bims-reprim Biomed News
on Reproductive immunology
Issue of 2020‒09‒13
six papers selected by
Iva Filipovic
Karolinska Institutet

  1. FASEB J. 2020 Sep 11.
    Li T, Li X, Guo Y, Zheng G, Yu T, Zeng W, Qiu L, He X, Yang Y, Zheng X, Li Y, Huang H, Liu X.
      Early non-chromosome-related missed abortion (MA) is commonly associated with an altered immunological environment during pregnancy. Human decidual natural killer (dNK) cells, the most abundant lymphocyte population within the first-trimester maternal-fetal interface, are vital maternal regulators of immune tolerance mediating successful embryo implantation and placentation. Previous studies have shown that dNK cells may play a role in MA. However, the gene expression status and specific altered manifestations of dNK cells in patients with early MA remain largely unknown. Here, we show that MA dNK cells have distinct mRNA and lncRNA expression profiles through RNA sequencing, with a total of 276 mRNAs and 67 lncRNAs being differentially expressed compared with controls. Protein-protein interaction analysis of differentially expressed mRNAs was performed to identify hub genes and key modules. An lncRNA-mRNA regulatory network characterized by the small-world property was constructed to reveal the regulation of mRNA transcription by differential hub lncRNAs. Functional annotation of differentially expressed mRNAs and lncRNAs was performed to disclose their potential roles in MA pathogenesis. Our data highlight several enriched biological processes (immune response, inflammatory response, cell adhesion, and extracellular matrix [ECM] organization) and signaling pathways (cytokine-cytokine receptor interaction, ECM-receptor interaction, Toll-like receptor signaling pathway, and phosphatidylinositol signaling system) that may influence MA. This study is the first to demonstrate the involvement of altered mRNA and lncRNA expression profiles in the dNK cell pathogenesis of early MA, facilitating a better understanding of the underlying molecular mechanisms and the development of novel MA therapeutic strategies targeting key mRNAs and lncRNAs.
    Keywords:  RNA sequencing; functional annotation; lncRNA-mRNA interaction network; mRNA and lncRNA profiles; protein-protein interaction
  2. Proc Natl Acad Sci U S A. 2020 Sep 08. pii: 202014272. [Epub ahead of print]
    Dhakal P, Kelleher AM, Behura SK, Spencer TE.
      Glands of the uterus are essential for pregnancy establishment. Forkhead box A2 (FOXA2) is expressed specifically in the glands of the uterus and a critical regulator of glandular epithelium (GE) differentiation, development, and function. Mice with a conditional deletion of FOXA2 in the adult uterus, created using the lactotransferrin iCre (Ltf-iCre) model, have a morphologically normal uterus with glands, but lack FOXA2-dependent GE-expressed genes, such as leukemia inhibitory factor (LIF). Adult FOXA2 conditional knockout (cKO; Ltf iCre/+ Foxa2 f/f ) mice are infertile due to defective embryo implantation arising from a lack of LIF, a critical implantation factor of uterine gland origin. However, intraperitoneal injections of LIF can initiate embryo implantation in the uterus of adult FOXA2 cKO mice with pregnancies maintained to term. Here, we tested the hypothesis that FOXA2-regulated genes in the uterine glands impact development of the decidua, placenta, and fetus. On gestational day 8.5, the antimesometrial and mesometrial decidua transcriptome was noticeably altered in LIF-replaced FOXA2 cKO mice. Viable fetuses were reduced in FOXA2 cKO mice on gestational days 12.5 and 17.5. Sex-dependent differences in fetal weight, placenta histoarchitecture, and the placenta and metrial gland transcriptome were observed between control and FOXA2 cKO mice. The transcriptome of the placenta with a female fetus was considerably more altered than the placenta with a male fetus in FOXA2 cKO dams. These studies reveal previously unrecognized sexually dimorphic effects of FOXA2 and uterine glands on fetoplacental development with potential impacts on offspring health into adulthood.
    Keywords:  FOXA2; gland; placenta; pregnancy; uterus
  3. Proc Natl Acad Sci U S A. 2020 Sep 11. pii: 201915075. [Epub ahead of print]
    Mackey E, Thelen KM, Bali V, Fardisi M, Trowbridge M, Jordan CL, Moeser AJ.
      Mast cell (MC)-associated diseases, including allergy/anaphylaxis and neuroinflammatory pain disorders, exhibit a sex bias, with females at increase risk. While much attention has been directed toward adult sex hormones as drivers of sex differences, that female sex bias in MC-associated diseases is evident in prepubertal children, suggesting early-life origins of sex differences which have yet to be explored. Utilizing rodent models of MC-mediated anaphylaxis, our data here reveal that, 1) compared with females, males exhibit significantly reduced severity of MC-mediated anaphylactic responses that emerge prior to puberty and persist into adulthood, 2) reduced severity of MC-mediated anaphylaxis in males is linked with the naturally high level of perinatal androgens and can be recapitulated in females by perinatal exposure to testosterone proprionate, 3) perinatal androgen exposure guides bone marrow MC progenitors toward a masculinized tissue MC phenotype characterized by decreased concentration of prestored MC granule mediators (e.g., histamine, serotonin, and proteases) and reduced mediator release upon degranulation, and 4) engraftment of MC-deficient Kit W-sh/W-sh mice with adult male, female, or perinatally androgenized female MCs results in MC-mediated anaphylaxis response that reflects the MC sex and not host sex. Together, these data present evidence that sex differences in MC phenotype and resulting disease severity are established in early life by perinatal androgens. Thus, factors affecting levels of perinatal androgens could have a significant impact on MC development and MC-associated disease risk across the life span.
    Keywords:  histamine; immune; inflammation; mast cell; sex differences
  4. Acta Obstet Gynecol Scand. 2020 Sep 06.
    Crona Guterstam Y, Strunz B, Ivarsson MA, Zimmer C, Melin AS, Jonasson AF, Björkström N, Gidlöf SB.
      INTRODUCTION: The menstrual cycle is regulated by a complex interplay between endometrial epithelial cells, endothelial cells, immune cells, and sex hormones. To communicate, cells secrete cytokines that have multiple and diverse effects on recipient cells. The knowledge of how these cells interact in the uterus is insufficient. Menstrual blood is easily accessible and provides a source to study menstrual cycle physiology. This study aimed to determine the cytokine profile in menstrual blood plasma and investigate the differences in cytokine profiles between menstrual and peripheral blood plasma. Several previous studies indicate an improved chance of embryo implantation after endometrial scratching. Consequently, our secondary aim was to compare the menstrual blood cytokine profile before and after luteal phase endometrial scratching.MATERIAL AND METHODS: 19 healthy donors collected menstrual blood for the first 24 hours of menstruation in two sequential cycles. Matched peripheral blood was taken at the same time. An endometrial biopsy was performed at cycle day 7-9 post ovulation in between the two collection times. A Luminex multiplex assay was performed in one batch analyzing a pre-determined group of cytokines in plasma.
    RESULTS: Peripheral blood plasma and menstrual blood plasma showed substantial significant differences in cytokine profile. In menstrual blood plasma, C5/C5a, IL-6, IL-1β, and CXCL8 were detected in high concentrations, whereas IL-2, IL-12p70, XCL1/Lymphotactin, and IFN-γ were low. The most pronounced median differences between menstrual and peripheral blood plasma were found for IL-6, IL-1β, and CXCL8. The cytokine profiles of menstrual blood plasma were similar between the individual donors and did not differ over two subsequent cycles. None of the cytokines analyzed in menstrual blood plasma differed significantly before or after luteal phase endometrial scratching (P<0.01).
    CONCLUSIONS: Our results demonstrate that the menstrual blood cytokine profile is distinctly different from peripheral blood plasma and that the inter-individual difference in menstrual blood cytokine profile in healthy donors is limited and stable over time. The small injury of a performed endometrial biopsy does not change the cytokine profile in the subsequent menstrual cycle. Our study provides new insights into menstrual cycle physiology.
    Keywords:  Cytokine; chemokine; endometrial scratching; interleukin; menstrual blood; multiplex assay
  5. Semin Immunopathol. 2020 Sep 07.
    Green ES, Arck PC.
      Preterm birth (PTB) complicates 5-18% of pregnancies globally and is a leading cause of maternal and fetal morbidity and mortality. Most PTB is spontaneous and idiopathic, with largely undefined causes. To increase understanding of PTB, much research in recent years has focused on using animal models to recapitulate the pathophysiology of PTB. Dysfunctions of maternal immune adaptations have been implicated in a range of pregnancy pathologies, including PTB. A wealth of evidence arising from mouse models as well as human studies is now available to support that PTB results from a breakdown in fetal-maternal tolerance, along with excessive, premature inflammation. In this review, we examine the current knowledge of the bidirectional communication between fetal and maternal systems and its role in the immunopathogenesis of PTB. These recent insights significantly advance our understanding of the pathogenesis of PTB, which is essential to ultimately designing more effective strategies for early prediction and subsequent prevention of PTB.
    Keywords:  Fetal signals; Inflammatory signaling pathways; Labor; Microbiome; Mouse models; Preterm birth; Regulatory T cells
  6. Nat Protoc. 2020 Sep 09.
    Sheridan MA, Fernando RC, Gardner L, Hollinshead MS, Burton GJ, Moffett A, Turco MY.
      The human placenta is essential for successful reproduction. There is great variation in the anatomy and development of the placenta in different species, meaning that animal models provide limited information about human placental development and function. Until recently, it has been impossible to isolate trophoblast cells from the human placenta that proliferate in vitro. This has limited our ability to understand pregnancy disorders. Generating an in vitro model that recapitulates the unique features of the human placenta has been challenging. The first in vitro model system of human trophoblast that could be cultured long term and differentiated to syncytiotrophoblast (SCT) and extravillous trophoblast (EVT) was a two-dimensional (2D) culture system of human trophoblast stem cells. Here, we describe a protocol to isolate trophoblast from first-trimester human placentas that can be grown long term in a three-dimensional (3D) organoid culture system. Trophoblast organoids can be established within 2-3 weeks, passaged every 7-10 d, and cultured for over a year. The structural organization of these human trophoblast organoids closely resembles the villous placenta with a layer of cytotrophoblast (VCT) that differentiates into superimposed SCT. Altering the composition of the medium leads to differentiation of the trophoblast organoids into HLA-G+ EVT cells which rapidly migrate and invade through the Matrigel droplet in which they are cultured. Our previous research confirmed that there is similarity between the trophoblast organoids and in vivo placentas in their transcriptomes and ability to produce placental hormones. This organoid culture system provides an experimental model to investigate human placental development and function as well as interactions of trophoblast cells with the local and systemic maternal environment.