Uterine Dendritic Cells Research Articles

Glutamine metabolism shapes the phenotypic adaptation of uterine dendritic cells in response to early allogeneic pregnancy

Glutamine metabolism shapes the phenotypic adaptation of uterine dendritic cells in response to early allogeneic pregnancy

Immunohistochemical study of CD1a positive dendritic cells in normal, benign and malignant lesions of the human uterus and cervix

Introduction and Aim: Dendritic cells (DCs) perform the function of antigen-presenting cells of the immune system of mammals. After demonstration of DCs in the human cervix, more focus fell on the role of DCs distributed in various benign and cancerous lesions of endometrium. In our study, we have studied the role of CD1a positive DCs in non-malignant and cancerous tissues of the uterus and human cervix. Materials and Methods: A prospective analysis was conducted on patients who had undergone hysterectomy and cervical biopsy. After a detailed menstrual cycle history, the processed specimens were subjected for hematoxylin-eosin and immunohistochemical staining. The CD1a positive cells were counted per 20 high power fields and the mean cells per high power field (HPF) was calculated. Results: Eighty specimens were studied. Forty-six uterine and 34 cervix specimens were studied. The average chronological age of our study patients was 45.7 years. Bleeding per vaginum was the most common presentation. Fibroid uterus was the most common indication for hysterectomy. The minimum and maximum DCs amongst the 80 specimens were 1 and 246 per 20 HPF and the overall mean was 72.7. The mean cervical and uterine DCs per HPF were 7.7 and 0.7 respectively (P=0.0116). The average DCs per HPF in benign group were more than that in malignant specimens (9.23 and 1.76, respectively). Conclusion: A higher concentration of DCs in the cervical tissue was observed. Malignant tissues showed a lesser number of DCs than the benign specimens.

Endometrial Epithelial ARID1A Is Required for Uterine Immune Homeostasis during Early Pregnancy.

A growing body of work suggests epigenetic dysregulation contributes to endometriosis pathophysiology and female infertility. The chromatin remodeling complex subunit AT-rich interaction domain 1A (ARID1A) must be properly expressed to maintain normal uterine function. Endometrial epithelial ARID1A is indispensable for pregnancy establishment in mice through regulation of endometrial gland function; however, ARID1A expression is decreased in infertile women with endometriosis. We hypothesized that ARID1A performs critical operations in the endometrial epithelium necessary for fertility besides maintaining gland function. To identify alterations in uterine gene expression resulting from loss of epithelial ARID1A, we performed RNA-sequencing analysis on pre-implantation uteri from LtfiCre/+Arid1af/f and control mice. Differential expression analysis identified 4181 differentially expressed genes enriched for immune-related ingenuity canonical pathways including agranulocyte adhesion and diapedesis and natural killer cell signaling. RT-qPCR confirmed an increase in pro-inflammatory cytokine and macrophage-related gene expression but a decrease in natural killer cell signaling. Immunostaining confirmed a uterus-specific increase in macrophage infiltration. Flow cytometry delineated an increase in inflammatory macrophages and a decrease in uterine dendritic cells in LtfiCre/+Arid1af/f uteri. These findings demonstrate a role for endometrial epithelial ARID1A in suppressing inflammation and maintaining uterine immune homeostasis, which are required for successful pregnancy and gynecological health.

Cytochrome P450 26A1 modulates uterine dendritic cells in mice early pregnancy.

Cytochrome P450 26A1 (CYP26A1) plays important roles in the mice peri‐implantation period. Inhibiting its expression or function leads to pregnancy failure. However, little is known about the underlying mechanisms involved, especially the relationship between CYP26A1 and immune cells. In this study, using Cyp26a1‐specific antisense morpholigos (Cyp26a1‐MO) knockdown mice model and pCR3.1‐Cyp26a1 vaccine mice model, we found that the number of uterine CD45+CD11c+MHCIIlo‐hiF4/80− dendritic cells (DCs) was significantly decreased in the treated mice. The percentage of mature DCs (CD86hi) was obviously lower and the percentage of immature DCs (CD86lo) was remarkably higher in uterine DCs in the treatment group than that of the control group. Further experiments found that ID2, a transcription factor associated with DCs development, and CD86, a DC mature marker molecule, were both significantly reduced in mice uteri in the treated group. In vitro, ID2 and CD86 also decreased in bone marrow‐derived DCs under Cyp26a1‐MO treatment. These findings provide novel information that CYP26A1 might affect the embryo implantation via modulating the differentiation and maturation of uterine DCs.

Uterine Dendritic Cells Modulation by Mesenchymal Stem Cells Provides A Protective Microenvironment at The Feto-Maternal Interface: Improved Pregnancy Outcome in Abortion-Prone Mice.

Objective Dendritic cells (DCs) as major regulators of the immune response in the decidua play a pivotal role in establishment and maintenance of pregnancy. Immunological disorders are considered to be the main causes of unexplained recurrent spontaneous abortions (RSAs). Recently, we reported that mesenchymal stem cells (MSCs) therapy could improve fetal survival and reduce the abortion rate in abortion-prone mice, although the precise mechanisms of this action are poorly understood. Since MSCs have been shown to exert immunomodulatory effects on the immune cells, especially DCs, this study was performed to investigate the capability of MSCs to modulate the frequency, maturation state, and phenotype of uterine DCs (uDCs) as a potential mechanism for the improvement of pregnancy outcome. Materials and Methods In this experimental study, adipose-derived MSCs were intraperitoneally administered to abortion-prone pregnant mice on the fourth day of gestation. On the day 13.5 of pregnancy, after the determination of abortion rates, the frequency, phenotype, and maturation state of uDCs were analyzed using flow cytometry. Results Our results indicated that the administration of MSCs, at the implantation window, could significantly decrease the abortion rate and besides, increase the frequency of uDCs. MSCs administration also remarkably decreased the expression of DCs maturation markers (MHC-II, CD86, and CD40) on uDCs. However, we did not find any difference in the expression of CD11b on uDCs in MSCs-treated compared to control mice. ConclusionRegarding the mutual role of uDCs in establishment of a particular immunological state required for appropriate implantation, proper maternal immune responses and development of successful pregnancy, it seems that the modulation of uDCs by MSCs could be considered as one of the main mechanisms responsible for the positive effect of MSCs on treatment of RSA.

LILRB4 Decrease on uDCs Exacerbate Abnormal Pregnancy Outcomes Following Toxoplasma gondii Infection.

Toxoplasma gondii (T. gondii) infection in early pregnancy can result in miscarriage, dead fetus, and other abnormalities. The LILRB4 is a central inhibitory receptor in uterine dendritic cells (uDCs) that plays essential immune-regulatory roles at the maternal–fetal interface. In this study, T. gondii-infected human primary uDCs and T. gondii-infected LILRB4-/- pregnant mice were utilized. The immune mechanisms underlying the role of LILRB4 on uDCs were explored in the development of abnormal pregnancy outcomes following T. gondii infection in vitro and in vivo. Our results showed that the expression levels of LILRB4 on uDCs from normal pregnant mice were obviously higher than non-pregnant mice, and peaked in mid-gestation. The LILRB4 expression on uDC subsets, especially tolerogenic subsets, from mid-gestation was obviously down-regulated after T. gondii infection and LILRB4 decrease could further regulate the expression of functional molecules (CD80, CD86, and HLA-DR or MHC II) on uDCs, contributing to abnormal pregnancy outcomes. Our results will shed light on the molecular immune mechanisms of uDCs in abnormal pregnancy outcomes by T. gondii infection.

Embryo implantation dysfunction via the decreased uterine dendritic cells's non-immune function after exposed to carbon disulfide

Objective: To study the effect of CS2 on dendritic cells (DCs) in the uterus and the expression of vascular endothelial growth factor (VEGF), vascular endothelial growth factor receptor(fms-like tyrosine kinase-1, Flt-1), and to explore the toxic mechanism of CS2-induced embryo implantation dysfunction. Methods: The Kunming mice were randomly divided into control group,gestational day 4(GD4) exposure group and GD5 exposure group. The endpoints of each group(GD5, GD6, GD7) was set up according to their respective exposure time points. The mice in the exposure group were given intraperitoneal injection of CS2 at an injection dose of 631.4 mg/kg and the control group was given olive oil. The effect of CS2 on DCs in the uterus of pregnant mice was observed by flow cytometry. The levels of VEGF and Flt-1 were measured by Real-time quantitative polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assay (ELISA). Results: In the GD4 and GD5 exposure groups, the number of DCs in the uterus of pregnant mice decreased at all endpoints and the GD5 endpoint in the GD4 exposure group decreased by 21%(P=0.039), when compared with the control group. In the GD4 exposure group, the levels of VEGF mRNA and protein in the uterus of the pregnant mice were 79% and 30% lower than those in the control group, respectively (P=0.03、P=0.017); the levels of Flt-1 mRNA and protein at the endpoints of GD6 and GD7 in the uterus decreased by 54%, 36%, 60% and 56%, respectively, when compared with the control group(P=0.017、P=0.012、P=0.004、P=0.007). In the GD5 exposure group, the levels of VEGF mRNA and protein in the uterus of pregnant mice at the endpoint of GD7 decreased by 62% and 36%, when compared with the control group (P=0.005、P=0.035); the levels of Flt-1 mRNA and protein in the uterus at the endpoint of GD7 decreased by 60% and 44%, respectively, when compared with the control group (P=0.004、P=0.009). Conclusion: CS2 reduced the number of DCs in the uterus of pregnant mice, and affected the non-immune function of DCs, which affected uterine angiogenesis, this may be one of the mechanisms of CS2-induced embryo implantation dysfunction.

The decidua-the maternal bed embracing the embryo-maintains the pregnancy.

The decidua has been known as maternal uterine tissue, which plays essential roles in protecting the embryo from being attacked by maternal immune cells and provides nutritional support for the developing embryo prior to placenta formation. However, there are questions that still remain to be answered: (1) How does the decidua supply nutrition and provide a physical scaffold for the growing embryo, before placental vascular connection is established? (2) How is the balance between preventing an anti-embryo immune response and protecting both embryo and mother from infections established? To understand basic personas in decidual tissues, we review the structure of the decidua composed of terminally differentiated uterine stromal cells, blood vessels, and a number of repertoire of uterine local immune cells, including the well-known uterine natural killer (uNK) cells and recently discovered innate lymphoid cells (ILCs). Decidual macrophages and uterine dendritic cells (DCs) are supposed to modulate adaptive immunity via balancing cytokines and promoting generation of regulatory T (Treg) cells. During decidualization, vascular and tissue remodeling in the uterus provide nutritional and physical support for the developing embryo. Secretion of various cytokines and chemokines from both the embryo and the decidual cells activates multiple signaling network between the mother and the embryo upon implantation. Defects in the decidual development during early pregnancy result in loss of pregnancy or complications in later gestational stage.

Decidual cytokines and complications of pregnancy

uterine-draining lymphnodesbefore the implantation, and moved to the uterus after implantation. When a seminal vesicle-removed DBA/2 male mouse mated with a BALB/c female mouse, PA-Treg did not increase in the uterinedraining lymph nodes, suggesting that seminal plasma might play an important role in the induction of PA-Treg at the feto-maternal interface. Our recent data showed that seminal plasma-priming reduced the expression of MMCclass II and CD86 on uterine dendritic (u-DC) cells and enhanced the expression of B7-HC on u-DC cells, suggesting that seminal plasma might have induced the induction of tolerogenic DC in pregnant uterus. In human pregnancy, we have studied the population of CD4+Foxp3bright CD45RA−-functional Treg, CD4+Foxp3dimCD45RA+-naive Treg cells and CD4+Foxp3dim CD45RA−-activated T cells in the decidua of miscarriage cases. Functional Treg cells decreased and Foxp3+-activated T cells increased in the decidua ofmiscarriagewith normal chromosomal embryo. But these levels did not change in the decidua of miscarriage with abnormal chromosomal embryo, suggesting that decreased-functional Treg cells might induce miscarriage in humans. Samstein et al. reported that extrathymic Treg cells play a central role in the maintenance of allogeneic pregnancy in mice, but our data showed that Helios—extrathymic Treg cells constituted a minor population in human decidua and that these levels did not change in miscarriage with normal chromosomal embryo suggesting that thymic Treg cellsmight be important in the maintenance of pregnancy in humans.

Early Expression of Pregnancy-Specific Glycoprotein 22 (PSG22) by Trophoblast Cells Modulates Angiogenesis in Mice1

Mouse and human pregnancy-specific glycoproteins (PSG) are known to exert immunomodulatory functions during pregnancy by inducing maternal leukocytes to secrete anti-inflammatory cytokines that promote a tolerogenic decidual microenvironment. Many such anti-inflammatory mediators also function as proangiogenic factors, which, along with the reported association of murine PSG with the uterine vasculature, suggest that PSG may contribute to the vascular adaptations necessary for successful implantation and placental development. We observed that PSG22 is strongly expressed around the embryonic crypt on Gestation Day 5.5, indicating that trophoblast giant cells are the main source of PSG22 during the early stages of pregnancy. PSG22 treatment up-regulated the secretion of transforming growth factor beta 1 and vascular endothelial growth factor A (VEGFA) in murine macrophages, uterine dendritic cells, and natural killer cells. A possible role of PSGs in uteroplacental angiogenesis is further supported by the finding that incubation of endothelial cells with PSG22 resulted in the formation of tubes in the presence and absence of VEGFA. We determined that PSG22, like human PSG1 and murine PSG17 and PSG23, binds to the heparan sulfate chains in syndecans. Therefore, our findings indicate that despite the independent evolution and expansion of human and rodent PSG, members in both families have conserved functions that include their ability to induce anti-inflammatory cytokines and proangiogenic factors as well as to induce the formation of capillary structures by endothelial cells. In summary, our results indicate that PSG22, the most abundant PSG expressed during mouse early pregnancy, is likely a major contributor to the establishment of a successful pregnancy.

GM-CSF regulates uterine dendritic cell and macrophage maturation and antigen presentation

GM-CSF regulates uterine dendritic cell and macrophage maturation and antigen presentation

Seminal Advances in Immunology of Reproduction

INTRODUCTION The paper by Guerin et al. from Sarah Robertson’s group in this issue of Biology of Reproduction reports a major advance in our understanding of the mechanism(s) by which male semen may protect the implanting semi-allogeneic embryo against rejection by maternal innate and adaptive immune defenses. BALB/c (H-2) males were used with C56BL6 (H-2) females [1]. Following mating, the lymph nodes draining the uterus, (draining lymph nodes, DLN or para-aortic lymph nodes PALN) enlarge; this enlargement is greater when the male is allogeneic. i.e. histoincompatible with the female, and generation of anti-paternal cytotoxic T cells is suppressed [2]. The sequence of events is depicted in Figure 1. Seminal plasma (SP) and spermatozoa (S) ejaculated into the uterine lumen at the time of mating on gestation day 0 (GD 0) act on the uterine epithelium, sub-endothelial macrophages (Mph) and dendritic cells (DC). This leads to trafficking of cells (and perhaps the predominant chemokine CCL19) via afferent lymphatics to para-aortic lymph nodes draining the uterus (DLN or PALN). There, CCL19 recruits circulating regulatory T cells (Treg, identified by the presence of FOXP3) acting via the CCR7 receptor (and possibly CCR5) . DC may present antigens from SP (blue dots) or spermatozoa (red dots). Activated Treg cells exit the lymph nodes and home tothe uterine lining by GD day 3.5, again mediated for the most part by CCL19 binding to CCR7. Interestingly, measuring mRNA for Foxp3 showed an increase that was reduced by about half if SVX males lacking seminal plasma (SP) or VAS males lacking spermatazoa (S) were used, suggesting spermatozoa could activate Foxp3 mRNA in uterine cells without significantly increasing CCL19-dependent Treg cell recruitment, although both S+SP were required for maximal activation. On GD 4.5, the semi-allogeneic blastocyst, potentially susceptible to rejection directed against minor paternal histocompatibility antigens [2], implants. Guerin et al. argue that the regional generation and local recruitment of Treg cells to the uterus in advance of implantation acts to protect the implanting embryo against maternal immune rejection. In support of this contention, they noted an increase in CD4CD25 cells in the DLN that did not express FOXP3 and which could represent activated effector T cells.

GM-CSF Is an Essential Regulator of T Cell Activation Competence in Uterine Dendritic Cells during Early Pregnancy in Mice

Uterine dendritic cells (DCs) are critical for activating the T cell response mediating maternal immune tolerance of the semiallogeneic fetus. GM-CSF (CSF2), a known regulator of DCs, is synthesized by uterine epithelial cells during induction of tolerance in early pregnancy. To investigate the role of GM-CSF in regulating uterine DCs and macrophages, Csf2-null mutant and wild-type mice were evaluated at estrus, and in the periconceptual and peri-implantation periods. Immunohistochemistry showed no effect of GM-CSF deficiency on numbers of uterine CD11c(+) cells and F4/80(+) macrophages at estrus or on days 0.5 and 3.5 postcoitum, but MHC class II(+) and class A scavenger receptor(+) cells were fewer. Flow cytometry revealed reduced CD80 and CD86 expression by uterine CD11c(+) cells and reduced MHC class II in both CD11c(+) and F4/80(+) cells from GM-CSF-deficient mice. CD80 and CD86 were induced in Csf2(-/-) uterine CD11c(+) cells by culture with GM-CSF. Substantially reduced ability to activate both CD4(+) and CD8(+) T cells in vivo was evident after delivery of OVA Ag by mating with Act-mOVA males or transcervical administration of OVA peptides. This study shows that GM-CSF regulates the efficiency with which uterine DCs and macrophages activate T cells, and it is essential for optimal MHC class II- and class I-mediated indirect presentation of reproductive Ags. Insufficient GM-CSF may impair generation of T cell-mediated immune tolerance at the outset of pregnancy and may contribute to the altered DC profile and dysregulated T cell tolerance evident in infertility, miscarriage, and preeclampsia.

Progesterone regulation of uterine dendritic cell function in rodents is dependent on the stage of estrous cycle

Steroid hormones, such as progesterone, are able to modify immunity and influence disease outcome. Dendritic cells (DCs) drive potent immune responses, express receptors for steroid hormones, and may be a primary target of steroid hormone actions during infection of the genital tract, including uterine tissue. Here, we report that progesterone limited DC-associated activation marker expression and inhibited cytokine secretion by uterine DCs, which was associated with changes in signal transducer and activator of transcription 1 (STAT1) activity. We also found that DCs from mice at stages with higher progesterone concentrations (diestrus, metaestrus) were more sensitive to progesterone than those in stages with lower progesterone concentrations (proestrus, estrus), both in vitro and in vivo. This difference correlated with the levels of progesterone receptor expressed by DCs. These data suggest that progesterone regulates DC function and could contribute to the susceptibility of females to uterine and other genital tract infections at selected time periods throughout the life cycle.

GM-CSF regulates uterine macrophage and dendritic cell maturation and antigen presentation

GM-CSF regulates uterine macrophage and dendritic cell maturation and antigen presentation

Interaction between dendritic cells and natural killer cells during pregnancy in mice

A complex regulation of innate and adaptive immune responses at the maternal fetal interface promotes tolerance of trophoblast cells carrying paternally derived antigens. Such regulatory functions involve uterine dendritic cells (uDC) and natural killer (uNK) cells. The existence of a NK and DC "cross talk" has been revealed in various experimental settings; its biological significance ranging from cooperative stimulation to cell lysis. Little is known about the presence or role of NK and DC cross talk at the maternal fetal interface. The present study shows that mouse NK and DC interactions are subject to modulation by trophoblast cells in vitro. This interaction promotes a tolerogenic microenvironment characterized by downregulation of the expression of activation markers on uNK cells and uDC and dominance of Th2 cytokines. NK and DC interactions would also influence uterine cell proliferation and this process would be strongly modulated by trophoblast-derived signals. Indeed; while low proliferation rates were observed upon regular coculture allowing direct contact between uterine cells and trophoblasts, incubation in a transwell culture system markedly increased uterine cell proliferation suggesting that soluble factors are key mediators in the molecular "dialog" between the mother and the conceptus during the establishment of mouse pregnancy. Our data further reveal that the regulatory functions of trophoblast cells associated with tolerance induction are impaired in high abortion murine matings. Interestingly, we observed that secretion of interleukin-12p70 by uDC is dramatically abrogated in the presence of uNK cells. Taken together, our results provide the first evidence that a delicate balance of interactions involving NK cells, DC, and trophoblasts at the mouse maternal fetal interface supports a successful pregnancy outcome.

GMCSF Is an Essential Regulator of Uterine Dendritic Cells in Early Pregnancy.

GMCSF Is an Essential Regulator of Uterine Dendritic Cells in Early Pregnancy.

Dendritic Cells: Key to Fetal Tolerance?1

Pregnancy is a unique event in which a fetus, despite being genetically and immunologically different from the mother (a hemi-allograft), develops in the uterus. Successful pregnancy implies avoidance of rejection by the maternal immune system. Fetal and maternal immune cells come into direct contact at the decidua, which is a highly specialized mucous membrane that plays a key role in fetal tolerance. Uterine dendritic cells (DC) within the decidua have been implicated in pregnancy maintenance. DC serve as antigen-presenting cells with the unique ability to induce primary immune responses. Just as lymphocytes comprise different subsets, DC subsets have been identified that differentially control lymphocyte function. DC may also act to induce immunologic tolerance and regulation of T cell-mediated immunity. Current understanding of DC immunobiology within the context of mammalian fetal-maternal tolerance is reviewed and discussed herein.

Lipiodol alters murine uterine dendritic cell populations: A potential mechanism for the fertility-enhancing effect of lipiodol

To determine whether treatment with lipiodol alters the leukocyte population in the uterus. Randomized controlled animal study. University research laboratory. Sixty female Swiss white mice at proestrous. Infusion of the female reproductive tract with lipiodol versus infusion with saline versus sham treatment. Counts of uterine macrophages, dendritic cells, and total leukocytes assessed by immunohistochemistry. No statistically significant differences were found in the mean number of total leukocytes or macrophages between the three treatment groups. The mean number of CD205+ dendritic cells showed a statistically significant decrease following lipiodol treatment compared with the sham treatment and saline treatment. The mean number of CD1+ dendritic cells showed a statistically significant increase following lipiodol treatment compared with the sham treatment. Intrauterine lipiodol infusion is associated with a change in the uterine dendritic cell populations in mice. This change may alter the uterine immune response to the fetus, leading to improved fertility.

An Insight into the Dendritic Cells at the Maternal–Fetal Interface

The conditions that permit the genetically distinct fetus to survive and develop within the mother are among the most fascinating immunologic puzzles. The presence of dendritic cells in the maternal decidua pointed to a biologic role of antigen-presenting cells in maternal-fetal interaction. The method of study included recent findings on the lineage, maturity, phenotype and function of dendritic cells at the maternal-fetal interface. The increment of uterine dendritic cells occurs simultaneously with the decisive phase of gestation, when implantation takes place. Decidual dendritic cells of the first trimester pregnancy, with a phenotype characteristic of the mature myeloid lineage, express MHC class II, co-stimulatory and adhesion molecules, control Th1/Th2 balance and activate the proliferative response of autologous NK cells. Dendritic cells are specifically equipped to control immunity, to trigger immune response and also to maintain tolerance, avoiding the rejection of the conceptus by the maternal immune system.