Prostaglandin E2 synthesis and suppression of fibroblast proliferation by alveolar epithelial cells is cyclooxygenase-2-dependent

Alveolar epithelial cells (AECs) may influence neighboring fibroblasts by the elaboration of prostaglandin E(2) (PGE(2)). This prostanoid can be synthesized via "constitutive" cyclooxygenase (COX)-1 and "inducible" COX-2 enzyme isoforms. We compared AECs isolated from wild-type (WT), COX-1 knockout (KO), and COX-2 KO mice to determine the contribution of COX isoforms to AEC PGE(2) synthesis and capacity for suppression of fibroblast proliferation in co-cultures. WT AECs constitutively expressed both COX-1 and COX-2 isoforms by immunoblot analysis. COX-1 KO cells and WT cells comparably augmented PGE(2) synthesis following incubation with lipopolysaccharide or interleukin-1, whereas COX-2 KO cells were unable to do so. Surprisingly, however, constitutive generation of PGE(2) was also dramatically reduced only in COX-2 KO cells. When co-cultured with WT murine lung fibroblasts, AECs from WT and COX-1 KO animals suppressed serum-induced fibroblast proliferation, whereas COX-2-deficient AECs caused a modest enhancement in fibroblast proliferation. These results indicate that PGE(2) synthetic capacity in AECs is predominantly COX-2-dependent under both basal and stimulated conditions. They also demonstrate conclusively that AECs can modulate fibroblast function by the elaboration of suppressive prostanoids. These alterations in AEC phenotype likely contribute to the propensity for pulmonary fibrosis observed in COX-2-deficient mice.     

Induction of interleukin-12 and gamma interferon requires tumor necrosis factor alpha for protective T1-cell-mediated immunity to pulmonary Cryptococcus neoformans infection

The development of T1-cell-mediated immunity is required to clear a pulmonary Cryptococcus neoformans infection. The objective of these studies was to determine the mechanism by which tumor necrosis factor alpha (TNF-alpha) augments the development of pulmonary T1 immunity to C. neoformans infection. TNF-alpha expression was detected in lavage sample cells at days 2, 3, and 7 following C. neoformans infection. The numbers of CFU in the lung were not different between control and anti-TNF-alpha-treated mice at any time point examined during the afferent phase of the response (days 0 to 7). However, neutralization of TNF-alpha prevented the initiation of pulmonary clearance during the efferent phase of the response (day 14). Administration of anti-TNF-alpha monoclonal antibody (day 0) diminished the lung levels of TNF-alpha, interleukin-12 (IL-12), and gamma interferon (IFN-gamma) induced by C. neoformans at day 7 postinfection. Neutralization of TNF-alpha (day 0) also altered the IFN-gamma/IL-4 ratio in the lung-associated lymph nodes at day 7 following C. neoformans infection. Anti-TNF-alpha-treated mice developed a pulmonary eosinophilia at day 14 postinfection. Consistent with the pulmonary eosinophilia, anti-TNF-alpha-treated mice exhibited elevated serum immunoglobulin E and inhibition of the anticryptococcal delayed-type hypersensitivity response, indicating a shift toward a T2 response. Neutralization of IL-12 also prevented lung leukocyte production of IFN-gamma in response to the infection. These findings demonstrate that afferent-phase TNF-alpha production is essential for the induction of IL-12 and IFN-gamma and neutralization of early TNF-alpha results in a T2 shift of the T1/T2 balance of antifungal immunity.     

Transient neutralization of tumor necrosis factor alpha can produce a chronic fungal infection in an immunocompetent host: potential role of immature dendritic cells

The mechanisms underlying induction of immune dysregulation and chronic fungal infection by a transient tumor necrosis factor alpha (TNF-alpha) deficiency remain to be defined. The objective of our studies was to determine the potential contribution of neutropenia and immature dendritic cells to the immune deviation. Administration of an anti-TNF-alpha monoclonal antibody at day 0 neutralized TNF-alpha only during the first week of a pulmonary Cryptococcus neoformans infection. Transient neutralization of TNF-alpha resulted in transient depression of interleukin-12 (IL-12), monocyte chemotactic protein 1 (MCP-1), and gamma interferon (IFN-gamma) production but permanently impaired long-term clearance of the infection from the lungs even after the levels of these cytokines increased and a vigorous inflammatory response developed. Early neutrophil recruitment was defective in the absence of TNF-alpha. However, as demonstrated by neutrophil depletion studies, this did not account for the decrease in IL-12 and IFN-gamma levels and did not play a role in establishing chronic pulmonary cryptococcal infection. Transient TNF-alpha neutralization also produced a deficiency in CD11c(+) MHC II(+) cells and IL-12 in the lymph nodes, potentially implicating a defect in mature dendritic cell trafficking. Transfer of cryptococcal antigen-pulsed immature dendritic cells into naive mice prior to intratracheal challenge resulted in the development of a nonprotective immune response to C. neoformans that was similar to that observed in anti-TNF-alpha-treated mice (increased IL-4, IL-5, and IL-10 levels, pulmonary eosinophilia, and decreased clearance). Thus, stimulation of an antifungal response by immature dendritic cells can result in an immune deviation similar to that produced by transient TNF-alpha deficiency, identifying a new mechanism by which a chronic fungal infection can occur in an immunocompetent host.     

Integration of stakeholder engagement from development to dissemination in genomic medicine research: Approaches and outcomes from the CSER Consortium

PurposeThere is a critical need for genomic medicine research that reflects and benefits socioeconomically and ancestrally diverse populations. However, disparities in research populations persist, highlighting that traditional study designs and materials may be insufficient or inaccessible to all groups. New approaches can be gained through collaborations with patient/community stakeholders. Although some benefits of stakeholder engagement are recognized, routine incorporation into the design and implementation of genomics research has yet to be realized.MethodsThe National Institutes of Health–funded Clinical Sequencing Evidence-Generating Research (CSER) consortium required stakeholder engagement as a dedicated project component. Each CSER project planned and carried out stakeholder engagement activities with differing goals and expected outcomes. Examples were curated from each project to highlight engagement strategies and outcomes throughout the research lifecycle from development through dissemination.ResultsProjects tailored strategies to individual study needs, logistical constraints, and other challenges. Lessons learned include starting early with engagement efforts across project stakeholder groups and planned flexibility to enable adaptations throughout the project lifecycle.ConclusionEach CSER project used more than 1 approach to engage with relevant stakeholders, resulting in numerous adaptations and tremendous value added throughout the full research lifecycle. Incorporation of community stakeholder insight improves the outcomes and relevance of genomic medicine research.     

Expression of superoxide dismutase and xanthine oxidase in myometrium, fetal membranes and placenta during normal human pregnancy and parturition

Superoxide, an agent which attenuates the half-life of nitric oxide, is metabolized and synthesized by superoxide dismutase (SOD) and xanthine oxidase, respectively. Over the last few years much work has focused on the role of nitric oxide in human parturition. The aim of this study was to determine whether the onset of human parturition is associated with a change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD), manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the uterus. Samples of myometrium, placenta, decidua and fetal membranes were obtained from women before and after the onset of labour at term. Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like immunoreactivity was detected in syncytiotrophoblast cells, villous stromal cells and endothelial cells of blood vessels in the placenta. In the myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial cells and to some vascular smooth muscle cells. In the fetal membranes we observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion, extravillous trophoblast and decidua. There was no difference in SOD enzyme activity or staining intensity for SOD between different cell types before and during labour. Xanthine oxidase immunoreactivity was identified in each of the tissues examined and again there was no difference in immunostaining in tissues obtained from women delivered before or after the onset of labour. These results show that the pregnant uterus is capable of both synthesizing and degrading superoxide and suggest that superoxide dismutase and xanthine oxidase may play a role in the maintenance of uterine quiescence during pregnancy, but not in the initiation of parturition.      

Menstrual cycle and appetite control: implications for weight regulation

Hormonal fluctuations associated with the menstrual cycle influence appetite control and eating behaviour. Energy intake varies during the reproductive cycle in humans and animals, with a periovulatory nadir and a luteal phase peak. Patterns of macronutrient selection show less consistency but a number of studies report carbohydrate cravings in the premenstrual phase, particularly in women with premenstrual syndrome. The cyclical nature of food cravings are frequently, but not invariably, associated with depression. Fluctuations in appetite, cravings and energy intake during the menstrual cycle may occur in parallel with cyclical rhythms in serotonin, which can be accompanied by affective symptoms. The premenstrual phase can be considered as a time when women are especially vulnerable to overconsumption, food craving and depression; this is often associated with low serotonin activity.      

Hydrosalpinges adversely affect markers of endometrial receptivity

While in-vitro fertilization (IVF) was initially developed in women with tubal factor infertility, recent clinical studies have suggested that the presence of hydrosalpinges lowers implantation and pregnancy rates. We postulated that these hydrosalpinges cause impaired endometrial receptivity. A total of 103 women with hydrosalpinges were prospectively evaluated, and compared with 55 infertile and 44 fertile controls. All women had endometrial biopsies during the window of implantation, analysed by conventional histological criteria, and also stained for three integrin markers of endometrial receptivity (alpha1beta1, alpha4beta1 and alpha vbeta3). Women with hydrosalpinges (cases) expressed significantly less of the alpha vbeta3 integrin compared with controls. There was no difference in expression of alpha1beta1 or alpha4beta1 among groups. A significantly greater number of cases had out of phase histology and missing alpha vbeta3 (type I defects) and absent integrin expression despite normal histological maturation (type II) defects, compared with controls. Of 20 women with impaired endometrial receptivity who were also biopsied after hydrosalpinx surgery, 70% demonstrated increased alpha vbeta3 expression. Seventy-seven percent of type I and 57% of type II defects were corrected postoperatively. Using markers of endometrial receptivity, this study demonstrates that inflammatory hydrosalpinges have an adverse effect on endometrial receptivity, which in some cases may be overcome by surgical treatment of the hydrosalpinx.      

Induction of IL-5 expression by IL-2 is resistant to the immunosuppressive agents cyclosporin A and rapamycin

T cell cytokine expression may be induced by the cytokine IL-2 or via the TCR complex. The comparative effects of cytokine- and TCR-mediated signalling on the induction of human IL-5 mRNA were examined. Cytokine mRNA expression was analysed by RT-PCR in fresh peripheral blood mononuclear cells (PBMC) from normal individuals and in populations of activated T lymphocytes, derived from phytohaemagglutinin (PHA)- stimulated PBMC. rIL-2 induced IL-5 expression in PBMC, the kinetics of which were similar to the effects of PHA. rIL-4 induced IL-5 mRNA expression in activated T lymphocytes. IL-5 expression induced by either IL-2 or PHA was completely abolished by the protein synthesis inhibitor cycloheximide. rIL-2-induced IL-5 expression was resistant to cyclosporin A (CsA), whereas IL-5 expression elicited by PHA was inhibited by CsA, at doses as low as 10 ng/ml. Rapamycin (RAP) had no effect on rIL-2-stimulated IL-5 expression, but suppressed IL-5 expression induced by PHA. The inhibitory effect of RAP on PHA-induced IL-5 expression was more apparent at 12 and 24 h after stimulation than at earlier times. The resistance of IL-2 receptor (IL-2R) signalling to CsA and RAP indicates that the IL-2R and the TCR are associated with different pathways regulating IL-5 expression.      

Nationwide Implementation of Hello World: A Dutch Email-Based Health Promotion Program for Pregnant Women

Background

In November 2006, an email-based health promotion program for pregnant women was implemented nationally in the Netherlands. The program consisted of emails containing quizzes with pregnancy-related questions tailored to the number of weeks of pregnancy. Emails were sent out once every 4 weeks, up to a maximum of nine emails.

Objectives

The aims of the study were (1) to assess the recruitment of participants and their representativeness of the Dutch population and (2) to study differences in recruitment, program use, and program appreciation among women with different levels of education.

Methods

Data from 13,946 pregnant women who enrolled during the first year of the program were included. Upon registration, participants were asked how they found out about the program and subsequently received an email questionnaire to assess demographic, lifestyle, and Internet characteristics. Program use was tracked, and participants were classified into five user groups (inactive to very active). Program appreciation (low, intermediate, and high) was assessed twice with an email questionnaire that was sent after the woman had received her third and sixth quiz email. Information about pregnant women and their characteristics was obtained from Dutch registries to assess representativeness of the study population.

Results

About 8% of the pregnant women in the Netherlands enrolled in the program. Immigrants were underrepresented, and women with a low level of education seemed to be slightly underrepresented. Most women knew about the program from a promotional email sent by the organization (32%), followed by the Internet (22%) and midwives (16%). Women with little education were more often inactive users of the program than were highly educated women (15% vs 11%, P < .001), whereas highly educated women were more often very active users compared with women with little education (25% vs 20%, P< .001). However, women with less education were more likely than women with more education to have a high appreciation of the program after receiving three quiz emails (52% vs 44%, P = .001).

Conclusions

In this real-life setting, pregnant women can be reached through an email-based health promotion program. Selective engagement by education level remains a challenge.     

Distinct expression patterns of polycomb oncoproteins and their binding partners during the germinal center reaction

Polycomb group (PcG) genes encode two chromatin-binding protein complexes, the PRC1 and the PRC2 PcG complexes, which are essential for the maintenance of cell identity and play a role in oncogenesis. PcG complexes were recently identified as novel regulators of hematopoiesis, and appear to be expressed in a non-overlapping pattern in resting and mature follicular B cells. Using highly specific antisera in combination with immunohistochemistry and triple immunofluorescence, we investigated the expression pattern of nine human PcG genes in germinal center (GC) B cells and highly purified germinal center B cell subpopulations. PcG proteins were detected in characteristic binding patterns that were not necessarily related to mutually exclusive expression of the two PcG complexes. We conclude that the two PcG complexes are expressed throughout GC development, and that the fine composition of each complex is determined by the differentiation status of the cell. In addition, a subset of dividing cells with a centrocyte CD marker profile was identified that co-expresses core components of the PRC1 and PRC2 complex. We propose that these cells reflect a transitional stage between resting and dividing follicular B lymphocytes, and that they possibly represent the healthy precursors of nodal large B cell lymphomas.