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Aminoglycosides are an important class of antibiotics that play a critical role in the treatment of life-threatening infections, but their use is limited by their toxicity. In fact, gentamicin causes severe nephrotoxicity in 17% of hospitalized patients. The kidney proximal tubule is particularly vulnerable to drug-induced nephrotoxicity due to its role in drug transport. In this work, we developed a perfused vascularized model of human kidney tubuloids integrated with tissue-embedded microsensors that track the metabolic dynamics of aminoglycoside-induced renal toxicity in real time. Our model shows that gentamicin disrupts proximal tubule polarity at concentrations 20-fold below its TC

Prostate cancer is the most commonly diagnosed type of cancer in men, and there is no available cure for patients with advanced disease. In vitro model systems are urgently required to permit the study of human prostate cell differentiation and malignant transformation. Unfortunately, human prostate cells are particularly difficult to convert into continuously growing cultures. We report here the successful immortalization without viral oncogenes of prostate epithelial cells and, for the first time, prostate stromal cells. These cells exhibit a significant pattern of authentic prostate-specific features. In particular, the epithelial cell culture is able to differentiate into glandular buds that closely resemble the structures formed by primary prostate epithelial cells. The stromal cells have typical characteristics of prostate smooth muscle cells. These immortalized cultures may serve as a unique experimental platform to permit several research directions, including the study of cell-cell interactions in an authentic prostate microenvironment, prostate cell differentiation, and most significantly, the complex multistep process leading to prostate cell transformation. (Cancer Res 2006; 66(7): 3531-40)

Supplementary Figure Legend from hTERT-Immortalized Prostate Epithelial and Stromal-Derived Cells: an Authentic In vitro Model for Differentiation and Carcinogenesis

Supplementary Figure S1 from hTERT-Immortalized Prostate Epithelial and Stromal-Derived Cells: an Authentic In vitro Model for Differentiation and Carcinogenesis

Supplementary Materials & Methods from hTERT-Immortalized Prostate Epithelial and Stromal-Derived Cells: an Authentic In vitro Model for Differentiation and Carcinogenesis

Background:Viral infection is associated with a significant rewire of the host metabolic pathways, presenting attractive metabolic targets for intervention.Methods:We chart the metabolic response of lung epithelial cells to SARS-CoV-2 infection in primary cultures and COVID-19 patient samples and perform in vitro metabolism-focused drug screen on primary lung epithelial cells infected with different strains of the virus. We perform observational analysis of Israeli patients hospitalized due to COVID-19 and comparative epidemiological analysis from cohorts in Italy and the Veteran’s Health Administration in the United States. In addition, we perform a prospective non-randomized interventional open-label study in which 15 patients hospitalized with severe COVID-19 were given 145 mg/day of nanocrystallized fenofibrate added to the standard of care.Results:SARS-CoV-2 infection produced transcriptional changes associated with increased glycolysis and lipid accumulation. Metabolism-focused drug screen showed that fenofibrate reversed lipid accumulation and blocked SARS-CoV-2 replication through a PPARα-dependent mechanism in both alpha and delta variants. Analysis of 3233 Israeli patients hospitalized due to COVID-19 supported in vitro findings. Patients taking fibrates showed significantly lower markers of immunoinflammation and faster recovery. Additional corroboration was received by comparative epidemiological analysis from cohorts in Europe and the United States. A subsequent prospective non-randomized interventional open-label study was carried out on 15 patients hospitalized with severe COVID-19. The patients were treated with 145 mg/day of nanocrystallized fenofibrate in addition to standard-of-care. Patients receiving fenofibrate demonstrated a rapid reduction in inflammation and a significantly faster recovery compared to patients admitted during the same period.Conclusions:Taken together, our data suggest that pharmacological modulation of PPARα should be strongly considered as a potential therapeutic approach for SARS-CoV-2 infection and emphasizes the need to complete the study of fenofibrate in large randomized controlled clinical trials.Funding:Funding was provided by European Research Council Consolidator Grants OCLD (project no. 681870) and generous gifts from the Nikoh Foundation and the Sam and Rina Frankel Foundation (YN). The interventional study was supported by Abbott (project FENOC0003).Clinical trial number:NCT04661930.

Variants of concern (VOC) of SARS-CoV2 and waning immunity pose a serious global problem. Overall, vaccination and prior infection provide significant protection, but some individuals remain susceptible to infection and severe disease. Rigorously identifying correlates of protection (COP) is necessary to identify these susceptible populations. We conducted a multicenter prospective study assessing the association between serological profiles and the risk for SARS-CoV-2 infection, comparing those vaccinated with three to four doses of Pfizer BNT162b2 vaccine. We identified several IgG and IgA binding markers that were COPs. The strongest COP was reduced IgG levels to RBD mutants and IgA levels to VOCs (three-dose-group HR=6.34, p=0.008; four-dose-group HR=8.14, p=0.018). Most importantly, we identified a subset of vaccinated individuals with low antibody levels that generated a significant boost in neutralizing antibody titers after a fourth dose, but were still at significantly increased susceptibility to infection.

Variants of concern (VOC) of SARS-CoV2 and waning immunity pose a serious global problem. Overall, vaccination and prior infection appear to provide significant protection to the majority of individuals, but some remain susceptible to infection and severe disease. Rigorously identifying a broad spectrum of correlates of protection (COP) is necessary to identify these susceptible populations. The extent to which additional booster doses provide protection is also poorly understood. To address this need, we conducted a multicenter prospective study assessing the association between serological profiles and the risk for SARS-CoV-2 infection, comparing those vaccinated with three to four doses of Pfizer BNT162b2 vaccine. Of 608 healthy adults, 365 received three doses and 243 received four doses. During the first 90 days of followup, 239 (39%) were infected, of whom 165/365 (45%) received 3 doses and 74/243 (30%) four doses. We found that the fourth dose elicited a significant rise in antibody binding and neutralizing titers against multiple variants, and reduced the risk of symptomatic infection by 37% [95% I, 15% - 54%]. We identified several parameters based on IgG and IgA binding that were COPs. The strongest association with infection risk was reduced IgG levels to RBD mutants and IgA levels to VOCs, which was a COP in the three-dose group (HR=6.34, p=0.008) and in the four-dose group (HR=8.14, p=0.018). A combination of two commercially available ELISA assays were also associated with protection in both groups (HR = 1.84, p = 0.002; HR = 2.01, p = 0.025, respectively). Most importantly, we identified a subset of individuals with low antibody levels after three doses of vaccine that responded with a significant boost in neutralizing antibody titers after a fourth dose, but were still at significantly increased susceptibility to infection when compared to those who had pre-existing high levels of neutralizing antibodies. Thus, we identify a highly susceptible population that remains susceptible despite apparent responsiveness to vaccines. Further, we develop several specific and sensitive COPs that show dramatic effect sizes and may be utilized to identify individuals most at risk from future exposures.

Comment in: DePICting T cell-APC crosstalk in cancer. Zhang T, Dong C. Nat Cancer. 2022 Mar;3(3):265-267. doi: 10.1038/s43018-022-00345-6. PMID: 35352059 No abstract available.; International audience; Despite their key regulatory role and therapeutic potency, the molecular signatures of interactions between T cells and antigen-presenting myeloid cells within the tumor microenvironment remain poorly characterized. Here, we systematically characterize these interactions using RNA sequencing of physically interacting cells (PIC-seq) and find that CD4+PD-1+CXCL13+ T cells are a major interacting hub with antigen-presenting cells in the tumor microenvironment of human non-small cell lung carcinoma. We define this clonally expanded, tumor-specific and conserved T-cell subset as T-helper tumor (Tht) cells. Reconstitution of Tht cells in vitro and in an ovalbumin-specific αβ TCR CD4+ T-cell mouse model, shows that the Tht program is primed in tumor-draining lymph nodes by dendritic cells presenting tumor antigens, and that their function is important for harnessing the antitumor response of anti-PD-1 treatment. Our molecular and functional findings support the modulation of Tht-dendritic cell interaction checkpoints as a major interventional strategy in immunotherapy.

Acute myeloid leukemia (AML) is one of the deadliest hematological malignancies without effective treatment for most patients. Vitamin D derivatives (VDDs) - active metabolites 1α,25-dihydroxyvitamin D2 (1,25D2) and 1α,25-dihydroxyvitamin D3 (1,25D3) and their analogs - are differentiation-inducing agents which have potential for the therapy of AML. However, calcemic toxicity of VDDs limits their clinical use at doses effective against cancer cells in vivo. Here, we demonstrate that in AML cell cultures, moderate pro-differentiation effects of low concentrations of VDDs can be synergistically enhanced by structurally distinct compounds known to activate the transcription factor Nuclear Factor (Erythroid-derived 2)-Like 2 (NFE2L2 or Nrf2). Particularly, dimethyl fumarate (DMF), which is clinically approved for the treatment of multiple sclerosis and psoriasis, strongly cooperated with 1,25D3, PRI-5100 (19-nor-1,25D2; paricalcitol) and PRI-5202 (a double-point modified 19-nor analog of 1,25D2). The pro-differentiation synergy between VDDs (1,25D3 or PRI-5202) and Nrf2 activators (DMF, tert-butylhydroquinone or carnosic acid) was associated with a cooperative upregulation of the protein levels of the vitamin D receptor (VDR) and Nrf2 as well as increased mRNA expression of their respective target genes. These data support the notion that VDDs and Nrf2 activators synergize in inducing myeloid cell differentiation through the cooperative activation of the VDR and Nrf2/antioxidant response element signaling pathways. We have previously reported that PRI-5202 is more potent by approximately two orders of magnitude than 1,25D3 as a differentiation inducer in AML cell lines. In this study, we found that PRI-5202 was also at least 5-fold less calcemic in healthy mice compared to both its direct precursor PRI-1907 and 1,25D3. In addition, PRI-5202 was remarkably more resistant against degradation by the human 25-hydroxyvitamin D3-24-hydroxylase than both 1,25D2 and 1,25D3. Importantly, using a xenograft mouse model we demonstrated that co-administration of PRI-5202 and DMF resulted in a marked cooperative inhibition of human AML tumor growth without inducing treatment toxicity. Collectively, our findings provide a rationale for clinical testing of low-toxic VDD/DMF combinations as a novel approach for differentiation therapy of AML.

We aimed to compare the reliability of laboratory blood tests using 2 sampling methods, via a peripheral venous catheter (PVC) vs direct venipuncture stab (DVS), we evaluated the effect of time elapsed since PVC insertion, PVC diameter, and administration of saline and/or antibiotic infusion through PVC on the blood test results. A prospective comparative study was conducted between May 2018 and July 2019. Patients aged ≥ 18 years and admitted to our department with a 20G/22G PVC inserted within the last 24 hours were enrolled. Blood samples were collected from each participant in the morning, and a second sample was drawn using PVC. Dependent variables included the percentage of hemolysis, failure rate, complete blood count, biochemical testing parameters, and coagulation functions. A total of 211 patients participated in the study. In total, 237 blood tests were conducted, of which 167 were performed on day 1 and the remaining on day 2, with a second blood sample collected from 26 patients on day 2. Twenty-one participants received 22G PVC, and 23 participants received active infusion. No significant differences were found in failure rates when each subgroup was compared with the primary day 1 group. The intraclass correlation coefficient indicated significant correlations among all the indices in all groups. Both blood sampling methods (PVC and direct venipuncture) can be used interchangeably for routine laboratory tests on days 1 and 2 after PVC insertion using 20G/22G PVC or infused PVC.

International audience; Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are prevalent liver conditions that underlie the development of life-threatening cirrhosis, liver failure and liver cancer. Chronic necro-inflammation is a critical factor in development of NASH, yet the cellular and molecular mechanisms of immune dysregulation in this disease are poorly understood. Here, using single-cell transcriptomic analysis, we comprehensively profiled the immune composition of the mouse liver during NASH. We identified a significant pathology-associated increase in hepatic conventional dendritic cells (cDCs) and further defined their source as NASH-induced boost in cycling of cDC progenitors in the bone marrow. Analysis of blood and liver from patients on the NAFLD/NASH spectrum showed that type 1 cDCs (cDC1) were more abundant and activated in disease. Sequencing of physically interacting cDC-T cell pairs from liver-draining lymph nodes revealed that cDCs in NASH promote inflammatory T cell reprogramming, previously associated with NASH worsening. Finally, depletion of cDC1 in XCR1DTA mice or using anti-XCL1-blocking antibody attenuated liver pathology in NASH mouse models. Overall, our study provides a comprehensive characterization of cDC biology in NASH and identifies XCR1+ cDC1 as an important driver of liver pathology.

Despite their key regulatory role and therapeutic potency, the molecular signatures of interactions between T cells and antigen-presenting myeloid cells within the tumor microenvironment remain poorly characterized. Here, we systematically characterize these interactions using RNA sequencing of physically interacting cells (PIC-seq) and find that CD4

We found that acute insult to the central nervous system induces the formation of lymphocyte aggregates reminiscent of tertiary lymphoid structures within the spinal cord meninges. Unlike draining CNS-cervical lymph nodes, meningeal lymphocytes are locally activated during neuro-inflammtion and neurodegeneration., Tertiary lymphoid structures (TLS) are organized aggregates of B and T cells formed ectopically during different stages of life in response to inflammation, infection, or cancer. Here, we describe formation of structures reminiscent of TLS in the spinal cord meninges under several central nervous system (CNS) pathologies. After acute spinal cord injury, B and T lymphocytes locally aggregate within the meninges to form TLS-like structures, and continue to accumulate during the late phase of the response to the injury, with a negative impact on subsequent pathological conditions, such as experimental autoimmune encephalomyelitis. Using a chronic model of spinal cord pathology, the mSOD1 mouse model of amyotrophic lateral sclerosis, we further showed by single-cell RNA-sequencing that a meningeal lymphocyte niche forms, with a unique organization and activation state, including accumulation of pre-B cells in the spinal cord meninges. Such a response was not found in the CNS-draining cervical lymph nodes. The present findings suggest that a special immune response develops in the meninges during various neurological pathologies in the CNS, a possible reflection of its immune privileged nature.

Viruses are a constant threat to global health as highlighted by the current COVID-19 pandemic. Currently, lack of data underlying how the human host interacts with viruses, including the SARS-CoV-2 virus, limits effective therapeutic intervention. We introduce Viral-Track, a computational method that globally scans unmapped scRNA-seq data for the presence of viral RNA, enabling transcriptional cell sorting of infected versus bystander cells. We demonstrate the sensitivity and specificity of Viral-Track to systematically detect viruses from multiple models of infection, including hepatitis B virus in an unsupervised manner. Applying Viral-Track to Bronchoalveloar-Lavage samples from severe and mild COVID-19 patients reveals a dramatic impact of the virus on the immune system of severe patients compared to mild cases. Viral-Track detects an unexpected co-infection of the human MetaPneumoVirus, present mainly in monocytes perturbed in type-I IFN-signaling. Viral-Track provides a robust technology for dissecting the mechanisms of viral-infection and pathology., Highlights Viral-track: a computational framework to analyze host-viral infection maps Viral-track sorts infected from bystander cells and reveals virus-induced expression SARS-CoV-2 infects epithelial cells and alters immune landscape in severe patients Coinfection of SARS-Cov-2 and hMPV affects monocytes and dampen interferon response, A computational framework that allows for the identification and characterizaton of virus-infected cells as well as bystander cell responses reveals how SARS-CoV-2 alters the immune responses of patients.

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are prevalent liver conditions that underlie the development of life-threatening cirrhosis, liver failure and liver cancer. Chronic necro-inflammation is a critical factor in development of NASH, yet the cellular and molecular mechanisms of immune dysregulation in this disease are poorly understood. Here, using single-cell transcriptomic analysis, we comprehensively profiled the immune composition of the mouse liver during NASH. We identified a significant pathology-associated increase in hepatic conventional dendritic cells (cDCs) and further defined their source as NASH-induced boost in cycling of cDC progenitors in the bone marrow. Analysis of blood and liver from patients on the NAFLD/NASH spectrum showed that type 1 cDCs (cDC1) were more abundant and activated in disease. Sequencing of physically interacting cDC-T cell pairs from liver-draining lymph nodes revealed that cDCs in NASH promote inflammatory T cell reprogramming, previously associated with NASH worsening. Finally, depletion of cDC1 in XCR1

BackgroundHepatocellular carcinoma (HCC) has a dismal prognosis, and though checkpoint blocking antibodies have significantly improved patient outcome, many patients remain left out, highlighting the need to identify additional immune target to enhance therapeutic immunity. Macrophages (MF) are an abundant and heterogeneous population in the tumor microenvironment (TME), and are associated with a poor prognosis in multiple tumor types, including HCC, however, their molecular and functional diversity is still poorly understood.MethodsWe analyzed the molecular and spatial organization patterns of immune cells within the TME and adjacent tissue of 26 resected HCC lesions using single-cell RNA sequencing and multiplex immunohistochemistry (IHC).ResultsWe found that Kupffer cells, the self-renewing tissue-resident macrophages in liver tissue, are lacking from the TME, which is dominated by monocyte-derived macrophages. ScRNAseq followed by high-resolution clustering identified distinct MF molecular programs within the monocyte-derived macrophage compartment. One MF subset expressed a shared signature with monocytes including FCN1, S100A8 and T cell activation genes like CXCL9 and IL32. Conversely, one subset of MF expressed FOLR2, SEPP1 and genes of the complement (C1Qs), a program shared with KC in the adjacent tissue, and include another intratumoral subset enriched for the expression of TREM2 and GPNMB. Guided by these results, we are developing an IHC antibody panel that allows to visualize distinct MF localization in the TME. Intratumoral MF interface with, and potentially regulate, the T cell compartment within the TME. We are analyzing HCC tumor lesions in our treatment-naïve cohort and in patients treated with neoadjuvant anti-PD-1 therapy (NCT03916627) to study co-localization and direct interaction of MF and T cells using physically-interacting cell sequencing (PICseq). This analysis enables us to identify MF with direct cell-cell contact with T cells, and our preliminary analysis demonstrates an enrichment in MF with an immunosuppressive phenotype. We are also using spatial transcriptomic to map molecular programs of MF in the TME, that we will corroborated with additional patients.ConclusionsTaken together, our data provide a new understanding of intratumoral MF diversity and highlight the presence of specific immunoregulatory MF programs unique to tumor lesions, with subsets of these MF found to be directly interacting with T cells, potentially modulating anti-tumor responsiveness. Our analysis of resected tumor from anti-PD-1 treated patients, will allow us to correlate MF programs, and direct T cell interaction, with clinical response, and will inform therapeutic trials targeting specific MF populations so as to improve clinical efficacy of cancer immunotherapy.Trial RegistrationNCT03916627Ethics ApprovalSamples of tumor and non-involved liver were obtained from surgical specimens of patients undergoing resection at Mount Sinai Hospital (New York, NY) after obtaining informed consent in accordance with a protocol reviewed and approved by the Institutional Review Board at the Icahn School of Medicine at Mount Sinai (RUTH Human Subjects Electronic Submission System 18–00407 and 20–04150) and in collaboration with the Biorepository and Department of Pathology.

Hepatocellular carcinoma (HCC) has a dismal prognosis, and though checkpoint blocking antibodies have significantly improved patient outcome, many patients remain left out highlighting the need to identify additional immune target to enhance therapeutic immunity. Macrophages (MΦ) are an abundant and heterogeneous population in the tumor microenvironment (TME), and are associated with a poor prognosis in multiple tumor types, including HCC, however, their molecular and functional diversity is still poorly understood. We analyzed the molecular and spatial organization patterns of immune cells within the TME and adjacent tissue of 23 resected HCC lesions using single-cell RNA sequencing and multiplex immunohistochemistry (IHC). Strikingly, we found that Kupffer cells (KC), the self-renewing tissue-resident macrophages in liver tissue, are lacking from the TME, which is dominated by monocyte-derived macrophages. ScRNAseq followed by high-resolution clustering identified distinct MΦ molecular programs within the monocyte-derived macrophage compartment. One MΦ subset expressed a shared signature with monocytes including FCN1 and S100A8 in addition to T cell activation genes like CXCL9 and IL32. Conversely, one subset of MΦ expressed FOLR2, SEPP1 and genes of the complement (C1Qs), a program shared with KC in the adjacent uninvolved tissue, and include another intratumoral subset enriched for the expression of TREM2 and GPNMB. Guided by these results, we are developing an IHC antibody panel that allows to visualize distinct MΦ localization in the TME. Intratumoral MΦ interface with, and potentially regulate, the T cell compartment within the TME. We are analyzing HCC tumor lesions in our treatment-naïve cohort and in patients treated with neoadjuvant anti-PD-1 therapy (NCT03916627) to study direct interaction of MΦ and T cells using an innovative technology of physically-interacting cell sequencing (PICseq). This analysis enables us to identify MΦ with direct cell-cell contact with T cells, and our preliminary analysis demonstrates an enrichment in MΦ with a highly immunosuppressive phenotype. We are also using PICseq to map the molecular program of MΦ that are interacting with T cells and that we will corroborated with additional patients. Taken together, our data provide a new understanding of intratumoral MΦ diversity and highlight the presence of specific immunoregulatory MΦ programs unique to tumor lesions, with subsets of these MΦ found to be directly interacting with T cells, potentially modulating anti-tumor responsiveness. Our analysis of resected tumor from anti-PD-1 treated patients, will allow us to correlate MΦ programs, and direct T cell interaction, with clinical response, and will inform therapeutic trials targeting specific MΦ populations so as to improve clinical efficacy of cancer immunotherapy. Citation Format: Pauline Hamon, Assaf Magen, Merav Cohen, Alexandra Tabachnikova, Christie Chang, Mark Buckup, Leanna Troncoso, Zhen Zhao, Joel Kim, Amir Giladi, Nausicaa Malissen, Fiona Desland, Jessica Le Berichel, Ido Amit, Ephraim Kenigsberg, Myron Schwartz, Thomas Marron, Miriam Merad. Characterization of molecular and spatial diversity of macrophages in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 64.

Aims The present study evaluates the effect of antenatal lamotrigine exposure, on short- and long-term paediatric outcome. Methods The study included the children of 83 epileptic women treated with lamotrigine during pregnancy, at a tertiary medical centre between 2004-2014. All newborns were monitored for vital signs, congenital malformations and Finnegan score. In addition, the parents completed a questionnaire regarding their child's development and health up to the age of 12 years. Results No major malformations were found in the newborns. None of the newborns had significant withdrawal symptoms by Finnegan score. The children were followed-up to the age of 12 years (56.6% were 6-12 years at the time of evaluation). There were no significant findings in the incidence of neurodevelopmental disorders. Conclusions According to our experience, lamotrigine is generally safe for pregnancy use, associated with minimal short-term complications with no long-term effects on the outcome.

Background Previous echocardiographic studies have revealed an association between enlarged cardiac chamber volumes and elevated troponin concentrations. An automatic 4-chamber volumetric analysis tool was adopted to investigate this association in patients who underwent cardiac-gated computed tomography angiography (CCTA). Hypothesis We hypothesized that troponin concentration within the normal range correlates with cardiac chambers' volumes. Methods Serum troponin was obtained from 157 ambulatory patients before undergoing CCTA for nonacute coronary artery evaluation. Volumes of the cardiac chambers and the left ventricular mass were automatically analyzed and indexed to body surface area. Patients with a troponin concentrations within the upper quartile (>0.007 ng/mL, n = 39) were compared to patients with a troponin concentrations within the 3 lower quartiles of troponin concentrations (≤0.007 ng/mL, n = 118). Results None of the patients had a troponin concentration >0.05 ng/mL (the 99th percentile of the general population). There were no significant differences in baseline characteristics between the groups. There were significant correlations between troponin and ventricular volumes after adjustments for age and gender. In an analysis that included 107 patients without any known heart diseases, including those pathological findings in the current CCTA, there were significant correlations between troponin and the left and right ventricular volumes after adjustments for age, gender, and baseline characteristics (odds ratio [OR]: 1.08, 95% confidence interval [CI]: 1.03-1.14, P = 0.002 and OR: 1.11, 95% CI: 1.04-1.19, P = 0.002; respectively). Conclusions Using the technology of automatic volumetric analysis in individuals undergoing CCTA, an association between larger right and left cardiac chambers and higher levels of troponin concentration was shown.

Circulating cell-free deoxyribonucleic acid (cfDNA) originates from cells undergoing necrosis and apoptosis or after active secretion and is constantly found in the blood stream. Elevated cfDNA has been reported in pathological conditions, including infections, malignancies and autoimmunity (1-3). We developed a simple fluorescent method to directly measure cfDNA concentrations in biological samples, without prior processing, in clinical laboratories (4).

VENµS is a joint space system venture of Israeli and French governments for Earth observation (EO). The scientific mission focuses on vegetation and land surface monitoring. VENµS was launched on August 1st 2017. It provides 5 and 10 m resolution images in 12 shortwave spectral bands every two days over a set of scientific sites, with constant view angle and overpass time. This article presents the objectives of the mission, its main characteristics and products. It summarizes the scientific programme and the ongoing commissioning phase.

Drug development is currently hampered by the inability of animal experiments to accurately predict human response. While emerging organ on chip technology offers to reduce risk using microfluidic models of human tissues, the technology still mostly relies on end-point assays and biomarker measurements to assess tissue damage resulting in limited mechanistic information and difficulties to detect adverse effects occurring below the threshold of cellular damage. Here we present a sensor-integrated liver on chip array in which oxygen is monitored using two-frequency phase modulation of tissue-embedded microprobes, while glucose, lactate and temperature are measured in real time using microfluidic electrochemical sensors. Our microphysiological platform permits the calculation of dynamic changes in metabolic fluxes around central carbon metabolism, producing a unique metabolic fingerprint of the liver's response to stimuli. Using our platform, we studied the dynamics of human liver response to the epilepsy drug Valproate (Depakine™) and the antiretroviral medication Stavudine (Zerit™). Using E6/E7(LOW) hepatocytes, we show TC(50) of 2.5 and 0.8 mM, respectively, coupled with a significant induction of steatosis in 2D and 3D cultures. Time to onset analysis showed slow progressive damage starting only 15–20 hours post-exposure. However, flux analysis showed a rapid disruption of metabolic homeostasis occurring below the threshold of cellular damage. While Valproate exposure led to a sustained 15% increase in lipogenesis followed by mitochondrial stress, Stavudine exposure showed only a transient increase in lipogenesis suggesting disruption of β-oxidation. Our data demonstrates the importance of tracking metabolic stress as a predictor of clinical outcome.

Microfluidic sorting offers a unique ability to isolate large numbers of cells for bulk proteomic or metabolomics studies but is currently limited by low throughput and persistent clogging at low flow rates. Recently we uncovered the physical principles governing the inertial focusing of particles in high-Reynolds numbers. Here, we superimpose high Reynolds inertial focusing on Dean vortices, to rapidly isolate large quantities of young and adult yeast from mixed populations at a rate of 107 cells/min/channel. Using a new algorithm to rapidly quantify budding scars in isolated yeast populations and system-wide proteomic analysis, we demonstrate that protein quality control and expression of established yeast aging markers such as CalM, RPL5, and SAM1 may change after the very first replication events, rather than later in the aging process as previously thought. Our technique enables the large-scale isolation of microorganisms based on minute differences in size (±1.5 μm), a feat unmatched by other technologies.

Summary The influenza virus is a major cause of morbidity and mortality worldwide. Yet, both the impact of intracellular viral replication and the variation in host response across different cell types remain uncharacterized. Here we used single-cell RNA sequencing to investigate the heterogeneity in the response of lung tissue cells to in vivo influenza infection. Analysis of viral and host transcriptomes in the same single cell enabled us to resolve the cellular heterogeneity of bystander (exposed but uninfected) as compared with infected cells. We reveal that all major immune and non-immune cell types manifest substantial fractions of infected cells, albeit at low viral transcriptome loads relative to epithelial cells. We show that all cell types respond primarily with a robust generic transcriptional response, and we demonstrate novel markers specific for influenza-infected as opposed to bystander cells. These findings open new avenues for targeted therapy aimed exclusively at infected cells., Graphical Abstract, Highlights • Combined measurements of host-viral scRNA-seq during in vivo influenza infection • High prevalence of infection in a variety of immune and non-immune cell types • Extensive cellular heterogeneity exists within infected and bystander cells • Generic and cell-type-specific differences between infected and bystander cells, Simultaneous mapping of host and viral transcriptomes at the same single cell provides a framework to study host-viral interactions. Analysis of cells derived from lungs of in vivo influenza infection reveals both generic and cell-type-specific infection response. By analyzing the cellular heterogeneity of both bystander (exposed but uninfected) and infected cells, we characterize novel markers specific for influenza-infected as opposed to bystanders. These findings open new avenues for targeted therapy aimed exclusively at infected cells.

Prediction of drug-induced toxicity is complicated by the failure of animal models to extrapolate human response, especially during assessment of repeated dose toxicity for cosmetic or chronic drug treatments. In this work, we present a 3D microreactor capable of maintaining metabolically active HepG2/C3A spheroids for over 28 days in vitro under stable oxygen gradients mimicking the in vivo microenvironment. Mitochondrial respiration was monitored using two-frequency phase modulation of phosphorescent microprobes embedded in the tissue. Phase modulation is focus independent and unaffected by cell death or migration. This sensitive measurement of oxygen dynamics revealed important information on the drug mechanism of action and transient subthreshold effects. Specifically, exposure to antiarrhythmic agent, amiodarone, showed that both respiration and the time to onset of mitochondrial damage were dose dependent showing a TC50 of 425 μm. Analysis showed significant induction of both phospholipidosis and microvesicular steatosis during long-term exposure. Importantly, exposure to widely used analgesic, acetaminophen, caused an immediate, reversible, dose-dependent loss of oxygen uptake followed by a slow, irreversible, dose-independent death, with a TC50 of 12.3 mM. Transient loss of mitochondrial respiration was also detected below the threshold of acetaminophen toxicity. The phenomenon was repeated in HeLa cells that lack CYP2E1 and 3A4, and was blocked by preincubation with ascorbate and TMPD. These results mark the importance of tracing toxicity effects over time, suggesting a NAPQI-independent targeting of mitochondrial complex III might be responsible for acetaminophen toxicity in extrahepatic tissues.

The liver is the main organ responsible for the modification, clearance, and transformational toxicity of most xenobiotics owing to its abundance in cytochrome P450 (CYP450) enzymes. However, the scarcity and variability of primary hepatocytes currently limits their utility. Human pluripotent stem cells (hPSCs) represent an excellent source of differentiated hepatocytes; however, current protocols still produce fetal-like hepatocytes with limited mature function. Interestingly, fetal hepatocytes acquire mature CYP450 expression only postpartum, suggesting that nutritional cues may drive hepatic maturation. We show that vitamin K2 and lithocholic acid, a by-product of intestinal flora, activate pregnane X receptor (PXR) and subsequent CYP3A4 and CYP2C9 expression in hPSC-derived and isolated fetal hepatocytes. Differentiated cells produce albumin and apolipoprotein B100 at levels equivalent to primary human hepatocytes, while demonstrating an 8-fold induction of CYP450 activity in response to aryl hydrocarbon receptor (AhR) agonist omeprazole and a 10-fold induction in response to PXR agonist rifampicin. Flow cytometry showed that over 83% of cells were albumin and hepatocyte nuclear factor 4 alpha (HNF4α) positive, permitting high-content screening in a 96-well plate format. Analysis of 12 compounds showed an R2 correlation of 0.94 between TC50 values obtained in stem cell–derived hepatocytes and primary cells, compared to 0.62 for HepG2 cells. Finally, stem cell–derived hepatocytes demonstrate all toxicological endpoints examined, including steatosis, apoptosis, and cholestasis, when exposed to nine known hepatotoxins. Conclusion: Our work provides fresh insights into liver development, suggesting that microbial-derived cues may drive the maturation of CYP450 enzymes postpartum. Addition of these cues results in the first functional, inducible, hPSC-derived hepatocyte for predictive toxicology. (Hepatology 2015;62:265-278)

The facilitative glucose transporter (GLUT) family plays a key role in metabolic homeostasis, controlling the absorption rates and rapid response to changing carbohydrate levels. The facilitative GLUT2 transporter is uniquely expressed in metabolic epithelial cells of the intestine, pancreas, liver, and kidney. GLUT2 dysfunction is associated with several pathologies, including Fanconi-Bickel syndrome, a glycogen storage disease, characterized by growth retardation and renal dysfunction. Interestingly, GLUT2 activity is modulated by its cellular localization. Membrane translocation specifically regulates GLUT2 activity in enterocytes, pancreatic β-cells, hepatocytes, and proximal tubule cells. We have established a system to visualize and quantify GLUT2 translocation, and its dynamics, by live imaging of a mCherry-hGLUT2 fusion protein in polarized epithelial cells. This system enables testing of putative modulators of GLUT2 translocation, which are potential drugs for conditions of impaired glucose homeostasis and associated nephropathy.

The facilitative glucose transporter (GLUT) family plays a key role in metabolic homeostasis, controlling the absorption rates and rapid response to changing carbohydrate levels. The facilitative GLUT2 transporter is uniquely expressed in metabolic epithelial cells of the intestine, pancreas, liver, and kidney. GLUT2 dysfunction is associated with several pathologies, including Fanconi-Bickel syndrome, a glycogen storage disease, characterized by growth retardation and renal dysfunction. Interestingly, GLUT2 activity is modulated by its cellular localization. Membrane translocation specifically regulates GLUT2 activity in enterocytes, pancreatic β-cells, hepatocytes, and proximal tubule cells. We have established a system to visualize and quantify GLUT2 translocation, and its dynamics, by live imaging of a mCherry-hGLUT2 fusion protein in polarized epithelial cells. This system enables testing of putative modulators of GLUT2 translocation, which are potential drugs for conditions of impaired glucose homeostasis and associated nephropathy.

BACKGROUND: Previous echocardiographic studies have revealed an association between enlarged cardiac chamber volumes and elevated troponin concentrations. An automatic 4‐chamber volumetric analysis tool was adopted to investigate this association in patients who underwent cardiac‐gated computed tomography angiography (CCTA). HYPOTHESIS: We hypothesized that troponin concentration within the normal range correlates with cardiac chambers' volumes. METHODS: Serum troponin was obtained from 157 ambulatory patients before undergoing CCTA for nonacute coronary artery evaluation. Volumes of the cardiac chambers and the left ventricular mass were automatically analyzed and indexed to body surface area. Patients with a troponin concentrations within the upper quartile (>0.007 ng/mL, n = 39) were compared to patients with a troponin concentrations within the 3 lower quartiles of troponin concentrations (≤0.007 ng/mL, n = 118). RESULTS: None of the patients had a troponin concentration >0.05 ng/mL (the 99th percentile of the general population). There were no significant differences in baseline characteristics between the groups. There were significant correlations between troponin and ventricular volumes after adjustments for age and gender. In an analysis that included 107 patients without any known heart diseases, including those pathological findings in the current CCTA, there were significant correlations between troponin and the left and right ventricular volumes after adjustments for age, gender, and baseline characteristics (odds ratio [OR]: 1.08, 95% confidence interval [CI]: 1.03‐1.14, P = 0.002 and OR: 1.11, 95% CI: 1.04‐1.19, P = 0.002; respectively). CONCLUSIONS: Using the technology of automatic volumetric analysis in individuals undergoing CCTA, an association between larger right and left cardiac chambers and higher levels of troponin concentration was shown.

The central nervous system (CNS) is endowed with several immune-related mechanisms that contribute to its protection and maintenance in homeostasis and under pathology. Here, we discovered an additional mechanism that controls inflammatory responses within the CNS milieu under injurious conditions, involving CD200 ligand (CD200L) expressed by newly formed endothelial cells. We observed that CD200L is constitutively expressed in the mouse healthy CNS by endothelial cells of the blood–cerebrospinal fluid barrier and of the spinal cord meninges, but not by the endothelium of the blood–spinal cord barrier. Following spinal cord injury (SCI), newly formed endothelial cells, located only at the epicenter of the lesion site, expressed CD200L. Moreover, in the absence of CD200L expression by CNS-resident cells, functional recovery of mice following SCI was impaired. High throughput single-cell flow cytometry image analysis following SCI revealed CD200L-dependent direct interaction between endothelial and local CD200R+myeloid cells, including activated microglia and infiltrating monocyte-derived macrophages (mo-MΦ). Absence of CD200L signaling, bothin vitroandin vivo, resulted in a higher inflammatory response of the encountering macrophages, manifested by elevation in mRNA expression ofTnfα andIl1β, increased intracellular TNFα immunoreactivity, and reduced expression levels of macrophage factors that are associated with resolution of inflammation, Dectin-1, CD206 (mannose receptor), and IL-4R. Collectively, our results highlight the importance of CD200-mediated immune dialogue between endothelial cells and the local resident microglia and infiltrating mo-MΦ within the lesion area, as a mechanism that contributes to regulation of inflammation following acute CNS injury.SIGNIFICANCE STATEMENTThis manuscript focuses on a novel mechanism of inflammation-regulation following spinal cord injury (SCI), orchestrated by CD200-ligand (CD200L) expressed by newly formed endothelial cells within the lesion site. Our study reveals that, in homeostasis, CD200L is expressed by endothelial cells of the mouse blood–cerebrospinal fluid barrier and of the blood–leptomeningeal barrier, but not by endothelial cells of the blood–spinal cord barrier. Following SCI, newly formed endothelial cells located within the epicenter of the lesion site were found to express CD200L at time points that were shown to be critical for repair. Our results reveal a direct interaction between CD200L+endothelial cells and CD200R+microglia and macrophages, resulting in attenuated inflammation, biasing macrophage phenotype toward inflammation-resolving cells, and promotion of functional recovery following SCI.

Altered glucose reabsorptionviathe facilitative glucose transporter 2 (GLUT2) during diabetes may lead to renal proximal tubule cell (RPTC) injury, inflammation, and interstitial fibrosis. These pathologies are also triggered by activating the cannabinoid-1 receptor (CB1R), which contributes to the development of diabetic nephropathy (DN). However, the link between CB1R and GLUT2 remains to be determined. Here, we show that chronic peripheral CB1R blockade or genetically inactivating CB1Rs in the RPTCs ameliorated diabetes-induced renal structural and functional changes, kidney inflammation, and tubulointerstitial fibrosis in mice. Inhibition of CB1R also downregulated GLUT2 expression, affected the dynamic translocation of GLUT2 to the brush border membrane of RPTCs, and reduced glucose reabsorption. Thus, targeting peripheral CB1R or inhibiting GLUT2 dynamics in RPTCs has the potential to treat and ameliorate DN. These findings may support the rationale for the clinical testing of peripherally restricted CB1R antagonists or the development of novel renal-specific GLUT2 inhibitors against DN.

Monocyte-derived macrophages (mo-MΦs) and T cells have been shown to contribute to spinal cord repair. Recently, the remote brain choroid plexus epithelium (CP) was identified as a portal for monocyte recruitment, and its activation for leukocyte trafficking was found to be IFN-γ-dependent. Here, we addressed how the need for effector T cells can be reconciled with the role of inflammation-resolving immune cells in the repair process. Using an acute spinal cord injury model, we show that in mice deficient in IFN-γ-producing T cells, the CP was not activated, and recruitment of inflammation-resolving mo-MΦ to the spinal cord parenchyma was limited. We further demonstrate that mo-MΦ locally regulated recruitment of thymic-derived Foxp3(+) regulatory T (Treg) cells to the injured spinal cord parenchyma at the subacute/chronic phase. Importantly, an ablation protocol that resulted in reduced Tregs at this stage interfered with tissue remodeling, in contrast to Treg transient ablation, restricted to the 4 d period before the injury, which favored repair. The enhanced functional recovery observed following such a controlled decrease of Tregs suggests that reduced systemic immunosuppression at the time of the insult can enhance CNS repair. Overall, our data highlight a dynamic immune cell network needed for repair, acting in discrete compartments and stages, and involving effector and regulatory T cells, interconnected by mo-MΦ. Any of these populations may be detrimental to the repair process if their level or activity become dysregulated. Accordingly, therapeutic interventions must be both temporally and spatially controlled.

Scorpion sting may cause myocardial injury and heart failure (HF). Clinical signs of failure may develop several hours or even days after the sting, while electrocardiography (ECG) and blood examination soon after the sting may be normal. We sought to examine whether normal echocardiographic (echo) examination performed shortly after hospital arrival would exclude subsequent HF. We also sought to check if blood troponin and natriuretic peptide values measured shortly after arrival may predict or exclude subsequent HF. Natriuretic peptide activities have not been measured in scorpion sting victims. We also wanted to check if HF occurs in envenomated young infants. In a 3-year prospective study we looked at the demographic, clinical, laboratory, ECG, and echo data of all patients with general envenomation who arrived at the emergency department (ED) after scorpion sting. Clinical, laboratory, ECG, and echo results on arrival and 24 h after arrival were checked and compared between groups of patients with normal and abnormal echo on arrival. We then looked for differences in clinical course, therapy, and outcome between groups. The study included 98 children aged 80 days to 19 years (median 53.1 months), 25 were below the age of 2 years. Envenomation by the "yellow scorpion"Leiurus quinquestriatus was suspected in 74 cases. Median time between sting and ED arrival was 80 min. Echo was performed on arrival in 93 of the 98 patients, (in 5 occasions it was not performed or not recorded) 74 were normal and 19 were abnormal. Abnormal echo included hypokinesia and low fractional shortening and ejection fraction of the left ventricle. Clinical signs, abnormal ECG, and laboratory results were not discriminative between groups on arrival. Mean troponin T was higher in patients with abnormal echo, but within normal range in 13 of the 19 patients with abnormal echo and above normal in 2 of the 74 patients with normal echo-missing sensitivity and specificity. Mean N-terminal pro B-type natriuretic peptide was above normal in both groups but within normal range in 5 patients with abnormal echo and above normal range in 24 patients with normal echo-missing sensitivity and specificity. None of the patients with normal echo had subsequent HF and none of the children younger than 2 years of age had HF. All patients survived the intoxication and were discharged home without sequel. We conclude that early echo examination is an important procedure. In our study, normal examination excluded subsequent HF. Abnormal examination accelerated cardiac therapy which might have contributed to our favorable outcome. HF did not occur in infants younger than two years of age.

OBJECTIVE The positive correlation between the time from symptom onset to the appearance of an inflammatory response and erythrocyte aggregation (EA) in the peripheral blood of acute coronary syndromes (ACS) patients had been previously reported by us. We now analyze the added prognostic value of EA in ACS patients undergoing percutaneous coronary interventions (PCI). METHODS We performed an analysis on prospectively collected data at a tertiary hospital catheterization laboratory between 2006-2011. Cox regression models were fitted for EA cut-offs and performed separately for myocardial infarction (MI) and unstable angina pectoris (UAP) patients. Major adverse cardiovascular events (MACE) were defined as all-cause mortality, MI and stroke. Follow up time was defined as the time from PCI to either MACE or November 20, 2011. RESULTS Included were 1055 patients (637 with MI and 418 with UAP). The median follow up in the MI and the UAP groups was 14 and 15 months, respectively (maximal follow up of 4.1 years). In the UAP group there was a significant increase in the MACE for the group with high EA (HR = 2.3, p = 0.04) compared to the group of patients with low EA. This was not found for patients presenting with MI. CONCLUSIONS Elevated EA portends worse outcomes in UAP patients undergoing PCI.

Microfluidic organ-on-a-chip technology aims to replace animal toxicity testing, but thus far has demonstrated few advantages over traditional methods. Mitochondrial dysfunction plays a critical role in the development of chemical and pharmaceutical toxicity, as well as pluripotency and disease processes. However, current methods to evaluate mitochondrial activity still rely on end-point assays, resulting in limited kinetic and prognostic information. Here, we present a liver-on-chip device capable of maintaining human tissue for over a month in vitro under physiological conditions. Mitochondrial respiration was monitored in real time using two-frequency phase modulation of tissue-embedded phosphorescent microprobes. A computer-controlled microfluidic switchboard allowed contiguous electrochemical measurements of glucose and lactate, providing real-time analysis of minute shifts from oxidative phosphorylation to anaerobic glycolysis, an early indication of mitochondrial stress. We quantify the dynamics of cellular adaptation to mitochondrial damage and the resulting redistribution of ATP production during rotenone-induced mitochondrial dysfunction and troglitazone (Rezulin)-induced mitochondrial stress. We show troglitazone shifts metabolic fluxes at concentrations previously regarded as safe, suggesting a mechanism for its observed idiosyncratic effect. Our microfluidic platform reveals the dynamics and strategies of cellular adaptation to mitochondrial damage, a unique advantage of organ-on-chip technology.

There is increasing evidence localizes the mitochondrial chaperone heat shock protein (HSP)60, outside the cell, where it mediates interactions between immune cells and other body tissues. However, the mechanisms by which HSP60 is secreted into the extracellular environment are not fully understood. Recent studies have shown that HSP60 is actively released by a nonconventional secretion mechanism, the lipid raft–exosome pathway. In the present study, we show for the first time that HSP60, produced by 3-methylcholantrene-induced fibrosarcoma tumour cells, is secreted through the conventional endoplasmic reticulum–Golgi secretory pathway. Confocal microscopy using anti-TGN38 and anti-HSP60 antibodies together with monensin, a Golgi transport inhibitor, demonstrated the relocation of HSP60 to the Golgi of malignant cells but not primary fibroblast cells subjected to heat shock or fibroblast cell lines. Transmission electron microscopy, flow cytometry and cell fractionation of cell treated with brefeldin A, an inhibitor of endoplasmic reticulum to Golgi protein transport, further indicated that HSP60 is present both in the endoplasmic reticulum and the Golgi complex of malignant cells. We found a single mRNA with a mitochondrial targeting sequence encoding for HSP60 in the malignant cells but two HSP60 translation products, namely the native unmodified protein and a protein post-translationally modified by N-glycosylation. The N-glycans observed were composed of high-mannose structures and bi-, tri- and tetra-antennary complex type structures occupying sites of the three potential glycosylation sites present on HSP60. Accordingly, we propose that HSP60 in malignant cells is transported through the endoplasmic reticulum–Golgi secretion pathway, where it acquires N-glycans, and thus can affect the immunological properties of the proteins in the tumour microenvironment. Structured digital abstract • Grp94 and Hsp60 colocalize by cosedimentation through density gradient (View interaction)

Sialylation of tumor cells is involved in various aspects of their malignancy (proliferation, motility, invasion, and metastasis); however, its effect on the process of immunoediting that affects tumor cell immunogenicity has not been studied. We have shown that in mice with impaired immunoediting, such as in IL-1α−/− and IFNγ−/− mice, 3-methylcholanthrene–induced fibrosarcoma cells are immunogenic and concomitantly bear low levels of surface sialylation, whereas tumor cells derived from wild type mice are nonimmunogenic and bear higher levels of surface sialylation. To study immune mechanisms whose interaction with tumor cells involves surface sialic acid residues, we used highly sialylated 3-methylcholanthrene–induced nonimmunogenic fibrosarcoma cell lines from wild type mice, which were treated with sialidase to mimic immunogenic tumor cell variants. In vivo and in vitro experiments revealed that desialylation of tumor cells reduced their growth and induced cytotoxicity by NK cells. Moreover, sialidase-treated tumor cells better activated NK cells for IFN-γ secretion. The NKG2D-activating receptor on NK cells was shown to be involved in interactions with desialylated ligands on tumor cells, the nature of which is still not known. Thus, the degree of sialylation on tumor cells, which is selected during the process of immunoediting, has possibly evolved as an important mechanism of tumor cells with low intrinsic immunogenicity or select for tumor cells that can evade the immune system or subvert its function. When immunoediting is impaired, such as in IFN-γ−/− and IL-1α−/− mice, the overt tumor consists of desialylayed tumor cells that interact better with immunosurveillance cells.

SummaryAnimals modify food-seeking behavior and metabolism according to perceived food availability. Here we show that, in the roundworm C. elegans, release of neuropeptides from interneurons that are directly postsynaptic to olfactory, gustatory, and thermosensory neurons coordinately regulates behavior and metabolism. Animals lacking these neuropeptides, encoded by the flp-18 gene, are defective in chemosensation and foraging, accumulate excess fat, and exhibit reduced oxygen consumption. Two G protein-coupled receptors of the NPY/RFamide family, NPR-4 and NPR-5, are activated by FLP-18 peptides in vitro and exhibit mutant phenotypes that recapitulate those of flp-18 mutants. Our data suggest that sensory input can coordinately regulate behavior and metabolism via NPY/RFamide-like receptors. They suggest that peptidergic feedback from interneurons regulates sensory neuron activity, and that at least some of this communication occurs extrasynaptically. Extrasynaptic neuropeptide signaling may greatly increase the computational capacity of neural circuits.

In a previous study we demonstrated a down-regulatory effect of vitamin D active metabolite (1,25(OH)(2)D(3)) and its vitamin D(2) analog (1,24(OH)(2)D(2)) on TNFalpha expression in macrophages. We also found an inhibitory effect in the physiological concentration (10(-10)M) of 1,25(OH)(2)D(3) which was dose-dependent. This down-regulation, caused by the decrease in NFkappaB activity by 1,25(OH)(2)D(3) and 1,24(OH)(2)D(2), was demonstrated in P388D1 cells transfected with NFkappaB reporter gene (p NFkappaB-Luc) and by EMSA. In our present study we investigated the processes leading to reduced NFkappaB activity on P388D1 cells. A decrease in nuclei NFkappaB-p65 and an increase in cytosolic NFkappaB-p65, were measured, while no changes in total NFkappaB-p65 mRNA and protein levels were observed. Simultaneously, a significant increase in both mRNA and protein levels of the NFkappaB-cytosolic inhibitor, IkappaBalpha, were determined. The half-life of IkappaBalpha-mRNA increased, with a parallel decrease in the phosphorylation of its protein, as the first step of ubiquitinization and degradation. The present results demonstrate that 1,25(OH)(2)D(3) and 1,24(OH)(2)D(2) inhibit TNFalpha expression in macrophages, by increasing IkappaBalpha and decreasing NFkappaB activity. Since NFkappaB is a major transcription factor for TNFalpha and other inflammatory mediators, these findings suggest that 1,25(OH)(2)D(3) and 1,24(OH)(2)D(2) may be used therapeutically as anti-inflammatory agents.

The liver is the largest internal organ in mammals, serving a wide spectrum of vital functions. Loss of liver function due to drug toxicity, progressive fatty liver disease, or viral infection is a major cause of death in the United States of America. Pharmaceutical and cosmetic toxicity screening, basic research and the development of bioartificial liver devices require long-term hepatocyte culture techniques that sustain hepatocyte morphology and function. In recent years, several techniques have been developed that can support high levels of liver-specific gene expression, metabolic function, and synthetic activity for several weeks in culture. These include the collagen double gel configuration, hepatocyte spheroids, coculture with nonparenchymal cells, and micropatterned cocultures. This chapter will cover the current status of hepatocyte culture techniques, including media formulation, oxygen supply, and heterotypic cell-cell interactions.

Item does not contain fulltext Hepatocytes have a critical role in metabolism, but their study is limited by the inability to expand primary hepatocytes in vitro while maintaining proliferative capacity and metabolic function. Here we describe the oncostatin M (OSM)-dependent expansion of primary human hepatocytes by low expression of the human papilloma virus (HPV) genes E6 and E7 coupled with inhibition of epithelial-to-mesenchymal transition. We show that E6 and E7 expression upregulates the OSM receptor gp130 and that OSM stimulation induces hepatocytes to expand for up to 40 population doublings, producing 1013 to 1016 cells from a single human hepatocyte isolate. OSM removal induces differentiation into metabolically functional, polarized hepatocytes with functional bile canaliculi. Differentiated hepatocytes show transcriptional and toxicity profiles and cytochrome P450 induction similar to those of primary human hepatocytes. Replication and infectivity of hepatitis C virus (HCV) in differentiated hepatocytes are similar to those of Huh7.5.1 human hepatoma cells. These results offer a means of expanding human hepatocytes of different genetic backgrounds for research, clinical applications and pharmaceutical development.

Background In a previous study we demonstrated the inhibitory effect of 1,25-dihydroxyvitamin D (1,25(OH)(2)D(3)) and its less calcaemic analog 1,24(OH)(2)D(2) on the production of tumour necrosis factor alpha (TNFalpha) by human peritoneal macrophages. The aim of the present study is to examine whether this vitamin D inhibition of TNFalpha is mediated by its major transcription factor, nuclear factor-kappaB (NFkappaB). Methods Murine macrophage cells (P388D1) were incubated with 10(-7) M 1,25(OH)(2)D(3) or 1,24(OH)(2)D(2) and then stimulated with lipopolysaccharide. NFkappaB activity was assayed using a reporter gene and by electrophoretic mobility shift assay (EMSA). In addition, we evaluated mRNA and protein levels of NFkappaB-p65 and of IkappaBalpha, a potent NFkappaB inhibitor, and phosphorylated IkappaBalpha. Results Both 1,25(OH)(2)D(3) and 1,24(OH)(2)D(2) induced a 60% reduction of TNFalpha secretion. By using a reporter gene and EMSA we found that vitamin D markedly reduced NFkappaB activity. 1,25(OH)(2)D(3) or 1,24(OH)(2)D(2) decreased NFkappaB-p65 levels in the nucleus and increased NFkappaB-p65 levels in the cytosol; no changes were observed in the total levels of NFkappaB-p65 protein and mRNA. Concurrently, vitamin D induced a significant increase in mRNA and protein levels of IkappaBalpha (approximately 6.5- and 4.5-fold, respectively). Elevated levels of IkappaBalpha can be explained by the vitamin D-induced prolongation of IkappaBalpha-mRNA half-life from 110 to 190 min and by the decrease in IkappaBalpha phosphorylation. Conclusions Vitamin D up-regulates IkappaBalpha levels by increasing mRNA stability and decreasing IkappaBalpha phosphorylation. The increase in IkappaBalpha levels reduces nuclear translocation of NFkappaB and thereby downgrades its activity. Since NFkappaB is a major transcription factor of inflammatory mediators, these findings suggest that the less-calcaemic analog, 1,24(OH)(2)D(2) may be effective as an anti-inflammatory therapeutic agent.

Prostate cancer is the most commonly diagnosed type of cancer in men, and there is no available cure for patients with advanced disease. In vitro model systems are urgently required to permit the study of human prostate cell differentiation and malignant transformation. Unfortunately, human prostate cells are particularly difficult to convert into continuously growing cultures. We report here the successful immortalization without viral oncogenes of prostate epithelial cells and, for the first time, prostate stromal cells. These cells exhibit a significant pattern of authentic prostate-specific features. In particular, the epithelial cell culture is able to differentiate into glandular buds that closely resemble the structures formed by primary prostate epithelial cells. The stromal cells have typical characteristics of prostate smooth muscle cells. These immortalized cultures may serve as a unique experimental platform to permit several research directions, including the study of cell-cell interactions in an authentic prostate microenvironment, prostate cell differentiation, and most significantly, the complex multistep process leading to prostate cell transformation. (Cancer Res 2006; 66(7): 3531-40)

We introduce a quasi 3-D thermal evolution model for a spherical comet nucleus, which takes into account the diurnal and latitudinal variation of the solar flux, but neglects lateral heat conduction, which is shown to be insignificant. Comparing this model with the ‘fast-rotator’, evenly heated nucleus model, we show that, for long-term calculations of the evolution of the interior, the latter provides a good approximation. The 3-D model is applied to comet 46P/Wirtanen : yielding the distribution of temperature and water production rate over the nucleus surface. A very good agreement with observations is obtained for the integrated production rate. The model is also used in order to derive the change of shape due to uneven erosion. Two cases are considered for different inclination angles of the spin axis; it is concluded that the evolved shape depends strongly on the obliquity of the comet’s spin axis.

The Kuiper Belt zone is unique insofar as the major heat sources of objects a few tens of kilometers in size—solar radiation on the one hand and radioactive decay on the other—have comparable power. This leads to unique evolutionary patterns, with heat waves propagating inward from the irradiated surface and outward from the radioactively heated interior. A major radioactive source that is considered in this study is 26 Al. The long-term evolution of several models with characteristics typical of Kuiper Belt objects is followed by means of a 1-D numerical code that solves the heat and mass balance equations on a spherically symmetric grid. The free parameters considered are radius (10–500 km), heliocentric distance (30–120 AU), and initial 26 Al content (0–5×10 −8 by mass). The initial composition assumed is a porous mixture of ices (H 2 O, CO, and CO 2 ) and dust. Gases released in the interior are allowed to escape to the surface. It is shown that, depending on parameters, the interior may reach quite high temperatures (up to 180 K). The models suggest that Kuiper Belt objects are likely to lose the ices of very volatile species during early evolution; ices of less volatile species are retained in a surface layer, about 1 km thick. The models indicate that the amorphous ice crystallizes in the interior, and hence some objects may also lose part of the volatiles trapped in amorphous ice. Generally, the outer layers are far less affected than the inner part, resulting in a stratified composition and altered porosity distribution. These changes in structure and composition should have significant consequences for the short-period comets, which are believed to be descendants of Kuiper Belt objects.