and fetal status was recorded.

RESULTS

The data indicate that the significant, pregnancy-induced elevation in splenic lymphocytes and nucleated erythroid cells was all but eliminated in those females which consumed E. purpurea daily throughout their pregnancy. Moreover, consuming E. purpurea during pregnancy reduced the number of viable fetuses.

CONCLUSIONS

The data may be extrapolated to suggest that in humans, abstention from consuming Echinacea products during the early/mid stages of pregnancy, may be prudent.

Altered immunophenotypic parameters in infertile women. Possible role of herpes viremia

PROBLEM

Purpose of this study was to reveal any alteration in peripheral blood lymphocytic concentrations of a large cohort of infertile women and to investigate the possible role of herpes viremia in the peripheral immunostimulation.

METHOD OF STUDY

The immunophenotypic characteristics and the presence of herpes viruses DNA in the peripheral blood of 168 infertile women were studied.

RESULTS

Peripheral CD56+/CD16+ natural killer (NK) cell concentration, CD56+/CD16- NK cell concentration, white blood cell (WBC) concentration and lymphocyte concentration were statistically correlated to herpes viremia. Epstein-Barr virus (EBV) viremia is related with a limited reduction of CD56+/CD16- cell levels in the peripheral blood of infertile women with regard to the rest of herpes viruses. High T-lymphocyte concentration, CD4+ T-cell concentration and CD8+ T-cell concentration was observed in women positive for three different kinds of herpes viruses (triple viremia) in the peripheral blood.

CONCLUSIONS

Assuming that all women under study remained asymptomatic, these data suggest that subclinical herpesvirus viremia may be an important cause of peripheral immunostimulation in women with a history of infertility.

Uterine NK Cells Mediate Inflammation-Induced Fetal Demise in IL-10-Null Mice

Specialized NK cells are recruited in high numbers to the mammalian embryo implantation sites, yet remain pregnancy compatible. It is not well understood whether uterine NK (uNK) cells become adversely activated and mediate fetal demise, a common complication of early pregnancy. In this study we show that mating of IL-10(-/-) mice resulted in fetal resorption or intrauterine growth restriction in response to very low doses of LPS. Pregnancy in congenic wild-type mice was normal even at 10-fold higher LPS doses. Fetal resorption in IL-10(-/-) mice was associated with a significant increase in uNK cell cytotoxic activation and invasion into the placenta. Depletion of uNK cells, TNF-alpha neutralization, or IL-10 administration rescued pregnancy in LPS-treated IL-10(-/-) animals. Our results identify an immune mechanism of fetal demise involving IL-10 deficiency, NK cells, and inflammation. These results may provide insight into adverse pregnancy outcomes in humans.

Therapy with dendritic cells influences the spontaneous resorption rate in the CBA/J x DBA/2J mouse model

PROBLEM

DBA/2J-mated CBA/J female mice are prone to a high incidence of fetal abortions. This fetal wastage can be dramatically reduced by immunizing the female mice with BALB/c, but not with DBA/2J spleen cells during early gestation. Nevertheless, the underlying mechanisms remain to be elucidated. Recently, dendritic cells (DC) have been described at the feto-maternal interface in the human uterus. In this work, we studied the effect of adoptive transfer of DC on the maintenance of pregnancy in the CBA/J x DBA/2J model.

METHODS

Bone marrow-derived DC were generated from virgin female CBA/J mice (6-8 weeks old). CBA/J females were inoculated with DC twice before mating. Four different experimental groups were included: (i) no treatment control, (ii) mice injected with culture medium [granulocyte-macrophage colony-stimulating factor (GM-CSF)], (iii) immunized with DC and (iv) immunized with paternal DBA/2J antigens lisate-pulsed DC, n = 5.

RESULTS

The control abortion rate was 23.8%, and with GM-CSF alone was 17.6%. Following inoculation of syngeneic DC abortion rates were reduced to 2.2%, but protection was short-lived. Abortion rates with DC pulsed with DBA/2J antigens was 5%. Serum of interleukin (IL)-6 levels were lower in the latter two groups up to the time of abortion. The kinetics of immunoglobulin G asymmetric antibodies synthesis was modified, but there was no correlation between asymmetric antibodies production and the lowering of abortions rates.

CONCLUSION

Syngeneic DC prevented abortions and this was linked to a decrease in IL-6 levels, but not with levels of asymmetric antibodies.

Role of a KIR/HLA-C allorecognition system in pregnancy

Decidual natural killer (NK) cells are thought to play a significant role in the allorecognition mechanisms during pregnancy. Through their activating and inhibitory receptors they may recognize selectively class I HLA alleles expressed on invading trophoblast and provide self-signals to control NK responses, thus regulating the maternal immune response at the fetomatenal interface. Killer immunoglobulin-like receptors (KIR) constitute one of the families of class I MHC receptors which are expressed on NK cells. Their repertoire includes both activating and inhibitory receptors, most of which recognize specific epitopes on HLA-C molecules and can either activate NK cell responses or abort activating signals and inhibit NK cell functions. Since KIRs are expressed on decidual NK cells and the HLA-C molecules that they recognize are also expressed on invading trophoblast, KIR receptors may play a regulatory role in pregnancy by interacting with their trophoblastic HLA-C counterparts and providing trophoblast damage evading signals (KIR/HLA-C allorecognition system). Our hypothesis that the KIR/HLA-C system might be ineffective in some unsuccessful pregnancies, has been investigated in women with unexplained spontaneous abortions. Our results suggest that a limited maternal repertoire of inhibiting KIRs (inhKIRs) and/or lack of maternal inhKIR-fetal HLA-C epitope matching may predispose to miscarriage.

Psychosocial predictors of successful delivery after unexplained recurrent spontaneous abortions: a cohort study

OBJECTIVE

To examine psychosocial predictors of successful pregnancy after recurrent spontaneous abortions (RSA).

METHOD

We administered two waves of semi-structured interview and self-report questionnaire battery to a consecutive series of 46 couples who had had two RSAs (baseline before third pregnancy, and immediately after third pregnancy was ascertained), and followed them through their third pregnancy.

RESULTS

Of the 46 couples, four miscarried for karyotypal abnormalities and six without any known cause. When the latter six were compared with the remaining 36 women, they reported less social support satisfaction, a more stable attribution for the causes of past abortions, and more depressed mood in the preceding year. Taken altogether, this psychosocial model was able to predict 93% of the pregnancy outcomes correctly.

CONCLUSION

Psychosocial variables (depression, attribution and social support) are robust predictors of the prospective pregnancy and suggest possible points of intervention in couples with RSA.

The Effect of Valacyclovir Treatment on Natural Killer Cells of Infertile Women

PROBLEM

The aim of this study was to investigate the effect of valacyclovir treatment on natural killer (NK) cell concentration in the peripheral blood of infertile women.

METHOD OF STUDY

Peripheral blood NK cell concentration of 104 non-pregnant women with a history of infertility was determined by flow cytometry. The controls were 14 fertile non-pregnant women. A cohort of 42 out of 104 women--whose NK cell levels were 175/microL or higher--was prospectively studied for the presence of HSV-1, 2, VZV, cytomegalovirus, HHV-6, HHV-7 and HHV-8 DNA in the peripheral blood and was orally administered valacyclovir (open label study).

RESULTS

Herpes virus DNA was detected in 64.3% of the 42 women examined. Prior to valacyclovir treatment mean NK cell concentration in herpes-negative group was statistically higher from control group but lower from herpes positive group (P = 0.0007, ANOVA). Following valacyclovir treatment the mean NK cell concentration was statistically decreased in all studied women (P = 0.000453), in herpes-negative (P = 0.01622) and in herpes positive group (P = 0.0056). Sufficient decrease was observed in 31 (73.8%) of 42 women who received the drug.

CONCLUSIONS

Valacyclovir treatment is associated with a decrease of NK cell levels in most of the women with a history of infertility.

T-helper 2-cytokine levels in women with threatened abortion

OBJECTIVE

Considering that successful embryo development has been immunologically attributed to a T-helper 2 phenomenon and that threatened abortion is a very frequent but pathogenetically not well-defined clinical entity, our purpose was to investigate serum levels of the main T-helper 2-type cytokines during the evolution of this condition.

STUDY DESIGN

Three T-helper 2-type cytokines (interleukin-6 (IL-6), interleukin-10 (IL-10), interleukin-13 (IL-13)) were measured by an enzyme-linked immunosorbent assay (ELISA) in serum of 12 women with threatened abortion both at hospital admission and discharge time. Fourteen women with missed abortion, 14 normal pregnant women and 14 normal non-pregnant women represent study control groups.

RESULTS

Serum concentrations of the selected T-helper 2-type cytokines showed no significant differences in women with threatened abortion with those of normal pregnant and non-pregnant women, whereas showed significantly lower values in women with missed abortion.

CONCLUSION

Our data (a) confirm the concept that first-trimester normal pregnancy is a T-helper 2 phenomenon, (b) show that threatened abortion, when T-helper 2-biased, may tend to a positive evolution of the condition, (c) display that interleukin-10, particularly, may represent a useful diagnostic and prognostic marker for predicting the normal continuance of the pregnancy in threatened abortion, (d) confirm the existence of a T-helper 2-type pattern deficiency in missed abortion, and finally (e) may open the way to new T-helper 2-biased immune therapies in case of difficult first-trimester pregnancies.

1α,25-dihydroxy-vitamin-D3 as new immunotherapy in treatment of recurrent spontaneous abortion

Recurrent spontaneous abortion (RSA) is serious health problem affecting 2-5% of reproducing couples worldwide. It has long been suspected that nearly 80% of the unexplained RSAs are due to immunologic causes. Although the major tissue confronting the mother's immune system is the placental villous trophoblast, the immunological risk to the developing embryo is not great until the time of implantation. In addition, trophoblast is not sensible to lysis by NK cells, TNF-alpha or macrophages, but may be killed by lymphokine activated NK cells (LAK) and may undergo apoptosis in response to TNF-alpha and/or IFN-gamma in vitro. The two most commonly used treatments for RSA are intravenous immunoglobulin (IVIg) and alloimmunization with partner's leukocytes (LIT). We promote vitamin D3 as new immunomodulatory agent in treatment of RSA. Different mechanisms have been proposed to account for the immunosuppressive effect of 1alpha, 25-dihydroxy-vitamin-D3 (VD3). Portion of the VD3 activity involves the downregulation of IL-2, IFN-gamma and TNF-alpha genes transcription. Because immunomodulatory effects of VD3 are very similar to IL-10 effects, acting of VD3 in immunotherapy of RSA syndrome, preeclamptic and eclamptic pregnancy, as well as PIH syndrome, is very reasonable. We propose using of VD3 as immunotherapy or adjuvant therapy in combination with classic immunotherapies of endangered pregnancies.

Natural killer (NK) cell receptors' repertoire in couples with recurrent spontaneous abortions

PROBLEM

Natural killer (NK) cell receptors (NKRs) have been suggested to protect trophoblast, but their function at the fetomaternal interface remains unknown. To investigate if the outcome of pregnancy depends on women's NKRs, we studied the NKR repertoire in couples with recurrent spontaneous abortions (RSA).

METHODS

Twenty-six childless couples with > or = 2 abortions, characterized by alloimmune abnormalities, and 26 control couples were genotyped for five killer immunoglobulin-like receptors (KIR) and two CD94/NKG receptors, known to have as ligands human leukocyte antigen (HLA) class I molecules with trophoblastic expression: inhibitory 2DL1,2,3 and activating 2DS1,4 KIRs, inhibitory NKG2A and activating NKG2C. Detected repertoires of women and partners were compared between the two groups.

RESULTS

Less aborters than controls were found to have all three inhibitory KIRs (30.77% versus 69.23%, P = 0.01), some of them had only one inhibitory KIR (19.23% versus 3.85%, P = 0.08) and most of them were lacking inhibitory KIRs possessed by their husbands (57.69% versus 15.38%, P = 0.001).

CONCLUSIONS

Women with alloimmune abortions have a limited inhibiting KIR repertoire and such miscarriages may occur because trophoblastic HLA class I molecules are recognized by decidual NK cells lacking the appropriate inhibitory KIRs.

The role of pro- and anti-apoptotic molecular interactions in embryonic maldevelopment

PROBLEM

Pregnancy loss and the occurrence of inborn structural anomalies are often preceded by excessive apoptosis in targeted embryonic and extraembryonic tissues. Apoptogenic stimuli activate both death and survival, signaling cascades consisting of molecules acting as activators and effectors, or negative regulators of apoptosis. The interplay between these cascades determines whether the cell which is exposed to an apoptogenic stimulus dies or survives. This review summarizes the functioning of pro- and anti-apoptotic molecules in embryos responding to various teratogens. The effect of potentiation of the maternal immune system on these molecules is also discussed.

METHODS OF STUDY

The data on the functioning of various pro- and anti-apoptotic molecules in embryos exposed to various developmental toxicants, and embryos developing in a diabetic environment are reviewed. Techniques such as the TUNEL method, DNA fragmentation assay, electromobility shift assay (EMSA), fluorometric assay, immunohistochemistry, Western blot, In situ hybridization, have been used in our studies to detect apoptosis, and evaluate the functioning of molecules such as TNFalpha, caspases, NF-kappaB and IkappaB, p53, and bcl-2 in different embryonic and extraembryonic tissues.

RESULTS

Our and other data summarized in this review have demonstrated that the doses of developmental toxicants required to induce pregnancy loss and gross structural anomalies induce excessive apoptosis shortly after treatment. Depending on the intensity and type of targeted tissues, this apoptosis was accompanied by alterations in the activity of the molecules which act as activators and effectors (e.g. caspase 3, caspase 8, caspase 2, p53) or negative regulators (bcl-2, NF-kappaB) of apoptosis. Maternal immunopotentiation, which decreases the level of induced and spontaneous pregnancy loss and the incidence and severity of teratogen-induced structural anomalies has been shown to modulate the expression of these molecules both in embryonic tissues and at the feto-maternal interface.

CONCLUSIONS

The data presented in this review suggest that molecules such as TNFalpha, caspase 3, caspase 8, NF-kappaB, p53 and bcl-2, which are involved in the regulation of apoptosis, may also be involved in determining the sensitivity of the embryo to developmental toxicants. Maternal immunopotentiation may modulate the functioning of these molecules.

Personality, social support, coping and emotional distress after repeated spontaneous abortions

Systematic investigations on the emotional impacts of repeated spontaneous abortions have been few. We mounted a prospective study of a cohort of couples who had experienced two consecutive first trimester spontaneous abortions and for whom no clearly identifiable causes were found. The present report is based on the first part of the study and examines: (1) emotional distress reported by the miscarrying women at six months (median, range 1-12 months) after two abortions; and (2) psychosocial predictors influencing such distress. The mean score of the women on the Symptom Checklist 90-Revised--one of the most popular self-report scales for psychopathology--was 0.38, whereas that for the general population is reported to be 0.26 (the higher the score, the more psychopathology). Fourteen percent of the cohort scored above the cutoff point for mental disorders screening. Factors examined and found non-influential upon the level of emotional distress include: the maternal age; whether the last pregnancy was planned and wished for or not; and coping styles of the women after the abortions. Control by the husbands over the marital relationship and neurotic personality traits of the women increased the emotional distress, whereas the social support the women perceive decreased it. These findings suggest that martial and social support are important in determining the level of psychiatric morbidity after repeated abortions.

Cytokine secretion by decidual lymphocytes in transient hypertension of pregnancy and pre-eclampsia

BACKGROUND

Transient hypertension (TH) and preeclampsia (PE) are believed to have different pathophysiology. However, 15-25% of pregnant women initially diagnosed as having TH develop PE. To clarify the immuno-pathogenetical connections between the two syndromes, we studied the pattern of T helper cell (Th)1/Th2 cytokine balance disturbances existing inside maternal decidua in normal pregnancy (NP) and pregnancies complicated with TH and PE.

METHODS

Third-trimester decidual tissue was obtained by curettage of uterine cavity during elective caesarean sections in NP (n = 11), TH (n = 17) and PE (n = 21) patients. Cell suspensions were prepared by an electromechanical dispersal method and centrifugated using a standard gradient sedimentation technique. Isolated lymphocytes were placed in medium (RPMI 1640, 10% fetal calf serum, L-glutamine, penicillin, streptomycin) and cultured for 72 h with or without mitogen phytohaemaglutinine (PHA). The enzyme-linked immunosorbent assay method was used for estimation of interleukin (IL)-2, IL-4, IL-6, IL-10, IL-12 and interferon-gamma (IFN-gamma) in culture supernatant.

STATISTICAL ANALYSIS

The Kruskal-Wallis and the Mann-Whitney U tests were used (p < 0.05).

RESULTS

Both spontaneous and PHA-stimulated secretion of Th2-type cytokines IL-6 and IL-10 was decreased in PE patients compared with TH and NP patients. The concentration of Th1-type cytokine IFN-gamma was increased in patients suffering both from TH and PE.

CONCLUSION

On the base of decidual cytokine secretion, both PE and TH are syndromes of local Th1/Th2 cytokine balance disturbances as compared with NP, and TH seems to be an intermediate step to PE.

Cyclooxygenase is involved in the effects of progesterone-induced blocking factor on the production of interleukin 12

OBJECTIVE

Immunologic effects of progesterone are mediated by the progesterone-induced blocking factor. Progesterone-induced blocking factor inhibits natural killer cytotoxic activity and arachidonic acid release from mononuclear cells. The relationship between increased prostaglandin synthesis and increased cytotoxic activity of the lymphocytes is still unclear; therefore we investigated the effect of progesterone-induced blocking factor-neutralizing antibody, as well as simultaneous indomethacin treatment, on interleukin 12 production.

STUDY DESIGN

Pregnancy lymphocytes were treated with anti-progesterone-induced blocking factor antibody or lipopolysaccharide as a positive control in the presence or absence of indomethacin. Interleukin 12 production by peripheral blood mononuclear cells was detected by immunocytochemical examination. The 2-tailed Student t test was used for statistical evaluation.

RESULTS

Neutralization of progesterone-induced blocking factor, as well as lipopolysaccharide treatment, resulted in an increased expression of interleukin 12 that was corrected by simultaneous indomethacin treatment.

CONCLUSION

Progesterone-induced blocking factor reduces the expression of interleukin 12 via the inhibition of arachidonic acid metabolism. This results in lowered cytotoxic natural killer activity, which favors a normal pregnancy outcome.

Mitogen-induced cytokine responses of maternal peripheral blood lymphocytes indicate a differential Th-type bias in normal pregnancy and pregnancy failure

PROBLEM

Profiles of Th1- and Th2-type cytokines were studied in women with a history of successful pregnancy and in women with a history of unexplained recurrent spontaneous abortions (RSA) with the objective of elucidating Th1- and Th2-type bias in normal pregnancy and pregnancy failure.

METHOD OF STUDY

Peripheral blood mononuclear cells (PBMCs) from 54 women with a history of normal pregnancy and 23 women with a history of unexplained RSA, obtained at delivery or on the day of abortion, respectively, were stimulated with phytohemagglutinin (PHA), followed by the estimation of four Th2 cytokines and four Th1 cytokines.

RESULTS

Significantly greater levels of Th2 cytokines were produced by the normal group than by the RSA group. On the other hand, significantly higher levels of Th1 cytokines were produced by the RSA group than by the normal pregnancy group.

CONCLUSIONS

These data support the concept that unexplained recurrent spontaneous abortion is associated with an increase in Th1-type reactivity, while Th2 dominance is a feature of successful pregnancy.

Murine T cell determination of pregnancy outcome

At the fetomaternal interface, maternal effector cells come in intimate contact with fetal trophoblast cells which express paternal antigens. Failure of fetal trophoblast cells to activate maternal Th1 immune responses has been attributed in part to the absence of classical Class I and Class II major histocompatibilty complex (MHC) antigen expression and elaboration of factors which reduce TcR expression and shift any immune responses which may occur to Th2. Classical TcR alphabeta(+) T cells have not been found to be able to respond to trophoblasts. Recently, TcR gammadelta(+) T cells have been characterized in the low-abortion-rate pregnant C57Bl/10 mouse decidua, and the Vgamma1(+) subset may be able to respond to trophoblasts in a non-MHC-dependent manner. Trophoblast-recognizing T cells with Vgamma1 receptors are also present in the decidua of CBA/J mice pregnant by DBA/2, an abortion-prone mating combination. To test the role of the Vgamma1 subset of decidual gammadelta T cells in abortion-prone pregnancies, we altered this subset by injecting monoclonal anti-Vgamma1.1 antibody on gestation day 5.5, 1 day after implantation. This reduced detectability of a Vgammadelta subset producing TNF-alpha and reduced the abortion rate. Anti-Vgamma2, which reacts with a similar proportion of decidual gammadelta T cells as anti-Vgamma1.1, failed to prevent abortions. Vdelta6.3(+) cells are prominent at the fetomaternal interface, and anti-Vdelta6 antibody injected on day 5.5 prevented abortions. TGF-beta2(+) gammadelta cells first appear on day 8.5 of pregnancy; anti-Vgamma1.1 antibody injection on day 8.5 depleted these cells and boosted abortions; anti-Vdelta6.3 given on day 8.5 boosted abortions to the same level. These results suggest that two populations of Vgamma1.1(+)delta6.3(+) T cells may arise in the decidua: an early population that is Th1, abortogenic, and present during the time of implantation, and a Th2/3 cell subset that is present in the decidua later during pregnancy and which is pregnancy-protective.

An innate view of human pregnancy

Our understanding of the immunology of pregnancy has been dominated by the fetal allograft model and by changes in the maternal-specific immune system. Here, Gavin Sacks and colleagues draw attention to substantial and contrasting changes in the maternal innate system and hypothesize that its function and that of monocytes in particular, has a central role in the maternal-fetal relationship.

Why did your mother reject you? Immunogenetic determinants of the response to environmental selective pressure expressed at the uterine level

PROBLEM

Maternal "rejection" of the implanted conceptus is considered to account for a significant proportion of miscarriages (abortions) in both humans and animals. Our understanding of mechanisms has been limited, and hence, explanations for nonrejection have remained largely speculative. Losses, when they occur, could represent either random accidental failure of protective mechanisms or a more purposeful discrimination.

METHOD OF STUDY

An analysis of the most recent data.

RESULTS AND CONCLUSIONS

The embryo is most akin to a parasite, and pregnancy is most akin to a host-parasite interaction. If one excludes chromosome abnormalities in the embryo as a cause of death, activation of coagulation mechanisms, leading to vasculitis affecting the maternal blood supply to the implanted embryo, appears to represent a major loss-causing mechanisms--a form of ischemic autoamputation. Proinflammatory T-helper (Th) 1-type cytokines trigger this process via upregulation of a novel prothrombinase, fgl2. Th2/3 cytokines, such as interleukin (IL)-4, IL-10, and transforming growth factor (TGF)-beta 2, may antagonize the processes involved. Cytokine balance is determined by the genetics of the mother, which regulate her response to stress; endotoxin (LPS); and paternal antigens, selectively expressed on the trophoblast of the embryo, via imprinting. Based on studies in abortion-prone mice, where immunity to paternal alloantigens prevents loss, three distinct gene products in the embryo are proposed to determine the cytokine response to maternal lymphomyeloid cells in the uterus.

How might pregnancy immunize against breast cancer?

PROBLEM

This study investigated how pregnancy might protect against breast cancer.

METHOD OF STUDY

A critical review of the literature was done.

RESULTS/CONCLUSIONS

Support for an active role in pregnancy immunizing against breast cancer comes from case studies demonstrating a reciprocal correlation between pregnancy and breast cancer as well as recent experiments supporting the fetal antigen hypothesis that confirms the presence of a tumor-specific antigen, MUC1, on both fetal and breast cancer tissues. Multiparous women also generate anti-MUC1 major histocompatibility complex-restricted cytotoxic T cell cytolytic activity against MUC1-bearing tumor cell lines. Careful investigation of the fetal antigen hypothesis and tolerogenic mechanisms may lead to effective vaccination protocols against breast cancer and other cancers.

Clinical trial of immunostimulation with a biological response modifier in unexplained recurrent spontaneous abortion patients

We determined clinically whether a killed streptococcal preparation (KSP), a biological response modifier, is as effective as paternal lymphocyte immunotherapy for unexplained recurrent pregnancy abortion (RSA) therapy. The success rate of adverse pregnancy in the study group of 23 RSA cases, who were administered low doses of KSP before and during early pregnancy, was statistically compared with that in a control group of 205 women who received paternal lymphocyte immunotherapy. The association of natural killer (NK) cell activity in the peripheral blood with pregnancy outcome was also assessed. The success rate in the study group was 73.9% (17/23), compared to 75.1% (154/ 205) observed for the controls (not significant). Most of the successful cases exhibited low levels of NK cell activity in the peripheral blood. Immunotherapy with low doses of KSP is as effective as that with paternal lymphocytes, providing a simple and safe alternative therapy for unexplained RSA. Suppression of NK cell activity by some immunoregulatory mechanism was also found to have potential benefit in terms of a successful pregnancy outcome.

Low serum M-CSF levels are associated with unexplained recurrent abortion

PROBLEM

The purpose of this study was to determine whether the serum macrophage-colony stimulating factor (M-CSF) level is associated with early pregnancy loss in unexplained recurrent spontaneous abortion (RSA) patients.

METHOD

We therefore compared preconceptional serum M-CSF levels between unexplained RSA patients and controls. The former comprised 44 bed-rest therapy patients and 43 intradermal immunization (IDI) patients receiving paternal lymphocyte therapy, who had experienced two and three or more consecutive first-trimester pregnancy losses, respectively. The controls were 46 healthy non-pregnant women. We also prospectively studied the association between M-CSF levels during pregnancy and adverse pregnancy outcomes. Sera from a total of 31 pregnant women, including 16 of the bed-rest therapy group and 15 of the IDI therapy group, were collected at the 4th, 6th, and 8th gestational weeks and were measured for M-CSF levels, using the enzyme-linked immunoadsorbent assay (ELISA) method established by Hanamura et al.

RESULTS

Serum M-CSF levels were significantly lower in the non-pregnant RSA patients (460.0 +/- 185.6 U/ml; mean +/- SD) than in the control group (726.5 +/- 134.0 U/ml) and also were lower at the 8th, but not the 4th or 6th gestational week in those patients of both the bed-rest and IDI therapy groups whose outcome was pregnancy failure.

CONCLUSION

Thus a low level of serum M-CSF was found to be associated with unexplained recurrent pregnancy loss in both the preconceptional and conceptional phases. These results raise the possibility that M-CSF may play an important role in the maintenance of pregnancy and that it can be used as a parameter for determining individuals at risk.

Changes in T, B, and NK lymphocyte subsets during and after normal pregnancy

PROBLEM

Pregnancy affects the maternal immune system and the clinical course of maternal diseases. Here we report the changes in the detailed lymphocyte subsets of helper T cells, suppressor T cells, CD5+ B cells, T cell receptor (TCR) alpha beta-positive T cells (T alpha beta cells), TCR alpha beta-negative T cell (T gamma delta cells), and other during and after pregnancy through to one year postpartum, and discuss the significance of the changes.

METHOD

The absolute numbers of helper T cells, suppressor T cells, cytotoxic T cells, TCR alpha beta-negative T cells (T gamma delta cells), CD5- B cells, CD5+ B cells, and NK cell subsets were examined by two-color flow cytometry in peripheral blood from 51 healthy non-pregnant women, 106 healthy pregnant women, and 148 healthy postpartum women.

RESULTS

In early pregnancy, the numbers of suppressor T cells and NK cells with strong cytotoxicity (NK+3 cells) increased, and the number of cytotoxic T cells decreased. In late pregnancy, the helper T cell and NK+3 cell numbers decreased. T alpha beta, CD5- B and CD5+ B cells decreased during pregnancy. After delivery, helper T cells and cytotoxic T cells increased from 1 to 4 months postpartum, and suppressor T cells increased at 7 months postpartum. TCR alpha beta-negative T cells increased at 4 to 10 months postpartum. Both CD5- and CD5+ B cells decreased further at 1 month postpartum, but CD5+ B cells increased markedly at 7 to 10 months postpartum.

CONCLUSIONS

These data indicate that 1) early increases of suppressor T cells and NK+3 cells during pregnancy may be related to the mechanism to accept or reject the fetus in early pregnancy, respectively; 2) late decreases of helper T cells and NK+3 cells may be related to the maintenance of pregnancy: 3) postpartum increases of helper T cells, cytotoxic T cells, TCR alpha beta-negative T cells (T gamma delta cells), and CD5+ B cells may be related to the postpartum aggravation of autoimmune diseases; and 4) the immunological effects of pregnancy remains until about 1 year after delivery.