Intravenous immunoglobulin treatment in women with recurrent abortions: increased cytokine levels and reduced Th1/Th2 lymphocyte ratio in peripheral blood

Autoimmune thyroid disease and ovarian hypofunction: a review of literature

Thyroid hormones(THs) are essential for the proper functioning of the ovaries, and multiple studies have shown that thyroid abnormalities, especially during adolescence and reproductive age, can lead to lifelong ovarian dysfunction. Autoimmune thyroid disease (AITD), one of the most common organ specific autoimmune diseases, is mainly mediated by cellular autoimmune reactions, and has strong inflammatory infiltration and immune active cells, including chemokines and cytokines, which are important components of ovarian aging. This suggests that autoimmune and inflammatory molecular processes may play a role in the emergence of ovarian dysfunction. The purpose of this review is to summarize recent in vivo and in vitro evidence of a complex relationship between AITD and ovarian dysfunction. AITD is closely related to the decline of ovarian function from the perspective of antibody, cytokine, oxidative stress, and genetic factors. Finally, some of the currently known treatments for AITD and hypo ovarian disease are summarized.

Intravenous Immunoglobulins as Immunomodulators in Autoimmune Diseases and Reproductive Medicine

Intravenous administration of immunoglobulins has been routinely used for more than 60 years in clinical practice, developed initially as replacement therapy in immunodeficiency disorders. Today, the use of intravenous immunoglobulins (IVIGs) is embedded in the modern algorithms for the management of a few diseases, while in most cases, their application is off-label and thus different from their registered therapeutic indications according to the summary of product characteristics. In this review, we present the state-of-the-art use of IVIGs in various autoimmune conditions and immune-mediated disorders associated with reproductive failure, as approved therapy, based on indications or off-label. IVIGs are often an alternative to other treatments, and the administration of IVIGs continues to expand as data accumulate. Additionally, new insights into the pathophysiology of immune-mediated disorders have been gained. Therefore, the need for immunomodulation has increased, where IVIG therapy represents an option for stimulating, inhibiting and regulating various immune processes.

Intravenous immunoglobulin treatment in women with four or more recurrent pregnancy losses: A double-blind, randomised, placebo-controlled trial

BACKGROUND

There is no effective treatment for women with unexplained recurrent pregnancy loss (RPL). We aimed to investigate whether treatment with a high dose of intravenous immunoglobulin (IVIG) in early pregnancy can improve pregnancy outcomes in women with unexplained RPL.

METHODS

In a double-blind, randomised, placebo-controlled trial, women with primary RPL of unexplained aetiology received 400 mg/kg of IVIG daily or placebo for five consecutive days starting at 4-6 weeks of gestation. They had experienced four or more miscarriages except biochemical pregnancy loss and at least one miscarriage of normal chromosome karyotype. The primary outcome was ongoing pregnancy rate at 22 weeks of gestation, and the live birth rate was the secondary outcome. We analysed all women receiving the study drug (intention-to-treat, ITT) and women except those who miscarried due to fetal chromosome abnormality (modified-ITT). This study is registered with ClinicalTrials.gov number, NCT02184741.

FINDINGS

From June 3, 2014 to Jan 29, 2020, 102 women were randomly assigned to receive IVIG (n = 53) or placebo (n = 49). Three women were excluded; therefore 50 women received IVIG and 49 women received placebo in the ITT population. The ongoing pregnancy rate at 22 weeks of gestation (31/50 [62·0%] vs. 17/49 [34·7%]; odds ratio [OR] 3·07, 95% CI 1·35-6·97; p = 0·009) and the live birth rate (29/50 [58·0%] vs. 17/49 [34·7%]; OR 2·60, 95% CI 1·15-5·86; p = 0·03) in the IVIG group were higher than those in the placebo group in the ITT population. The ongoing pregnancy rate at 22 weeks of gestation (OR 6·27, 95% CI 2·21-17·78; p < 0·001) and the live birth rate (OR 4·85, 95% CI 1·74-13·49; p = 0·003) significantly increased in women who received IVIG at 4-5 weeks of gestation as compared with placebo, but these increases were not evident in women who received IVIG at 6 weeks of gestation. Four newborns in the IVIG group and none in the placebo group had congenital anomalies (p = 0·28).

INTERPRETATION

A high dose of IVIG in very early pregnancy improved pregnancy outcome in women with four or more RPLs of unexplained aetiology.

FUNDING

The Japan Blood Products Organization.

Inherent maternal type 2 immunity: Consequences for maternal and offspring health

An inherent elevation in type 2 immunity is a feature of maternal and offspring immune systems. This has diverse implications for maternal and offspring biology including influencing success of pregnancy, offspring immune development and maternal and offspring ability to control infection and diseases such as allergies. In this review we provide a broad insight into how this immunological feature of pregnancy and early life impacts both maternal and offspring biology. We also suggest how understanding of this axis of immune influence is and may be utilised to improve maternal and offspring health.

Thyroid Autoimmunity in Adverse Fertility and Pregnancy Outcomes: Timing of Assisted Reproductive Technology in AITD Women

Thyroid autoimmunity (TAI) is prevalent in women of live-birthing age and has independently been associated with complications of fertility and pregnancy, in the case of spontaneous conception or after assisted reproductive technology (ART) treatment. However, it remains challenging to identify causation between infertility and TAI, even interventional trials looking at the impact of levothyroxine (LT4) treatment on fertility and pregnancy outcomes due to differences among study results which related to small scales, impropriate study designs, enrollment criteria of infertility cause and titer/hormone concentration measurements. Furthermore, many questions remain unsettled in ART management in AITD infertile women attempt pregnancy. Therefore, further observational and interventional trials are needed more comprehensive multiple-center, double blinded, and randomized.

Is there a Role of Intravenous Immunoglobulin in Immunologic Recurrent Pregnancy Loss?

Recurrent pregnancy loss (RPL) commonly refers to three or more miscarriages that occur before 20 weeks of pregnancy. The immunological cause of RPL could be either an auto- or alloimmune-related event or both. Because of the discovery of immunological abnormalities in RPL patients in clinical practice, several immunomodulatory therapies were introduced to maintain the immune balance at the maternal-fetal interface. Intravenous immunoglobulin (IVIg) is one of the immunomodulators. In recent years, several studies have analyzed the therapeutic effect of IVIg on RPL patients with antiphospholipid syndrome (APS) or unexplained RPL. However, their results are controversial. IVIg can be used in RPL patients with APS who have previously failed in other treatments. It is recommended that IVIg infusion could be considered used before conception in RPL patients who have cellular immune abnormalities such as increased natural killer (NK) cell counts, NK cell cytotoxicity, or increased T helper (Th)1/Th2 ratio, depending on the cut-off values of each hospital. The aim of this review was to summarize the mechanisms, efficacy, pharmacokinetics, and side effects associated with passive immunization using IVIg in immunologic RPL, according to the literature published in recent years. We hope that more obstetricians will be able to understand the timing and indication of IVIg properly in immunologic RPL patients and effectively enhance pregnancy outcomes for mothers and neonates.

Harmful and beneficial effects of inflammatory response on reproduction: sterile and pathogen-associated inflammation

In reproduction, inflammatory processes play important roles in the development of many pregnancy complications such as preterm labor/birth, recurrent pregnancy loss, recurrent implantation failure, and preeclampsia. Inflammation can be initiated by both microbial and non-microbial causes. Bacterial infection in the feto-maternal interface and uterus can provoke preterm labor/birth, miscarriage, and chronic endometritis. By contrast, inflammation without infection, or 'sterile inflammation,' can also lead to many kinds of complications, such as preterm labor/birth, miscarriage, or preeclampsia. Aberrant inflammation is facilitated by immune cells such as macrophages, dendritic cells, natural killer cells, and invariant natural killer T cells. In addition, cytokines, chemokines, and several kinds of inflammatory mediators are involved. On the other hand, appropriate inflammation is required for a successful offspring during the progression of the entire pregnancy. Herein, we discuss the relation between pregnancy and inflammation with immunological alterations. Understanding the role of inflammation in complications during pregnancy may establish new perspectives of the progress of normal pregnancy as well as treatments during pregnancy complications.

Maternal Obesity and the Uterine Immune Cell Landscape: The Shaping Role of Inflammation

Inflammation is often equated to the physiological response to injury or infection. Inflammatory responses defined by cytokine storms control cellular mechanisms that can either resolve quickly (i.e., acute inflammation) or remain prolonged and unabated (i.e., chronic inflammation). Perhaps less well-appreciated is the importance of inflammatory processes central to healthy pregnancy, including implantation, early stages of placentation, and parturition. Pregnancy juxtaposed with disease can lead to the perpetuation of aberrant inflammation that likely contributes to or potentiates maternal morbidity and poor fetal outcome. Maternal obesity, a prevalent condition within women of reproductive age, associates with increased risk of developing multiple pregnancy disorders. Importantly, chronic low-grade inflammation is thought to underlie the development of obesity-related obstetric and perinatal complications. While diverse subsets of uterine immune cells play central roles in initiating and maintaining healthy pregnancy, uterine leukocyte dysfunction as a result of maternal obesity may underpin the development of pregnancy disorders. In this review we discuss the current knowledge related to the impact of maternal obesity and obesity-associated inflammation on uterine immune cell function, utero-placental establishment, and pregnancy health.

A Mother-to-Child Transmission Study in Nigeria: The Impact of Maternal HIV Infection and HAART on Plasma Immunoglobulins, Cytokine Profiles and Infant Outcome

Prevention of mother-to-child transmission (PMTCT) of HIV with highly active antiretroviral therapy (HARRT) allows the HIV⁺ pregnant mothers to have vaginal delivery and breastfeed. Here we investigated the maternal plasma immunoglobulin, cytokine secretion and the outcome of the exposed infants among the HIV⁺ HAART treated pregnant women in Nigeria. In this study, different plasma immunoglobulins and cytokines were measured in the HIV⁺ HAART treated pregnant mothers. Pooled culture supernatants of B and T lymphocytes showed lower levels of IFN-γ, IL-10 and IL-4. There were lower IFN-γ and IL-10 secretions at 1st trimester; however, IL-10 continued to be lower throughout 2nd and 3rd trimesters. TNF-α secretion significantly decreased as pregnancy progressed to term. There were high plasma IgG and low IgM in the HIV⁺ HAART treated pregnant women. Plasma IgG was high during 1st and 3rd trimesters. After one year of follow up, all the exposed children were seronegative for HIV-1 and HIV-2. Vaginal delivery and breastfeeding among HIV⁺ HAART treated mothers have shown to be safe. The use of HAART by the infected mothers and the use of septrin and niverapin by the exposed infants prevented mother to-child transmission of HIV.

Mother-fetus immunogenetic dialogue as a factor of progeny immune system development

Despite the advances in medicine, about 4 million children under the age of 6 months die annually around the world due to infection, which is 450 deaths per hour (UNISEF, 2009). The degree of development of the immune system of children born in time is determined by many factors, including the immunogenetic similarity or difference of mother and fetus organisms, which, in turn, is due to the genotypes of mating pairs, as well as the selection of surrogate mothers duringin vitrofertilization. From our review of the literature, it follows that immunogenetic interactions of mother and fetus organisms, which occur at all stages of pre- and postnatal development, have a signifcant effect on the resistance of offspring to infections and allergens. Before implantation, the mother’s immune responses are formed under the influence of semen fluid antigens, leukocytes and cytokines, as well as under the influence of the genes of the major histocompatibility complex, which are expressed in embryos at the stage of two cells. After implantation, transplacental transfer of immunoglobulins and immunocompetent cells becomes of immunomodulating importance. It is important to emphasize that, although substances with a high molecular weight usually do not pass through the placenta, this rule does not apply to immunoglobulin G (IgG), which, with a molecular weight of about 160 kDa, overcomes the transplacental barrier due to binding to the fetal Fc receptor. The level of IgG in newborns usually correlates with the level of maternal antibodies. During the period of natural feeding, the immune protection of newborns is provided by the mechanisms of innate immunity and the factors of humoral immunity of mothers. It has been shown that immunoglobulins from the milk of many animal species are transferred through the neonatal intestinal epithelium to the blood. Since breast milk contains large amounts of various immunoactive components, including proteins, cytokines, hormones, immunoglobulins, exosomes containing micro-RNA, and viable immune cells, the immunomodulating effects of breast milk persist even after elimination of maternal immunoglobulins from the blood of the offspring, up to maturation. Analysis of a large body of experimental data shows that the study of mechanisms of “motherfetus” and “mother-newborn” interactions are the basis of a knowledge base needed to fnd means of life-long directed modulation of the descendants’ immune status.

Modulatory effect of intravenous immunoglobulin on Th17/Treg cell balance in women with unexplained recurrent spontaneous abortion

Recurrent spontaneous abortion (RSA) is a growing problem worldwide. In a majority of cases, the cause remains unknown but there is increasing evidence that immunologic factors play an important role. Intravenous immunoglobulin (IVIg) therapy has been proposed to have immune modulatory effects and therefore been applicable for the treatment of patients with RSA. Although its efficacy is still controversial, several recent studies suggest that IVIg treatment may improve pregnancy outcomes. CD4⁺ T cells and their related cytokines play an important role in maternal-fetal immune regulation, and an imbalance of Th17/Treg cell ratio has been proposed as a cause for RSA. We review the scientific evidence supporting a modulatory effect of IVIg on Th17/Treg cell balance and discuss the potential mechanisms how IVIg might enhance Treg cells function. We propose that correction of Th17/Treg cell dysregulation could be one of the mechanisms that can explain the positive therapeutic effects of IVIg therapy. Consequently, selecting patients with abnormal Th17/Treg cell ratios could increase the success of IVIg therapy.

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.

Effect of Intravenous immunoglobulin on Th1 and Th2 lymphocytes and improvement of pregnancy outcome in recurrent pregnancy loss (RPL)

BACKGROUND

Women with elevated natural killer (NK) cell frequency and function during pregnancy, suffer from recurrent pregnancy loss (RPL). In the present study, the possible effect of intravenous immunoglobulin (IVIG) administration on Th1 and Th2 cell frequency, cytokine secretion, and expression of transcription factors is compared between RPL patients and control group.

MATERIALS AND METHODS

Totally, 44 women with a history of RPL (32 women as treated group and 12 as control group) were enrolled in the study. The frequency of Th1 and Th2 lymphocytes, the expression of transcription factors related to these cells and the serum levels of associated cytokines were assessed by flowcytometry, real-time PCR and ELISA, respectively. All, assessments were performed both before and after treatment with IVIG.

RESULTS

A significant reduction in Th1 lymphocyte frequency, transcription factor expression and cytokine levels were observed in IVIG-treated group, while all the above parameters indicated a significant increase for Th2 lymphocytes. Th1/Th2 ratio decreased significantly (p value<0.0001) at the end of treatment and 28 out of 32 (87.5%) women in IVIG-treated group had live birth in comparison with 5 out of 12 (41.6%) in untreated group.

CONCLUSION

IVIG administration proves to be an efficient therapeutic strategy which is able to enhance the success rate of pregnancy through a shift in Th2 responses. Furthermore, IVIG presents efficacy for the treatment of reproduction failures especially in subjects with immune cell abnormalities and increased NK cell level and function.

Intravenous immunoglobulin G in women with reproductive failure: The Korean Society for Reproductive Immunology practice guidelines

The task force of the Korean Society for Reproductive Immunology recommends intravenous immunoglobulin G treatment in women with reproductive failure, including recurrent pregnancy loss and/or repeated implantation failure, who show cellular immune factors such as abnormal natural killer cell levels, natural killer cell cytotoxicity, and/or type 1 T helper immunity.

Regulation of the Anti-Inflammatory Cytokines Interleukin-4 and Interleukin-10 during Pregnancy

Inflammation mediated by both innate and adaptive immune cells is necessary for several important processes during pregnancy. Pro-inflammatory immune cell activation plays a critical role in embryo implantation, placentation, and parturition; however dysregulation of these cells can lead to detrimental pregnancy outcomes including spontaneous abortion, fetal growth restriction, maternal pathology including hypertensive disorders, or fetal and maternal death. The resolution of inflammation plays an important role throughout pregnancy and is largely mediated by immune cells that produce interleukin (IL)-4 and IL-10. The temporal and spatial aspects of reducing inflammation during pregnancy represent a complex process that if not functioning optimally can lead to persistent inflammation and pregnancy complications. In this review, we examine how immune cells that produce IL-4 and IL-10 are regulated throughout pregnancy as well as the effects that reduced IL-4 and IL-10 signaling has on fetal and maternal physiology.

Comparative analysis of NK cell subsets in menstrual and peripheral blood of patients with unexplained recurrent spontaneous abortion and fertile subjects

Natural killer (NK) cells play a fundamental role in maintaining pregnancy. Based on the availability and non-invasive method of collection of menstrual blood (MB), here we investigated for the first time a comparative analysis of NK cell subsets in MB and peripheral blood (PB) of women with recurrent spontaneous abortion (RSA) and fertile women. PB and MB of healthy fertile (n=15) and RSA women (n=15) were sampled simultaneously on the second day of the menstrual cycle. Proportions of CD56+CD3-CD16+/-, CD56+CD3-CCR7+/-, and CD56+CD3-CD45RO+/- cells were analyzed using flow cytometry. In the MB of both groups, proportions of CD16+ and CD45RO- NK cells were significantly lower than in the PB. In parallel, CD56+CD16+CCR7- and CCR7+ cells were present in significantly smaller amounts in MB than in PB. However, the amounts of CD56+CD16-CCR7- and CCR7+ cells were greater in MB. In comparison to the fertile group, the percentage of MB CD45RO+ NK cells was significantly lower and frequencies of PB CD16-, CD45RO- and CD56+CD16+CCR7+ subsets were significantly higher in RSA patients. Different subsets of NK cells are differentially distributed in MB in comparison with PB in women with RSA and fertile subjects. Population differences of NK cell subsets in RSA patients and normal controls were more clearly reflected at the systemic level.

The relationship between polymorphisms in the promoter region of Tim-3 and unexplained recurrent spontaneous abortion in Han Chinese women

BACKGROUND

Recurrent spontaneous abortion (RSA) refers to 2 or more consecutive pregnancy losses, and RSA with unknown causes is called unexplained recurrent spontaneous abortion (URSA). Tim-3, a subtype of the T-cell immunoglobulin domain and mucin domain (Tim) protein family, might be an important regulatory molecule that plays a pivotal role in URSA, which might be triggered mostly by Th1/Th2 immune deviation. To understand the etiology and pathogenesis of URSA in Han Chinese women, we investigated the association between polymorphisms of rs10053538 and rs10515746 in the promoter of Tim-3 and the risk of URSA in Han Chinese women.

METHODS

One hundred and forty-eight women with RSA resulting in still birth were enrolled in the URSA group. We performed tests to rule out congenital reproductive system malformation, reproductive system tumor, endocrine dyscrasia, and chromosome abnormalities. One hundred and fifty-three women with normal pregnancy leading to live birth were selected at random to comprise the control group. All women included in this study were genetically unrelated Han Chinese women. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and allele-specific polymerase chain reaction (AS-PCR) were used to determine polymorphisms of rs10053538 and rs10515746, respectively, in all subjects. PCR products were chosen at random for sequencing.

RESULTS

No significant statistical difference was found between the distribution frequency of the GT + TT genotype and T allele on the rs10053538 locus in the URSA group or the control group (10.1% vs. 11.8%, Chi(2) = 0.205, P = 0.651; 5.1% vs. 6.5%, Chi(2) = 0.592, P = 0.441; respectively). Neither was there a significant difference between the distribution frequency of the GT + TT genotype and T allele on the rs10515746 locus in the groups (6.8% vs. 3.9%, Chi(2)1.201, P = 0.273; 3.4% vs. 2.0%, Chi(2) = 1.169, P = 0.280; respectively).

CONCLUSIONS

The present study suggested that these polymorphisms of rs10053538 or rs10515746 in the Tim-3 promoter may not be associated with URSA in Han Chinese women.

IVIg prevents the in vitro activation of T cells by neutralizing the T cell activators

Clinical observations in patients treated with IVIg revealed significant modulations in T cell populations and functions. However, it is unclear whether IVIg acts directly on activated T cells to suppress their functions. To clarify the exact mechanism of IVIg action, we studied its effect on T cells activated using anti-CD3/CD28 microbeads to mimic stimulatory signals provided by accessory cells. We report here that IVIg reduces T cell proliferation and cytokine secretion by interfering with the ability of anti-CD3/CD28 microbeads to deliver activating signals to T cells. We further show that the interference occurs between IVIg and anti-CD3/CD28 microbeads and does not involve T cells. In conclusion, our work suggests that T cells are not a direct target of IVIg and that the modulation of T cell populations and functions observed in treated patients is the indirect consequence of a direct effect of IVIg on accessory cells.

A high dose intravenous immunoglobulin therapy for women with four or more recurrent spontaneous abortions

Recurrent spontaneous abortion (RSA) may have immunological etiology. The aim of this study was to assess the efficacy of a high dose intravenous immunoglobulin (HIVIg) therapy, in which 20 g of intact type immunoglobulin was infused daily for 5 days during early gestation, for women who had a history of four or more consecutive spontaneous abortions of unexplained etiology. A total of 60 pregnant RSA women underwent HIVIg therapy, and the pregnancy outcome was assessed. The live birth rate was 73.3% (44/60). Fifteen pregnancies ended in spontaneous abortion, and one ended in intrauterine fetal death. In 11 of the 15 spontaneous abortions, fetuses had abnormal chromosome karyotype. When the 11 pregnancies with abnormal chromosome karyotype were excluded, the live birth rate was as high as 89.8% (44/49). The HIVIg therapy may be effective for severe cases of unexplained RSA.

Changes in the Th1:Th2 cytokine bias in pregnancy and the effects of the anti-inflammatory cyclopentenone prostaglandin 15-deoxy-Δ(12,14)-prostaglandin J2

Pregnancy is a complex immunological state in which a bias towards T helper 2 (Th2) protects the fetus. Evidence suggests that proinflammatory cytokines increase the risk of poor neonatal outcome, independently of the direct effect of preterm labour. The anti-inflammatory prostaglandin 15-deoxy-Δ^12,14-Prostaglandin J₂ (15dPGJ₂) inhibits nuclear factor Kappa B (NF-κB) in amniocytes and myocytes in vitro and is a ligand for the chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2) receptor. Here we examine the Th1:Th2 cytokine bias in pregnancy and whether 15dPGJ₂ could be used to inhibit the production of the proinflammatory cytokines through inhibition of NF-κB while simultaneously promoting Th2 interleukin 4 (IL-4) synthesis via CRTH2 in T helper cells. Peripheral blood mononuclear cells (PBMCs) from women at 28 weeks, term pre-labour, term labour as well as non-pregnant female controls were cultured with 15dPGJ₂ or vehicle control and stimulated with phorbol myristyl acetate (PMA)/ionomycin. The percentage of CD4⁺ cells producing interferon gamma (IFN-γ) and tumor necrosis factor alpha (TNF-α) in response to PMA/ionomycin was significantly reduced in pregnancy. 15dPGJ₂ reduced IFN-γ and TNF-α production in stimulated T helper cells, but did not alter IL-4 production in CRTH2^+ve cells. 15dPGJ₂ also reduced phospho-p65 in stimulated PBMCs. In summary, 15dPGJ₂ suppresses the Th1 response of PBMCs during pregnancy and active labour whilst maintaining the Th2 response suggesting a therapeutic benefit in reducing neonatal morbidity in inflammation-induced PTL.

Exogenous immunoglobulin downregulates T-cell receptor signaling and cytokine production

Intravenous immune globulin (IVIG), a polyvalent solution of pooled human immunoglobulin, is a potent immunomodulating agent. It is currently approved to treat autoimmune diseases, including idiopathic thrombocytopenia purpura, autoimmune hemolytic anemia, and Kawasaki disease. The basis of IVIG's immunomodulatory properties is not entirely understood. Proposed mechanisms include Fc receptor blockade, interference with cytokine network, and provision of anti-idiotypic antibodies. IVIG has also been shown to affect T-lymphocyte function, although a direct effect has been difficult to reconcile given the lack of immunoglobulin or Fc-receptors on T cells. Experiments were thus carried out to determine whether IVIG was acting on a specific T-cell subset and at the level of the T-cell receptor (TCR), and whether cytokine expression patterns were modulated. T lymphocytes obtained from adult peripheral blood and umbilical cord blood were cultured over a 1-wk time course in the presence of pharmacological IVIG concentrations (Gamunex(®) , 0-2.0 mg/ml). Cells were exposed to various stimulation conditions, and TCR signaling competence was assessed by quantifying activation-induced upregulation of CD25 and CD69, as well as production of specific T-cell cytokines. IVIG was found to significantly decrease T-lymphocyte proliferation, in a dose and time-dependent manner, in both cord and adult blood. IVIG markedly reduced phytohemagglutinin and anti-CD3-induced upregulation of CD25 and CD69 in both CD4 and CD8 T-cell subsets, although phorbol ester-induced responses were intact, suggesting a defect in the CD3/TCR signaling pathway. IVIG also inhibited anti-CD3-induced cytokine production of IL-10, IL-2, and IFN-γ in a dose-dependent manner. These data suggest that IVIG may have direct T-cell immunomodulatory properties by dampening TCR responses. Further studies are needed to more precisely define the molecular targets of IVIG.

Immunoglobulin treatment ameliorates myocardial injury in experimental autoimmune myocarditis associated with suppression of reactive oxygen species

AIMS

We tested the hypothesis that immunoglobulin ameliorated experimental autoimmune myocarditis (EAM) in mice attributing to the suppression of reactive oxygen species (ROS)-mediated myocardial injury.

METHODS

We intraperitoneally administered intact type of human immunoglobulin (Ig) or F(ab')2 fragments of human immunoglobulin, 1g/kg/day daily for 3 weeks, to male BALB/c mice with heart failure due to EAM.

RESULTS

The results showed that intact type of Ig, but not F(ab')2 type, reduced the severity of myocarditis by comparing the heart weight/body weight and lung weight/body weight ratios, pericardial effusion score, macroscopic and microscopic scores. Tissue superoxide production was marked in untreated mice with EAM, which was suppressed by the treatment of immunoglobulins. The cytotoxic activities of lymphocytes in mice with EAM treated with Ig were reduced compared with untreated controls. The shift from Th1 toward Th2 cytokine balance was demonstrated by the treatment of immunoglobulins both in vitro and in vivo.

CONCLUSION

ROS may be involved in the development of myocarditis. Intact Ig ameliorates myocardial damage in mice with myocarditis associated with suppression of ROS and cytotoxic activity of lymphocytes.

Neutralization of mitogenic lectins by intravenous immunoglobulin (IVIg) prevents T cell activation: does IVIg really have a direct effect on T cells?

Intravenous immunoglobulin (IVIg) is used for the treatment of an increasing number of autoimmune diseases. Clinical observations on IVIg-treated patients have revealed a modulation of T cell populations and functions in these patients. In vitro studies aimed at understanding the mechanisms underlying the effects of IVIg on T cells led to the conclusion that IVIg directly affected lectin-activated T cell functions. However, more recent studies have suggested the absence of a direct effect of IVIg on T cells. In the present work, we revisited the effect of IVIg on T cells using lectin-stimulated human T cells and showed that IVIg inhibited T cell functions only when added simultaneously with the activating lectin. Further, we showed that IVIg depleted from lectin-reactive IgG was no longer inhibitory, suggesting that the effect of IVIg on T cells was the consequence of lectin neutralization, possibly by interaction with glycans present in F(ab')(2) portion of IgG molecules. Our results challenge the previously widely accepted notion that IVIg exerts its anti-inflammatory effects by acting directly on T cells and suggest that effects of IVIg observed in treated patients are rather a consequence of the recently reported inhibitory effect of IVIg on antigen presentation.

Pro- and antiinflammatory cytokines in threatened miscarriages

OBJECTIVE

The purpose of this study was to evaluate circulating and intracellular levels of Th1 and Th2 cytokines in women with threatened miscarriage (TM) and subsequent outcome.

STUDY DESIGN

Plasma levels of tumor necrosis factor (TNF)-receptors 1 and 2, TNFα, interferon gamma (IFNγ), and interleukins (IL) -6 and -10 were measured by flow cytometric bead assays in 80 women with TM: 53 women with normal outcome and 27 women who miscarried. Fluorescent antibody labeling was also performed on whole blood in a subgroup of 27 women of TM: 16 women with normal outcome and 11 women who miscarried.

RESULTS

Monocyte expression of TNFα and circulating levels of TNFα, IFNγ, IL-10, IL-6, and TNF-R1 were significantly lower, whereas circulating levels of TNFα/IL-10, IFNγ/IL-10, and TNFα/IL-6 ratios were significantly higher, in women with TM who subsequently miscarried, compared with the women with normal outcome.

CONCLUSION

An increased Th1 type of immune response, which was similar to that observed in preterm delivery, was found in TM cases that were complicated by a subsequent miscarriage.

Intravenous immunoglobulin therapy for aspirin-heparinoid-resistant antiphospholipid syndrome

We encountered a woman who had a history of repeated fetal losses and positive tests for lupus anticoagulant, phosphatidylserine-dependent antiprothrombin (aPS/PT) IgG, IgM and kininogen-dependent antiphosphatidylethanolamine (aPE) IgG, IgM. Her previous pregnancy had ended in intrauterine fetal death at 24 weeks of gestation despite a therapy of low-dose aspirin, prednisolone and danaparoid. During the present pregnancy, she was treated with repeated intravenous infusions of immunoglobulin (IVIg) together with low-dose aspirin, prednisolone and heparin. When thrombocytopenia developed, she delivered a female baby weighing 2,152 g at 34 weeks of gestation by cesarean section. Titers of aPS/PT IgM and aPE IgM were reduced or maintained at low levels by repeated IVIg therapies. The IVIg therapy might be effective for aspirin-heparinoid-resistant antiphospholipid syndrome.

A high dose of intravenous immunoglobulin increases CD94 expression on natural killer cells in women with recurrent spontaneous abortion

PROBLEM

A high dose of intravenous immunoglobulin (HIVIg) therapy is effective in various diseases such as autoimmune diseases, and also is expected to have efficacy in recurrent spontaneous abortion (RSA). The aim of this study was to understand immunological mechanisms of this therapy.

METHOD OF STUDY

By flowcytometric analyses, we examined phenotypic changes of a variety of immunological cells including natural killer (NK) cells, cytotoxic T cells, regulatory T cells and macrophages in peripheral blood of RSA women with HIVIg therapy (n = 8).

RESULTS

Expression percentages of inhibitory CD94 on NK cells significantly (P = 0.01) increased after the therapy (58.8 +/- 21.4% versus 71.0 +/- 17.6%).

CONCLUSION

Mechanisms of possible efficacy of HIVIg therapy for RSA may include enhancement of CD94 expression and subsequent suppression of NK cell cytotoxicity.

Indirect inhibition of in vivo and in vitro T-cell responses by intravenous immunoglobulins due to impaired antigen presentation

Several clinical studies done with intravenous immunoglobulin (IVIg)-treated autoimmune patients as well as several in vitro studies have revealed that IVIg can reduce polyclonal T-cell activation and modify their cytokine secretion pattern. However, their effect on (auto)antigen-specific T-cell responses has never been addressed directly. In the present work, we used an in vivo model of induction of antigen-specific T-cell responses and an in vitro antigen presentation system to study the effects of IVIg on T-cell responses. The results obtained showed that IVIg inhibited both the in vivo and in vitro antigen-specific T-cell responses but that this effect was the indirect consequence of a reduction in the antigen presentation ability of antigen-presenting cells. The inhibitory effect of IVIg was FcgammaRIIb-independent, suggesting that IVIg must interfere with activating FcgammaRs expressed on antigen-presenting cells to reduce their ability to present antigens. Such inhibition of T-cell responses by reducing antigen presentation may therefore contribute to the well-known anti-inflammatory effects of IVIg in autoimmune diseases.

Anti-phospholipid antibodies and other immunological causes of recurrent foetal loss--a review of literature of various therapeutic protocols

PROBLEM

An immune-based aetiology is one of the several accepted causes for recurrent foetal loss (RFL). However, most of the immunological theories have not fulfilled the criteria for causality. This is a review of the various immunological causes of RFL and the outcome of different treatment protocols.

METHOD OF STUDY

Both auto- and alloimmune maternal immunological abnormalities have been proposed to account for foetal loss. Among the autoimmune factors, anti-phospholipid antibodies (APAs) have been demonstrated to be the strongest risk factors for foetal loss, the prevalence of which is as high as 40% in women with RFL. Other autoimmune antibodies implicated in RFL are anti-nuclear antibodies (ANAs), anti-thyroid antibodies and anti-endothelial cell antibodies. The alloimmune factors implicated in pregnancy loss of unknown aetiology include abnormal natural killer (NK) cell activity, alteration in T helper 1 (Th1) and T helper 2 (Th2) ratios, presence of alloimmune antibodies like anti-paternal cytotoxic antibodies, anti-idiotypic antibodies, mixed lymphocyte reaction blocking antibodies and abnormal expression of HLA-G molecules. Management of patients with RFL is mainly based on immunomodulatory (prednisolone, intravenous immunoglobulins, plasma exchange, paternal lymphocyte therapy), anti-aggregation (aspirin) or anti-coagulation (unfractionated or low molecular weight heparin) agents.

RESULTS

Low-molecular-weight heparin with low-dose aspirin has been found to be the most effective treatment for women with APAs and RFL. Differences in dosage, timing of treatment, inclusion criteria, outcome assessment parameters etc. are some of the factors which have resulted in discrepancies in various reports.

CONCLUSION

Identification of the immunological mechanisms involved in pregnancy loss and the action of different therapeutic reagents is important so that effective therapies can be designed and investigated.

Decline in number of elevated blood CD3(+) CD56(+) NKT cells in response to intravenous immunoglobulin treatment correlates with successful pregnancy

PROBLEM

Patients with elevated blood natural killer (NK) cells may be offered intravenous immunoglobulin (IVIG) treatment, but there is controversy about the utility of blood NK cell testing. Human CD56(+) NK cells include several subpopulations that include the putatively cytotoxic CD56(+) CD16(+) subset. In mouse models of pregnant failure, NKT cells appear to be important. However, a mouse model may only be pertinent to a subset of patients, as recurrent pregnancy failure is a heterogenous group.

METHOD OF STUDY

An ethics-approved observational study was done to observe the effect of treatment on total blood lymphoid cells, and subsets of CD56(+) blood lymphocytes including CD56(+) CD3(+) NKT cells determined by flow cytometry, and to correlate with pregnancy outcome. Fifteen fertile women with a history of successful pregnancy and thirty-one women suffering from repeated implantation failure or recurrent spontaneous abortion provided serial blood samples during one menstrual cycle or prior to and during treatment. IVIG was administered to the latter group with or without heparin/aspirin.

RESULTS

Eight of thirty infertile women presented with high numbers of CD56(+) CD3(+) NKT cells, which declined after treatment with IVIG. The elevated NKT cell group with or without concomitant autoimmunity achieved a significantly higher successful pregnancy rate over the course of the study, as compared to women with average numbers of NKT cells and no evidence of autoimmunity (P = 0.018). Elevated NKT levels alone was an independent predictor of success on treatment (P = 0.003).

CONCLUSION

Elevated NKT cells in recurrent pregnancy loss or implantation failure can be ameliorated with IVIG treatment, and result in successful pregnancy. Assay of NKT cell numbers may identify patients who are more likely to benefit from IVIG therapy and merits further examination in randomized phase II studies.

Elevated Th1/Th2 Cell Ratios in a Pregnant Woman with a History of RSA, Secondary Sj�gren?s Syndrome and Rheumatoid Arthritis Complicated with One Fetal Demise of Twin Pregnancy

PROBLEM

Elevated Th1/Th2 cytokine producing CD3(+)/CD4(+) cell ratios were reported in women with a history of recurrent spontaneous abortion (RSA) and multiple implantation failures. We report, significantly elevated Th1/Th2 cell ratios were noticed in a pregnant woman with twin pregnancies complicated with one fetal demise, who had a history of RSA, secondary Sjögren's syndrome (SS), and rheumatoid arthritis.

METHOD OF STUDY

Case report.

RESULTS

Peripheral blood Th1/Th2 cell ratios were significantly elevated 3 weeks prior to a fetal demise of twin pregnancies at 20 week gestation. Two weeks after fetal demise, the ratio of intracellular tumor necrosis factor-alpha/interleukin-10 producing CD3(+)/CD4(+) cells in peripheral blood was further increased to three times higher than prior ratio. Elevated Th1/Th2 ratio was down regulated after increasing dose of IVIg treatment. The patient gave birth to a male baby weighing 2650 g at 36 weeks gestation. No serious complications were found in the patient or the baby.

CONCLUSION

Systemic inflammatory immune response pre-exists prior to a fetal demise and the degree of inflammatory immune response got worse with a presence of fetal demise in utero. We infer that the placenta is not an immunological barrier to maternal Th1/Th2 immune responses.

Administration of high-dose intact immunoglobulin has an anti-resorption effect in a mouse model of reproductive failure

Administration of high-dose intact human immunoglobulin (IH-Ig) has been applied to treat a variety of inflammatory and autoimmune diseases, and is expected to have beneficial effects on human fecundity. In the present study, we investigated whether Ig had anti-resorption effects using polyinosinic-polycytidylic acid sodium salt [poly (I:C)]-induced enhancement of fetal resorption in the mating of CBA/J x DBA/2J resorption-prone mouse model. Furthermore, we investigated the mechanism of the effect by examining the mRNA expression of interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, IL-10, IL-4 and TGF-beta(1) in spleens and placentas from the resorption-prone model treated with IH-Ig, by reverse transcription (RT)-polymerase chain reaction (PCR). Administration of high-dose IH-Ig significantly reduced the fetal resorption rate from 55% to 10%. This anti-resorption effect, however, was not detected in mice administered with Fab fragments of human Ig. We then performed adoptive transfer experiments to examine whether cellular components could transfer the effect. A remarkable anti-resorption effect was seen in poly (I:C)-injected pregnant recipients transferred with spleen cells from IH-Ig-treated donor mice. The RT-PCR study showed that IH-Ig reduced the expression of IFN-gamma and TNF-alpha mRNA in placentas of poly (I:C)-injected pregnant mice. The present findings demonstrate that intact Ig, particularly its Fc portion, possesses anti-resorption activity. The effect might be attributed to the suppressed production of pro-inflammatory cytokines at the maternofetal interface.

High-dose intravenous immunoglobulins: an option in the treatment of systemic lupus erythematosus

Despite encouraging reports on the efficacy of intravenous immunoglobulin (IVIG) therapy in systemic lupus erythematosus (SLE), the clinical value of this treatment is not well established, and most of the data are based on case reports and small series of patients. IVIG has been used successfully to treat SLE patients with a broad spectrum of clinical manifestations, such as refractory thrombocytopenia, pancytopenia, central nervous system (CNS) involvement, secondary antiphospholipid syndrome, and lupus nephritis. The beneficial effects of IVIG on overall disease activity are usually prompt, with marked improvement within a few days, but they are often of limited duration. Improvement lasts for several weeks after the last infusion, although clinical response could be maintained by continuous monthly IVIG infusions. IVIG therapy immunomodulates autoimmune diseases by interacting with various Fcgamma receptors in such a way that it downregulates activating FcRIIA and FcRIIC and/or upregulates inhibitory FcRIIB. However, in SLE, additional mechanisms include inhibition of complement-mediated damage, modulation of production of cytokines and cytokine antagonists, modulation of T- and B-lymphocyte function, induction of apoptosis in lymphocytes and monocytes, downregulation of autoantibody production, manipulation of the idiotypic network, and neutralization of pathogenic autoantibodies. At present, IVIG in SLE is indicated either in severe cases that are nonresponsive to other therapeutic modalities, or when SLE can be controlled only with high-dose steroids; in such patients, IVIG thus becomes a useful steroid-sparing agent. However, this needs to be confirmed in double-blind, placebo-controlled studies.

Gene expression profiling of the effects of intravenous immunoglobulin in human whole blood

Intravenous immunoglobulin (IVIG) is involved in many complex mechanisms that act in synergy including expression and function of Fc receptors, complement activation, the cytokine network, interaction with the anti-idiotypic network and modulation of B and T cell activation. To gain insight into the early effects of IVIG on this broad range of activities at the gene level we performed DNA microarray analysis. Human whole blood was incubated in vitro for 4 h followed by extraction of RNA which was hybridized to a chip containing 8793 genes. About 75 upregulated genes and 21 downregulated genes were identified using a cut off for the false discovery rate of 5%. These genes are associated with a wide range of cellular immune functions in line with the broad mechanism of action of IVIG. A striking upregulation of a series of genes coding for chemokines was measured. This finding was confirmed at the protein level as pharmacologically relevant concentrations of CXCL9 and CXCL10 were measured in serum. Interestingly, IVIG shows a partial overlap of its gene expression program with lipopolysaccharide. Our data suggests multiple hypotheses regarding the pharmacology of IVIG that must be validated by complementary studies.

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".

Modulation of cytokine production by dydrogesterone in lymphocytes from women with recurrent miscarriage

OBJECTIVE

To examine the effects of dydrogesterone on the production of Th1 and Th2 cytokines by lymphocytes from women undergoing unexplained recurrent spontaneous miscarriage (RSM).

DESIGN

Controlled prospective, clinical study conducted in a maternity hospital and a university-based immunology laboratory.

SETTING

Faculty of Medicine, Kuwait University and Kuwait Maternity Hospital.

SAMPLE

Thirty women with unexplained RSM.

METHODS

Peripheral blood mononuclear cells (PBMC) from women with unexplained RSM were isolated from venous blood by density gradient sedimentation and stimulated with phytohaemagglutinin (PHA). Culture supernatants assayed for interferon (IFN)-gamma, tumour necrosis factor (TNF)-alpha, interleukin (IL)-4, IL-6 and IL-10 by ELISA. Levels of the progesterone-induced blocking factor (PIBF) were also measured.

MAIN OUTCOME MEASURES

Cytokine production in the presence and absence of progesterone and dydrogesterone.

RESULTS

Dydrogesterone significantly inhibited the production of the Th1 cytokines IFN-gamma (P= 0.0001) and TNF-alpha (P= 0.005) and induced an increase in the levels of the Th2 cytokines IL-4 (P= 0.03) and IL-6 (P= 0.017) resulting in a substantial shift in the ratio of Th1/Th2 cytokines. The effect of dydrogesterone was blocked by the addition of the progesterone-receptor antagonist mifepristone, indicating that dydrogesterone was acting via the progesterone receptor. Dydrogesterone induced the production of PIBF.

CONCLUSION

Dydrogesterone inhibits the production of the Th1 cytokines IFN-gamma and TNF-alpha from lymphocytes and up-regulates the production of the Th2 cytokines IL-4 and IL-6, inducing a Th1 to Th2 cytokine shift.

Is antibody therapy of tumor compromised by infusion-related reactions?

Evidence suggests that amelioration of childhood immune thrombocytopenic purpura and some other autoimmune states by intravenous normal IgG is due to the following chain of events: (1) cross-linking of Fcgamma-receptors on blood effector cells; (2) release of mediators from these cells, often yielding an infusion-related reaction; (3) mediator-induced development of a cytokine field characterized by a mutually stabilizing Th2 polarization of CD4 T lymphocytes and alternative activation of macrophages; (4) selective quiescence of these macrophages towards targets coated with IgG autoantibody, due to increased expression of the macrophage Fcgamma-receptor IIB. In this paper it is postulated that in the field of antibody therapy of tumor, an undesirable delayed or absent subsidence of antibody-coated tumor is due to immunomodulation of the same type as yields amelioration of autoimmunity, and arising from a similar chain of events. If the postulate is correct the chain could usefully be broken at the level of mediator action, possibly by blocking that increased synthesis of prostaglandin E(2) which is catalyzed by the enzyme cyclooxygenase-2.

Embryo loss pattern is predominant in miscarriages with normal chromosome karyotype among women with repeated miscarriage

OBJECTIVE

The aim of this study was to assess pregnancy loss patterns in women with repeated miscarriage (RM), according to fetal chromosome karyotypes and aetiologies of RM.

METHODS

In this cohort study, 168 fetal chromosome karyotypes of miscarriages were investigated. The pregnancy loss patterns were compared between 75 miscarriages from RM women who had a history of two or more consecutive miscarriages and 93 miscarriages from control women whose previous pregnancies ended in live births without a history of RM. By serial ultrasonography, embryo loss (EL) was defined as miscarriage before fetal heat movement was identified and fetal loss (FL) as miscarriage after fetal heat movement was identified. The EL rate was calculated as EL/(EL+FL).

RESULTS

The EL rate (66.7%) in miscarriages with normal karyotypes among RM women (n=42) was higher (P<0.05) than that (45.7%) in controls (n=46), while the EL rate (30.3%) in miscarriages with abnormal karyotypes among RM women (n=33) did not differ from that (25.5%) in the controls (n=47). The EL rate (71.4%) in miscarriages with normal karyotypes among unexplained RM women (n=21) was much higher (P<0.05) than that in the controls.

CONCLUSIONS

By evaluating fetal karyotypes, we demonstrated for the first time that EL was predominant in miscarriages with normal karyotype among RM women.