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See detailNew pre-conception immune biomarkers for clinical practice: interleukin-18, interleukin-15 and TWEAK on the endometrial side, G-CSF on the follicular side.
Lédée, Nathalie; Petitbarat, M.; Rahmati, M. et al

in Journal of Reproductive Immunology (2011), 88(2), 118-123

dentification 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 ... [more ▼]

dentification 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. [less ▲]

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See detailTWEAK Appears as a Modulator of Endometrial IL-18 Related Cytotoxic Activity of Uterine Natural Killers
Petitbarat, M.; Rahmati, M.; Sérazin, V. et al

in PLoS ONE (2011), 6(1), 14497

BACKGROUND: TWEAK (Tumor necrosis factor like WEAK inducer of apoptosis) is highly expressed by different immune cells and triggers multiple cellular responses, including control of angiogenesis. Our ... [more ▼]

BACKGROUND: TWEAK (Tumor necrosis factor like WEAK inducer of apoptosis) is highly expressed by different immune cells and triggers multiple cellular responses, including control of angiogenesis. Our objective was to investigate its role in the human endometrium during the implantation window, using an ex-vivo endometrial microhistoculture model. Indeed, previous results suggested that basic TWEAK expression influences the IL-18 related uNK recruitment and local cytotoxicity. METHODOLOGY/PRINCIPAL FINDINGS: Endometrial biopsies were performed 7 to 9 days after the ovulation surge of women in monitored natural cycles. Biopsies were cut in micro-pieces and cultured on collagen sponge with appropriate medium. Morphology, functionality and cell death were analysed at different time of the culture. We used this ex vivo model to study mRNA expressions of NKp46 (a uNK cytotoxic receptor) and TGF-beta1 (protein which regulates uNK cytokine production) after adjunction of excess of recombinant IL-18 and either recombinant TWEAK or its antibody. NKp46 protein expression was also detailed by immunohistochemistry in selected patients with high basic mRNA level of IL-18 and either low or high mRNA level of TWEAK. The NKp46 immunostaining was stronger in patients with an IL-18 over-expression and a low TWEAK expression, when compared with patients with both IL-18 and TWEAK high expressions. We did not observe any difference for TWEAK expression when recombinant protein IL-18 or its antibody was added, or conversely, for IL-18 expression when TWEAK or its antibody was added in the culture medium. In a pro-inflammatory environment (obtained by an excess of IL-18), inhibition of TWEAK was able to increase significantly NKp46 and TGF-beta1 mRNA expressions. CONCLUSIONS/SIGNIFICANCE: TWEAK doesn't act on IL-18 expression but seems to control IL-18 related cytotoxicity on uNK cells when IL-18 is over-expressed. Thus, TWEAK appears as a crucial physiological modulator to prevent endometrial uNK cytotoxicity in human. [less ▲]

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See detailDébats actuels sur l'immunologie de la prééclampsie. Comptes rendus du sixième colloque international de La Réunion (décembre 2008)
Robillard, P. Y.; Chaouat, G.; Le Bouteiller, P. et al

in Gynécologie Obstétrique & Fertilité (2009), 37(6), 570-8

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 ... [more ▼]

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. [less ▲]

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See detailSoluble HLA-G in IVF/ICSI embryo culture supernatants does not always predict implantation success: a multicentre study.
Tabiasco, J.; PERRIER d'HAUTERIVE, Sophie ULg; Thonon, Fabienne ULg et al

in Reproductive Biomedicine Online (2009), 18(3), 374-81

Several reports have described an association between the presence of soluble human leukocyte antigen G (sHLA-G) in human embryo culture supernatants (ES) and implantation success. However, not all ... [more ▼]

Several reports have described an association between the presence of soluble human leukocyte antigen G (sHLA-G) in human embryo culture supernatants (ES) and implantation success. However, not all studies agree with these findings. To further document this debate, a multicentre blinded study was performed to investigate, on a large number of IVF ES and ICSI ES, whether sHLA-G is a useful criterion for embryo selection before transfer. A total of 1405 ES from 355 patients were collected from three assisted reproductive technique (ART) centres and evaluated for their sHLA-G content in a single laboratory, using a chemiluminescence enzyme-linked immunosorbent assay. In only one centre was a significant association between sHLA-G-positive ES and successful implantation established (P = 0.0379), whereas no such association was observed in the other centres. It was found that the percentages and concentrations of sHLA-G-positive ES varied between centres, depending on culture media and ART conditions. The percentage of sHLA-G-positive ES was significantly higher in IVF ES than ICSI ES (P < 0.001 and P < 0.01 for two centres). These data demonstrate that substantial variations of sHLA-G content in ES occur between different ART centres, highlighting the influence of several technical parameters that differ from one centre to another. [less ▲]

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See detailCytokines and chemokines in follicular fluids and potential of the corresponding embryo: the role of granulocyte colony-stimulating fator
Lédée, Nathalie ULg; Lombroso, R.; Lombardelli, L. et al

in Human Reproduction (2008), 23(9), 2001-9

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 ... [more ▼]

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- ) 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. [less ▲]

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See detailSignificance of soluble HLA-G detection in follicular fluids and embryo supernatants in IVF/ICSI cycles
Lédée, Nathalie ULg; Thonon, Fabienne ULg; PERRIER d'HAUTERIVE, Sophie ULg et al

in Journal of Reproductive Immunology (2007, August), 75(1), 11

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