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TO THE EDITOR, Dermatomyositis (DM) is a chronic inflammatory and autoimmune disorder belonging to the idiopathic inflammatory myopathies affecting primarily skin and muscle with variable extent. Disease mechanism comprehension is growing, with a pivotal role of both the innate and adaptive immune system and involvement of both cellular and humoral actors (Nagaraju and Lundberg, 2011). [...]

Reproductive immunology applies general immunology principles to specialised targets, reproduction and development. The involvement of colony-stimulating factors (CSFs) in reproduction illustrates this. The CSF family includes CSF-1 or macrophage CSF (M-CSF), CSF-2 or granulocyte macrophage CSF (GM-CSF), and CSF-3 or granulocyte CSF (G-CSF). Each member has a specific localisation and timed expression in the reproductive tract with specific functions involving them in ovulation, embryo implantation, placentation and further embryonic development. They are used in reproductive medicine, either as biomarkers of oocyte quality and competence (follicular G-CSF), or to supplement embryo culture media with human recombinant GM-CSF, or they are used as an innovative therapy by using human recombinant G-CSF for infertile patients. Given fundamental considerations on CSFs and their strong implication in reproduction, this review aimed to detail the current knowledge for each member of the family to improve our understanding of their implication in the maternal–foetal cytokinic dialogue and in possibly preventing reproductive disorders.

In the introduction, we briefly recall old but classic evidence that there is no tolerance to paternal alloantigens in a first pregnancy. Therefore, we performed small- and large-scale microarrays in CBA × DBA/2 and CBA × BALB/c combinations, recently described as a murine model for preeclampsia. Our results are in line with other data suggesting a very early deregulation of local immune vascular events rather than a break of immune tolerance. Other data presented at the Tioman 2010 Preeclampsia Workshop supporting this hypothesis are briefly summarised, as well as indications and caveats from a recent human microarray on implantation failure and recurrent pregnancy loss.

Citation Chaouat G, Petitbarat M, Dubanchet S, Rahmati M, Ledee N. Tolerance to the Foetal Allograft? Am J Reprod Immunol 2010 In this review, we will detail the concept of tolerance and its history in reproductive immunology. We will then consider whether it applies to the foetal–maternal relationship and discuss the mechanisms involved in non-rejection of the foeto-placental unit.

Udgivelsesdato: 2009-Nov This paper reports a summary of our comparative analysis of the uterine expression of interleukin-23 (IL-23), IL-27 and TWEAK in the CBA/J femalexDBA/2 male mouse mating combination, a model of immune-mediated early pregnancy loss. Compared with the MHC-identical CBA/JxBALB/c mating combination, which yields successful pregnancies, immunohistochemistry and qPCR in uterine tissue showed an immediate post-mating IL-27 hyper-expression after mating with DBA/2 males. Intra-uterine TWEAK expression was present in females mated with DBA/2 or Balb/c males from days 0.5 to 4.5 post-coitum (pc), peaking on day 0.5 pc together with uterine TNFalpha. In uteri of DBA/2 mated mice, TWEAK declined to almost undetectable levels on days 6.5-9.5 pc, a steeper drop than in BALB/c mated mice where TWEAK remained detectable. In both mating combinations, neutralisation of TWEAK by antibodies increased resorption rates, but surprisingly, so did IL-27 neutralisation. The complement regulator mannan binding lectin-A (MBL-A), but not MBL-C, was present on day 4.5 pc especially after mating with DBA/2 males. High levels of MBL are present in the uterine luminal fluid of sterile women, and possible functions for TWEAK and MBL in human implantation are indicated by their protein and mRNA expression in uterine biopsies from infertile and fertile individuals. Consistent with the results in mice, increased MBL expression is linked with pregnancy failure. Serum and uterine VEGF and VEGF receptor levels are also different between fertile and sterile patients. The implications of these findings for utilising the CBA/JxDBA/2 mating combination as an early onset model of preeclampsia are discussed.

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

Problem An important subset of implantation defects/early abortion seems to be linked with a deregulation of the interleukin (IL)-12/IL-15/IL-18 system as well as tumor necrosis factor (TNF)- and natural killer (NK)-controlled/mediated networks at the decidual placental interface, both in case of deficient or excess expression. The presence of TNF in high amounts in the pre/peri-implantation uterus and its pivotal role during pregnancy are difficult to reconcile with its abortive effects in ongoing pregnancy. We therefore searched for regulators of the IL-12/IL-18 family of cytokines as well as for antagonist(s) of TNF with potentially selective effects on implantation. Method of study We first used Swiss mice to verify the presence in the murine reproductive tract of ‘new members’ of the IL-12 family of cytokines, IL-23 and IL-27, as well as of tumor necrosis factor-like WEAK inducer of apoptosis (TWEAK), described as acting with TNF as Yin and Yang of innate immunity in murine placenta/ decidua at days 0–12.5. We then compared expression by RT-PCR in the CBA × DBA/2, and CBA × BALB/c murine mating combinations. Finally, we performed in vivo neutralization experiments of TWEAK and IL-27. Results Immunohistochemistry (IHC) studies showed that IL-23, IL-27, and TWEAK were expressed at the interface. For RT-PCR, IL-23 expression peaked at day 9.5 in the non-aborting mating combination, a peak absent in the aborting one, and thus difficult to explain except by invoking a feed back on EB13 (Epstein–Barr virus-induced gene 3 cytokine). Most important, an immediate post-mating IL-27 hyper expression was seen in the CBA × DBA/2 mating compared to CBA × BALB/c one. The difference in expression resurged and was statistically very significant by days 6.5–9.5, compatible with an early activation of inflammation on day 0.5 which would then peak again in the ‘resorption window’ where takes place the early NK/mph activation described by Baines et al. A significant TWEAK expression was present in both strains from days 0.5 to 4.5 peaking in both cases in the first days when it is known that intra uterine TNF also reaches high levels as a component of post-mating inflammation. However, it was lower from day 1.5 in the abortion-prone CBA × DBA/2 mating combination, and almost absent by days 6.5–9.5 when compared to the non-aborting CBA × BALB/c mating combination. In both mating combinations, neutralization of TWEAK-enhanced resorption rates, but surprisingly so did IL-27 neutralization. Conclusion TWEAK is likely offering protection against the deleterious effects of TNF in implantation explaining embryo survival in a TNF-rich environment, and equal number of implants in both strains. However, there is a clear difference of protection in abortion-prone mating peaking in the abortion/resorption window but starting early, and therefore possible links with the prevention of abortion in CBA × DBA/2 matings by interfering with complement activation as recently described by Girardi et al. are discussed, as well as consequences for our current view of feto-maternal ‘seed and soil’ interplay. The apparently paradoxical effects of IL-27 neutralization are also discussed.

Introduction Uterine receptivity was assessed simultaneously by measurement of vasoactive cytokines possibly involved in development of spiral arteries and by assessment of endometrial and uterine arterial blood flow. The objective was to explore the relationship between cytokine-related dysregulation and endometrial vascularisation in women with repeated implantation failures after in vitro fertilisation embryo transfer (IVF-ET). Materials and methods We studied 40 women with recurrent IVF/ICSI-ET failures, despite replacement of more than 10 embryos of ‘good quality', and 8 fertile controls. Three-dimensional ultrasound with power angiography was performed to record the sub-endometrial vascular flow index (VFI) and uterine artery pulsatility index prior to endometrial biopsy at day 21–23 of a monitored natural cycle. Endometrial IL-18, IL-18BP and IL-15 mRNA expression was assessed by real-time PCR, and the number of CD56 + cells determined by immunochemistry. Results IL-18 and IL-15 mRNA expression was significantly different between the two groups. The range of variation in vascular imaging data was increased in the implantation failure (IF) group. The mRNA ratio for IL-15, but not the other cytokines, correlated with sub-endometrial vascular flow ( r =0.65; p + cells per high-power field ( r =0.41; p =0.005). Both IL-18 and IL-18BP mRNA expression was significantly negatively correlated with mean uterine artery pulsatility index ( r =−0.37 and −0.43; p =0.02 and 0.01, respectively). Conclusion Comprehensive ultrasonographic indicators appear to be related to various mechanisms, including insufficient or excessive uterine NK cell recruitment and inadequate endothelial vascular remodelling. New molecular tools may be useful in providing greater precision of uterine receptivity than ultrasonic indicators alone.

Resume Cet article passe en revue l'evolution des concepts du danger de rejet du fœtus a la vision actuelle d'un role necessaire de l'immunite innee dans l'implantation et de la necessite d'une inflammation, tant pour l'adhesion que l'invasion, mais aussi pour preparer la tolerance ulterieure. Il se termine par un bref apercu sur le role de la cytokine TWEAK et du complement.

The implantation process, currently thought to be the most critical step in achieving a successful early pregnancy, remains one of the most important unsolved processes in reproductive medicine. It depends on uterine-dependent and embryo-specific events, which need to be critically coordinated. Early embryo signaling following a maternal hormonal or cytokine-mediated preparation phase seems to be involved in stages immediately before, during and just after the apposition step to permit adequate proliferation of the stroma. Our objective is to develop guidelines and diagnostic tools pertinent to appreciate uterine receptivity. We will focus our attention on the uterine luminal environment at the time of oocyte retrieval and on the monitoring of the endometrium using three-dimensional ultrasound associated with digital technology and cytokine quantification by real-time PCR during the implantation window in an IVF/ICSI population. There is an accumulating body of data which strongly suggests that both implantation and uterine receptivity are controlled, primarily, though not exclusively, by locally acting growth factors and cytokines, some under steroid control. Some specific cytokines (IL-12, IL-15 and IL-18) in the luminal environment and in the endometrium allow a distinct pattern of abnormal uterine receptivity. The identification of these distinct patterns of abnormal uterine receptivity and of the mechanisms leading to the abnormal angiogenesis before implantation strongly suggest that no single therapeutic scheme can correct all cases of implantation failure and should be adapted for each patient especially in the case of unexplained infertility.

Labeled problem Embryo implantation remains the main limiting factor in assisted reproductive medicine (20% success rate). Methods of study An endometrial immune profiling was performed among 394 women with the previous history of repeated embryo implantation failures (RIF). The endometrial immune profile documented the ratio of IL‐15/Fn‐14 mRNA as a biomarker of uNK cell activation/maturation (together with the uNK cell count) and the IL‐18/TWEAK mRNA ratio as a biomarker of both angiogenesis and the Th1/Th2 balance. According to their profile, we recommended personalized care to counteract the documented dysregulation and assessed its effects by the live birth rate (LBR) for the next embryo transfer. Results Endometrial immune profiles appeared to be dysregulated in 81.7% of the RIF patients compared to control. Overactivation was diagnosed in 56.6% and low activation in 25%. The LBR among these dysregulated/treated patients at the first subsequent embryo transfer was 39.8%. Conclusion Endometrial immune profiling may improve our understanding of RIF and subsequent LBR if treated.

Problem: Cytokines are involved in implantation success and failure. We envisage that they could be similarly involved in pre-eclampsia (PE). Materials and methods: First, we review the primipaternity and primiparity concepts and then why natural killer (NK) cells are involved in implantation. We stress that the common event in all PE is vascular remodelling. Results and conclusion: We conclude that PE could involve cytokine and/or NK dysfunctions, and propose a working hypothesis.

In this paper, we briefly survey the history of concepts in reproductive immunology from antibody-mediated tolerance to the ‘fetal allograft’ to the current concept of an embryo ‘bathing in a sea of cytokines’. We then review the paradigm that ‘allopregnancy is a Th2 phenomenon’ and some of the evidence gained in animals and humans supporting it. We continue by discussing the light it sheds on immunologically caused recurrent abortion, and the present status of the concepts. We next show the limits of the Th1/Th2 paradigm by reviewing the role of ‘inflammatory’ cytokines in implantation (as first seen with leukemia inhibitory factor). We go on to discuss recent data showing that interferon-γ is not solely a ‘bad guy’, e.g. abortifacient as the paradigm would predict, but is needed at low doses for the vascular development and transformation of uterine spiral arteries required for implantation and successful pregnancy. We conclude by discussing the emerging role of NK and IL-12, IL-15, IL-18 tripods and other cytokines in local angiogenesis and tissue remodelling, a series of new data bringing us well beyond the Th1/Th2 paradigm in pregnancy which, in this context, appears now obsolete and an oversimplification, although it has indeed been useful at first. Rather, step-specific events have to be considered and a key role is seen in local tissue remodelling, in which immune cytokines play an important role while not always being secreted by immune cells.

Objective To investigate the endometrial immunohistochemical staining of interleukin (IL)-12 and IL-18 and to quantify the CD56 bright natural killer (NK) cells in relation to Doppler vascular disorders. Design Controlled clinical study. Setting Research unit of a university hospital. Patient(s) Thirty-five women with repeated implantation failure after ET in IVF and 12 fertile control patients. Intervention(s) Ultrasound evaluation and endometrial biopsy on day 20. Main outcome measure(s) The balance between IL-12 and IL-18, the number of NK cells, and the vascular status among fertile and implantation failure patients. Result(s) The control patients displayed normal vascular parameters, a weak anti–IL-12 staining, a consistent moderate stromal anti–IL-18 staining, and fewer than 15 NK cells/field. This pattern was observed among only 17% (6/35) of the implantation failure group. The remaining patients fit into one of two patterns: [1] 37% (13/35) had more than 40 NK cells/field with a strong anti–IL-12 and/or anti–IL-18 staining, and [2] the remaining 46% (16/35) had a marked local depletion of IL-18 and IL-12. Respectively, 85% and 31% of two groups displayed abnormal vascular parameters. Conclusion(s) Distinctions between the different local dysregulations of the cytokine network may provide clues for further exploration and treatment.

Introduction La dermatomyosite (DM) est une maladie auto-immune, atteignant classiquement le muscle et la peau, caracterisee par la presence d’auto-anticorps et une infiltration lymphocytaire des tissus cibles. La DM amyopathique (DMa) est une forme sans atteinte musculaire. L’objectif etait d’etudier les populations lymphocytaires conventionnelles et innees dans le sang et les cytokines pro-inflammatoires seriques des patients ayant une DMa. Materiel et methodes Nous avons inclus 12 patients atteints de DMa, nous presentons les resultats preliminaires sur 6. Les criteres d’inclusion etaient un diagnostic de DMa selon les criteres de l’European NeuroMuscular Center et l’absence de traitement anterieur. Les caracteristiques cliniques (âge, sexe, duree d’evolution, score Cutaneous Dermatomyositis Activity Severity Index, association a une neoplasie et atteinte pulmonaire) et biologiques (anticorps specifiques de myosites, CPK) etaient recueillies. Les sous-populations de lymphocytes T circulants chez les patients ayant une DMa etaient etudies en cytometrie en flux a l’aide de 18 fluorochromes et comparees a 19 donneurs sains. La mesure des cytokines seriques etait faite dans les serums par technique Luminex ® et etait comparee a 14 donneurs sains. Les resultats etaient exprimes en mediane des % pour les populations cellulaires et en mediane des concentrations (pg/mL) pour les cytokines. Le test bilateral de Student etait utilise, significatifs lorsque p Resultats Les patients ayant une DMa avaient une diminution des populations CD3 + CD4 - CD8 − (0,79 vs 1,49, p + CD28 null (78,1 vs 23,3, p + CD26 + et CD3 + CD26 + CD161 + (0,65 vs 7,04, p p p p p Discussion Il s’agit de la premiere etude sur les modifications phenotypiques lymphocytaires T specifique a la DMa. Il s’agit d’un groupe homogene, naif de traitement sans neoplasie associee. Nous confirmons certains resultats trouves chez les patients ayant une DM classique : augmentation des populations CD3 + CD8 + CD28 null et des taux seriques d’IL-6 et d’IL17A, en faveur d’une physiopathologie commune. Nous avons identifie de nouvelles voies immunitaires perturbees, connues dans le lupus ou la polyarthrite rhumatoide : diminution de l’expression du CD26 parmi les lymphocytes CD3 et diminution de la frequence des iNKT. Nous rapportons une augmentation significative de l’IL-10 liee au score d’activite clinique et regressant apres traitement.

Problem: Human in vitro fertilization (IVF) embryo transfer is accompanied by a low implantation rate even after a very successful IVF, and there are a certain number of ‘idiopathic sterilities’ which are due to repeated implantation failures. In the very same vein, the question of improving implantation rates is of prime importance in agricultural research to improve the management of livestock. Pre-implantation prenatal diagnosis cannot be accomplished in individuals who have a high rate of implantation failure, whether women undergoing IVF, or animals, during genetic cloning. Implantation cytokine networks need to be known in such a perspective. Methods: We review the evolution and theories in reproductive immunology, briefly deal with the complexity of implantation as a step by step developmental event, and then present some of our recent data in mice and human. Conclusions: We conclude that the T helper cell type 1/2 (Th1/Th2) paradigm, as useful as it has been to explain pregnancy, is no longer sufficient in view of the emerging complexity of the cytokine network at the materno-fetal interface. This is peculiarly true for implantation, which, as a step by step developmentally regulated process, involving inflammatory molecules, cannot fit into such a scheme.

We restate briefly why we consider that the Th1/Th2 paradigm, as useful as it has been, is now no longer adequate and is obsolete. We take as an example the role of IL-18, abortifacient at high doses but cardinal for the control of natural killer (NK) cell effects on spiral artery remodelling in mice, and likely also in humans. We then describe briefly our recent studies on cytokine defects and implantation failure in humans, a key feature being the link between uterine cytokine dysregulation and abnormal uterine vascular scores. We draw lessons for preeclampsia, and describe features of a model for its immune aetiology.

Objective To assess intrauterine levels of leukemia inhibitory factor (LIF) by uterine flushing at the time of egg retrieval and to confirm that the procedure has no detrimental effect on pregnancy rates. Design Prospective study. Setting Assisted reproductive unit of a university hospital. Patient(s) Uterine flushing was performed in 148 IVF patients. The first 100 patients were compared with a matched control group. Intervention(s) Uterine flushing at the time of egg retrieval. Main outcome measure(s) IVF-ET results, pregnancy rates, and intrauterine LIF levels. Result(s) Pregnancy rates were not different in the group of patients with (27%) or without uterine flushing (28%). Leukemia inhibitory factor was detected in 60 patients (46%). Pregnancy rates did not differ between patients' detectable LIF and those in whom LIF was undetectable. Mean levels of LIF were 30.1 ± 49.3 pg/mL and 28.6 ± 51.2 pg/mL in pregnant and nonpregnant patients respectively. Conclusion(s) The flushing procedure at the time of egg retrieval did not adversely affect pregnancy rates. Leukemia inhibitory factor was detected in 46% of patients at the time of egg retrieval, but no correlation were observed with better pregnancy rates in patients with detectable LIF. Mean LIF levels did not differ in pregnant and nonpregnant women. Access to endoluminal secretions of the endometrium during IVF-ET may represent a new research in human implantation.

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.

PROBLEM: Expression and hormonal regulation of pro-inflammatory cytokines and their role in blastocyst activation and implantation is poorly known. The present study is aimed at analysing the expression and hormonal modulation of two pro-inflammatory cytokines [interleukin-1α (IL-1α) and IL-6] in mouse blastocysts during implantation. METHOD OF STUDY: Blastocyst–uterine interactions are inhibited by progesterone during implantation and subsequent treatment with oestrogen triggers events that allow implantation to begin. Using this delayed implantation mouse model, dormant and activated blastocysts were recovered from mice treated with progesterone alone and progesterone plus oestrogen therapy, respectively. Expression of IL-1α and IL-6 messenger RNA (mRNA) was analysed in normal, dormant and activated blastocysts by in situ hybridization using specific labelled sense and antisense RNA probes, and the protein expression of the same was analysed by immunocytochemistry. RESULTS: In situ hybridization revealed IL-1α and IL-6 mRNA localization in normal, dormant and activated blastocysts and a differential expression was observed in relation to the exposure to progesterone and oestrogen. There was less expression in the dormant blastocysts as compared with the normal and activated ones, and the pattern was similar for both cytokines. Immunocytochemistry also revealed a similar pattern of protein expression to that of the mRNA expression for both the cytokines. CONCLUSIONS: Using a delayed implantation model, we show that mouse blastocysts express both IL-1α and IL-6 mRNA as well as their respective proteins. Both mRNA and the protein levels of IL-1α and IL-6 seem to be hormonally modulated in mouse blastocysts during implantation.

IntroductionRecombinant human Granulocyte-Colony Stimulating Factor (rhG-CSF) supplementation seems to be a promising innovative therapy in reproductive medicine, used in case of recurrent miscarriage, embryo implantation failure or thin endometrium, although its mechanisms of action remain unknown. Our aim was to identify possible endometrial pathways influenced by rhG-CSF.Materials and methodsHypothetical molecular interactions regulated by G-CSF were designed through a previous large scale endometrial microarray study. The variation of endometrial expression of selected target genes was confirmed in control and infertile patients. G-CSF supplementation influence on these targets was tested on an endometrial ex-vivo culture. Middle luteal phase endometrial biopsies were cultured on collagen sponge with or without rhG-CSF supplementation during 3 consecutive days. Variations of endometrial mRNA expression for the selected targets were studied by RT-PCR.ResultsAt the highest dose of rhG-CSF stimulation, the mRNA expression of these selected target genes was significantly increased if compared with their expression without addition of rhG-CSF. The selected targets were G-CSF Receptor (G-CSFR), Integrin alpha-V/beta-3 (ITGB3) implicated in cell migration and embryo implantation, Plasminogen Activator Urokinase Receptor (PLAUR) described as interacting with integrins and implicated in cell migration, Thymidine Phosphorylase (TYMP) implicated in local angiogenesis, CD40 and its ligand CD40L involved in cell proliferation control.ConclusionRhG-CSF seems able to influence endometrial expressions crucial for implantation process involving endometrial vascular remodelling, local immune modulation and cellular adhesion pathways. These variations observed in an ex-vivo model should be tested in-vivo. The strict indications or counter indication of rhG-CSF supplementation in reproductive field are not yet established, while the safety of its administration in early pregnancy on early embryogenesis still needs to be demonstrated. Nevertheless, rhG-CSF appears as a promising therapy in some difficult and unsolved cases of reproductive failure. Indications of pre-conceptual rhG-CSF supplementation may derive from a diagnosed lack of endometrial expression of some target genes.

PROBLEM Implantation of human embryo requires expression of inflammatory cytokines and local attraction of T cells and natural killer (NK) cells. Chemokines are chemoattractants for these cells in classical inflammation. We speculated that they could also be involved in implantation. METHOD OF STUDY We assessed by enzyme-linked immunosorbent assay (ELISA), reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemistry the presence of three classical beta chemokines Macrophage Inflammatory Protein 1 (MIP1)alpha, MIP1beta and Regulated upon activation, normal T cells expressed and secreted (RANTES) in cultures of placental villi or isolated trophoblasts derived from human first trimester and term placenta. RESULTS Explant culture assays were positive for these three chemokines, with important quantitative variations between individuals. Half of the highly purified trophoblasts cultures were found by ELISA and RT-PCR to secrete in vitro MIP1alpha and MIP1beta. RANTES was never detected by ELISA in trophoblasts cultures, albeit we could detect a low amount of messenger RNA. Immunohistochemistry experiments show that Hofbauer cells and the trophoblast layer are a secretion site of MIP1beta in term placenta, and that cytotrophoblasts are able to secrete this chemokine in early placenta. CONCLUSION Human placenta is a site of secretion of chemokines that could be involved in establishment of pregnancy.

BACKGROUND: The possibility that a specific cytokine profile could be detected in the ovaries of patients with polycystic ovarian syndrome (PCOS) was investigated. METHOD: Enzyme-linked immunosorbent assay (ELISA) or bioassays were used to assess the concentrations of leukaemia inhibitory factor (LIF), tumour necrosis factor, interleukin 11, gamma interferon, progesterone and oestradiol in follicular fluids from preovulatory follicles collected after ovarian stimulation from 15 PCOS patients, 15 infertile control patients with regular cycles, and 8 oocyte donors. RESULTS: LIF and progesterone concentrations were significantly lower in the follicular fluid of PCOS patients (LIF median: 265 pg/ml) compared with controls (LIF median: 816 pg/ml); LIF and progesterone follicular fluid concentrations were correlated (r = 0.720, P = 0.0001). The LH/FSH ratio was negatively correlated with LIF concentrations (r = - 0.714, P = 0.0075). Although the PCOS and control patients did not differ significantly in age, ovarian reserve or IVF indication, the implantation rate was significantly lower among the women with PCOS (IR = 9 versus 21%, P = < 0.01). CONCLUSION: The specific cytokine profile of the PCOS patients is probably related to the lower implantation rate since follicular fluid LIF appears to function as an embryotrophic agent.

Resume Les auteurs font le point sur l'immunoregulation des reactions maternelles a l'egard du fœtus (reaction quasi inflammatoire initiale, role des cellules NK, de HLA-G, activation T et NK, cytokines) et proposent de nouvelles pistes.

PROBLEM: To understand the mechanisms preventing and/or facilitating maternofetal transmission of human immunodeficiency virus (HIV)-1 across the placenta during pregnancy. METHODS OF STUDY: Current experimental data were reviewed. RESULTS AND CONCLUSIONS: The data about the production of cytokines by placental cells and explants, taken together with information indicating selective passage of certain HIV-1 variants across the placental trophoblast, suggest an intricate regulatory network operating at the fetomaternal interface. The data show a differential differentiation of early and late trophoblasts, as far as HIV entry routes are concerned. We believe this explains the relative predominance of the early infection window, as far as in utero infection is concerned. Whether such a differentiation state can be transiently induced on term placental trophoblasts by several differentiation agents, including cytokines, is being investigated. Whatever the results may be, it is obvious that infection of placental cells is an excellent model of passage infection by HIV of/through a mucosal barrier.

Patients with a history of repeated and unexplained implantation failure after IVF-embryo transfer and a high uterine natural killer cell count during estrogen-progestin treatment may benefit from controlled natural IVF-ET.

The degree of susceptibility of human hepatoma (HepG2) cells to direct hepatitis B virus (HBV) infection remains unknown. We previously observed a low level of Dane particle production and viral DNA replication after in vitro infection of HepG2 cells with serum-derived HBV. However, this culture system appeared to be affected by variations as human hepatocyte cultures. In the present study, HBV infection of HepG2 cells led to a significant increase in the secretion of three envelope antigens (HBsAg, preS2Ag and preS1Ag) at 4 days post-infection, and Northern blot analysis revealed the presence of both preS1 (2.6 kb) and preS2/S (2.2 kb) transcripts. Expression of preS1Ag and the corresponding viral RNA became undetectable on 21 days post-infection whereas the 2.2 kb RNA species persisted and was associated with secretion of subviral HBs particles expressing preS2-epitopes and banding between 30 and 35% sucrose. At 35 days post-infection (fifth passage), a sudden high level production of HBsAg and preS1Ag was observed, followed by a massive cell death (90%). A stable HBsAg-producing HepG2 cell line, designated HepG2-BV3, grew out of the surviving cells. HepG2-BV3 cells could integrate HBV DNA sequences and produce the three HBV surface antigens. Treatment with dexamethasone increased the HBsAg and preS1Ag secretion. Such a HBsAg-producing HepG2 cell line obtained by in vitro HBV infection seems to mimick events that occur in the naturally occurring persistent chronic infection, and therefore may be an efficient in vitro model for studying the contribution of viral integration in the dysregulation of HBV and liver-specific genes expression.

BackgroundTWEAK (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 findingsEndometrial 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/significanceTWEAK 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.

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Introduction: Girardi and Salmon highlighted the role of complement in early gestation failures in mice. We wanted to identify the pathway of its early activation in the murine natural immune resorbtion model she used. Methods: We monitored the protein and mRNAs expression of MBL-A and C, C3, at different days of gestation, in the uteri of either an “abortive murine combination” DBA/2-mated CBA/J females or a non abortive control mating and established MBL KO congenics on CBA/J background. Results: BALB/c-mated CBA/J females. We also comparatively quantified their expression by RT-PCR. The immunohistochemistry experiments revealed the presence of these (3) proteins and a differential expression of MBL-A between CBA/J × BALB/c and CBA/J × DBA/2 pregnancies while MBL-C was undetectable. However our results of RT-PCR revealed a very low or null local expression of MBL-A and C RNAs and no change in C3 RNA expression in the two combinations. We suggest that MBL-A, and C3 are produced elsewhere but activated locally. To verify the role of MBL, we established at INRA animal facility from breeders from Charles River Iffac Credo France on CBA/J background MBL-A, MBL-C, and MBL-A + C double congenics KO strain starting from MBL KO mice provided by Drs. Jensenius and Thiel Denmark. Albeit the results are still preliminary, at the 5th generation (96.88% of the genome of the KO is already CBA/J), our first results reveal a significant decrease of resorption (using chi-squared test with correction for small samples) in MBL-A KO CBA/J × DBA/2 compared with CBA/J × DBA/2 mating (4.3%, e.g. the incompressible rate of pregnancy loss due to chromosomal anomalies induced foetal demises in mice) versus 12.2% (the usual abortion rate seen in conventional but very clean breeding conditions as is the case at INRA). Depending on breeding and backcrosses, data at the 6th or 7th generation, and with more mice, will eventually be presented. Published data about MBL in human will also be discussed. Conclusions: These results reconcile the “danger” signals and the classical abortive cytokinic pathways, and have profound implications both in murine models and human clinics, which will also be discussed.

In this review, we will detail the concept of tolerance and its history in reproductive immunology. We will then consider whether it applies to the foetal-maternal relationship and discuss the mechanisms involved in non-rejection of the foeto-placental unit.

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Tumor necrosis factor-like weak inducer of apoptosis (TWEAK) could play a role in the regulation of interleukin (IL)-15 and IL-18, cytokines crucial for angiogenesis and uterine natural killer (uNK) cell recruitment during embryo implantation. We therefore confirmed the endometrial presence of TWEAK/fibroblast growth factor inducible-14 (Fn-14) and documented simultaneously the cytotoxic KIR receptor (NKp46) of uNK cells in the human endometrium while TWEAK, Fn-14, IL-15, and IL-18 mRNA were quantified by real-time polymerase chain reaction in relation to the recruitment of CD56+ cells among fertile control women and patients who had failed to implant after assisted reproduction treatment.

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.

An in vitro system for production of hepatitis B virus (HBV) was established by infection of human hepatoma (HepG2) cells. HBV particles obtained from the serum of a chronic hepatitis B surface antigen (subtype ad) carrier were used to inoculate HepG2 cells. HBV envelope and core proteins were synthesized de novo by the infected cells and secreted into the medium 3 to 6 days postinfection. Viral covalently closed circular DNA, the putative template for viral RNA transcription, accumulated in the cells with increasing time postinfection. The HBV-infected HepG2 cells were maintained for several months (HepG2-BV cell line) and continued producing viral antigens. Both HBV DNA replicative intermediates and major HBV transcripts were identified in HepG2-BV cells. Complete HBV particles, which contain HBV DNA and DNA polymerase activity and express the three antigenic specificities of the envelope (hepatitis B surface antigen, pre-S2, and pre-S1), were released into the culture supernatant. Thus, successful in vitro infection of transformed human hepatocytes raising stable HBV-producing cells was achieved for the first time. This strongly suggests that HepG2 cells have a receptor(s) for virus attachment and penetration. Such a system represents a significant advance for the study of HBV-target cell interactions as the early events of HBV infection.

The expression of the preS1 antigen of hepatitis B virus in sera from chronic HBsAg carriers was studied using a specific monoclonal antibody F35.25 in an original, double-immunoradiometric assay. The antibody F35.25 recognized an epitope located between amino-acid residues 32 and 53 on the preS1 sequence of the large HBsAg protein. This domain could be involved in the recognition of hepatitis B virus by hepatocyte receptors. PreS1 antigen detection by monoclonal antibody F35.25 closely correlated with the presence of complete virions in the serum of HBsAg carriers, as demonstrated by ultracentrifugation-gradient experiments and electron-microscopical examination. Of the 19 HBsAg carriers with chronic liver disease, preS1 antigen was detected in 17 (90%): all of the 11 HBeAg- and hepatitis B virus-DNA--positive cases (group 1) and six of eight anti-HBe--positive cases with low levels of hepatitis B virus replication (group 2). PreS1 antigen/HBsAg ratios parallel to preS1 antigen titers were significantly higher in the HBeAg-positive group (34% and 1:10(6] than in the anti-HBe--positive group (18% and 1:10(2]. In contrast, preS1 antigen was not detected in 18 (90%) of the 20 HBsAg healthy carriers positive for anti-HBe and negative for serum hepatitis B virus-DNA (group 3). Our results show that in chronic HBsAg carriers the serum expression of preS1 antigen correlates well with the level of hepatitis B virus replication (serum hepatitis B virus-DNA and/or liver HBcAg) and that it may be useful in assessing the clinical importance of the chronic viral infection.

Cytokines are obviously very important in an established pregnancy, but what about human embryo implantation?Literature review.We first discuss the necessity and limits of animal models, and then review the few cytokines which have been demonstrated by knock-out methods to be absolutely necessary for embryo implantation using in animal models. We then review what is known or discussed about the role of other cytokines as deduced from quantitative and/or qualitative dysregulation in animals and in humans.Cytokines are indeed involved in implantation as they are in ongoing pregnancy and delivery. Relevance to infertility and recurrent pregnancy loss is discussed.

In a brief introduction, this review states why the presence of immune cells at the interface poses problems for an immunologist (Medawar paradigm). Different types of placentation are then discussed, and the various interactions with leukocytes, the extreme being with the equids where a certain degree of 'attack' is often seen. The limits of animal models when dealing with the human situation are emphasized. It is then stated why the various phases of pregnancy are different, and an analysis made of the cellular movements at the implantation, peri-implantation, immediate post-implantation and resorption windows in rodents. Details of the cellular components involved are given, as are hints for the human situation. The Th1/Th2 paradigm is described, with clinical examples, and its limits. Thus, the newly appraised dual role of natural killer (NK) cells is discussed, with examples in rodents and in humans (pre-eclampsia, implantation failure, abortion systems). Clinical data on the IL-12 /IL-18/NK tripod and implantation failure in humans are detailed.

This review introduces the field of cytokines and implantation and then recalls the specialized role of the uterus and the notion of the 'implantation window'. The role of inflammatory and angiogenic cytokines is presented, as well as the involvement of cytokines such as -interferons in corpus luteum maintenance in non-chorionic gonadotrophin-producing species. -Interferons are reviewed, before dealing with the more in depth analysis of cytokine networks in the pre- and peri-implantation uterus. The emerging involvement of cytokines in controlling uterine vascularization angiogenesis is reviewed, with emphasis on NK activating factors.

This review introduces the field of cytokines and implantation and then recalls the specialized role of the uterus and the notion of the ‘implantation window’. The role of inflammatory and angiogenic cytokines is presented, as well as the involvement of cytokines such as -interferons in corpus luteum maintenance in non-chorionic gonadotrophin-producing species. -Interferons are reviewed, before dealing with the more in depth analysis of cytokine networks in the pre- and peri-implantation uterus. The emerging involvement of cytokines in controlling uterine vascularization angiogenesis is reviewed, with emphasis on NK activating factors.

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.