Direct transfer of viral and cellular proteins from varicella-zoster virus-infected non-neuronal cells to human axons

10.1371/journal.pone.0126081PLoS ONE105e012608

The ALICE experiment at the CERN LHC

ALICE (A Large Ion Collider Experiment) is a general-purpose, heavy-ion detector at the CERN LHC which focuses on QCD, the strong-interaction sector of the Standard Model. It is designed to address the physics of strongly interacting matter and the quark-gluon plasma at extreme values of energy density and temperature in nucleus-nucleus collisions. Besides running with Pb ions, the physics programme includes collisions with lighter ions, lower energy running and dedicated proton-nucleus runs. ALICE will also take data with proton beams at the top LHC energy to collect reference data for the heavy-ion programme and to address several QCD topics for which ALICE is complementary to the other LHC detectors. The ALICE detector has been built by a collaboration including currently over 1000 physicists and engineers from 105 Institutes in 30 countries. Its overall dimensions are 161626 m3 with a total weight of approximately 10 000 t. The experiment consists of 18 different detector systems each with its own specific technology choice and design constraints, driven both by the physics requirements and the experimental conditions expected at LHC. The most stringent design constraint is to cope with the extreme particle multiplicity anticipated in central Pb-Pb collisions. The different subsystems were optimized to provide high-momentum resolution as well as excellent Particle Identification (PID) over a broad range in momentum, up to the highest multiplicities predicted for LHC. This will allow for comprehensive studies of hadrons, electrons, muons, and photons produced in the collision of heavy nuclei. Most detector systems are scheduled to be installed and ready for data taking by mid-2008 when the LHC is scheduled to start operation, with the exception of parts of the Photon Spectrometer (PHOS), Transition Radiation Detector (TRD) and Electro Magnetic Calorimeter (EMCal). These detectors will be completed for the high-luminosity ion run expected in 2010. This paper describes in detail the detector components as installed for the first data taking in the summer of 2008

Centrality evolution of the charged-particle pseudorapidity density over a broad pseudorapidity range in Pb-Pb collisions at root s(NN)=2.76TeV

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RZ-DPSK transmission at 80 Gbit/s channel rate using in-line semiconductor optical amplifiers

We numerically demonstrate the feasibility of return-to-zero differential phase-shift keying transmission at 80 Gbit/s channel rate using cascaded in-line semiconductor optical amplifiers

Feasibility of soliton-like DPSK transmission at 40 Gb/s with in-line semiconductor optical amplifiers

We analyze a soliton-like phase-shift keying 40-Gb/s transmission system using cascaded in-line semiconductor optical amplifiers. Numerical optimization of the proposed soliton-like regime is presented

Multiple VZV-encoded proteins are transferred from VZV-infected MeWo cells to axons.

<p>MeWo cells infected with VZV-ORF10-RFP (A&E), VZV-ORF23-GFP (B&F), VZV-ORF62-GFP (C&G) and VZV-GFP (D&H) cells with were seeded into the axonal compartments of the microfluidic chambers and images were taken at 2 and 18 hpi. All of the fluorescently-tagged viral proteins filled the axons in the axonal compartments at 18, but not 2 hpi (arrowheads). Scale bar: 50 μm.</p

Rapid transfer of protein from VZV-infected MeWo cells to axons.

<p>VZV-GFP-infected MeWo cells were plated in the axonal compartments of microfluidic chambers. The cultures were monitored at the junction of the axonal compartment (lower part of each image) and the microfluidic channel (upper half of each image). By 2 hpi, some axons were diffusely filled with GFP (arrowhead in A). (B) The same compartment at 18 hpi, showing additional GFP-filled axons. C & D depict a chamber where MeWo-GFP cells not infected with VZV were plated into axonal compartments at 2 and 18hpi respectively. Even at 4 dpi, no GFP+ axons were observed (not shown). (E) Time series of images of axons in microfluidic channels 2–6h after plating VZV-GFP infected MeWo cells with hESC-derived axons. At 135 minutes pi a GFP-filled axon was first observed (arrowhead). The direction of GFP filling was from bottom to top, i.e., toward the cell-bodies compartment (top of images) since at 170m pi, the same axon displayed GFP fluorescence throughout the microscopic field (3rd panel of E). At this point in time, another GFP-labeled axon (arrow) had appeared in the field. A few hours later, an additional GFP-filled axon appeared in this microscopic field. Scale bars: 50μm. Cell-bodies are “overexposed” in panels A–D in order to visualize the thin and therefore more weakly fluorescent axons. The time-lapse movie of this experiment is <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0126081#pone.0126081.s001" target="_blank">S1 Movie</a>.</p

Diffusion coefficients of GFP and ORF66-RFP in axons and MeWo cell cytoplasm measured by FRAP.

<p>Diffusion coefficients of GFP and ORF66GFP in axons and MeWo cells measured using FRAP as described in the methods and in the legend to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0126081#pone.0126081.g007" target="_blank">Fig 7</a>.</p><p>Diffusion coefficients of GFP and ORF66-RFP in axons and MeWo cell cytoplasm measured by FRAP.</p

Immunofluorescence evidence of fusion of VZV-infected MeWo cells with axons.

<p>MeWo-GFP cells (green) infected with cell-free VZV66RFP (red) virus were plated into axonal compartments of microfluidic chambers or in glass-bottom culture dishes (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0126081#pone.0126081.g001" target="_blank">Fig 1C</a>). Cultures were fixed and immunostained for the medium neurofilament subunit (NF-M, white) 1 to 3 dpi and nuclei stained with Hoechst (blue). (A–D) Control experiments with uninfected MeWo-GFP cells. No GFP was found in the NF-M+ axons. (E–H) Immunostaining of an axonal compartment where MeWo-GFP cells infected with VZV66RFP were plated 3 days prior to fixation. (E&F) Images showing GFP and ORF66RFP fluorescence, respectively. The arrow points to a syncytium of MeWo cells containing both fluorescent proteins. Arrowheads point to axons showing GFP and RFP signal. (G) shows immunocytochemical staining of this field for NF-M, the syncytium observed in E and F to contain both GFP and RFP is NF-M+ as well (white). H shows a merge of all channels, where both white (NF-M) and yellow (co-expression of GFP and RFP) staining are present in the same polykaryon. (I–L) An axonal compartment with VZV-GFP-infected ARPE cells (green) was immunostained at 4 dpi with anti-NF-H 4142 (red) and anti-VZV gI (white) antibodies. I shows GFP fluorescence and J, the immunostaining for NF-M. Many GFP+/NF-M+ axons (arrowheads) were observed. Some infected ARPE cells (arrow) became neurofilament+ after fusion with axons. The fused ARPE cells and axons were also immunopositive for glycoprotein I (K), but not several other cells that were not part of the polykaryon. Scale bar: 50μm.</p