Health outcomes of children born after IVF/ICSI: a review of current expert opinion and literature.

The Sixth Evian Annual Reproduction (EVAR) Workshop Group Meeting was held to evaluate the impact of IVF/intracytoplasmic sperm injection on the health of assisted-conception children. Epidemiologists, reproductive endocrinologists, embryologists and geneticists presented data from published literature and ongoing research on the incidence of genetic and epigenetic abnormalities and congenital malformations in assisted-conception versus naturally conceived children to reach a consensus on the reasons for potential differences in outcomes between these two groups. IVF-conceived children have lower birthweights and higher peripheral fat, blood pressure and fasting glucose concentrations than controls. Growth, development and cognitive function in assisted-conception children are similar to controls. The absolute risk of imprinting disorders after assisted reproduction is less than 1%. A direct link between assisted reproduction and health-related outcomes in assisted-conception children could not be established. Women undergoing assisted reproduction are often older, increasing the chances of obtaining abnormal gametes that may cause deviations in outcomes between assisted-conception and naturally conceived children. However, after taking into account these factors, it is not clear to what extent poorer outcomes are due to the assisted reproduction procedures themselves. Large-scale, multicentre, prospective epidemiological studies are needed to investigate this further and to confirm long-term health consequences in assisted-conception children. Assisted reproduction treatment is a general term used to describe methods of achieving pregnancy by artificial means and includes IVF and sperm implantation. The effect of assisted reproduction treatment on the health of children born using these artificial methods is not fully understood. In April 2011, fertility research experts met to give presentations based on research in this area and to look carefully at the evidence for the effects of assisted reproduction treatment on children's health. The purpose of this review was to reach an agreement on whether there are differences in the health of assisted-conception children with naturally conceived children. The researchers discovered no increased risk in birth defects in assisted-conception children compared with naturally conceived children. They found that IVF-conceived children have lower birth weights and higher fat under the skin, higher blood pressure and higher fasting glucose concentrations than naturally conceived children; however, growth, development and cognitive function are similar between groups. A very low risk of disorders of genetic control was observed in assisted-conception children. Overall, there did not appear to be a direct link between assisted reproduction treatment and children's health. The researchers concluded that the cause of some differences in the health of children conceived using assisted reproduction treatment may be due to the age of the woman receiving treatment. Large-scale, research studies are needed to study the long-term health of children conceived using assisted reproduction treatment.

B7-DC-Ig enhances vaccine effect by a novel mechanism dependent on PD-1 expression level on T cell subsets.

Programmed death receptor 1 (PD-1) is an important signaling molecule often involved in tumor-mediated suppression of activated immune cells. Binding of this receptor to its ligands, B7-H1 (PD-L1) and B7-DC (PD-L2), attenuates T cell activation, reduces IL-2 and IFN-γ secretion, decreases proliferation and cytotoxicity, and induces apoptosis. B7-DC-Ig is a recombinant protein that binds and targets PD-1. It is composed of an extracellular domain of murine B7-DC fused to the Fc portion of murine IgG2a. In this study, we demonstrate that B7-DC-Ig can enhance the therapeutic efficacy of vaccine when combined with cyclophosphamide. We show that this combination significantly enhances Ag-specific immune responses and leads to complete eradication of established tumors in 60% of mice and that this effect is CD8 dependent. We identified a novel mechanism by which B7-DC-Ig exerts its therapeutic effect that is distinctly different from direct blocking of the PD-L1-PD-1 interaction. In this study, we demonstrate that there are significant differences between levels and timing of surface PD-1 expression on different T cell subsets. We found that these differences play critical roles in anti-tumor immune effect exhibited by B7-DC-Ig through inhibiting proliferation of PD-1(high) CD4 T cells, leading to a significant decrease in the level of these cells, which are enriched for regulatory T cells, within the tumor. In addition, it also leads to a decrease in PD-1(high) CD8 T cells, tipping the balance toward nonexhausted functional PD-1(low) CD8 T cells. We believe that the PD-1 expression level on T cells is a crucial factor that needs to be considered when designing PD-1-targeting immune therapies.

Anti-PD-1 synergizes with cyclophosphamide to induce potent anti-tumor vaccine effects through novel mechanisms.

Programmed death-1 receptor (PD-1) is expressed on T cells following TCR activation. Binding of this receptor to its cognate ligands, programmed death ligand (PDL)-1 and PDL-2, down-regulates signals by the TCR, promoting T-cell anergy and apoptosis, thus leading to immune suppression. Here, we find that using an anti-PD-1 antibody (CT-011) with Treg-cell depletion by low-dose cyclophosphamide (CPM), combined with a tumor vaccine, induces synergistic antigen-specific immune responses and reveals novel activities of each agent in this combination. This strategy led to complete regression of established tumors in a significant percentage of treated animals, with survival prolongation. We show for the first time that combining CT-011 and CPM significantly increases the number of vaccine-induced tumor-infiltrating CD8(+) T cells, with simultaneous decrease in infiltrating Treg cells. Interestingly, we find that CT-011 prolongs Treg-cell inhibition induced by CPM, leading to a sustainable significant synergistic decrease of splenic and tumor-infiltrated Treg cells. Surprisingly, we find that the anti-tumor effect elicited by the combination of CT-011 and CPM is dependent on both CD8(+) and CD4(+) T-cell responses, although the antigen we used is a class I MHC-restricted peptide. Thus, we describe a novel and effective therapeutic approach by combining multiple strategies to target several tumor-mediated immune inhibitory mechanisms.

In vivo iron-sulfur cluster formation.

It has been proposed that iron-sulfur [Fe-S] clusters destined for the maturation of [Fe-S] proteins can be preassembled on a molecular scaffold designated IscU. In the present article, it is shown that production of the intact Azotobacter vinelandii [Fe-S] cluster biosynthetic machinery at levels exceeding the amount required for cellular maturation of [Fe-S] proteins results in the accumulation of: (i) apo-IscU, (ii) an oxygen-labile [2Fe-2S] cluster-loaded form of IscU, and (iii) IscU complexed with the S-delivery protein, IscS. It is suggested that these species represent different stages of the [Fe-S] cluster assembly process. Substitution of the IscU Asp(39) residue by Ala results in the in vivo trapping of a stoichiometric, noncovalent, nondissociating IscU-IscS complex that contains an oxygen-resistant [Fe-S] species. In aggregate, these results validate the scaffold hypothesis for [Fe-S] cluster assembly and indicate that in vivo [Fe-S] cluster formation is a dynamic process that involves the reversible interaction of IscU and IscS.

Genome sequence of Azotobacter vinelandii, an obligate aerobe specialized to support diverse anaerobic metabolic processes.

Azotobacter vinelandii is a soil bacterium related to the Pseudomonas genus that fixes nitrogen under aerobic conditions while simultaneously protecting nitrogenase from oxygen damage. In response to carbon availability, this organism undergoes a simple differentiation process to form cysts that are resistant to drought and other physical and chemical agents. Here we report the complete genome sequence of A. vinelandii DJ, which has a single circular genome of 5,365,318 bp. In order to reconcile an obligate aerobic lifestyle with exquisitely oxygen-sensitive processes, A. vinelandii is specialized in terms of its complement of respiratory proteins. It is able to produce alginate, a polymer that further protects the organism from excess exogenous oxygen, and it has multiple duplications of alginate modification genes, which may alter alginate composition in response to oxygen availability. The genome analysis identified the chromosomal locations of the genes coding for the three known oxygen-sensitive nitrogenases, as well as genes coding for other oxygen-sensitive enzymes, such as carbon monoxide dehydrogenase and formate dehydrogenase. These findings offer new prospects for the wider application of A. vinelandii as a host for the production and characterization of oxygen-sensitive proteins.

Proceedings from the Third National Institutes of Health International Congress on Advances in Uterine Leiomyoma Research: comprehensive review, conference summary and future recommendations.

BACKGROUND Uterine fibroids are the most common gynecologic tumors in women of reproductive age yet the etiology and pathogenesis of these lesions remain poorly understood. Age, African ancestry, nulliparity and obesity have been identified as predisposing factors for uterine fibroids. Symptomatic tumors can cause excessive uterine bleeding, bladder dysfunction and pelvic pain, as well as associated reproductive disorders such as infertility, miscarriage and other adverse pregnancy outcomes. Currently, there are limited noninvasive therapies for fibroids and no early intervention or prevention strategies are readily available. This review summarizes the advances in basic, applied and translational uterine fibroid research, in addition to current and proposed approaches to clinical management as presented at the 'Advances in Uterine Leiomyoma Research: 3rd NIH International Congress'. Congress recommendations and a review of the fibroid literature are also reported. METHODS This review is a report of meeting proceedings, the resulting recommendations and a literature review of the subject. RESULTS The research data presented highlights the complexity of uterine fibroids and the convergence of ethnicity, race, genetics, epigenetics and environmental factors, including lifestyle and possible socioeconomic parameters on disease manifestation. The data presented suggest it is likely that the majority of women with uterine fibroids will have normal pregnancy outcomes; however, additional research is warranted. As an alternative to surgery, an effective long-term medical treatment for uterine fibroids should reduce heavy uterine bleeding and fibroid/uterine volume without excessive side effects. This goal has not been achieved and current treatments reduce symptoms only temporarily; however, a multi-disciplined approach to understanding the molecular origins and pathogenesis of uterine fibroids, as presented in this report, makes our quest for identifying novel targets for noninvasive, possibly nonsystemic and effective long-term treatment very promising. CONCLUSIONS The Congress facilitated the exchange of scientific information among members of the uterine leiomyoma research and health-care communities. While advances in research have deepened our knowledge of the pathobiology of fibroids, their etiology still remains incompletely understood. Further needs exist for determination of risk factors and initiation of preventive measures for fibroids, in addition to continued development of new medical and minimally invasive options for treatment.

The second National Institutes of Health International Congress on advances in uterine leiomyoma research: conference summary and future recommendations.

OBJECTIVE: To summarize the proceedings of the Advances in Uterine Leiomyoma Research: 2nd NIH International Congress, which was convened on February 24-25, 2005 by the Department of Health and Human Services (DHHS), National Institutes of Health (NIH) in Bethesda, Maryland. DESIGN: Scientific information was presented at a 2-day conference, which was a collaborative effort of agencies across the DHHS and members of the academic, clinical, and medical communities involved in uterine leiomyoma research. CONCLUSION(S): The conference brought together scientists in biomedicine, epidemiology, basic research, therapeutics, and translational medicine and fostered an exchange of scientific information among members of the uterine leiomyoma research and health care communities. This document summarizes this exchange and outlines research needs and recommendations for future research directions.

Generation of medial and lateral dorsal body domains by the pannier gene of Drosophila.

The pannier (pnr) gene encodes a GATA transcription factor and acts in several developmental processes in Drosophila, including embryonic dorsal closure, specification of cardiac cells and bristle determination. We show that pnr is expressed in the mediodorsal parts of thoracic and abdominal segments of embryos, larvae and adult flies. Its activity confers cells with specific adhesion properties that make them immiscible with non-expressing cells. Thus there are two genetic domains in the dorsal region of each segment: a medial (MED) region where pnr is expressed and a lateral (LAT) region where it is not. The homeobox gene iroquois (iro) is expressed in the LAT region. These regions are not formed by separate polyclones of cells, but are defined topographically. We show that ectopic pnr in the wing induces MED thoracic development, indicating that pnr specifies the identity of the MED regions. Correspondingly, when pnr is removed from clones of cells in the MED domain, they sort out and apparently adopt the LAT fate. We propose that (1) the subdivision into MED and LAT regions is a general feature of the Drosophila body plan and (2) pnr is the principal gene responsible for this subdivision. We argue that pnr acts like a classical selector gene but differs in that its expression is not propagated through cell divisions.