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Background: Deregulation of microRNAs (miRNAs)has been associated with various human pathologies including bacterial infections.Aim: To investigate the role of miRNAs as blood biomarkers for the diagnosis of active pulmonary tuberculosis (TB).Materials and methods: We studied 50 patients, classified into 3 groups:(i) 17individuals with latent tuberculosis infection (LTBI) (ii) 17 active pulmonary TB patients (iii) 16 healthy individuals. Blood was collected in a PAXgene Blood RNA tubefor thelater isolation oftotal RNA. MiRNA quantification was performed with SurePrint G3 8x60K miRNA microarrays (Agilent). Real time-quantitative polymerase chain reaction (RT-qPCR)with the miScript PCR System (Qiagen) was used to validateselectedmiRNAexpression levels.Results: MiRNA expression patternswere comparedin whole blood from active TBpatients, LTBI individuals and healthy controls. Aset of miRNAs differentially deregulated during active pulmonary TB vs.LTBI and healthy controlswas identified. We then selected nine miRNAsfor validation in a larger patient cohort. The set of miRNAs consisting of miR-150, miR-21, miR-29cand miR-194 enabled to rapidly diagnose pulmonary TB with 91.21% sensitivity and 87.95% specificity.Conclusions:Theidentified novel miRNA signature opens the possibility of developinga simple, rapid and cheap TB diagnostic test from blood This work was supported by agrant from the Spanish Ministerio de Ciencia e Innovación SAF2010–21336. Andreas Meyerhans is a researcher founded from the Institucio Catalana de Recerca i Estudis Avancats (ICREA). Irene Latorre wasthe recipient of a joint ERS/SEPAR Long-Term fellowship (LTRF 82-2012)during this work

A coordinated action of innate and adaptive immune responses is required to efficiently combat a microbial infection. It has now become clear that cancer therapies also largely benefit when both arms of the immune response are engaged. In this review, we will briefly describe the current knowledge of innate immunity and how this can be utilized to prime tumors for a better response to immune checkpoint inhibitors. Comments on compounds in development and ongoing clinical trials will be provided. AM is supported by a grant from the Spanish Ministry of Economy, Industry and Compet-itiveness and FEDER grant no. SAF2016-75505-R (AEI/MINEICO/FEDER, UE), and the ‘María de Maeztu’ Programme for Units of Excellence in R&D (MDM-2014-0370). Work in Dr Rosell’s laboratory is partially supported by a grant from La Caixa Foundation, and by a European Grant (ELBA no 765492).

Molecules that block virus entry by interfering with the actions of viral fusion proteins are of primary concern in the search for antiviral drugs. [...]

Soraphen A is a myxobacterial metabolite that blocks the acetyl-coenzyme A carboxylase of the host and was previously identified as a novel HIV inhibitor. Here, we report that soraphen A acts by reducing virus production and altering the gp120 virion content, impacting entry capacity and infectivity. These effects are partially reversed by addition of palmitic acid, suggesting that inhibition of HIV envelope palmitoylation is one of the mechanisms of antiviral action. The research was funded by the German Centre for Infection Research (DZIF), Spanish Ministry of Economy, Industry and Competitiveness and FEDER BES-2011-048569, Spanish Ministry of Economy, Industry and Competitiveness and FEDER SAF2013-46077-R SAF2016-75505-R, the Spanish Ministry of Economy, Industry and Competitiveness and FEDER BFU2016-80039-R and the Maria de Maetzu Programme for Units of Excellence in R&DMDM-2014-0370

A hepatitis C virus (HCV) epidemic affecting HIV-infected men who have sex with men (MSM) is expanding worldwide. In spite of the improved cure rates obtained with the new direct-acting antiviral drug (DAA) combinations, the high rate of reinfection within this population calls urgently for novel preventive interventions. In this study, we determined in cell culture and ex vivo experiments with human colorectal tissue that lipoquads, G-quadruplex DNA structures fused to cholesterol, are efficient HCV pangenotypic entry and cell-to-cell transmission inhibitors. Thus, lipoquads may be promising candidates for the development of rectally applied gels to prevent HCV transmission., We thank Paul Ziprin and the Department of Surgery and Cancer at St. Mary’s Hospital, Imperial College London, for their assistance in obtaining human tissue. We do not have anything to disclose regarding funding or conflicts of interest with respect to the manuscript. We are supported by grants BFU2013-44629-R (to J.D., G.K., G.P.- V., and A.P.D.L.) and BFU2016-80039-R (to J.D. and G.P.-V.) and also through the María de Maeztu Programme for Units of Excellence in R&D (MDM-2014-0370), all from the Spanish Ministry of Economy, Industry and Competitiveness and FEDER. Work at Imperial College London (C.H.) was funded by EC FP7 grant 305578 (PathCO).

Die vierte industrielle Revolution wird künftig die Arbeitswelt prägen und verändern. Herkömmliche Arbeitsstrukturen werden durch die Verschmelzung virtueller und realer Prozesse und fortschrittliche Kommunikationsstrukturen auf die Probe gestellt. Für die Praxis ergeben sich daraus zahlreiche Fragen zu Arbeitszeit, Betriebsstrukturen und Datenschutz. Einen Leitfaden für die tatsächlichen und rechtlichen Herausforderungen der künftigen Arbeitswelt bieten Ihnen die erfahrenen Anwältinnen und Anwälte der internationalen Wirtschaftskanzlei Baker McKenzie, die sich intensiv mit der "Arbeitswelt 4.0" in der betrieblichen Praxis befasst haben.

Appendix. Numerical method; numerical implementation; values of parameters [43]. (PDF 38 kb)

International audience; Human Immunodeficiency Virus (HIV) infection of humans represents a complex biological system and a great challenge to public health. Novel approaches for the analysis and prediction of the infection dynamics based on a multi-scale integration of virus ontogeny and immune reactions are needed to deal with the systems' complexity. The aim of our study is: (1) to formulate a multi-scale mathematical model of HIV infection; (2) to implement the model computationally following a hybrid approach; and (3) to calibrate the model by estimating the parameter values enabling one to reproduce the " standard " observed dynamics of HIV infection in blood during the acute phase of primary infection. The modeling approach integrates the processes of infection spread and immune responses in Lymph Nodes (LN) to that observed in blood. The spatio-temporal population dynamics of T lymphocytes in LN in response to HIV infection is governed by equations linking an intracellular regulation of the lymphocyte fate by intercellular cytokine fields. We describe the balance of proliferation, differentiation and death at a single cell level as a consequence of gene activation via multiple signaling pathways activated by IL-2, IFNa and FasL. Distinct activation thresholds are used in the model to relate different modes of cellular responses to the hierarchy of the relative levels of the cytokines. We specify a reference set of model parameter values for the fundamental processes in lymph nodes that ensures a reasonable agreement with viral load and CD4 + T cell dynamics in blood.

2501 Background: Durvalumab (MEDI4736), a programmed cell death-ligand 1 (PD-L1) blocking antibody, is currently approved for treatment of several cancer types. As HIV-1-infected (HIV+) patients have been excluded from cancer clinical trials, there are no data on the safety of durvalumab in this population. Methods: DURVAST (NCT03094286) is a multicenter, open-label, phase 2 clinical trial evaluating the safety and feasibility of durvalumab treatment at the recommended dose of 1500 mg Q4W in HIV+ cancer patients with solid tumors. Secondary endpoints include analyses of antitumoral activity in terms of objective response rate and duration of response (DOR). An associated translational sub-study includes the assessment of antiviral activity and the interaction of chronic viral infection with anti-cancer response and drug tolerance. Results: Twenty HIV+ individuals with advanced solid tumors were enrolled (Table). All participants maintained their standard-of-care antiretroviral therapy. Basal plasma viremia was undetectable and CD4+ T-cell count was over 200/mm3. There were no durvalumab-related serious adverse events. Only 8 patients (40%) presented drug-related adverse events (all grade 1-2) including diarrhea (15%), rash (15%), nausea (15%) and asthenia (10%). Best response includes: partial response in 5 (25%) (4 NSCLC and 1 anal cancer), stable disease in 4 (20%) (3 NSCLC and 1 melanoma) and progression disease in 11 (55%) patients. At data cut-off, 8 patients (40%) remained on therapy for a median of 10.5 months (range: 6-19 m). Median DOR has not been reached (range 1m to 19 m+). Plasma viremia remained suppressed during the study suggesting no viral reactivation upon durvalumab treatment. Conclusions: DURVAST study demonstrates durvalumab safety in HIV+ cancer patients and suggests an excellent tolerance profile. Understanding how chronic viral infection could contribute to a better tolerance towards immune checkpoint inhibitors will open a new way for the development of safer anti-cancer immunotherapy strategies. Clinical trial information: NCT03094286. [Table: see text]

Processing bodies (P-bodies) are cytoplasmatic mRNP granules containing non-translating mRNAs and proteins from the mRNA decay and silencing machineries. The mechanism of P-body assembly has been typically addressed by depleting P-body components. Here we apply a complementary approach and establish an automated cell-based assay platform to screen for molecules affecting P-body assembly. From a unique library of compounds derived from myxobacteria, 30 specifically inhibited P-body assembly. Gephyronic acid A (GA), a eukaryotic protein synthesis inhibitor, showed the strongest effect. GA also inhibited, under stress conditions, phosphorylation of eIF2α and stress granule formation. Other hits uncovered interesting novel links between P-body assembly, lipid metabolism, and internal organelle physiology. The obtained results provide a chemical toolbox to manipulate P-body assembly and function.

Homeostatic proliferation (HSP) is a major mechanism by which long-lived naïve and memory CD4+ T cells are maintained in vivo and suggested to contribute to the persistence of the latent HIV-1 reservoir. However, while many in vitro latency models rely on CD4+ T cells that were initially differentiated via T-cell receptor (TCR) stimulation into memory/effector cells, latent infection of naïve resting CD4+ T cells maintained under HSP conditions has not been fully addressed. Here, we describe an in vitro HSP culture system utilizing the cytokines IL-7 and IL-15 that allows studying latency in naïve resting CD4+ T cells. CD4+ T cells isolated from several healthy donors were infected with HIV pseudotypes expressing GFP and cultured under HSP conditions or TCR conditions as control. Cell proliferation, phenotype, and GFP expression were analyzed by flow cytometry. RNA expression was quantified by qRT-PCR. Under HSP culture conditions, latently HIV-1 infected naïve cells are in part maintained in the non-dividing (= resting) state. Although a few HIV-1 provirus+ cells were present in these resting GFP negative cells, the estimated level of GFP transcripts per infected cell seems to indicate a block at the post-transcriptional level. Interestingly, neither TCR nor the prototypic HDAC inhibitor SAHA were able to reactivate HIV-1 provirus from these cells. This lack of reactivation was not due to methylation of the HIV LTR. These results point to a mechanism of HIV control in HSP-cultured resting naïve CD4+ T cells that may be distinct from that in TCR-stimulated memory/effector T cells. This work was supported by Grants from the Ministry of Health, Labor and Welfare in Japan for AIDS Research and from the Japan Agency for Medical Research and Development, AMED (YT-Y). JM and AM were funded by a grant from the Spanish Ministry of Economy and Competitiveness and FEDER (Grant no. SAF2013-46077-R).

Homeostatic proliferation (HSP) is a major mechanism by which long-lived naïve and memory CD4+ T cells are maintained in vivo and suggested to contribute to the persistence of the latent HIV-1 reservoir. However, while many in vitro latency models rely on CD4+ T cells that were initially differentiated via T-cell receptor stimulation (TCR) into memory/effector cells, latent infection of naïve resting CD4+ T cells maintained under HSP conditions has not been fully addressed. Here we describe an in vitro HSP culture system utilizing the cytokines IL-7 and IL-15 that allows studying latency in naïve resting CD4+ T cells. CD4+ T cells isolated from several healthy donors were infected with HIV pseudotypes expressing GFP and cultured under HSP conditions or TCR conditions as control. Cell proliferation, phenotype and GFP expression were analyzed by flow cytometry. RNA expression was quantified by qRT-PCR. Under HSP culture conditions, latently HIV-1 infected naïve cells are in part maintained in the non-dividing (= resting) state. Although a few HIV-1 provirus+ cells were present in these resting GFP negative cells, the estimated level of GFP transcripts per infected cell seems to indicate a block at the post-transcriptional level. Interestingly, neither TCR nor the prototypic HDAC inhibitor SAHA were able to reactivate HIV-1 provirus from these cells. This lack of reactivation was not due to methylation of the HIV LTR. These results point to a mechanism of HIV control in HSP-cultured resting naïve CD4+ T cells that may be distinct from that in TCR-stimulated memory/effector T cells.

Single nucleotide polymorphisms (SNPs) located in the chromosome region 17q12-q21 are risk factors for asthma. Particularly, there are cis-regulatory haplotypes within this region that regulate differentially the expression levels of ORMDL3, GSDMB and ZPBP2 genes. Remarkably, ORMDL3 has been shown to modulate lymphocyte activation parameters in a heterologous expression system. In this context, it has been shown that Th2 and Th17 cytokine production is affected by SNPs in this region. Therefore, we aim to assess the impact of hereditary components within region 17q12-q21 on the activation profile of human T lymphocytes, focusing on the haplotype formed by allelic variants of SNPs rs7216389 and rs12936231. We measured calcium influx and activation markers, as well as the proliferation rate upon T cell activation. Haplotype-dependent differences in mRNA expression levels of IL-2 and INF-γ were observed at early times after activation. In addition, the allelic variants of these SNPs impacted on the extent of calcium influx in resting lymphocytes and altered proliferation rates in a dose dependent manner. As a result, the asthma risk haplotype carriers showed a lower threshold of saturation during activation. Finally, we confirmed differences in activation marker expression by flow cytometry using phytohemagglutinin, a strong polyclonal stimulus. Altogether, our data suggest that the genetic component of pro-inflammatory pathologies present in this chromosome region could be explained by different T lymphocyte activation dynamics depending on individual allelic heredity. This work was supported by grants from the Spanish Ministry of Economy and Competitiveness (SAF2010-16725, SAF2013-46077-R, SAF2014-52228-R, BES-2011-043839), Fondo de Investigación Sanitaria (Red HERACLES RD12/0042/0014), Fundació la Marató de TV3 (20134030) and Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT 3150113). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

The ELISpot assay is used for the detection of T cell responses in clinical trials and vaccine evaluations. Standardization and reproducibility are necessary to compare the results worldwide, inter- and intra-assay variability being critical factors. To assure operator safety as well as high-quality experiment performance, the ELISpot assay was implemented on an automated liquid handling platform, a Tecan Freedom EVO. After validation of the liquid handling, automated loading of plates with cells and reagents was investigated. With step by step implementation of the manual procedure and liquid dispensing optimization on the robot platform, a fully automated ELISpot assay was accomplished with plates remaining in the system from the plate blocking step to spot development. The mean delta difference amounted to a maximum of 6%, and the mean dispersion was smaller than in the manual assay. Taken together, we achieved with this system not only a lower personnel attendance but also higher throughput and a more precise and parallelized analysis. This platform has the potential to guarantee validated, safe, fast, reproducible and cost-efficient immunological and toxicological assays in the future. Funding was provided by Ministerium für Wirtschaft, Arbeit, Energie und Verkehr des Saarlandes (Grant Nos. C71-LdZ-2011, 01/2014), Spanish Ministry of Economy and Competitiveness and FEDER (Grant No. SAF2013-46077-R).

Targeting a host factor essential for the replication of different viruses but not for the cells offers a higher genetic barrier to the development of resistance, may simplify therapy regimens for coinfections, and facilitates management of emerging viral diseases. DEAD-box polypeptide 3 (DDX3) is a human host factor required for the replication of several DNA and RNA viruses, including some of the most challenging human pathogens currently circulating, such as HIV-1, Hepatitis C virus, Dengue virus, and West Nile virus. Herein, we showed for the first time, to our knowledge, that the inhibition of DDX3 by a small molecule could be successfully exploited for the development of a broad spectrum antiviral agent. In addition to the multiple antiviral activities, hit compound 16d retained full activity against drug-resistant HIV-1 strains in the absence of cellular toxicity. Pharmacokinetics and toxicity studies in rats confirmed a good safety profile and bioavailability of 16d. Thus, DDX3 is here validated as a valuable therapeutic target.

BACKGROUND: Regulatory B (Breg) and T (Treg) cells represent a biomarker for tolerance in transplant patients. Despite the importance of Treg and Breg in transplantation and the suggested crosstalk between both suppressive cell populations, little is known on how they are influenced by long-term immunosuppressive treatment. The aim of the present study was to investigate the effect of different immunosuppressive drugs used in routine clinical practice on Treg and Breg cell numbers. METHODS: Thirty-six kidney transplant recipients with stable graft function were recruited and classified according to their concomitant therapy: 22 patients received calcineurin inhibitors (CNI) and 14 patients received mammalian target of rapamycin (mTOR) inhibitors. A group of 8 healthy untreated subjects was included as control. Absolute numbers of peripheral blood-derived IL10-producing B cells (CD19(+)IL10(+)), CD19(+)CD24(hi)CD38(hi) transitional B cells and Treg cells (CD4(+)CD25(+)FOXP3(+)) were quantified in all KT patients and controls by flow cytometry. RESULTS: CD19(+)CD24(hi)CD38(hi) transitional B cells increased over time and seem to be related with long-term therapeutic graft survival irrespective of the treatment regimen. CNI and mTOR inhibitors significantly reduced numbers of Breg cells when compared with healthy individuals, whereas mTOR inhibitors expanded Treg cells in comparison with CNI drugs. CONCLUSIONS: Bridging the drug-mediated reduction of Breg cell numbers in vivo with the requirements of Breg cells for long-term transplant success remains an as yet unresolved task for therapeutic intervention. Further larger cohort studies that evaluate the effect of different treatment regimen on defined lymphocyte subpopulations are warranted. DR and MC were supported by a grant Marató TV3 137/C/2012. JP was supported by grants/nFIS-ISCIII-FEDER PI13/00598 and RedinRenRD12/0021/0024. AM was supported by a Ministerio de Economía y Competitividad grant SAF2010–21336.

A fraction of HIV-1 patients are able to generate broadly neutralizing antibodies (bNAbs) after 2 to 4 years of infection. In rare occasions such antibodies are observed close to the first year of HIV-1 infection but never within the first 6 months. In this study, we analyzed the neutralization breadth of sera from 157 antiretroviral-naive individuals who were infected for less than 1 year. A range of neutralizing activities was observed with a previously described panel of six recombinant viruses from five different subtypes (M. Medina-Ramirez et al., J Virol 85: 5804–5813, 2011, http://dx.doi.org/10.1128/JVI.02482-10 ). Some sera were broadly reactive, predominantly targeting envelope epitopes within the V2 glycan-dependent region. The neutralization breadth was positively associated with time postinfection ( P = 0.0001), but contrary to what has been reported for chronic infections, no association with the viral load was observed. Notably, five individuals within the first 6 months of infection (two as early as 77 and 96 days postinfection) showed substantial cross-neutralization. This was confirmed with an extended panel of 20 Env pseudoviruses from four different subtypes (two in tier 3, 14 in tier 2, and four in tier 1). Sera from these individuals were capable of neutralizing viruses from four different subtypes with a geometric mean 50% infective dose (ID 50 ) between 100 and 800. These results indicate that induction of cross-neutralizing responses, albeit rare, is achievable even within 6 months of HIV-1 infection. These observations encourage the search for immunogens able to elicit this kind of response in preventive HIV-1 vaccine approaches. IMPORTANCE There are very few individuals able to mount broadly neutralizing activity (bNA) close to the first year postinfection. It is not known how early in the infection cross-neutralizing responses can be induced. In the present study, we show that bNAbs, despite being rare, can be induced much earlier than previously thought. The identification of HIV-1-infected patients with these activities within the first months of infection and characterization of these responses will help in defining new immunogen designs and neutralization targets for vaccine-mediated induction of bNAbs.

Hepatitis C virus (HCV) infection is the leading cause of chronic liver diseases. Water extracts of the leaves of the wild Egyptian artichoke (WEA) [ Cynara cardunculus L. var. sylvestris (Lam.) Fiori] have been used for centuries in the Sinai Peninsula to treat hepatitis symptoms. Here we isolated and characterized six compounds from the water extracts of WEA and evaluated their HCV inhibition capacities in vitro . Importantly, two of these compounds, grosheimol and cynaropicrin, inhibited HCV with half-maximal effective concentrations (EC 50 s) in the low micromolar range. They inhibited HCV entry into target cells and were active against both cell-free infection as well as cell-cell transmission. Furthermore, the antiviral activity of both compounds was pan-genotypic as HCV genotypes 1a, 1b, 2b, 3a, 4a, 5a, 6a, and 7a were inhibited. Thus, grosheimol and cynaropicrin are promising candidates for the development of new pan-genotypic entry inhibitors of HCV infection. IMPORTANCE Because there is no preventive HCV vaccine available today, the discovery of novel anti-HCV cell entry inhibitors could help develop preventive measures against infection. The present study describes two compounds isolated from the wild Egyptian artichoke (WEA) with respect to their structural elucidation, absolute configuration, and quantitative determination. Importantly, both compounds inhibited HCV infection in vitro . The first compound was an unknown molecule, and it was designated “grosheimol,” while the second compound is the known molecule cynaropicrin. Both compounds belong to the group of sesquiterpene lactones. The mode of action of these compounds occurred during the early steps of the HCV life cycle, including cell-free and cell-cell infection inhibition. These natural compounds present promising candidates for further development into anti-HCV therapeutics.

OBJECTIVE To assess the effect of antigen-exposure on the T-cell repertoire in the chronic phase of HIV-infection. DESIGN This is a prospective cross-sectional study. METHODS HIV-seropositive patients and immunocompetent controls from tuberculosis low and high-endemic countries were recruited. Mycobacterium tuberculosis (purified protein derivative; PPD)-specific CD4 T-cell responses were quantified directly from whole blood using flow-cytometric analysis of intracellular cytokines after specific stimulation. T-cell reactivity toward cytomegalovirus (CMV) or Staphylococcus aureus Enterotoxin B (SEB) served as control. RESULTS In a low-endemic region, HIV-seropositive patients showed lower frequencies of PPD-specific T cells compared to immunocompetent individuals. This was not due to a general loss of immunity toward recall antigens, as T-cell immunity toward CMV or SEB was preserved. In line with continuous antigen exposure, HIV-seropositive patients from a high-endemic region showed preserved PPD-specific T-cell frequencies that were not different from those found in HIV-seronegative controls. Likewise, both groups did not differ in recall T-cell responses toward CMV or SEB. CONCLUSION A lower prevalence and frequency of PPD-specific immunity is a typical feature of HIV-related immunosuppression in low-endemic regions. In contrast, PPD-specific responses are maintained in HIV-seropositive individuals in regions with high tuberculosis prevalence. This suggests constant skewing and restriction of specific T-cell immunity toward environmental antigens in HIV-seropositive individuals.

Some key features of a mathematical description of an immune response are an estimate of the number of responding cells and the manner in which those cells divide, differentiate, and die. The intracellular dye CFSE is a powerful experimental tool for the analysis of a population of dividing cells, and numerous mathematical treatments have been aimed at using CFSE data to describe an immune response [30,31,32,37,38,42,48,49]. Recently, partial differential equation structured population models, with measured CFSE fluorescence intensity as the structure variable, have been shown to accurately fit histogram data obtained from CFSE flow cytometry experiments [18,19,52,54]. In this report, the population of cells is mathematically organized into compartments, with all cells in a single compartment having undergone the same number of divisions. A system of structured partial differential equations is derived which can be fit directly to CFSE histogram data. From such a model, cell counts (in terms of the number of divisions undergone) can be directly computed and thus key biological parameters such as population doubling time and precursor viability can be determined. Mathematical aspects of this compartmental model are discussed, and the model is fit to a data set. As in [18,19], we find temporal and division dependence in the rates of proliferation and death to be essential features of a structured population model for CFSE data. Variability in cellular autofluorescence is found to play a significant role in the data, as well. Finally, the compartmental model is compared to previous work, and statistical aspects of the experimental data are discussed.

The 1'-organyl-1,2,3,4-tetrahydrospiro[naphthalene-1,4'-piperidine] derivatives 1 a-4 a [for which organyl=benzyl (1 a), 4-methoxybenzyl (2 a), 2-phenylethyl (3 a), or 3-methylbut-2-enyl (4 a)] are high-affinity, selective σ₁ ligands. The corresponding sila-analogues 1 b-4 b (replacement of the carbon spirocenter with a silicon atom) were synthesized in multistep syntheses, starting from dichlorodivinylsilane, and were isolated as the hydrochlorides 1 b⋅HCl-4 b⋅HCl. Compounds 1 a⋅HCl-4 a⋅HCl and 1 b⋅HCl-4 b⋅HCl were structurally characterized by NMR spectroscopy (¹H, ¹³C, ²⁹Si) in solution, and the C/Si analogues 3 a⋅HCl and 3 b⋅HCl were studied by single-crystal X-ray diffraction. These structural investigations were complemented by computational studies. The σ₁ and σ₂ receptor affinities of the C/Si pairs 1 a/1 b-4 a/4 b were studied with radioligand binding assays. The σ₁ receptor affinity of the silicon compounds 1 b-4 b is slightly higher than that of the corresponding carbon analogues 1 a-4 a. Because affinity for the σ₂ receptor is decreased by the C/Si exchange, the σ₁/σ₂ selectivity of the silicon compounds is considerably improved, indicating that the C→Si switch strategy is a powerful tool for modulating both pharmacological potency and selectivity.

Advances in fluorescent labeling of cells as measured by flow cytometry have allowed for quantitative studies of proliferating populations of cells. The investigations (Luzyanina et al. in J. Math. Biol. 54:57-89, 2007; J. Math. Biol., 2009; Theor. Biol. Med. Model. 4:1-26, 2007) contain a mathematical model with fluorescence intensity as a structure variable to describe the evolution in time of proliferating cells labeled by carboxyfluorescein succinimidyl ester (CFSE). Here, this model and several extensions/modifications are discussed. Suggestions for improvements are presented and analyzed with respect to statistical significance for better agreement between model solutions and experimental data. These investigations suggest that the new decay/label loss and time dependent effective proliferation and death rates do indeed provide improved fits of the model to data. Statistical models for the observed variability/noise in the data are discussed with implications for uncertainty quantification. The resulting new cell dynamics model should prove useful in proliferation assay tracking and modeling, with numerous applications in the biomedical sciences.

The Global HIV Vaccine Research Cryorepository (GHRC) is an international consortium coordinated by the Fraunhofer Institute for Biomedical Engineering (Fraunhofer IBMT) and funded by the Bill & Melinda Gates Foundation. It is one of the Centralized Service Facilities of the Collaboration for AIDS Vaccine Discovery (CAVD) whose goal is to discover and design a safe and effective preventive vaccine against HIV/AIDS by means of collaborative and comparative research, supported by the utilization of innovative concepts and new technologies. In this context, GHRC has established the first large-scale centralized biobank for low-temperature storage of HIV-1 related specimens and reagents where samples can be long-term cryopreserved under controlled low-temperature conditions and shared among the CAVD laboratories. GHRC develops novel procedures and helpful technology for optimized sample processing and cryopreservation of clinical specimens collected by CAVD and for the storage of relevant reagents. Key elements of the GHRC technology platform are new cryosubstrates with integrated non-volatile memory chips, the specimen knowledge and preparation workflow management system ChameleonLab, high precision and high throughput controlled-rate freezers integrated in cryoworkbenches, sample access towers shielding cryotanks from ambient air and an electronic cryotank infrastructure allowing accurate sample localization and selective data access even under cryogenic temperatures. To ease collaborative research, a web portal for online registration of HIV specimens has been established enhancing the GHRC central information and specimen administration database. Moreover, GHRC has proved to be well-suited for pseudotype virus stock production and has implemented an appropriate automated large-scale production system.

The gentle and careful in vitro processing of live cells is essential in order to make them available to future therapeutic applications. We present a protocol for the activation of single-T cells based on the contact formation with individual anti-CD3/anti-CD28 presenting microbeads in a lab-on-chip environment. The chips consist of microfluidic channels and microelectrodes for performing dielectrophoretic manipulation employing a.c. electric fields. The dielectrophoretic guiding elements allow the assembly of cell-bead pairs while avoiding ill-defined physical contacts with their environment. After overnight cultivation of the manipulated cells, 77% of the bead-associated T cells expressed the activation marker molecule CD69. Physiological stress on the cells was shown to be mainly due to the single-cell cultivation and not to the manipulation in the chips. The same approach could be useful for the in vitro regulation of stem cell differentiation.

PURPOSE: Intima-media thickness (IMT) of the common carotid artery and the resistive index (RI) of the internal carotid artery correlate with the degree of atherosclerosis and are predictors of cardiovascular morbidity and mortality. Limited or no data are available about long-term predictive values and the progression of the two markers themselves. MATERIALS AND METHODS: 145 patients with at least one cardiovascular risk factor or clinically manifest atherosclerosis were included. At enrollment and after 36 and 74 months, duplex sonographic measurements of IMT CCA and RI ICA were performed. During follow-up, the occurrence of cardiovascular events (cardiovascular death, myocardial infarction, stroke) was assessed. RESULTS: At baseline, IMT was 0.79 +/- 0.16 mm and RI 0.66 +/- 0.08. Log-rank analysis showed a continuous increase in the risk of a cardiovascular event with an increasing range of IMT (p = 0.011) and RI (p = 0.006). IMT progression in patients with low versus high atherosclerotic burden (as defined by SMART score 7 points) differs significantly (32 +/- 83 microm versus 95 +/- 125 microm; p > 0.002). IMT progression was even more pronounced in patients suffering a cardiovascular event (141 +/- 105 microm versus 54 +/- 111 microm; p > 0.001). No significant RI ICA progression could be detected during follow-up in any group (patients with low vs. high atherosclerotic burden 0.00 +/- 0.06 versus 0.00 +/- 0.04; p = n. s.; patients with vs. without cardiovascular event 0.00 +/- 0.05 versus 0.01 +/- 0.03; p = n. s.). CONCLUSION: Our results confirm the predictive value for cardiovascular events of RI and IMT in long-term follow-up. In contrast to RI, IMT increases over six years, above all in patients suffering a cardiovascular event. The results suggest that IMT is suitable for cardiovascular risk prediction as well as for progression measurements, while RI cannot be recommended for progression measurements. The effect of drug therapy on RI needs furth clarification.

The positive transcription elongation factor b (P-TEFb) is a heterodimeric complex composed of cyclin-dependent kinase 9 and its regulator cyclin T1/2. It stimulates transcription elongation by phosphorylation of serine 2 residues in the carboxy-terminal domain of polymerase II. 7SK RNA and HEXIM proteins can antagonize transcriptional stimulation by sequestering P-TEFb in a catalytically inactive ribonucleoprotein (RNP). Here, we show that the previously uncharacterized La-related protein 7 (LARP7) has a role in 7SK-mediated regulation of transcription. LARP7 binds to the highly conserved 3′-terminal U-rich stretch of 7SK RNA and is an integral part of the 7SK RNP. On stimulation, LARP7 remains associated with 7SK RNA, whereas P-TEFb is released. Interestingly, reduction of LARP7 by RNA interference enhances transcription from cellular polymerase II promoters, as well as a TAT-dependent HIV-1 promoter. Thus, LARP7 is a negative transcriptional regulator of polymerase II genes, acting by means of the 7SK RNP system.