45 research outputs found

    Single-cell reconstruction of follicular remodeling in the human adult ovary

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    The ovary is perhaps the most dynamic organ in the human body, only rivaled by the uterus. The molecular mechanisms that regulate follicular growth and regression, ensuring ovarian tissue homeostasis, remain elusive. We have performed single-cell RNA-sequencing using human adult ovaries to provide a map of the molecular signature of growing and regressing follicular populations. We have identified different types of granulosa and theca cells and detected local production of components of the complement system by (atretic) theca cells and stromal cells. We also have detected a mixture of adaptive and innate immune cells, as well as several types of endothelial and smooth muscle cells to aid the remodeling process. Our results highlight the relevance of mapping whole adult organs at the single-cell level and reflect ongoing efforts to map the human body. The association between complement system and follicular remodeling may provide key insights in reproductive biology and (in) fertility

    Comparing the cumulative live birth rate of cleavage-stage versus blastocyst-stage embryo transfers between IVF cycles:a study protocol for a multicentre randomised controlled superiority trial (the ToF trial)

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    Introduction In vitro fertilisation (IVF) has evolved as an intervention of choice to help couples with infertility to conceive. In the last decade, a strategy change in the day of embryo transfer has been developed. Many IVF centres choose nowadays to transfer at later stages of embryo development, for example, transferring embryos at blastocyst stage instead of cleavage stage. However, it still is not known which embryo transfer policy in IVF is more efficient in terms of cumulative live birth rate (cLBR), following a fresh and the subsequent frozen-thawed transfers after one oocyte retrieval. Furthermore, studies reporting on obstetric and neonatal outcomes from both transfer policies are limited. Methods and analysis We have set up a multicentre randomised superiority trial in the Netherlands, named the Three or Fivetrial. We plan to include 1200 women with an indication for IVF with at least four embryos available on day 2 after the oocyte retrieval. Women are randomly allocated to either (1) control group: embryo transfer on day 3 and cryopreservation of supernumerary good-quality embryos on day 3 or 4, or (2) intervention group: embryo transfer on day 5 and cryopreservation of supernumerary good-quality embryos on day 5 or 6. The primary outcome is the cLBR per oocyte retrieval. Secondary outcomes include LBR following fresh transfer, multiple pregnancy rate and time until pregnancy leading a live birth. We will also assess the obstetric and neonatal outcomes, costs and patients' treatment burden. Ethics and dissemination The study protocol has been approved by the Central Committee on Research involving Human Subjects in the Netherlands in June 2018 (CCMO NL 64060.000.18). The results of this trial will be submitted for publication in international peer-reviewed and in open access journals. Trial registration number Netherlands Trial Register (NL 6857)

    Progression to CMV end-organ disease in HIV-1-infected individuals despite abundance of highly differentiated CMV-specific CD8(+) T-cells

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    Since CMV-specific T-cells have been shown to generally express an advanced state of differentiation, we investigated whether these mature CMV-specific T-cells are sustained in HIV-infected patients, who are not treated with HAART, receive no CMV medication, but do progress to AIDS with CMV end-organ disease (AIDS-CMV). CD8(+) and CD4(+) T-cell phenotype was studied in these patients in comparison with long-term asymptomatic HIV-infected individuals, progressors to AIDS without CMV end-organ disease as well as CMV-seropositive HIV-negative controls. CMV-specific CD8(+) T-cells from progressors to AIDS-CMV expressed markers typical of highly differentiated effector T-cells, being CCR7(-), CD27(-) CD45RO(+/-), with high CD57 expression and increased Ki67 expression, compatible with functional effector cell capabilities. In addition, CD4(+) T-cells with the characteristic CD27(-)CD28(-) phenotype previously shown to be induced by CMV infection specifically, were found in very high numbers in the HIV+ individuals, but the highest in progressors to AIDS-CMV just before onset of disease. Also the normally rare CD45RO(-)CD27(-)CD4(+) subset increased significantly, whereas the CD45RO(-)CD27(+)CD4(+) subset decreased. Our data show that in patients progressing to AIDS-CMV, CMV-specific CD8(+) T-cells have expanded and are fully differentiated to mature functional effector T-cells. These cells are not protective apparently, but may contribute to tissue-associated immunopathology characteristic of these clinical conditions. (c) 2004 Elsevier B.V. All rights reserve

    Eliciting dose is associated with tolerance development in peanut and cow's milk allergic children

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    Background: Tolerance development rates differ between food allergies. Almost all previous studies have not used the gold standard method, the double-blind, placebo-controlled food challenge (DBPCFC), which may affect the reported prevalence rates. Little is known about the association of the eliciting dose (ED) obtained during the initial DBPCFC with later tolerance development. Methods: This was a retrospective, tertiary care study of children who had a positive DBPCFC to either peanut, milk or egg, and at least one follow-up food challenge (open or DBPCFC) with the same food. The association between ED and negative (tolerant) follow-up food challenge outcome was analyzed by logistic regression, with adjustment for confounders. Suspected confounders were initial DBPCFC test characteristics, atopic comorbidities and serum specific IgE (sIgE) levels. Results: In 47 peanut allergic children, tolerance developed in 27.7% (median follow-up duration of 43 months). In 80 milk (follow-up 23 months) and 55 egg (follow-up 37 months) allergic children, tolerance developed in 55.0% and 65.5%. The ED obtained during the initial DBPCFC was significantly associated with tolerance development in peanut and milk allergy, but not in egg allergy. Conclusion: Approximately 1 out of 4 children with DBPCFC confirmed peanut allergy developed tolerance, compared to more than half of the children with milk or egg allergy, respectively. Tolerance development in peanut and milk allergy is significantly associated with ED at initial DBPCFC

    Signal inhibitory receptor on leukocytes-1 recognizes bacterial and endogenous amphipathic α-helical peptides

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    Signal inhibitory receptor on leukocytes-1 (SIRL-1) is a negative regulator of myeloid cell function and dampens antimicrobial responses. We here show that different species of the genus Staphylococcus secrete SIRL-1-engaging factors. By screening a library of single-gene transposon mutants in Staphylococcus aureus, we identified these factors as phenol-soluble modulins (PSMs). PSMs are amphipathic α-helical peptides involved in multiple aspects of staphylococcal virulence and physiology. They are cytotoxic and activate the chemotactic formyl peptide receptor 2 (FPR2) on immune cells. Human cathelicidin LL-37 is also an amphipathic α-helical peptide with antimicrobial and chemotactic activities, structurally and functionally similar to α-type PSMs. We demonstrate that α-type PSMs from multiple staphylococcal species as well as human cathelicidin LL-37 activate SIRL-1, suggesting that SIRL-1 recognizes α-helical peptides with an amphipathic arrangement of hydrophobicity, although we were not able to show direct binding to SIRL-1. Upon rational peptide design, we identified artificial peptides in which the capacity to ligate SIRL-1 is segregated from cytotoxic and FPR2-activating properties, allowing specific engagement of SIRL-1. In conclusion, we propose staphylococcal PSMs and human LL-37 as a potential new class of natural ligands for SIRL-1

    Immunological Analysis of Treatment Interruption After Early Highly Active Antiretroviral Therapy

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    We longitudinally evaluated HIV-specific T-cell immunity after discontinuation of highly active antiretroviral therapy (HAART). After treatment interruption (TI), some individuals could maintain a low plasma viral load ( 50,000 copies/mL). Before HAART was initiated, plasma viral load was similar. After TI, the numbers of CD8(+) T cells increased more in individuals without viral control, whereas individuals maintaining a low viral load showed a more pronounced increase in HIV-specific CD8(+) T-cell numbers. No differences were seen in the number or percentage of cytokine-producing HIV-1-specific CD4(+) T cells, or in proliferative capacity of T cells. Four weeks after TI, the magnitude of the total HIV-1-specific CD8(+) T-cell response (IFN-gamma(+) and/or IL-2(+) and/or CD107a(+)) was significantly higher in individuals maintaining viral control. Degranulation contributed more to the overall CD8(+) T-cell response than cytokine production. Whether increased T-cell functionality is a cause or consequence of low viral load remains to be elucidate
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