The uterine immune profile: A method for individualizing the management of women who have failed to implant an embryo after IVF/ICSI.

A unique endometrial immune reaction should occur to promote the human embryo implantation. We postulated that an immune disequilibrium may impact the initial dialogue between the mother and her embryo. In 2012, we set a method of uterine immune profiling for patients with unexplained repeated implantation failures (RIF). The method documents the local Th-1/ Th-2 equilibrium and the recruitment and state of maturation/activation of uNK cells. In function of the disequilibrium observed, personalization of assisted reproductive treatments was suggested. As the concept of personalization in function of the uterine immune profile had never been proposed, a large cohort study and a controlled cohort study were first conducted in RIF patients. 80 % of the RIF patients showed a local disequilibrium if compared to fertile controls. The local disequilibrium was identified in 3 categories: over-immune activation in 45 %, low- local immune activation in 25 % and mixed profile in 10 %. Personalization of treatments in function of the immune profile allowed to restore a live birth rate by 40 % at the following embryo transfer. RIF patients with endometriosis show some particularities regarding their immune profiles. We also suggested that immunotherapy (corticoids, intralipids) may have targeted indications based on a better understanding of the immune type of disequilibrium documented. Personalization of treatments for RIF patients seems to be essential to promote the subsequent live birth rate. The endometrial immune profiling is an innovative method aiming to detect a local immune disequilibrium and, if present, to test preventively its correction under treatment.

Sera from early-onset, severely preeclamptic women directly modulate HLA-E expression in the EA.hy296 endothelial cell line.

The expression of endothelial HLA-E in the context of the systemic inflammatory response observed in preeclampsia has not been established. An experimental study was designed to determine the effect of the sera of pregnant women on the expression of HLA-E in EA.hy296 endothelial cells. First, measurements of protein fractions were performed in sera from early-onset, severely preeclamptic women without HELLP syndrome, in which there was no significant difference in total proteins between the groups, but a reduced level of plasma albumin and an increase in α1-globulin were observed in both groups of pregnant women compared with non-pregnant women. Measurements of colloid osmotic pressure (COP) using a recalculated albumin/globulin ratio formula determined only a significant decrease in COP in all pregnant groups compared with non-pregnant women. The expression of membrane HLA-E was increased in EA.hy296 endothelial cells stimulated with sera of early-onset, severely preeclamptic women, while recombinant interferon-γ (IFN-γ) significantly reduced the expression of membrane HLA-E. Pro-inflammatory cytokines were measured by Luminex in the serum samples, and increased levels of tumor necrosis factor (TNF) and decreased levels of IFN-γ were observed in early-onset, severe preeclampsia compared with normal pregnancy. Moreover, soluble HLA-E was detected in these serum samples by Western blot and ELISA, but no significant difference was found. This raises the possibility that a systemic inflammatory response promotes a compensatory mechanism of COP balance in severe preeclampsia by release of inflammation-induced factors, including endothelial HLA-E. Evidence is now provided regarding HLA-E expression by EA.hy296 cells.

Cytokine production by non-stimulated peripheral blood NK cells and lymphocytes in early-onset severe pre-eclampsia without HELLP.

Preeclampsia involves an exacerbated maternal inflammatory response that suggests a possible role of innate immunity. NK cells can promote this kind of response through cytokine production and the expression of activating or inhibitory receptors. The aims of the present study were to explore cytokine production by peripheral blood mononuclear cells, as well as cytotoxic ability and receptor expression for HLA-E and HLA-G molecules in peripheral natural killer (NK) cells of women with early-onset severe preeclampsia without HELLP (hemolysis, elevated liver enzyme levels and a low platelet count) syndrome. The expression of the ILT2, KIRDL4, NKG2A, and NKG2C receptors and of cytotoxic activity was measured in non-stimulated NK cells, whereas the intracellular expression of IL-4, IL-10, IL-13, IL-12, IFNγ, TNF and VEGF, was assessed in non-stimulated peripheral blood mononuclear cells subsets using flow cytometry. Circulating soluble HLA-G was also determined by ELISA. The intracellular cytokines tested were significantly higher in NK cell subsets from severely preeclamptic women compared with the control group. On the other hand, the percentage of NK cells expressing NKG2A or NKG2C and the cytotoxic activity of NK cells were significantly higher in severely preeclamptic women. Furthermore, there was a significant correlation between urine protein concentration and soluble human leukocyte antigen G (soluble HLA-G) in serum. We conclude that patients with early-onset severe preeclampsia without HELLP syndrome have increased NK cell function related to cytokine production, cytotoxicity and expression of lectin-like receptors such as NKG2.

New pre-conception immune biomarkers for clinical practice: interleukin-18, interleukin-15 and TWEAK on the endometrial side, G-CSF on the follicular side.

Identification of biomarkers of optimal uterine receptivity to the implanting embryo as well as biomarkers of oocyte competence would undoubtedly improve the efficiency of assisted reproductive technology (ART). Expression of IL-15 and IL-18 has been shown to be different in patients with failed implantation after IVF/ICSI compared with fertile controls and both correlate with local uNK (CD56+) recruitment and angiogenesis. Tumor necrosis factor weak inducer of apoptosis (TWEAK) has been described in mice as a potent early immune regulator able to protect the conceptus. The results of our studies in human suggest that TWEAK modulates the IL-18 related cytotoxicity of uNK cells. Quantification of IL-18, TWEAK and IL-15 mRNA expression by real-time PCR in endometrial tissue collected in mid-luteal phase of non-conception cycles allowed documentation of physiological events that occur at the time of uterine receptivity. Such information may be useful for the physician especially in patients where embryos fail to implant. Cytokine quantification may assist in understanding the mechanisms leading to repeated IVF/ICSI failure: either depletion of cytokines necessary for the apposition-adhesion, or an excess of cytokines leading to local cytotoxicity, may impair the implantation of the embryo. Other new data suggest that a pre-conception dialogue mediated by the oocyte and the follicular fluid and the oocyte may contribute to later implantation success. Follicular concentration of G-CSF appears as a useful biomarker of oocyte competence before fertilization. Moreover both in human and animal models, evidence of a role of the endometrium as a biosensor of the embryo is emerging.

Higher interleukin-18 and mannose-binding lectin are present in uterine lumen of patients with unexplained infertility.

The uterine luminal environment was explored with regard to interleukin-18 (IL-18) and mannose-binding lectin (MBL) and the possibility that the procedure of flushing the uterine cavity would optimize the physiological initial pseudo-inflammatory uterine reaction. Uterine flushings were performed among 175 IVF/intracytoplasmic sperm injection (ICSI) patients at the time of oocyte retrieval and the cycles were compared with a control group matched for age, number of previous attempts and type of assisted reproductive procedure (IVF or ICSI) in which no flushing were performed (n = 175). Samples collected were divided into two groups according to the presence/absence of endometrial cells in samples. IL-18 and MBL expressions were explored by enzyme-linked immunosorbent assay. Implantation rates were significantly higher in those patients who underwent the uterine flushing compared with controls (P = 0.04). Luminal concentrations of IL-18 and MBL were higher if endometrial cells were present in flushings, suggesting endometrial origin of the secretion. Both concentrations of MBL and IL-18 were higher in patients with unexplained infertility compared with patients involved in IVF/ICSI for male or tubal infertility (P = 0.005 and 0.02, respectively). The exploration of the endoluminal environment before oocyte retrieval may enhance pregnancy rates and show distinct features in patients with unexplained infertility.

[Current debates on immunology of preeclampsia. Report of the sixth international workshop of Reunion Island (Indian Ocean, December 2008)]. / Débats actuels sur l'immunologie de la prééclampsie. Comptes rendus du sixième colloque international de La Réunion (décembre 2008).

Hypertensive disorders of pregnancy (HDP) represent globally 10% of human births and their major complication, preeclampsia, 3 to 5%. The etiology of these HDP remains still uncertain, however major advances have been made these last 25 years. The Sixth International Workshop on Reproductive Immunology, Immunological Tolerance and Immunology of Preeclampsia 2008 celebrated its 10th Anniversary in Reunion-island (French overseas Department in the Indian Ocean). Over this decade, these six workshops have contributed extensively to immunological, epidemiological, anthropological and even vascular debates. The defect of trophoblastic invasion encountered in preeclampsia, intra-uterine growth retardation and to some extend also preterm labour has been understood only at the end of the 1970's. On the other hand, clinical and epidemiological findings at the end of the 20th century permitted to apprehend that "preeclampsia disease of primiparae" may in fact well be the disease of first pregnancies at the level of human couples. Among the important advances, immunology of reproduction is certainly the topic where knowledge has literally exploded in the last decade. This paper relates some major steps in comprehension of this disease and focuses on the interest to follow these immunological works and their new concepts. It seems, at the beginning of the 21st century, that we are possibly closer than ever to understand the etiology of this obstetrical enigma. In this quest, the immunology of reproduction will certainly come out as one of the main players.

Cytokines and chemokines in follicular fluids and potential of the corresponding embryo: the role of granulocyte colony-stimulating factor.

BACKGROUND: The cytokine/chemokine levels of individual follicular fluids (FFs) were measured to determine whether a biomarker could be linked to the developmental potential of the derived embryo. METHODS: Fluid was collected from 132 individual FFs that were the source of oocytes subsequently fertilized and transferred. In each, a bead-based multiplex sandwich immunoassay (Luminex) was used to measure 28 cytokines and chemokines simultaneously. RESULTS: Significantly higher levels of interleukin (IL-2) and interferon (IFN-gamma) were detected in FF for embryos that underwent early cleavage. IL-12 was significantly higher in FF corresponding to highly fragmented embryos and the chemokine CCL5 was significantly higher in FF related to the best quality (Top) embryos. The level of granulocyte colony-stimulating factor (G-CSF) in individual FF samples was correlated with the implantation potential of the corresponding embryo. The area under the receiver operating characteristics curve, which distinguished the embryos that definitely led to delivery from those that did not, was 0.84 (0.75-0.90) (P = 0.0001) for FF G-CSF. FF G-CSF was significantly lower in patients older than 36 years compared with those <30-year old. When the FF G-CSF was 20 pg/ml or higher, the ratio between Top and non-Top embryos was significantly higher than for the group with FF G-CSF below 20 pg/ml (45 versus 20.45%, P = 0.007). CONCLUSIONS: Individual FF composition is related to the development of the corresponding in vitro generated embryo and its potential of implantation. Individual FF G-CSF may provide a non-invasive biomarker of implantation that needs to be evaluated together with in vitro observation to select the oocyte, and hence the embryo, to transfer.

[Physiology of implantation]. / Physiologie de l'implantation.

This article explains why we have had to come to a central role for innate immunity rather than the threat of maternal rejection of the foetal allograft. We encompass briefly the role of inflammation in implantation, not only for invasion adhesion, but also to prepare future "tolerance". In this context, we envisage the role of TWEAK and complement.

Characterization of the main placental cytokine profiles from HIV-1-infected pregnant women treated with anti-retroviral drugs in France.

Cytokines are involved in regulating HIV-1 infection. They are also placental environment major components. We assessed the potential impact of HIV-1 infection and/or anti-retroviral drugs on the placental cytokine profiles that may be involved in controlling HIV-1 placental dissemination. Placental explants were obtained after elective caesarean section from anti-retroviral-treated HIV-1-infected pregnant women and from HIV-1 non-infected pregnant women. The main placental cytokines were assessed for protein secretion in the supernatants of 24-h placental culture explants and/or in uncultured placental explants for mRNA expression levels. The cytokine profiles were different between the HIV-1-infected and the non-infected groups. Higher medians of leukaemia inhibiting factor (LIF), tumour necrosis factor (TNF)-alpha and interleukin (IL)-8 secretion were found in the 24-h culture supernatant of term placenta from HIV-1-infected women. High median levels of IL-16 and regulated upon activation normal T cell expressed and secreted (RANTES) levels were found in both groups. The mRNA expression medians were lower for TNF-alpha and IL-8 and higher for stromal cell-derived factor-1 (SDF-1) in uncultured placental explants from HIV-1-infected women. In the HIV-1-infected group, but not in the non-infected group, the secretion levels of TNF-alpha and IL-8, as well as their mRNA expression levels, were highly positively correlated; furthermore, their secretion levels were correlated positively with LIF and IL-10 secretion levels. We found no correlation between the cytokine levels and the immunovirological status of the HIV-1-infected mothers or the type or duration of treatment. These results highlight the potential impact of HIV-1 and of the anti-retroviral treatments on the placental cytokines pattern, independently of their anti-viral activity.

Down modulation of TNF-alpha mRNA placental expression by AZT used for the prevention of HIV-1 mother-to-child transmission.

Mechanisms of HIV-1 in utero mother-to-child transmission (MTCT) protection provided by AZT are not completely understood. The placental cytokine network is involved in the control of HIV-1 in utero transmission but the effect of AZT on this network is unknown. To evaluate the effects of AZT on placental cytokine expression, the chorionic villi from HIV-1 uninfected women term placentae were cultured with 0, 100, and 2,000 ng/ml AZT. Tissue fragments were harvested at days 1, 4, and 7 to determine the level of cytokine mRNA by real-time RT-PCR. The viability and morphology of the placental histocultures were monitored by the expression of beta-human chorionic gonadotropin (beta-hCG) gene, lipopolysaccharide (LPS) activation, and microscopic examination. AZT at 2,000 ng/ml significantly down-regulated TNF-alpha mRNA expression at day 1 and day 4, but had no effect on beta-hCG, stromal cell-derived factor 1 (SDF-1), and IL-10 gene expression. AZT did not induce any deleterious impact on placental tissue structure. Furthermore, activation of chorionic villi by LPS for 24 h up-regulated IL-10 and TNF-alpha mRNA expression. Down-regulation of TNF-alpha mRNA could represent a mechanism through which AZT can decrease the risk of HIV-1 MTCT, in addition to its direct effect on HIV-1 replication.

Evaluation of the placental environment with a new in vitro model of histocultures of early and term placentae: determination of cytokine and chemokine expression profiles.

We aimed to set up and validate a new in vitro model of placental histocultures, for the evaluation of cytokine and chemokine profiles of the placental environment, over a long culture period. Micro-explant cultures from 6 early and 6 term placentae were set up on collagen sponge gel supports at a liquid/air interface. At various times during culture, we analyzed tissue morphology and cell death by microscopy and quantified beta-hCG production and mRNA levels for beta-hCG and insulin-like 4 (INSL4). Levels of IL-6, LIF, TNF alpha, IL-10, IFN-gamma, IL-16 and RANTES in the medium were measured by ELISA on days 1, 4 and 7 of culture. SDF-1 mRNA expression was determined by real-time PCR at the same time points. Histocultures from early and term placentae remained viable until day 10. High levels of IL-6 and LIF production, low levels of TNF alpha, IL-10 and IFN-gamma production and significant SDF-1 expression were observed. These data indicate that placental histoculture is a suitable and reliable in vitro model for studying the placental environment.

Detectable levels of interleukin-18 in uterine luminal secretions at oocyte retrieval predict failure of the embryo transfer.

BACKGROUND: Most implantation failures after successful in vitro fertilization-embryo transfer (IVF-ET) result from inadequate uterine receptivity. There is currently no way to predict this receptivity. METHODS: We investigated whether the detection of interleukin-(IL)18 by ELISA in uterine luminal secretions might predict implantation failure. Secretions of 133 patients enrolled in our IVF-ET program were sampled by uterine flushing immediately before oocyte retrieval. We assessed the following outcomes: pregnancy rate, multiple pregnancy rate, and implantation rate per embryo transferred. RESULTS: Interleukin-18 was detected in the flushing fluid of 38 patients (28.6%). Although the two groups were comparable for all other characteristics (age, etiology, ovarian reserve, number of embryos transferred, quality of embryos), all outcome variables differed significantly. The pregnancy rate was 37.9% in the IL-18 - ve group and 15% in the IL-18 + ve group, the multiple pregnancy rate 27.7% and 0%, and the implantation rate per embryo transferred 19.4% and 6.7% (all comparisons, P=0.02). Only embryos meeting good quality criteria were transferred to 65 patients: 50 IL-18 - ve and 15 IL-18 + ve. The pregnancy rate was 51% for the IL-18 - ve group and 20% for the IL-18 + ve group, the multiple pregnancy rate 36% and 0.0%, respectively, and the implantation rate 29% and 8.3% (P = 0.02). CONCLUSION: This non-invasive and simple method predicted inadequate uterine receptivity, independent of embryo quality.

Cell-free HIV type 1 infection is restricted in the human trophoblast choriocarcinoma BeWo cell line, even with expression of CD4, CXCR4 and CCR5.

The restriction of cell-free HIV-1 infection has been demonstrated in placental trophoblast choriocarcinoma BeWo cells. We tried to determine the level of the viral replication cycle at which this restriction occurs. BeWo cells produce infectious viruses after transfection with HIV-1 plasmids, independently of viral tropism. CCR5 and CXCR4, but not the CD4 molecule, were detected at the cell surface. We therefore derived CD4-expressing clones from transfected BeWo cells. Cell-free virus infection of these clones resulted in neither virus production nor viral sequence integration, indicating that the restriction occurs before integration of the virus. If we used luciferase reporter viruses pseudotyped with HIV-1 Env R5 and X4 for infection, no luciferase activity was detected, even in the BeWo-CD4+ clone, in contrast to what was observed in VSV-G pseudotyped virus infection. Our results show that infection of trophoblast-derived cells with cell-free virus is at least restricted at the level of entry. Thus, BeWo is an interesting human placental cell line that is resistant to HIV-1, even if CD4, CXCR4, and CCR5 are expressed.

[The impact of stress in the maternofetal relationship: an immunological approach]. / L'impact du stress dans le dialogue materno-foetal: une approche immunologique.

Pregnancy is controlled primarily, though not exclusively, by a delicate equilibrium between locally acting growth factors and cytokines, some under steroid control. The hypothesis considered here is that stress is able to influence the equilibrium between cytokines and thus lead to abortions or implantation failure. We thus detailed the studies on that topic in order to explore the psycho-neuro-immunological mechanisms concerned. The duration of stress, the patient's strategy for coping with this and the social context might be able to produce some opposite immunological effects. Thus, the link between stress and the immunological events induced is complex, and much care is needed for such patients.

Demonstration of the presence of IL-16, IL-17 and IL-18 at the murine fetomaternal interface during murine pregnancy.

PROBLEM: To determine if interleukin-16 (IL-16), IL-17, and IL-18 are present at the murine fetomaternal interface during pregnancy as a first step towards investigating their roles in fetomaternal relationship. METHODS: Expression of IL-16, IL-17, and IL-18, was assessed by immunohistochemistry (IHC) in the BALB/c x BALB/k (H2d x H2k), and the CBA/J x BALB/c non-abortion prone, and CBA/J x DBA/2 abortion prone matings. Enzyme-linked immunosorbent assay (ELISA) were performed for the two latter cytokines to compare local production in the abortion prone CBA/J x DBA/2 versus the non-abortion prone CBA/J x BALB/c matings. RESULTS: Expression of IL-17 was borderline. The anti-IL-16 staining specifically localized in the uterine stroma and glandular epithelium and was rather low in the placenta. IL-18 staining started in the peri-implantation uterus in the basal proliferative stroma, and was also traced, although weaker, in the glandular epithelium. In the immediate post-implantation period, a weak stromal staining persisted but there was a strong labeling of the ectoplacental cone. Interestingly, when the ectoplacental cone differentiates into placenta having a major histocompatibility complex (MHC) class I + spongiotrophoblast and a (MHC class I-) labyrinth, a very strong transient labeling of uterine natural killer (u-NK) cells was found. Later in gestation, IL-18 was also produced by giant cell and spongiotrophoblast. Finally, we compared by ELISA the production of IL-17/-18 in CBA/J x DBA/2 and CBA/J x BALB/c matings. We detected significantly more IL-18 in the non-abortion prone combination decidua or placenta. CONCLUSION: The three cytokines IL-16, IL-17, and IL-18 were detected at the fetomaternal interface with a tissue specific, stage-dependent distribution. The predominance of IL-18 secretion in the non-resorption prone matings lead us to question the general validity of the classical T-helper (Th)1/2 paradigm.

Involvement of cytokines in eating disorders: a critical review of the human literature.

A number of findings from clinical and animal studies indicate that pro-inflammatory cytokines may play roles in eating disorders. The measurement of pro-inflammatory cytokines (IL-1, IL-6, TNFalpha), which are known to decrease food intake, provides highly variable data from which firm conclusions cannot be drawn. In most of the longitudinal studies where pro-inflammatory cytokines have been shown to be impaired in anorexia or bulimia nervosa, a return to normal values was observed after renutrition. However these findings do not exclude the possibility that pro-inflammatory cytokines might be overproduced in specific brain areas and act locally without concomitantly increased serum or immune production. It was also pointed out that the production of the major type-1 cytokines (especially IL-2) was depressed in anorexia nervosa. It remains unclear whether this is due to undernutrition or to a specific underlying cause common to eating disorders. The impaired cytokine profile observed in eating disorders could be related to several factors including impaired nutrition, psychopathological and neuroendocrine factors. More particular attention should be devoted to the deregulation of the anti/pro-inflammatory balance. Deregulation of the cytokine network may be responsible for medical complications in eating disorder patients who are afflicted with chronic underweight.