Immunology and the immunological response to pregnancy

Melatonin as a Therapy for Preterm Brain Injury: What Is the Evidence?

Despite significant improvements in survival following preterm birth in recent years, the neurodevelopmental burden of prematurity, with its long-term cognitive and behavioral consequences, remains a significant challenge in neonatology. Neuroprotective treatment options to improve neurodevelopmental outcomes in preterm infants are therefore urgently needed. Alleviating inflammatory and oxidative stress (OS), melatonin might modify important triggers of preterm brain injury, a complex combination of destructive and developmental abnormalities termed encephalopathy of prematurity (EoP). Preliminary data also suggests that melatonin has a direct neurotrophic impact, emphasizing its therapeutic potential with a favorable safety profile in the preterm setting. The current review outlines the most important pathomechanisms underlying preterm brain injury and correlates them with melatonin's neuroprotective potential, while underlining significant pharmacokinetic/pharmacodynamic uncertainties that need to be addressed in future studies.

Pathophysiological Insight into Fatty Acid-Binding Protein-4: Multifaced Roles in Reproduction, Pregnancy, and Offspring Health

Fatty acid-binding protein-4 (FABP4), commonly known as adipocyte-fatty acid-binding protein (A-FABP), is a pleiotropic adipokine that broadly affects immunity and metabolism. It has been increasingly recognized that FABP4 dysfunction is associated with various metabolic syndromes, including obesity, diabetes, cardiovascular diseases, and metabolic inflammation. However, its explicit roles within the context of women's reproduction and pregnancy remain to be investigated. In this review, we collate recent studies probing the influence of FABP4 on female reproduction, pregnancy, and even fetal health. Elevated circulating FABP4 levels have been found to correlate with impaired reproductive function in women, such as polycystic ovary syndrome and endometriosis. Throughout pregnancy, FABP4 affects maternal-fetal interface homeostasis by affecting both glycolipid metabolism and immune tolerance, leading to adverse pregnancy outcomes, including miscarriage, gestational obesity, gestational diabetes, and preeclampsia. Moreover, maternal FABP4 levels exhibit a substantial linkage with the metabolic health of offspring. Herein, we discuss the emerging significance and potential application of FABP4 in reproduction and pregnancy health and delve into its underlying mechanism at molecular levels.

Peripheral blood natural killer cell cytotoxicity in recurrent miscarriage: a systematic review and meta-analysis

Dysregulated natural killer (NK) cells have been associated with recurrent miscarriages (RM). Studies have suggested that high peripheral blood NK cell cytotoxicities (pNKCs) are associated with an increased risk of RM. The aim of this systematic review (SR) and meta-analysis (MAs) is to investigate the difference in pNKC between nonpregnant and pregnant women with RM and controls and determine whether pNKC is reduced by immunotherapy. We searched the PubMed/Medline, Embase, and Web of Science databases. The MAs were conducted to compare pNKCs between women with and without RM before and during pregnancy as well as pre- and post-immunotherapy. Risk of bias in nonrandomized studies was assessed by the Newcastle-Ottawa Scale. Statistical analysis was performed using the Review Manager software. A total of 19 studies were included in the SR and 14 studies in the MAs. The MAs revealed higher pNKCs among nonpregnant women with RM compared to controls (MD, 7.99 95 %CI 6.40-9.58; p < 0.00001). pNKCs were also higher in pregnant women with RM than in pregnant controls (MD, 8.21 95 %CI 6.08-10.34; p < 0.00001). Women with RM showed significantly decreased pNKCs after the immunotherapy compared to before (MD, -8.20 95 %CI -10.20 - -6.19; p < 0, 00001). Additionally, there is an association between high pNKCs and the risk of pregnancy loss in women with RM. However, included studies showed substantial heterogeneities regarding the inclusion criteria of patients, techniques measuring pNKC, and types of immunotherapies. More studies are needed to evaluate the clinical efficiency of pNKCs in managing RM.

Placenta analysis of Hofbauer cell profile according to the class of antiretroviral therapy used during pregnancy in people living with HIV

INTRODUCTION

The use of antiretroviral therapy drastically reduces vertical transmission of Human Immunodeficiency Virus. However, recent studies demonstrate associations between ART use during pregnancy and placental inflammation, particularly within protease inhibitor (PI)-based regimens. We sought to characterize placental macrophages, namely Hofbauer cells, according to the class of ART used during pregnancy.

METHODS

Using immunofluorescence and immunohistochemistry, placentas from 79 pregnant people living with HIV (PPLWH) and 29 HIV-uninfected people were analyzed to quantify the numbers and frequencies of leukocytes (CD45⁺) and Hofbauer cells (CD68⁺ and/or CD163⁺). PPLWH were stratified into three groups based on class of ART: non-nucleoside reverse transcriptase inhibitor (NNRTI)-based, integrase strand-transfer inhibitor (INSTI)-based, and PI-based regimens.

RESULTS

Placentas of PPLWH contained significantly more leukocytes and Hofbauer cells than controls. Multivariable analyses revealed that this increase in immune cells was associated with a predominantly CD163⁺ profile in all ART subgroups compared to the HIV-negative group. This was characterized by an increase in total CD163⁺ cells in the PI and INSTI subgroups, and a higher frequency of CD163⁺ cells and CD163⁺/CD68⁺ ratio in the NNRTI and PI subgroups.

DISCUSSION

Placentas of PPLWH treated with any ART regimen during their entire pregnancy displayed a selection for CD163⁺ cells compared to the HIV-negative group, regardless of class of ART, suggesting that class of ART does not intrinsically affect selection of CD163+ and CD68⁺ Hofbauer cells. Further investigations into the role of Hofbauer cells in ART-associated placental inflammation are warranted to identify the mechanisms behind their potential involvement in maternal-fetal tolerance maintenance.

Pyroptosis: A Promising Mechanism Linking SARS-CoV-2 Infection to Adverse Pregnancy Outcomes

Pregnancy is characterized by a delicate immune balance; therefore, infectious diseases might increase the risk of adverse pregnancy outcomes (APOs). Here, we hypothesize that pyroptosis, a unique cell death pathway mediated by the NLRP3 inflammasome, could link SARS-CoV-2 infection, inflammation, and APOs. Two blood samples were collected from 231 pregnant women at 11-13 weeks of gestation and in the perinatal period. At each time point, SARS-CoV-2 antibodies and neutralizing antibody titers were measured by ELISA and microneutralization (MN) assays, respectively. Plasmatic NLRP3 was determined by ELISA. Fourteen miRNAs selected for their role in inflammation and/or pregnancy were quantified by qPCR and further investigated by miRNA-gene target analysis. NLRP3 levels were positively associated with nine circulating miRNAs, of which miR-195-5p was increased only in MN+ women (p-value = 0.017). Pre-eclampsia was associated with a decrease in miR-106a-5p (p-value = 0.050). miR-106a-5p (p-value = 0.026) and miR-210-3p (p-value = 0.035) were increased in women with gestational diabetes. Women giving birth to small for gestational age babies had lower miR-106a-5p and miR-21-5p (p-values = 0.001 and 0.036, respectively), and higher miR-155-5p levels (p-value = 0.008). We also observed that neutralizing antibodies and NLRP3 concentrations could affect the association between APOs and miRNAs. Our findings suggest for the first time a possible link between COVID-19, NLRP3-mediated pyroptosis, inflammation, and APOs. Circulating miRNAs might be suitable candidates to gain a comprehensive view of this complex interplay.

In vitro-Generated MDSCs Reduce the Pregnancy Complications in an Abortion-Prone Murine Model

Recurrent spontaneous abortion (RSA) is one of the major pregnancy-related complications. The roles of different immune cells have been studied in pregnancy complications. The current study aimed to investigate myeloid-derived suppressor cells (MDSCs) in a murine abortion model and introduce a therapeutic approach by using in vitro-generated MDSCs in this model. CBA/J × DBA/2 (abortion prone) and CBA/J × Balb/C (normal pregnancy) mice were used. The frequency of granulocytic MDSCs, monocytic MDSCs, and Tregs was checked in the bone marrow and uteroplacental tissue of mice on three gestational days (gd9.5, gd13.5, and gd17.5) using the flow cytometry approach. MDSCs were generated in vitro from bone marrow-isolated cells using GM-CSF and IL-6 cytokines. Abortion-prone mice were injected intravenously with in vitro-generated MDSCs at gd0.5, and pregnancy outcomes were recorded in treated mice. The frequency of G-MDSCs and M-MDSCs in the bone marrow of abortion-prone mice was decreased at gd9.5 (p = 0.026 and p = 0.05, respectively). In uteroplacental tissue, the frequency of G-MDSCs was significantly lower at gd9.5 and gd13.5 (p = 0.001, p = 0.029, respectively), while M-MDSCs only showed decreased number at gd9.5 (p = 0.05) in abortion-prone mice. Injection of in vitro-generated MDSCs resulted in the increased fetus and placenta weights (p = 0.049 and p = 0.012, respectively) but showed no effect on the number of live fetuses and abortion rate. The reduced frequency of both G-MDSCs and M-MDSCs in the bone marrow and at the feto-maternal interface is associated with pregnancy complications. In vitro-generated MDSCs could be considered as a potential approach to reduce these complications.

The utility of systemic immune-inflammation index and systemic immune-response index in the prediction of adverse outcomes in pregnant women with coronavirus disease 2019: Analysis of 2649 cases

AIM

To investigate the association of systemic immune-inflammation index (SII) and systemic immune-response index (SIRI) with adverse perinatal outcomes in pregnant women with coronavirus disease 2019 (COVID-19).

METHODS

The cases were divided into (1) the Mild-moderate COVID-19 group (n = 2437) and (2) the Severe-critical COVID-19 group (n = 212). Clinical characteristics, perinatal outcomes, SII (neutrophilXplatelet/lymphocyte), and SIRI (neutrophilXmonocyte/lymphocyte) were compared between the groups. Afterward, SII and SIRI values were compared between subgroups based on pregnancy complications, neonatal intensive care unit (NICU) admission, and maternal mortality. A receiver operator characteristic analysis was performed for the determination of optimal cutoff values for SII and SIRI in the prediction of COVID-19 severity, pregnancy complications, NICU admission, and maternal mortality.

RESULTS

Both SII and SIRI were significantly higher in complicated cases (p < 0.05). Cutoff values in the prediction of severe-critical COVID-19 were 1309.8 for SII, and 2.3 for SIRI. For pregnancy complications, optimal cutoff values were 973.2 and 1.6. Cutoff values of 1045.4 and 1.8 were calculated for the prediction of NICU admission. Finally, cut-off values of 1224.2 and 2.4 were found in the prediction of maternal mortality.

CONCLUSION

SII and SIRI might be used in combination with other clinical findings in the prediction of poor perinatal outcomes.

Risk factors associated with preterm birth in singletons born after IVF: a national cohort study

RESEARCH QUESTION

What are the risk factors for prematurity other than intrauterine growth restriction in singletons after IVF?

DESIGN

Data were collected from a national registry, based on an observational prospective cohort of 30,737 live births after assisted reproductive technology (fresh embryo transfers: n = 20,932 and frozen embryo transfer [FET] n = 9805) between 2014 and 2015. A population of not-small for gestational age singletons conceived after fresh embryo transfers and FET, and their parents, was selected. Data on a number of variables were collected, including type of infertility, number of oocytes retrieved and vanishing twins.

RESULTS

Preterm birth occurred in 7.7% (n = 1607) of fresh embryo transfers and 6.2% (n = 611) of frozen-thawed embryo transfers (P < 0.0001; adjusted odds ratio [aOR] = 1.34 [1.21-1.49]). Endometriosis and vanishing twin increased the risk of preterm birth after fresh embryo transfer (P < 0.001; aOR 1.32 and 1.78, respectively). Polycystic ovaries or more than 20 oocytes retrieved also increased preterm birth risk (aOR 1.31 and 1.30; P = 0.003 and P = 0.02, respectively); large oocyte cohort (>20) was no longer associated with the risk of prematurity in FET.

CONCLUSION

Endometriosis remains a risk for prematurity even in the absence of intrauterine growth retardation, which suggests a dysimmune effect. Large oocyte cohorts obtained by stimulation, without clinical polycystic ovary syndrome diagnosed before attempts, do not affect FET outcomes, reinforcing the idea of a phenotypic difference in the clinical presentation of polycystic ovary syndrome.

Analysis of Causes of Maternal Death in East Java Province, Indonesia

BACKGROUND: The maternal mortality rate is an indicator that reflects the mother’s health status, especially the risk of death for the mother during pregnancy and childbirth. Measles, Mumps, and Rubella (MMR) has a close relationship with efforts to increase human development. Therefore, efforts are needed to reduce MMR by identifying the factors that influence MMR. AIM: The aim of the study was to analyze the factors causing the incidence of Maternal Death in East Java Province. METHODS: The research design used in this research is a quantitative research using descriptive-analytical. The population of this research is districts/cities in East Java Province, with a sample of 38 districts/cities. The research period starts from August to September 2021. Data analysis using grouping and percentage of cases. RESULTS: The results of the study found that cases of maternal death in East Java due to postpartum hemorrhage in 2021 were 131 cases. Cases due to hypertension as many as 115 cases. Cases due to infection as many as 25 cases. The incidence of maternal death due to abortion is 1 case. There were 13 cases of maternal death due to blood disorders. There were 6 cases of maternal death due to metabolic disorders — cases of maternal death due to Heart as many as 54 cases. Maternal deaths due to COVID-19 were 793 cases. CONCLUSION: Factors causing maternal death in East Java Province, namely, hypertension bleeding, infection, abortion, blood disorders, heart metabolic disorders, and COVID-19. The most influential factor in maternal mortality in 2021 is COVID-19.

Case report: Osimertinib administration during pregnancy in a woman with advanced EGFR-mutant non-small cell lung cancer

Lung cancer (LC) is one of the most common causes of death worldwide. The identification of oncogene-addicted driving mutations suitable for targeted therapy has improved clinical outcomes in advanced diseases. Clinical trials, on the other hand, rarely involve vulnerable groups such as pregnant women. We report a 37-year-old woman with advanced non-small cell lung cancer (NSCLC) harboring an exon 19 deletion of EGFR treated with afatinib. After the initial treatment, the patient achieved a complete response and had an unplanned pregnancy. Targeted therapy was withheld during the first trimester and resumed with osimertinib in the second trimester in which the patient developed oligohydramnios and intrauterine growth restriction (IUGR) of the baby. Osimertinib was delayed at two different times during the third trimester with complete resolution of the oligohydramnios. The baby was born at 37.3 weeks of gestation (WOG) with no signs of congenital disorders. After delivery, the mother restarted osimertinib and maintained a complete response. This case suggests that osimertinib could be an acceptable option for tumor control during pregnancy in EGFR-mutant NSCLC. This information do not replace current recommendations for avoiding pregnancy and promoting contraceptive usage in patients receiving any cancer therapy.

Pregnancy in lupus: an updated consensus to guide best practice strategies

Background

Systemic lupus erythematosus is a multifaceted chronic relapsing autoimmune disease of unknown etiology. The disease has always been a serious diagnosis in women being a multisystem pathology that is classically encountered during the childbearing age posing serious systemic comorbidities with a potential impact on the functional performance, psychosocial status, and survival. In this article, we review critical issues related to the decision to conceive in female with lupus highlighting the impact of the diagnosis and disease activity status on the mother and the fetus, attempting to suggest a consensus to guide safe decision making for pregnancy with SLE.

Main body

The pleomorphic dysregulated immune nature of lupus in the presence of uncontrolled disease carries a higher risk of complicated pregnancy. Therefore, SLE pregnancies should be well planned and are usually encouraged if the disease is inactive (at least 6 months prior to conception) to ensure immune quiescence towards a safer outcome.

Conclusion

With the proper implementation of preconception counseling strategy, choice of the correct timing of conception, close monitoring of SLE flares with tight control, and the appreciation of the value of multidisciplinary management to best practice most young women with SLE can carry on successful pregnancies with favorable outcome.

Partial otubain 1 deficiency compromises fetal well-being in allogeneic pregnancies despite no major changes in the dendritic cell and T cell compartment

Objective

Pregnancy is characterized by well-defined immunological adaptions within the maternal immune cell compartment allowing the survival of a genetically disparate individual in the maternal womb. Phenotype and function of immune cells are largely determined by intracellular processing of external stimuli. Ubiquitinating and deubiquitinating enzymes are known to critically regulate immune signaling either by modulating the stability or the interaction of the signaling molecules. Accordingly, if absent, critical physiological processes may be perturbed such as fetal tolerance induction. Based on previous findings that mice hemizygous for the deubiquitinating enzyme otubain 1 (OTUB1) do not give rise to homozygous progeny, here, we investigated whether partial OTUB1 deficiency influences fetal-wellbeing in a syngeneic or an allogeneic pregnancy context accompanied by changes in the dendritic cell (DC) and T cell compartment.

Results

We observed increased fetal rejection rates in allogeneic pregnant OTUB1 heterozygous dams but not syngeneic pregnant OTUB1 heterozygous dams when compared to OTUB1 wildtype dams. Fetal demise in allogeneic pregnancies was not associated with major changes in maternal peripheral and local DC and T cell frequencies. Thus, our results suggest that OTUB1 confers fetal protection, however, this phenotype is independent of immune responses involving DC and T cells.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13104-022-06230-w.

Differential proteomics of placentas reveals metabolic disturbance and oxidative damage participate yak spontaneous miscarriage during late pregnancy

Background

High spontaneous miscarriage rate in yak, especially during late pregnancy, have caused a great economic loss to herdsmen living in the Qinghai-Tibet plateau. However, the mechanism underlying spontaneous miscarriage is still poorly understood. In the present study, placenta protein markers were identified to elucidate the pathological reasons for yak spontaneous miscarriage through isobaric tags for relative and absolute quantification (iTRAQ) proteomic technology and bioinformatic approaches.

Results

Subsequently, a total of 415 differentially expressed proteins (DEPs) were identified between aborted and normal placentas. The up-regulated DEPs in the aborted placentas were significantly associated with “spinocerebellar ataxia”, “sphingolipid signalling”, “relaxin signalling”, “protein export”, “protein digestion and absorption” and “aldosterone synthesis and secretion” pathway. While the down-regulated DEPs in the aborted placentas mainly participated in “valine, leucine and isoleucine degradation”, “PPAR signalling”, “peroxisome”, “oxidative phosphorylation”, “galactose metabolism”, “fatty acid degradation”, “cysteine and methionine metabolism” and “citrate cycle” pathway.

Conclusions

The results implied that the identified DEPs could be considered as placental protein markers for yak miscarriage during late pregnancy, and biomacromolecule metabolic abnormality and oxidative damage might be responsible for the high spontaneous miscarriage rate in yak. These findings provide an important theoretical basis for deciphering the pathologic mechanism of late spontaneous miscarriage in yak.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-022-03354-w.

Confirmed reinfection with SARS‐CoV‐2 during a pregnancy: A case report

Pregnancy might impact immunity after SARS‐CoV‐2 infection and/or vaccination. We describe the first case of reinfection with SARS‐CoV‐2 during a pregnancy. While the mother lacked detectable antibodies 2 months after the first infection, both mother and baby had IgG antibodies at delivery. Infection did not cause any adverse pregnancy outcome.

Tolerability of the BNT162b2 COVID-19 Vaccine during Pregnancy among Polish Healthcare Professionals

The tolerance and safety of vaccination in pregnancy should be assessed in local populations based on ethnic differences across countries. Therefore, this study aimed to determine the tolerability of the BNT162b2 mRNA vaccination in pregnancy in a Polish population. An online questionnaire enquiring about the safety and tolerability of the BNT162b2 mRNA vaccine was distributed to pregnant and non-pregnant female healthcare professionals who had voluntarily received one or two doses of the COVID-19 vaccine in Poland. The two groups were compared simultaneously considering the COVID-19 infection status before vaccination. Compared with that noted in the control group, pregnant women in the COVID-19-free group were less likely to have fever (p = 0.002) or gastrointestinal symptoms (p = 0.009) after the second dose. In the COVID-19-exposed group, pregnant women were less likely to experience local skin reactions (p = 0.009), and myalgia (p = 0.003) after the first dose. After the second dose, the only noticeable difference was a lower incidence of myalgia (p = 0.001) in pregnant women. The tolerability of the BNT162b2 mRNA COVID-19 vaccine was similar in both the groups. No severe local, generalised, or pregnancy complications related to mother or foetus were observed. Good tolerability of the BNT162b2 mRNA COVID-19 vaccine in pregnancy in the Polish population may facilitate the decision to vaccinate pregnant women against COVID-19.

Complete Blood Count Peculiarities in Pregnant SARS-CoV-2-Infected Patients at Term: A Cohort Study

Background: During viral outbreaks, pregnancy poses an increased risk of infection for women. Methods: In a prospective study, all patients admitted for delivery at term to Elena Doamna Obstetrics and Gynecology University Hospital in Iasi, Romania, between 1 April 2020 and 31 December 2020 were included. There were 457 patients, divided into two groups: group 1, SARS-CoV-2-positive patients (n = 46) and group 2, SARS-CoV-2-negative patients (n = 411). Among other tests, complete blood count was determined upon admittance, and the following values were studied: white blood cell count, lymphocytes, neutrophils, red blood cell count, hemoglobin, mean corpuscular hemoglobin concentration, mean corpuscular hemoglobin, mean corpuscular volume, red blood cell distribution width, hematocrit, platelet count, mean platelet volume, platelet distribution width, plateletcrit, and platelet large cell ratio. Results: in pregnant SARS-CoV-2-infected patients at term, there was a significant decrease in white blood cell, neutrophil, and lymphocyte count, and an increase in mean corpuscular hemoglobin concentration, compared to healthy pregnant women at term, although all still within normal limits. None of the other components of the complete blood count or fetal outcomes studied was significantly influenced by SARS-CoV-2 infection in pregnant patients at term.