Cell migration is a dynamic process that involves adhesion molecules and the deformation of the moving cell that depends on cytoskeletal remodeling and actin-modulating proteins such as myosins. In ...this work, we analyzed the role of the class I Myosin-1 g (Myo1g) in migratory processes of LPS + IL-4 activated B lymphocytes in vivo and in vitro. In vivo, the absence of Myo1g reduced homing of activated B lymphocytes into the inguinal lymph node. Using microchannel chambers and morphology analysis, we found that the lack of Myo1g caused adhesion and chemotaxis defects. Additionally, deficiency in Myo1g causes flaws in adopting a migratory morphology. Our results highlight the importance of Myo1g during B cell migration.
Purpose
Psychosocial health (PH) and quality of life (QoL) are important health outcomes. We compared PH and QoL of adolescents conceived with intrazytoplasmatic sperm injection (ICSI) and of ...naturally conceived controls. The impact of disclosure of ICSI-conception on QoL and PH was quantified.
Methods
The cross-sectional sample consisted of 545 ICSI-conceived adolescents and 427 unmatched singleton controls aged 14–18 years. Adolescents reported PH with the ‘Strengths and Difficulties Questionnaire’ (low values indicating high PH), and QoL with the KINDL questionnaire (high values indicating high QoL). Because of clustering of multiples within families, adjusted linear regressions with generalized estimating equations were used to compare ICSI- and naturally conceived adolescents. Missing values were treated by multiple imputation. Minimal importance was defined as half a standard deviation.
Results
Both ICSI and control adolescents had high PH (low mean ‘total difficulties’ score: 9 of 40) and high QoL (mean ‘total KINDL’ score: 75 of 100). Differences were generally in favour of the ICSI group. Significant differences occurred for ‘impact of behavioural problems’ (
p
= 0.033), the ‘total KINDL’ score (
p
= 0.021) and the dimensions ‘physical wellbeing’ (
p
= 0.031) and ‘school’ (
p
= 0.005), but all differences were far below minimal importance. About 80% of ICSI adolescents were informed about their mode of conception. PH and QoL were slightly higher in informed adolescents; behavioural difficulties (‘total behavioural problems’ and ‘conduct problems’) were significantly lower (
p
= 0.013 and
p
= 0.003), behavioural strengths (‘prosocial behaviour’) and ‘physical QoL’ significantly higher (
p
= 0.004 and
p
= 0.018), but differences remained clearly below minimal importance.
Conclusions
Our results are reassuring for parents using ICSI and their children. Speaking openly about an ICSI conception in the family may be beneficial.
The intestinal epithelium constitutes a first line of defense of the innate immune system. Epithelial dysfunction is a hallmark of intestinal disorders such as inflammatory bowel diseases (IBDs). The ...actin cytoskeleton controls epithelial barrier integrity but the function of actin regulators such as cortactin is poorly understood. Given that cortactin controls endothelial permeability, we hypothesized that cortactin is also important for epithelial barrier regulation. We found increased permeability in the colon of cortactin-KO mice that was accompanied by reduced levels of ZO-1, claudin-1, and E-cadherin. By contrast, claudin-2 was upregulated. Cortactin deficiency increased RhoA/ROCK1-dependent actomyosin contractility, and inhibition of ROCK1 rescued the barrier defect. Interestingly, cortactin deficiency caused increased epithelial proliferation without affecting apoptosis. KO mice did not develop spontaneous colitis, but were more susceptible to dextran sulfate sodium colitis and showed severe colon tissue damage and edema formation. KO mice with colitis displayed strong mucus deposition and goblet cell depletion. In healthy human colon tissues, cortactin co-localized with ZO-1 at epithelial cell contacts. In IBDs patients, we observed decreased cortactin levels and loss of co-localization with ZO-1. Thus, cortactin is a master regulator of intestinal epithelial barrier integrity in vivo and could serve as a suitable target for pharmacological intervention in IBDs.
Pancreatic ductal adenocarcinoma (PDAC) is one of the most intractable and devastating malignant tumors. Epigenetic modifications such as DNA methylation and histone modification regulate tumor ...initiation and progression. However, the contribution of histone variants in PDAC is unknown. Here, we demonstrated that the histone variant H2A.Z is highly expressed in PDAC cell lines and PDAC patients and that its overexpression correlates with poor prognosis. Moreover, all three H2A.Z isoforms (H2A.Z.1, H2A.Z.2.1, and H2A.Z.2.2) are highly expressed in PDAC cell lines and PDAC patients. Knockdown of these H2A.Z isoforms in PDAC cell lines induces a senescent phenotype, cell cycle arrest in phase G2/M, increased expression of cyclin-dependent kinase inhibitor CDKN2A/p16, SA-β-galactosidase activity and interleukin 8 production. Transcriptome analysis of H2A.Z-depleted PDAC cells showed altered gene expression in fatty acid biosynthesis pathways and those that regulate cell cycle and DNA damage repair. Importantly, depletion of H2A.Z isoforms reduces the tumor size in a mouse xenograft model in vivo and sensitizes PDAC cells to gemcitabine. Overexpression of H2A.Z.1 and H2A.Z.2.1 more than H2A.Z.2.2 partially restores the oncogenic phenotype. Therefore, our data suggest that overexpression of H2A.Z isoforms enables cells to overcome the oncoprotective barrier associated with senescence, favoring PDAC tumor grow and chemoresistance. These results make H2A.Z a potential candidate as a diagnostic biomarker and therapeutic target for PDAC.
Akt activation has been associated with proliferation, differentiation, survival and death of epithelial cells. Phosphorylation of Thr308 of Akt by phosphoinositide-dependent kinase 1 (PDK1) is ...critical for optimal stimulation of its kinase activity. However, the mechanism(s) regulating this process remain elusive. Here, we report that 14-3-3 proteins control Akt Thr308 phosphorylation during intestinal inflammation. Mechanistically, we found that IFNγ and TNFα treatment induce degradation of the PDK1 inhibitor, 14-3-3η, in intestinal epithelial cells. This mechanism requires association of 14-3-3ζ with raptor in a process that triggers autophagy and leads to 14-3-3η degradation. Notably, inhibition of 14-3-3 function by the chemical inhibitor BV02 induces uncontrolled Akt activation, nuclear Akt accumulation and ultimately intestinal epithelial cell death. Our results suggest that 14-3-3 proteins control Akt activation and regulate its biological functions, thereby providing a new mechanistic link between cell survival and apoptosis of intestinal epithelial cells during inflammation.
Objectives Guidelines recommend dual-therapy consisting of a β-lactam/macrolide (BLM) for hospitalized patients with community-acquired pneumonia. Nevertheless, the superiority over ...β-lactam-monotherapy (BL) remains unproven. Methods Analyses from an observational study initiated by the German competence network CAPNETZ were performed. Results One thousand eight hundred and fifty-four patients were treated with either BL (49.0%) or BLM (51.0%). BLM therapy was associated with lower adjusted 14 day mortality odds ratio (OR) 0.53; 95% confidence interval (CI): 0.30–0.94. CRB65, neoplastic disease, age and nursing home residency were confirmed as independent predictors of death. Adjusted 14 day mortality risk was clearly reduced in patients with CRB65 = 2 (n = 411; OR 0.35; CI: 0.12–0.99) and CRB65 ≥ 2 (n = 519; OR 0.42; CI: 0.18–0.997). However, this could not be shown for adjusted 30 day mortality. Patients with CRB65 ≤ 1 showed low mortality (2.1%) without the influence of BLM. BLM therapy was associated with lower adjusted risk of treatment failure at 14 days (n = 1854; OR 0.65; CI: 0.47–0.89) and 30 days (OR 0.69; CI: 0.51–0.94) as well as in the subgroup of patients with CRB65 = 2 and CRB65 ≥ 2. Conclusions This study suggests the superiority of BLM therapy in patients with CRB65 risk classes of 2 or higher on 14 day mortality. BLM therapy was also associated with lower risk of treatment failure.
Epithelial cells lining the intestinal mucosa constitute a selective-semipermeable barrier acting as first line of defense in the organism. The number of those cells remains constant during ...physiological conditions, but disruption of epithelial cell homeostasis has been observed in several pathologies. During colitis, epithelial cell proliferation decreases and cell death augments. The mechanism responsible for these changes remains unknown. Here, we show that the pro-inflammatory cytokine IFNγ contributes to the inhibition of epithelial cell proliferation in intestinal epithelial cells (IECs) by inducing the activation of mTORC1. Activation of mTORC1 in response to IFNγ was detected in IECs present along the crypt axis and in colonic macrophages. mTORC1 inhibition enhances cell proliferation, increases DNA damage in IEC. In macrophages, mTORC1 inhibition strongly reduces the expression of pro-inflammatory markers. As a consequence, mTORC1 inhibition exacerbated disease activity, increased mucosal damage, enhanced ulceration, augmented cell infiltration, decreased survival and stimulated tumor formation in a model of colorectal cancer CRC associated to colitis. Thus, our findings suggest that mTORC1 signaling downstream of IFNγ prevents epithelial DNA damage and cancer development during colitis.
The objective of this case-control study was to identify the main risk factors for community-acquired pneumonia (CAP) in a German adult population. A self-administered questionnaire was given to CAP ...cases provided by the German competence network CAPNETZ and population-based, randomly selected controls (sex- and age-matched). Multivariate analysis showed that in addition to known risk factors such as previous CAP odds ratio (OR) 1·6, 95% confidence interval (CI) 1·3–2·1, more than one respiratory infection during the previous year (OR 3·6, 95% CI 2·9–4·5), chronic pulmonary diseases (OR 2·3, 95% CI 1·7–3·0), number of comorbidities (OR 1·6, 95% CI 1·4–1·9), and number of children in the household (2 children: OR 2·2, 95% CI 1·5–3·4; ⩾3 children: OR 3·2, 95% CI 1·5–7·0) were independent risk factors for CAP. This was pronounced in particular in people aged ⩽65 years. The most likely explanation for this finding is higher exposure to infectious agents.
Summary Objectives Despite strong national and international recommendations on immunization practices, rates for influenza (IV) and pneumococcal vaccinations (PV) are low. We aimed to review ...international immunization rates and to analyze attitudes and beliefs regarding IV and PV. Study design Systematic review. Method The MEDLINE database search comprised articles from 1966 to October 2005. Fourteen surveys evaluating a total number of 49 292 participants in nine different countries were included into the analysis. Results Vaccination rates among risk groups do vary significantly between different countries, reaching highest rates in the USA (IV, 82%; PV, 71%) and lowest in former West-Germany for IV (37%) and in Israel for PV (20%). Recommendations by doctors play a central role in promoting IV and PV. The main reason for not being vaccinated was lack of information. Conclusion Specific strategies targeted at groups are needed to increase the knowledge of IV and PV, and thereby decrease incidences of acute lung diseases.
Guanylate-binding protein-1 (GBP-1) is an interferon inducible large GTPase involved in endothelial cell proliferation and invasion. In this report, expression and function of GBP-1 were investigated ...in vitro in intestinal epithelia after exposure to interferon-gamma and in human colonic mucosa from individuals with inflammatory bowel disease (IBD). Interestingly, in contrast to other epithelia, GBP-1 distributed to the plasma membrane in intestinal epithelial cells where it colocalized with the tight junction protein coxsackie- and adenovirus receptor. In addition, expression of GBP-1 was upregulated in colonic epithelia of individuals with IBD. Downregulation of GBP-1 by siRNA resulted in enhanced permeability that correlated with increased apoptosis. Indeed, inhibition of caspase activity prevented the inhibition of barrier formation induced by the loss of GBP-1. These data suggest that GBP-1 is a novel marker of intestinal mucosal inflammation that may protect against epithelial apoptosis induced by inflammatory cytokines and subsequent loss of barrier function.
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