Browsing by Subject "VECTOR"

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Now showing items 1-11 of 11
  • Khattab, Ayman; Barroso, Marta; Miettinen, Tiera; Meri, Seppo (2015)
  • Balboa, Diego; Weltner, Jere; Eurola, Solja; Trokovic, Ras; Wartiovaara, Kirmo; Otonkoski, Timo (2015)
    CRISPR/Cas9 protein fused to transactivation domains can be used to control gene expression in human cells. In this study, we demonstrate that a dCas9 fusion with repeats of VP16 activator domains can efficiently activate human genes involved in pluripotency in various cell types. This activator in combination with guide RNAs targeted to the OCT4 promoter can be used to completely replace transgenic OCT4 in human cell reprogramming. Furthermore, we generated a chemically controllable dCas9 activator version by fusion with the dihydrofolate reductase (DHFR) destabilization domain. Finally, we show that the destabilized dCas9 activator can be used to control human pluripotent stem cell differentiation into endodermal lineages.
  • Heitmann, A.; Jansen, S.; Luehken, R.; Leggewie, M.; Badusche, M.; Pluskota, B.; Becker, N.; Vapalahti, O.; Schmidt-Chanasit, J.; Tannich, E. (2017)
    Mosquitoes collected in Germany in 2016, including Culex pipiens pipiens biotype pipiens, Culex torrentium and Aedes albopictus, as well as Culex pipiens pipiens biotype molestus (in colony since 2011) were experimentally infected with Zika virus (ZIKV) at 18 degrees C or 27 degrees C. None of the Culex taxa showed vector competence for ZIKV. In contrast, Aedes albopictus were susceptible for ZIKV but only at 27 degrees C, with transmission rates similar to an Aedes aegypti laboratory colony tested in parallel.
  • Leopold, Anna; Verkhusha, Vladislav V. (2020)
    Inhibition of receptor tyrosine kinases (RTKs) by small molecule inhibitors and monoclonal antibodies is used to treat cancer. Conversely, activation of RTKs with their ligands, including growth factors and insulin, is used to treat diabetes and neurodegeneration. However, conventional therapies that rely on injection of RTK inhibitors or activators do not provide spatiotemporal control over RTK signaling, which results in diminished efficiency and side effects. Recently, a number of optogenetic and optochemical approaches have been developed that allow RTK inhibition or activation in cells andin vivowith light. Light irradiation can control RTK signaling non-invasively, in a dosed manner, with high spatio-temporal precision, and without the side effects of conventional treatments. Here we provide an update on the current state of the art of optogenetic and optochemical RTK technologies and the prospects of their use in translational studies and therapy.
  • PHENIX Collaboration; Adare, A.; Kim, D. J.; Novitzky, N.; Rak, J. (2018)
    The PHENIX experiment at the Relativistic Heavy Ion Collider has measured the differential cross section of phi(1020)-meson production at forward rapidity in p + p collisions at root s = 510 GeV via the dimuon decay channel. The partial cross section in the rapidity and P-T ranges 1.2 <vertical bar y vertical bar <2.2 and 2 <p(T) <7 GeV/c is sigma(phi) = [2.28 +/- 0.09(stat) +/- 0.14(syst) +/- 0.27(norm)] x 10(-2) mb. The energy dependence of sigma(phi )(1.2 <vertical bar y vertical bar <2.2,2 <p(T) <5 GeV/c) is studied using the PHENIX measurements at root s = 200 and 510 GeV and the Large Hadron Collider measurements at root s = 2.76 and 7 TeV. The experimental results arc compared to various event generator predictions (PYTHIA6, PYTHIA8, PHOJET, AMPT, EPOS3, and EPOS-LHC).
  • Bäck, Susanne; Dossat, Amanda; Parkkinen, Ilmari; Koivula, Pyry; Airavaara, Mikko; Richie, Christopher T.; Chen, Yun-Hsiang; Wang, Yun; Harvey, Brandon K. (2019)
    The cytomegalovirus (CMV) immediate early promoter has been extensively developed and exploited for transgene expression in vitro and in vivo, including human clinical trials. The CMV promoter has long been considered a stable, constitutive and ubiquitous promoter for transgene expression. Using two different CMV-based promoters, we found an increase in CMV-driven transgene expression in the rodent brain and in primary neuronal cultures in response to methamphetamine, glutamate, kainic acid, and activation of G-protein coupled receptor signaling using designer receptors exclusively activated by designer drugs (DREADDs). In contrast, promoters derived from human synapsin 1 (hSyn1) gene or elongation factor 1a (EF1a) did not exhibit altered transgene expression in response to the same neuronal stimulation. Overall, our results suggest that the long standing assertion that the CMV promoter confers constitutive expression in neurons should be reevaluated and future studies should evaluate the activity of the CMV promoter in a given application.
  • Uusitalo, Ruut; Siljander, Mika; Linden, Andreas; Sormunen, Jani J.; Aalto, Juha; Hendrickx, Guy; Kallio, Eva; Vajda, Andrea; Gregow, Hilppa; Henttonen, Heikki; Marsboom, Cedric; Korhonen, Essi M.; Sironen, Tarja; Pellikka, Petri; Vapalahti, Olli (2022)
    Background Ticks are responsible for transmitting several notable pathogens worldwide. Finland lies in a zone where two human-biting tick species co-occur: Ixodesricinus and Ixodespersulcatus. Tick densities have increased in boreal regions worldwide during past decades, and tick-borne pathogens have been identified as one of the major threats to public health in the face of climate change. Methods We used species distribution modelling techniques to predict the distributions of I.ricinus and I.persulcatus, using aggregated historical data from 2014 to 2020 and new tick occurrence data from 2021. By aiming to fill the gaps in tick occurrence data, we created a new sampling strategy across Finland. We also screened for tick-borne encephalitis virus (TBEV) and Borrelia from the newly collected ticks. Climate, land use and vegetation data, and population densities of the tick hosts were used in various combinations on four data sets to estimate tick species' distributions across mainland Finland with a 1-km resolution. Results In the 2021 survey, 89 new locations were sampled of which 25 new presences and 63 absences were found for I.ricinus and one new presence and 88 absences for I.persulcatus. A total of 502 ticks were collected and analysed; no ticks were positive for TBEV, while 56 (47%) of the 120 pools, including adult, nymph, and larva pools, were positive for Borrelia (minimum infection rate 11.2%, respectively). Our prediction results demonstrate that two combined predictor data sets based on ensemble mean models yielded the highest predictive accuracy for both I.ricinus (AUC = 0.91, 0.94) and I.persulcatus (AUC = 0.93, 0.96). The suitable habitats for I.ricinus were determined by higher relative humidity, air temperature, precipitation sum, and middle-infrared reflectance levels and higher densities of white-tailed deer, European hare, and red fox. For I.persulcatus, locations with greater precipitation and air temperature and higher white-tailed deer, roe deer, and mountain hare densities were associated with higher occurrence probabilities. Suitable habitats for I.ricinus ranged from southern Finland up to Central Ostrobothnia and North Karelia, excluding areas in Ostrobothnia and Pirkanmaa. For I.persulcatus, suitable areas were located along the western coast from Ostrobothnia to southern Lapland, in North Karelia, North Savo, Kainuu, and areas in Pirkanmaa and Paijat-Hame. Conclusions This is the first study conducted in Finland that estimates potential tick species distributions using environmental and host data. Our results can be utilized in vector control strategies, as supporting material in recommendations issued by public health authorities, and as predictor data for modelling the risk for tick-borne diseases.
  • Kadekar, S; Nawale, GN; Rangasami, VK; Le Joncour, V; Laakkonen, P; Hilborn, J; Varghese, OP; Oommen, OP (2021)
    There is an unmet need to develop strategies that allow site-specific delivery of short interfering RNA (siRNA) without any associated toxicity. To address this challenge, we have developed a novel siRNA delivery platform using chemically modified pluronic F108 as an amphiphilic polymer with a releasable bioactive disulfide functionality. The micelles exhibited thermoresponsive properties and showed a hydrodynamic size of similar to 291 nm in DLS and similar to 200-250 nm in SEM at 37 degrees C. The grafting of free disulfide pyridyl groups enhanced the transfection efficiency and was successfully demonstrated in human colon carcinoma (HCT116; 88%) and glioma cell lines (U87; 90%), non-cancerous human dermal fibroblast (HDF; 90%) cells as well as in mouse embryonic stem (mES; 54%) cells. To demonstrate the versatility of our modular nanocarrier design, we conjugated the MDGI receptor targeting COOP peptide on the particle surface that allowed the targeted delivery of the cargo molecules to human patent-derived primary BT-13 gliospheres. Transfection experiments with this design resulted in similar to 65% silencing of STAT3 mRNA in BT-13 gliospheres, while only similar to 20% of gene silencing was observed in the absence of the peptide. We believe that our delivery method solves current problems related to the targeted delivery of RNAi drugs for potential in vivo applications.
  • Weltner, Jere; Trokovic, Ras (Humana press, 2021)
    Methods in Molecular Biology
    CRISPR-mediated gene activation (CRISPRa) can be used to target endogenous genes for activation. By targeting pluripotency-associated reprogramming factors, human fibroblasts can be reprogrammed into induced pluripotent stem cells (iPSCs). Here, we describe a method for the derivation of iPSCs from human fibroblasts using episomal plasmids encoding CRISPRa components. This chapter also provides procedure to assemble guide RNA cassettes and generation of multiplexed guide plasmids for readers who want to design their own guide RNAs.
  • Jalil, Sami; Keskinen, Timo; Maldonado Sartori, Rocio; Sokka, Juho Joonas; Trokovic, Ras; Otonkoski, Timo; Wartiovaara, Kirmo (2021)
    Human induced pluripotent stem cells (hiPSCs) allow in vitro study of genetic diseases and hold potential for personalized stem cell therapy. Gene editing, precisely modifying specifically targeted loci, represents a valuable tool for different hiPSC applications. This is especially useful in monogenic diseases to dissect the function of unknown mutations or to create genetically corrected, patient-derived hiPSCs. Here we describe a highly efficient method for simultaneous base editing and reprogramming of fibroblasts employing a CRISPR-Cas9 adenine base editor. As a proof of concept, we apply this approach to generate gene-edited hiPSCs from skin biopsies of four patients carrying a Finnish-founder pathogenic point mutation in either NOTCH3 or LDLR genes. We also show LDLR activity restoration after the gene correction. Overall, this method yields tens of gene-edited hiPSC monoclonal lines with unprecedented efficiency and robustness while considerably reducing the cell culture time and thus the risk for in vitro alterations.
  • Bennett, Ed; Hong, Deog Ki; Lee, Jong-Wan; Lin, C.-J. David; Lucini, Biagio; Mesiti, Michele; Piai, Maurizio; Rantaharju, Jarno; Vadacchino, Davide (2020)
    We perform lattice studies of meson mass spectra and decay constants of the Sp(4) gauge theory in the quenched approximation. We consider two species of (Dirac) fermions as matter field content, transforming in the 2-index antisymmetric and the fundamental representation of the gauge group, respectively. All matter fields are formulated as Wilson fermions. We extrapolate to the continuum and massless limits and compare to each other the results obtained for the two species of mesons. In the case of two fundamental and three antisymmetric fermions, the long-distance dynamics is relevant for composite Higgs models. This is the first lattice study of this class of theories. The global SU(4)×SU(6) symmetry is broken to the Sp(4)×SO(6) subgroup, and the condensates align with the explicit mass terms present in the lattice formulation of the theory. The main results of our quenched calculations are that, with fermions in the 2-index antisymmetric representation of the group, the masses squared and decay constant squared of all the mesons we considered are larger than the corresponding quantities for the fundamental representation, by factors that vary between ∼1.2 and ∼2.7. We also present technical results that will be useful for future lattice investigations of dynamical simulations, of composite chimera baryons, and of the approach to large N in the Sp(2N) theories considered. We briefly discuss their high-temperature behavior, where symmetry restoration and enhancement are expected.