Interleukin-10: a novel metabolic inducer of macrophage differentiation and subsequently contributing to improved pregnancy outcomes of mice by orchestrating oxidative phosphorylation metabolism†.

Metabolism regulates the phenotype and function of macrophages. After recruitment to local tissues, monocytes are influenced by the local microenvironment and differentiate into various macrophages depending on different metabolic pathways. However, the metabolic mechanisms underlying decidual macrophage differentiation remain unknown. Interleukin-10 (IL-10) is an important decidual macrophage inducer and promotes oxidative phosphorylation (OXPHOS) of bone marrow-derived macrophages. In this study, we mainly investigate the metabolic changes involved in IL-10-generated macrophages from monocytes using in vitro models. We demonstrate that exposure of monocytes (either peripheral or THP-1) to IL-10 altered the phenotype and function of resultant macrophages that are linked with OXPHOS changes. Interleukin-10 enhanced the mitochondrial complex I and III activity of THP-1 cell-differentiated macrophages and increased the mitochondrial membrane potential, intracellular adenosine triphosphate, and reactive oxygen species levels. Oxidative phosphorylation blockage with oligomycin changed the cell morphology of IL-10-generated macrophages and the expression levels of cytokines, such as transforming growth factor beta, tumor necrosis factor-alpha, interferon gamma, and IL-10, apart from changes in the expression level of the surface markers CD206, CD209, and CD163. Moreover, in vivo IL-10 administration reduced the lipopolysaccharide (LPS)-induced embryo resorption rate, and this effect was diminished when OXPHOS was inhibited, demonstrating that OXPHOS is important for the improved pregnancy outcomes of IL-10 in LPS-induced abortion-prone mice. Our findings provide deep insights into the roles of IL-10 in macrophage biology and pregnancy maintenance. Nevertheless, the direct evidence that OXPHOS is involved in decidual macrophage differentiation needs further investigations.

The immune checkpoint protein PD-1: Its emerging regulatory role in memory T cells.

Immunological memory helps the body rapidly develop immune defense when it re-encounters a bacterial or viral strain or encounters a similar mutation in healthy cells. The immune checkpoint molecule programmed cell death 1 (PD-1) influences memory T cell differentiation. However, the mechanism by which PD-1 regulates the development and maintenance of memory T cells and its impact on memory T cells function remain unclear. In this review, we first discuss the structure and function of PD-1 and then summarize the roles of PD-1 as a marker of tumor memory T cells and in tumor immunotherapy. We also discuss the potential mechanisms through which PD-1 regulates memory T cells development and maintenance during immune diseases such as viral infection-mediated diseases, psoriasis, and rheumatoid arthritis, and list the effects of PD-1 on memory T cells in pregnancy and their function in maternal-fetal immune balance. A complete understanding of how PD-1 influences the development, maintenance, and function of memory T cells will provide new insights into the prevention and treatment of immune-related diseases.

Flip a coin: cell senescence at the maternal-fetal interface†.

During pregnancy, cell senescence at the maternal-fetal interface is required for maternal well-being, placental development, and fetal growth. However, recent reports have shown that aberrant cell senescence is associated with multiple pregnancy-associated abnormalities, such as preeclampsia, fetal growth restrictions, recurrent pregnancy loss, and preterm birth. Therefore, the role and impact of cell senescence during pregnancy requires further comprehension. In this review, we discuss the principal role of cell senescence at the maternal-fetal interface, emphasizing its "bright side" during decidualization, placentation, and parturition. In addition, we highlight the impact of its deregulation and how this "dark side" promotes pregnancy-associated abnormalities. Furthermore, we discuss novel and less invasive therapeutic practices associated with the modulation of cell senescence during pregnancy.

Age-related changes in CD4+ T and NK cell compartments may contribute to the occurrence of pregnancy loss in advanced maternal age.

A recent study characterized novel immune cell subsets (T, NK, and γδ T cell subsets) related to recurrent pregnancy loss (RPL). This study aims to assess whether these RPL-related immune cell subsets are affected by aging. The percentages of peripheral blood immunes cells from nulligravida women (NGW), women with a history of normal pregnancy (NP), and women with a history of pregnancy loss (PL) were detected by flow cytometry. The correlations between maternal age and cell percentages were assessed. We found a significant positive correlation between PL and maternal age. The percentages of effector memory CD4+ T (CD3+ CD4+ CD45RA¯ CCR7¯), terminally differentiated CD4+ T (CD3+ CD4+ CD45RA+ CCR7¯), and mature NK cells (CD3¯ CD56+lo) significantly increased with maternal age. A significant decrease in the percentage of Naïve CD4+ T cells (CD3+ CD4+ CD45RA+ CCR7+) with age was observed in women from the NP group. Women aged 35 or older had significantly higher percentages of effector memory CD4+ T cells, terminally differentiated CD4+ T cells, and mature NK cells than younger women. Maternal age positively correlates with terminally differentiated CD4+ T, effector memory CD4+ T, and mature NK cell percentages. In contrast, an inverse correlation was observed between Naïve CD4+ T cell and age among women from the NP group. Our findings indicate that age-related CD4+ T and NK cell dysregulation might be involved in the pathogenesis of PL in women with advanced maternal age. The underlying mechanism needs further investigation.

Altered vitamin D metabolism is involved in the dysregulation of γδT cell function and their crosstalk with trophoblasts in recurrent pregnancy loss.

BACKGROUND: Recurrent pregnancy loss (RPL) is a common disease characterized by immune dysfunction and vitamin D deficiency. This study aimed to investigate vitamin D metabolism and γδT cell phenotypes at the maternal-fetal interface in women with early normal pregnancy (NP) and RPL and to determine the effects of vitamin D on the functions of γδT cells and their crosstalk with trophoblasts. METHODS: The levels of 25-(OH)VD3 , the expression of vitamin D metabolic enzymes in the villi, and the proportion of γδT cells in the decidua were detected in women with NP and RPL. After treatment with different concentrations of vitamin D, the mRNA expression of the vitamin D receptor (VDR), cytokines, and transcription factors were detected in Vδ2+ γδT cells. In addition, the proliferation, migration, and invasion of HTR-8/SVneo trophoblasts were determined by coculturing them with vitamin D-treated Vδ2+ γδT cells and their supernatants. RESULTS: In women with RPL, the level of 25-(OH)VD3 in the villi was increased; however, that of CYP27B1 (enzyme converting 25-(OH)VD3 into 1,25-(OH)2 VD3 ) was decreased. In addition, the proportion of Vδ2+ γδT cells increased, whereas that of Foxp3+ Vδ2+ γδT cells decreased in the decidua of women with RPL. An in vitro study showed that vitamin D increased the expression of VDR mRNA and Foxp3, but decreased the expression of IFN-γ mRNA, in Vδ2+ γδT cells. Finally, vitamin D-treated Vδ2+ γδT cells promoted trophoblast migration and invasion. CONCLUSIONS: Abnormal vitamin D metabolism and γδT cell proportions were present at the maternal-fetal interface in women with RPL. Under normal pregnancy conditions, vitamin D can induce the differentiation of decidual Vδ2+ γδT cells toward an anti-inflammatory phenotype (Treg-like γδT cells) and modulate the crosstalk between Vδ2+ γδT cells and trophoblasts.

Leukocyte immunoglobulin-like receptor subfamily B: A novel immune checkpoint molecule at the maternal-fetal interface.

Due to their crucial roles in embryo implantation, maternal-fetal tolerance induction, and pregnancy progression, immune checkpoint molecules (ICMs), such as programmed cell death-1, cytotoxic T-lymphocyte antigen 4, and T cell immunoglobulin mucin 3, are considered potential targets for clinical intervention in pregnancy complications. Despite the considerable progress on these molecules, our understanding of ICMs at the maternal-fetal interface is still limited. Identification of alternative and novel ICMs and the combination of multiple ICMs is urgently needed for deeply understanding the mechanism of maternal-fetal tolerance and to discover the causes of pregnancy complications. Leukocyte immunoglobulin-like receptor subfamily B (LILRB) is a novel class of ICMs with strong negative regulatory effects on the immune response. Recent studies have revealed that LILRB is enriched in decidual immune cells and stromal cells at the maternal-fetal interface, which can modulate the biological behavior of immune cells and promote immune tolerance. In this review, we introduce the structural features, expression profiles, ligands, and orthologs of LILRB. In addition, the potential mechanisms and functions mediated by LILRB for sustaining the maternal-fetal tolerance microenvironment, remodeling the uterine spiral artery, and induction of pregnancy immune memory are summarized. We have also provided new suggestions for further understanding the roles of LILRB and potential therapeutic strategies for pregnancy-related diseases.

IL-10: A bridge between immune cells and metabolism during pregnancy.

Energy metabolism plays a crucial role in the immune system. In addition to providing vital energy for cell growth, reproduction and other cell activities, the metabolism of nutrients such as glucose and lipids also have significant effects on cell function through metabolites, metabolic enzymes, and changing metabolic status. Interleukin-10 (IL-10), as a pleiotropic regulator, can be secreted by a diverse set of cells and can also participate in regulating the functions of various cells, thereby playing an essential role in the formation and maintenance of immune tolerance in pregnancy. Studies on the regulatory effects and mechanisms of IL-10 on immune cells are extensive; however, research from a metabolic perspective is relatively negligible. Here, we have discussed old and new data on the relationship between IL-10 and metabolism. The data show that alterations in cellular metabolism and specific metabolites regulate IL-10 production of immune cells. Moreover, IL-10 regulates immune cell phenotypes and functions by modulating oxidative phosphorylation and glycolysis. This review summarizes some earlier observations regarding IL-10 and its relationship with immune cells in pregnancy, and also presents recent research on the link between IL-10 and metabolism, highlighting the potential relationship between IL-10, immune cells, and energy metabolism during pregnancy.

Human leukocyte antigens: the unique expression in trophoblasts and their crosstalk with local immune cells.

Trophoblasts differentiate and form the placenta during pregnancy in a complex and finely orchestrated process, which is dependent on the establishment of maternal-fetal immune tolerance and the proper function of trophoblasts. Trophoblasts express HLA-C and non-classical HLA-Ib molecules (HLA-E, HLA-F, and HLA-G). Numerous studies have shown that the unique expression pattern of the HLA molecules is closely linked to the successful acceptance of allogeneic fetus by the mother during pregnancy. However, some controversies still exist concerning the exact expression and recognition patterns of HLA molecules in different trophoblast subpopulations and cell lines. Thus, we summarize three types of trophoblast subpopulations as well as the common trophoblast lineages. Then, the classification and structural characteristics of HLA molecules were elucidated. Finally, the presence of HLA-C and non-classical HLA-Ib molecules (HLA-E, HLA-F, and HLA-G) in various trophoblasts and cell lines, as well as their potential role in establishing and maintaining normal pregnancy were also discussed. Together, this review will help people comprehensively understand the complex immune interactions between maternal and fetal crosstalk during pregnancy and ultimately better understand the physiological and pathological etiologies of pregnancy.

Phosphoglycerate mutase 5 promotes necroptosis in trophoblast cells through activation of dynamin-related protein 1 in early-onset preeclampsia.

OBJECTIVES: Placentae from patients with preeclampsia have increased susceptibility to necroptosis and phosphoglycerate mutase 5 (PGAM5) plays a role in many necrosis pathways. We determined whether PGAM5 promotes necroptosis of trophoblast cells and the underlying mechanisms in this study. METHODS: The injury model was established by treating JEG3 cells with hypoxia for 24 h. The functional measurements were assessed by the cell counting kit-8, propidium iodide (PI)/Annexin V staining, JC-1 staining and firefly luciferase ATP assay. The expression of proteins in human placentae and JEG3 cells was measured Western blot. PGAM5 was knocked down to study its role in hypoxia-induced necroptosis. RESULTS: The placentae from patients with preeclampsia showed up-regulation of PGAM5 and decreased levels of p-Drp1-S637, accompanied by increased necroptosis-relevant proteins expression. The expression of PGAM5 in JEG3 cells was up-regulated under hypoxia, which promoted dephosphorylation of Drp1 at Serine 637 residue, mitochondrial dysfunction (elevated ROS level and reduced mitochondrial membrane potential and ATP content) and cellular necroptosis (increased PI+ /Annexin V+ cells and decreased cell viability), accompanied by increased expression of necroptosis-relevant proteins; knockdown of PGAM5 attenuated these phenomena. CONCLUSIONS: Our results indicate that PGAM5 can promote necroptosis in trophoblast cells through, at least in part, activation of Drp1. It may be used as a new therapeutic target to prevent trophoblast dysfunction in preeclampsia.

Systemic Characterization of Novel Immune Cell Phenotypes in Recurrent Pregnancy Loss.

Recurrent pregnancy loss (RPL) is a disturbing disease in women, and 50% of RPL is reported to be associated with immune dysfunction. Most previous studies of RPL focused mainly on the relationship between RPL and either T cells or natural killer (NK) cells in peripheral blood and the decidua; few studies presented the systemic profiles of the peripheral immune cell subsets in RPL women. Herein, we simultaneously detected 63 immune cell phenotypes in the peripheral blood from nonpregnant women (NPW), women with a history of normal pregnancy (NP) and women with a history of RPL (RPL) by multi-parameter flow cytometry. The results demonstrated that the percentages of naïve CD4+ T cells, central memory CD4+ T cells, naïve CD8+ T cells, mature NK cells, Vδ1+ T cells and the ratio of Vδ1+ T cells/Vδ2+ T cells were significantly higher in the RPL group than those in the NPW and NP groups, whereas the percentages of terminal differentiated CD4+ T cells, effective memory CD4+ T cells, immature NK cells and Vδ2+ T cells were significantly lower in the RPL group than those in the NPW and NP groups. Interestingly, we found that peripheral T helper (TPH) cells were more abundant in the NPW group than in the NP and RPL groups. In addition, we also determined the 5th percentile lower limit and 95th percentile upper limit of the significantly changed immunological parameters based on the files of the NPW group. Taken together, this is the first study to simultaneously characterize the multiple immune cell subsets in the peripheral blood at a relatively large scale in RPL, which might provide a global readout of the immune status for clinicians to identify clinically-relevant immune disorders and guide them to make clear and individualized advice and treatment plans.

Hypertensive disorders of pregnancy and risks of adverse pregnancy outcomes: a retrospective cohort study of 2368 patients.

Hypertensive disorders of pregnancy (HDP) comprise a group of hypertension-related diseases and represent the most common medical disorders in pregnancy. The aim of this study was to investigate the risks of adverse pregnancy outcomes in patients with different types of HDP, including gestational hypertension, chronic hypertension, preeclampsia (PE, early or late onset), PE superimposed on chronic hypertension (superimposed PE), eclampsia, and HELLP syndrome. Data from a multicenter retrospective patient cohort in China were analyzed. Seventeen adverse maternal or perinatal outcomes were evaluated. Logistic regression was used to estimate the risk of adverse outcomes for each HDP subgroups, using the gestational hypertension group as the reference. The final analysis included 2368 patients with HDP. Of these, 39.9% of patients reported at least one adverse pregnancy outcome. Patients with early onset PE had the highest risk for having both adverse maternal and perinatal outcomes (OR = 7.28, 95% CI: 2.68, 19.79). The risk of perinatal death significantly increased in HELLP syndrome, superimposed PE, and early onset PE, (OR = 13.81, 6.32, and 4.84, respectively, p < 0.05) groups. This study highlights that among patients with HDP, those with early onset PE had the highest risk for having both adverse maternal and perinatal outcomes, and patients with HELLP syndrome had the highest risk for perinatal death.

Quercetin Prevents Lipopolysaccharide-Induced Experimental Preterm Labor in Mice and Increases Offspring Survival Rate.

Premature labor is still a worldwide problem, causing serious social economic burden and family burden. Currently, there is no effective way to prevent preterm labor. Since inflammation increases the risk of preterm birth and quercetin is reported to have anti-inflammation, immune-enhancement, and antioxidative effects, this study aims to explore whether quercetin exerts inhibitory effect on preterm labor in mice and increases offspring survival. Lipopolysaccharide (LPS) is one of the commonly used drugs in the inflammatory animal model of preterm birth. On day 15 of pregnancy, mice received a dose of vehicle phosphate-buffered saline (PBS) or a dose of quercetin (low concentration, 30 mg/kg; medium concentration, 90 mg/kg; high concentrations, 150 mg/kg) via oral gavage. After 2 h, mice received a dose of LPS (50 µg/kg) or vehicle intraperitoneally (i.p.). In the absence of quercetin, a 100% incidence of preterm labor was observed in LPS-treated mice, and the fetuses were all died. Medium concentration of quercetin significantly prevented 63.5% of LPS-induced inflammatory preterm labor, and the survival rate of pups on day 22 was 83.76%. Specifically, quercetin significantly inhibited LPS-induced upregulation of NF-kappa-B/P65(RELA), AP-1/C-JUN(JUN), cyclooxygenase-2(PTGS2), and interleukin 6(IL6) in mice myometrium on mRNA level and inhibited the upregulation of P65 and C-JUN on protein level. Based on these observations, we concluded that quercetin exerts inhibitory effect on LPS-induced experimental mice preterm labor and increases offspring survival through a mechanism involving NF-κB/AP-1 pathway.

Generation of a homozygous HDAC6 knockout human embryonic stem cell line by CRISPR/Cas9 editing.

Histone deacetylase 6 (HDAC6) is a unique cytoplasmic enzyme in the HDAC family. The HDAC6 has been shown to play important roles in several biological processes. Meanwhile, it is also an attractive therapeutic target for a variety of diseases. However, the mechanism of HDAC6 function is not fully understood yet, and it is still lacking highly specific targeted drugs. Here, we generated a homozygous HDAC6 knockout human embryonic stem cell (hESC) line, WAe009-A-21 by the CRISPR/Cas9-based gene editing method. The WAe009-A-21 cell line does not express HDAC6 protein, while maintaining normal 46, XX karyotype, pluripotency, and trilineage differentiation potential.

Preterm birth, low birthweight, and small for gestational age among women with preeclampsia: Does maternal age matter?

OBJECTIVES: To better understand the effects of maternal age on birth outcomes among preeclampsia (PE) patients, we examined the rates of preterm birth, low birthweight, and small for gestational age (SGA) among different age groups and explored whether maternal age was associated with those adverse outcomes. STUDY DESIGN: This is a multicenter retrospective study. Data from 1128 PE patients, including 580 with early onset PE and 548 with late onset PE, were analyzed. MAIN OUTCOME MEASURES: Maternal age was categorized into three groups: <25, 25-34, and ≥35 years. The outcome variables were preterm birth (<37 weeks; subgroups: <28 weeks, 28-33 weeks, and 34-36 weeks), low birthweight (<2500 g; subgroups: <1500 g and <1000 g), and SGA. Logistic regression was used to analyze the associations between maternal age groups and outcomes. RESULTS: In early onset PE, compared with maternal age 25-34 years, maternal age ≥35 years was associated with elevated risk for preterm delivery before 28 weeks, and maternal age <25 years was associated with elevated risk for low birthweight and SGA. When the analysis was restricted to women who underwent cesarean section, elevated risks for preterm birth and/or low birthweight were observed for women younger than 25 years in both early and late onset PE. CONCLUSIONS: Among women with PE, maternal age <25 years could add risk to preterm birth and/or low birthweight. For women with early onset PE, maternal age ≥35 years is a risk factor for preterm delivery before 28 weeks.

Risk factors for adverse maternal and perinatal outcomes in women with preeclampsia: analysis of 1396 cases.

Preeclampsia is a major cause of adverse maternal and perinatal outcomes, but how to identify women and fetuses at increased risk for later adverse events is a challenge. This study aimed to investigate the risk factors for adverse maternal and perinatal outcomes in women with preeclampsia. Data from 1396 women with preeclampsia were retrospectively collected and analyzed. Eighteen candidate risk factors and 12 adverse outcomes were investigated. The following factors were found to be significantly associated with at least one adverse outcome: maternal age 35 years or older, multiple birth, the usage of assisted reproductive technology, living in a rural area, history of pregnancy-induced hypertension, male fetus, multigravida, or having polycystic ovary syndrome, hemolysis, elevated liver enzymes, and low platelet count syndrome, intrahepatic cholestasis of pregnancy, cardiovascular disease, gestational diabetes mellitus, systemic lupus erythematosus, thyroid disease, or liver disease. Compared with patients without any identified risk factors, patients with preeclampsia with three or more risk factors were at increased risk for severe adverse outcomes. Those findings demonstrated that maternal risk factors could be used as indicators supplementary to clinical symptoms and laboratory test results for the risk assessment in women with preeclampsia.

Increased expression of long noncoding RNA ABHD11-AS1 in gastric cancer and its clinical significance.

Long noncoding RNAs (lncRNAs) play an important role in basic physiological processes, also affect tumor occurrence and development. However, there are still many unknown relationships between the lncRNA expression levels and gastric tumor process. In our study, we selected ABHD11 Antisense RNA 1 (ABHD11-AS1) as a representative lncRNAs to study the different expression levels between gastric tumor and adjacent non-tumor tissues. At the same time, we analyzed the relationship between the expression levels of ABHD11-AS1 in gastric cancer tissues and the clinicopathological features of patients with gastric cancer and evaluated the diagnostic value through the receiver operation characteristic (ROC) curve. Results show that compared with adjacent non-tumor tissues the expression level of ABHD11-AS1 in gastric cancer tissues was significantly increased (P = 0.027). The expression level was also significantly related with the differentiation (P = 0.022), Lauren histologic classification (P = 0.004) and carbohydrate antigen 19-9 (CA19-9) (P = 0.007), and the area under ROC curve was up to 0.613. Thus, ABHD11-AS1 might be a potential biomarker for diagnosis of gastric cancer.