No description available.

No description available.

One of the critical periods of time for the establishment of pregnancy is after the onset of implantation but before the establishment of the placenta. In fact, evidence strongly suggests that when abnormalities occur during this period of pregnancy in humans there may be dire consequences such as termination of pregnancy, pre-eclampsia later in pregnancy and small for gestational weight offspring that are less healthy in later life. Therefore, what occurs in the endometrium during the progression of implantation can be crucial for proper fetal development later in pregnancy as well as the health of the offspring. One of the evolving ideas coming from research on the biology of what occurs during early pregnancy is the existence of key bi-directional communications between the conceptus and uterus that may be required for successful pregnancy. Amazingly, some common aspects of this signaling might exist to some extent between mammalian species that have very different modes of implantation and where quite different placentas are formed. Although some conceptus-uterine communication during the progression of decidualization is starting to be worked out, we still have much to learn about the precise details of the entire repertoire of the molecular signals responsible. In the rodent we still have to clearly find and define the biology of important paracrine factors produced by the conceptus that target cells of the endometrium during this period of time when the endometrium is undergoing decidualization. This review focuses on some of the approaches that have been used in the past and what has been learned about the effect of the conceptus on the decidualization of the rodent uterus. Where possible, this is compared and contrasted to what is currently known in other species that exhibit quite different modes of implantation.

Diss. (sammanfattning) Stockholm : Karol. inst., 2006. / Härtill 5 uppsatser.

Background: In the last two decades the discovery of the Toll-Like Receptor (TLR) family in humans revealed the importance of innate immunity in providing host defence against invading pathogens. Moreover, TLRs have a vital role in mediating the interactions between the reproductive and immune systems. Similar to TLRs, (NOD)-like receptors (NLRs); retinoic acid-inducible gene-1, RIG-1-like receptors (RLRs) are also important pattern recognition receptors in the female reproductive system. Successful implantation requires effective reciprocal interactions between receptive endometrium and competent embryo. The endometrial innate immunity during implantation has been intensively investigated. However, little is known about the expression of innate immunity during the early stages of human embryo development. Objective: To investigate the expression of innate immunity molecules during the early stages of human embryo development and to determine the functions of TLRs in blastocysts. Material and methods: The expression of TLRs, a panel of downstream signalling molecules, NLRs, RLRs, inflammatory cytokines, chemokines and the hyaluronic acid system were investigated in the following developmental stages: oocyte, 4- cell, blastomeres, 8- cell, blastocyst, inner cell mass and trophectoderm using Affymetrix Human Genome U133 Plus 2.0 arrays. Microarray data were validated by Q-PCR. TLR function in human blastocysts was investigated by treating day five blastocysts with TLR3 or TLR5 specific ligands; Poly (I:C) and flagellin respectively, for 24 hours. The culture media was analysed for elevated cytokine and chemokine levels using cytometric bead array. Results: TLRs, NLRs, RLRs, TLR downstream signalling molecules, cytokines and chemokines involved during implantation event and the hyaluronic system were all found to be positively expressed in the early stages of human embryo development. The expression levels of the above molecules were generally moderate to low (CT 24-34) and varied across the embryonic developmental stages. Stimulation of TLR3 and TLR5 in day 5 blastocysts produced cytokines and chemokines. In addition, there were alterations in gene expression patterns in the Poly (I:C) and flagellin treated blastocysts in comparison to the untreated blastocysts. Conclusion: The varied expression levels of the investigated molecules involved in early embryonic developmental suggests a potential role for these molecules in early pregnancy loss and implantation failure. Specifically, the relationship between the level of TLR expression, function and embryo quality is worth investigating in the future as a potential marker for embryo competence.

Neste estudo foi analisada a expressão gênica e protéica, uterina e embrionária da quimiocina Ccl25 e de seu receptor Ccr9 nas fases iniciais da implantação embrionária (dias 3,5, 4,5, 5,5 e 7,5 de gestação). Por meio de reações imunohistoquímicas e de citometria de fluxo, foram identificadas as populações celulares envolvidas nesta expressão. Também, foram realizados ensaios de quimiotaxia com o silenciamento da expressão de Ccl25 (ODNs-Antisense) nas células trofoblásticas, para a avaliação das atividades desta quimocina. Nossos resultados sugerem o estabelecimento de uma comunicação embrião (células trofoblásticas) - endométrio (células do sistema immunológico), via Ccl25/Ccr9. Esses achados são relevantes para a compreensão das interações blastocisto/sistema immunológico materno no estabelecimento dos mecanismos imunoreguladores durante a implantação embrionária. / In this study, we analyzed the gene and protein, uterine and embryonic expression of Ccl25 chemokine and its receptor Ccr9 in early stages of embryo implantation (days 3.5, 4.5, 5.5 and 7.5 of gestation). By using immunohistochemistry and flow cytometric assays, cell populations involved in this expression were identified. In addition, chemotaxis assays were also performed after silencing of Ccl25 (ODNs-antisense) in trophoblast cells. . Our results suggest the establishment of an endometrium (immune cells) - embryo (trophoblast cells) dialogue via Ccl25/CCR9. These findings are relevant for understanding the interactions between blastocyst and maternal immune system in the establishment of immunoregulatory mechanisms during implantation.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2009. / Härtill 4 uppsatser.

No description available.

Thesis (Ph.D.). / Written for the Dept. of Experimental Medicine. Title from title page of PDF (viewed 2009/06/09). Includes bibliographical references.

Neste estudo foi analisada a expressão gênica e protéica, uterina e embrionária da quimiocina Ccl25 e de seu receptor Ccr9 nas fases iniciais da implantação embrionária (dias 3,5, 4,5, 5,5 e 7,5 de gestação). Por meio de reações imunohistoquímicas e de citometria de fluxo, foram identificadas as populações celulares envolvidas nesta expressão. Também, foram realizados ensaios de quimiotaxia com o silenciamento da expressão de Ccl25 (ODNs-Antisense) nas células trofoblásticas, para a avaliação das atividades desta quimocina. Nossos resultados sugerem o estabelecimento de uma comunicação embrião (células trofoblásticas) - endométrio (células do sistema immunológico), via Ccl25/Ccr9. Esses achados são relevantes para a compreensão das interações blastocisto/sistema immunológico materno no estabelecimento dos mecanismos imunoreguladores durante a implantação embrionária. / In this study, we analyzed the gene and protein, uterine and embryonic expression of Ccl25 chemokine and its receptor Ccr9 in early stages of embryo implantation (days 3.5, 4.5, 5.5 and 7.5 of gestation). By using immunohistochemistry and flow cytometric assays, cell populations involved in this expression were identified. In addition, chemotaxis assays were also performed after silencing of Ccl25 (ODNs-antisense) in trophoblast cells. . Our results suggest the establishment of an endometrium (immune cells) - embryo (trophoblast cells) dialogue via Ccl25/CCR9. These findings are relevant for understanding the interactions between blastocyst and maternal immune system in the establishment of immunoregulatory mechanisms during implantation.