RESUMO
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.
Assuntos
Fertilização in vitro , Antígenos HLA/análise , Antígenos de Histocompatibilidade Classe I/análise , Injeções de Esperma Intracitoplásmicas , Adulto , Meios de Cultura , Ensaio de Imunoadsorção Enzimática , Antígenos HLA-G , Humanos , LuminescênciaRESUMO
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<0.001). This ratio correlated also with the mean number of CD56(+) 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.
Assuntos
Implantação do Embrião , Endométrio/irrigação sanguínea , Imageamento Tridimensional , Interleucina-15/fisiologia , Interleucina-18/fisiologia , Ultrassom , Adulto , Antígeno CD56/análise , Endométrio/diagnóstico por imagem , Endométrio/imunologia , Feminino , Humanos , Interleucina-15/genética , Interleucina-18/genética , Células Matadoras Naturais/imunologia , Gravidez , UltrassonografiaRESUMO
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.
Assuntos
Citocinas/imunologia , Implantação do Embrião/imunologia , Técnicas de Reprodução Assistida , Útero/imunologia , Feminino , Humanos , Interleucina-15/biossíntese , Interleucina-18/biossíntese , Neovascularização Fisiológica/imunologia , GravidezRESUMO
In our species, reproduction failure rate is high. Clinical evidence is miscarriage where chromosomal origin was largely involved (66% of cases). The development of assisted reproduction techniques made possible to analyse unfertilized oocytes and preimplantation embryos. The results have shown a high rate of chromosome abnormalities before implantation (50%). Two mechanisms were identified which could generate aneuploidy, the meiosis non-disjunction and the premature separation of sister chromatids (PSSC). A FISH analysis of the first polar body, a cell complementary to the oocyte after meiosis, can be performed before intracytoplasmic sperm injection. We studied 2 distinct populations (patients over 38 years old and patients with recurrent implantation failure) and we confirmed that PSSC is the major mechanism linked to advanced maternal age in human.
Assuntos
Aneuploidia , Cromátides/genética , Segregação de Cromossomos , Feminino , Humanos , Idade MaternaRESUMO
The presence of antiphospholipid antibodies is associated with a clinical syndrome characterised by thrombocytopenia, arterial and venous thromboses and recurrent fetal loss. Among theses antibodies currently detectable in laboratory are the lupus anticoagulant and anticardiolipin antibody. The antigens for theses antibodies are phospholipid-binding-proteins (prothrombin and beta 2 glycoprotein I). The exact mechanism of action of antiphospholipid antibodies remains controversal. The pathogenis of pregnancy loss seems related to the increased incidence of placental infraction. In spite of the improvement in our knowledge on the pathogenic mechanisms of the antiphospholipid syndrome, the standard therapy is still based on anti-platelet or anticoagulant drugs, both for vascular and obstetrical problems. Larger prospective clinical studies are needed to validate therapeutic implications.
Assuntos
Aborto Habitual/etiologia , Anticorpos Antifosfolipídeos/sangue , Síndrome Antifosfolipídica/complicações , Síndrome Antifosfolipídica/genética , Síndrome Antifosfolipídica/fisiopatologia , Síndrome Antifosfolipídica/terapia , Feminino , Humanos , GravidezRESUMO
OBJECTIVE: To study the effects of undetectable inhibin B concentrations on the outcomes of testicular sperm extraction (TESE) and of intracytoplasmic sperm injection (ICSI). DESIGN: Retrospective study. SETTING: Obstetrics, gynecology, and reproductive biology departments. PATIENT(S): We carried out TESE on 75 men with nonobstructive azoospermia: 42 men had an inhibin B concentration of
Assuntos
Inibinas/metabolismo , Oligospermia/metabolismo , Injeções de Esperma Intracitoplásmicas/métodos , Testículo/fisiologia , Coleta de Tecidos e Órgãos , Adulto , Biópsia , Criopreservação , Implantação do Embrião/fisiologia , Feminino , Humanos , Masculino , Oligospermia/cirurgia , Gravidez , Estudos Retrospectivos , Preservação do Sêmen , Espermatozoides/metabolismo , Estatísticas não Paramétricas , Testículo/metabolismo , Testículo/cirurgiaRESUMO
PROBLEM: To evaluate the influence of ovarian steroids on IL-18, IL-15 and angiopoietin-2 mRNA expression in the endometrium in the mid luteal phase. METHOD OF STUDY: We quantified IL-18/GAPDH, IL-18 BP/GAPDH, IL-15/GAPDH and angiopoietin-2/GAPDH in the endometrium by quantitative polymerase chain reaction on day 21 of the cycle. We first compared cytokines expression over two natural cycles (n = 15) then between natural and oestrogen-progestin replacement treatment (n = 18). RESULTS: Endometrial IL-18, IL-18 BP, IL-15 and angiopoietin-2 mRNA expression did not change over two natural cycles. Addition of exogenous hormones significantly decreased IL-18 and IL-18 BP mRNA expression but not influence IL-15 or angiopoietin-2 ratios. This was also observed with immunohistochemistry. CONCLUSION: Exogenous oestro-progestative hormones influence endometrial IL-18 system expression involved in angiogenesis and in the uterine natural killer (uNK) cell activation pathway during the implantation process.
Assuntos
Endométrio/efeitos dos fármacos , Endométrio/imunologia , Interleucina-18/genética , Ovário/metabolismo , Esteroides/farmacologia , Angiopoietina-2/genética , Regulação para Baixo/efeitos dos fármacos , Feminino , Humanos , Interleucina-15/genética , Interleucina-18/metabolismo , Gravidez , RNA Mensageiro/metabolismoRESUMO
BACKGROUND: Although intrauterine insemination (IUI) is one of the most common assisted reproductive technology methods in the world, the relative influence of various semen characteristics on the likelihood of a successful outcome is controversial. The aim of our study was to assess the results of IUI as a function of both the number of motile spermatozoa inseminated (NMSI) and the percentage of morphologically normal spermatozoa after preparation. METHODS: This was a retrospective study of 889 couples who underwent 2564 IUI cycles of ovarian stimulation with HMG or recombinant FSH in our centre between January 1991 and December 2000. RESULTS: A total of 331 clinical pregnancies were obtained, for a pregnancy rate/cycle of 12.91%. When the NMSI was < 1 x 10(6), the pregnancy rate/cycle was significantly lower (3.13%) than in any of the subgroups with NMSI > or = 2 x 10(6). Sperm morphology, assessed before or after preparation, was not in itself a significant factor that affected the likelihood of IUI success. Nonetheless, when the post-migration rate of normal sperm was < 30%, the pregnancy rate/cycle was 5.43% when NMSI was < 5 x 10(6) and 18.42% when NMSI was > or = 5 x 10(6) (P = 0.008). Pregnancy rates did not differ significantly according to NMSI when the percentage of normal sperm after preparation was > or = 30%, or according to percentage of normal sperm when the NMSI was > or = 5 x 10(6). CONCLUSIONS: Our results show that a minimum of 5 x 10(6) motile spermatozoa should be inseminated when the normal morphology of the sperm after preparation is < 30%; the quantity compensates at least in part for the defective quality. If this threshold of NMSI cannot be obtained, IVF should be recommended.