Thu, 21 Aug 2008 16:18:02 BST CiteULike: Author Brizard http://www.citeulike.org/author/Brizard CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/Pezda/article/3058018 <i>J Immunol, Vol. 171, No. 12. (15 December 2003), pp. 6466-6477.</i><br /><br />We report in this study the generation of a novel rat mAb that recognizes mouse plasmacytoid dendritic cells (pDC). This Ab, named 120G8, stains a small subset of CD11clow spleen cell with high specificity. This population produces high amounts of IFN-alpha upon in vitro viral stimulation. Both ex vivo- and in vitro-derived 120G8+ cells display a phenotype identical with that of the previously described mouse pDC (B220highLy6ChighGr1lowCD11b-CD11clow). Mice treated with 120G8 mAb are depleted of B220highLy6ChighCD11clow cells and have a much-reduced ability to produce IFN-alpha in response to in vivo CpG stimulation. The mAb 120G8 stains all and only B220highLy6ChighCD11clow pDC in all lymphoid organs. Immunohistochemical studies performed with this mAb indicate that pDC are located in the T cell area of spleen, lymph nodes, and Peyer's patches. Although the Ag recognized by 120G8 is not yet known, we show that its expression is up-regulated by type I IFN on B cells and DC. Using this mAb in immunofluorescence studies demonstrates strain- and organ-specific differences in the frequency of pDC and other DC subsets. 129Sv mice have a much higher frequency of pDC, together with a lower frequency of conventional CD8alpha+CD11chigh DC, compared with C57BL/6 mice, both in spleen and blood. The higher ability of 129Sv mice to produce IFN-alpha in vivo is related to a higher number of pDC, but also to a higher ability of pDC from 129Sv mice to produce IFN-alpha in vitro in response to viral stimulation. Mouse Strain Differences in Plasmacytoid Dendritic Cell Frequency and Function Revealed by a Novel Monoclonal Antibody Carine Asselin-Paturel Geraldine Brizard Jean-Jacques Pin Francine Briere Giorgio Trinchieri J Immunol, Vol. 171, No. 12. (15 December 2003), pp. 6466-6477. 2008-07-30T00:36:13-00:00 2003 J Immunol 171 12 6466 6477 120g8 antibody dc plasmacytoid http://www.citeulike.org/user/Pezda/article/3054943 <i>J Immunol, Vol. 175, No. 10. (15 November 2005), pp. 6723-6732.</i><br /><br />Antiviral immunity requires early and late mechanisms in which IFN-alpha and IL-12 play major roles. However, the initial events leading to their production remain largely unclear. Given the crucial role of TLR in innate recognition, we investigated their role in antiviral immunity in vivo. Upon murine CMV (MCMV) infection, both MyD88-/- and TLR9-/- mice were more susceptible and presented increased viral loads compared with C57BL/6, TLR2-/-, TLR3-/-, or TLR4-/- mice. However, in terms of resistance to infection, IFN-alpha production and in many other parameters of early inflammatory responses, the MyD88-/- mice showed a more defective response than TLR9-/- mice. In the absence of the TLR9/MyD88 signaling pathway, cytokine production was dramatically impaired with a complete abolition of bioactive IL-12p70 serum release contrasting with a high flexibility for IFN-alpha release, which is initially (36 h) plasmacytoid dendritic cell- and MyD88-dependent, and subsequently (44 h) PDC-, MyD88-independent and, most likely, TLR-independent. NK cells from MCMV-infected MyD88-/- and TLR9-/- mice displayed a severely impaired IFN-gamma production, yet retained enhanced cytotoxic activity. In addition, dendritic cell activation and critical inflammatory cell trafficking toward the liver were still effective. In the long term, except for isotype switching to MCMV-specific IgG1, the establishment of Ab responses was not significantly altered. Thus, our results demonstrate a critical requirement of TLR9 in the process of MCMV sensing to assure rapid antiviral responses, coordinated with other TLR-dependent and -independent events that are sufficient to establish adaptive immunity. MyD88-Dependent and -Independent Murine Cytomegalovirus Sensing for IFN-alpha Release and Initiation of Immune Responses In Vivo Thomas Delale Andre Paquin Carine Asselin-Paturel Marc Dalod Geraldine Brizard Elizabeth Bates Philippe Kastner Susan Chan Shizuo Akira Alain Vicari Christine Biron Giorgio Trinchieri Francine Briere J Immunol, Vol. 175, No. 10. (15 November 2005), pp. 6723-6732. 2008-07-28T23:55:18-00:00 2005 J Immunol 175 10 6723 6732 immune_response innate_immunity mcmv myd88 tlr2 tlr3 tlr4 tlr9 http://www.citeulike.org/user/AlfonsoVicenteSuarez/article/329642 <i>Nature Immunology, Vol. 6, No. 10. (04 September 2005), pp. 1011-1019.</i> Interaction between conventional dendritic cells and natural killer cells is integral to the activation of effective antiviral immunity Christopher Andoniou Serani van Dommelen Valentina Voigt Daniel Andrews Geraldine Brizard Carine Asselin-Paturel Thomas Delale Katryn Stacey Giorgio Trinchieri Mariapia Degli-Esposti doi:10.1038/ni1244 Nature Immunology, Vol. 6, No. 10. (04 September 2005), pp. 1011-1019. 2005-09-22T05:54:07-00:00 2005 Nature Immunology 1529-2908 6 10 1011 1019 Nature Publishing Group ra rae-1 http://www.citeulike.org/user/arichar6/article/472576 <i>Physics of Plasmas, Vol. 10, No. 5. (2003), pp. 2147-2154.</i><br /><br />A tutorial introduction to the topic of linear wave conversion in multiple spatial dimensions is provided. The emphasis is on physical concepts, particularly those features of multidimensional conversion that are new and different from the more familiar "mode conversion" problem in one spatial dimension. After introductory comments, a brief review of WKB theory for vector wave equations in the absence of conversion is provided in order to introduce notation, terminology, and geometrical ideas. A primary theme of the discussion is that, although WKB (ray-based) methods break down in conversion regions, the ray geometry in the conversion region can be used to develop local wave equations that govern the two coupled wave channels undergoing conversion. These methods can be incorporated into ray-tracing algorithms providing, for the first time, the ability to follow the "ray splitting" associated with linear conversion in multidimensions, including the amplitude and phase changes associated with the conversion. ©2003 American Institute of Physics. Ray-based methods in multidimensional linear wave conversion Eugene Tracy Allan Kaufman Alain Brizard doi:10.1063/1.1543579 Physics of Plasmas, Vol. 10, No. 5. (2003), pp. 2147-2154. 2006-01-20T15:56:51-00:00 2003 Physics of Plasmas 10 5 2147 2154 AIP mode-conversion plasma-physics ray-tracing http://www.citeulike.org/user/arichar6/article/472573 <i>Physics of Plasmas, Vol. 12, No. 2. (2005)</i><br /><br />The process of resonant wave conversion (often called linear mode conversion) has traditionally been analyzed with a spatially one-dimensional slab model, for which the rays propagate in a two-dimensional phase space. However, it has recently been shown [E. R. Tracy and A. N. Kaufman, Phys. Rev. Lett. 91, 130402 (2003)] that multidimensional rays have a helical structure for conversion in two or more spatial dimensions (if their dispersion matrix is generic). In that case, a one-dimensional model is inadequate; a correct analysis requires two spatial dimensions and, thus, four-dimensional phase space. A cold-plasma model is introduced in this paper which exhibits ray helicity in conversion regions where the density and magnetic field gradients are significantly nonparallel. For illustration, such regions are identified in a model of the poloidal plane of a deuterium-tritium tokamak plasma. In each conversion region, characterized by a six-sector topology, rays in the sector for incident and reflected magnetosonic waves exhibit significant helicity. A detailed analytic and numerical study of helical rays in this sector is developed for a "symmetric-wedge" model. ©2005 American Institute of Physics Helical rays in two-dimensional resonant wave conversion Allan Kaufman Eugene Tracy Alain Brizard doi:10.1063/1.1835980 Physics of Plasmas, Vol. 12, No. 2. (2005) 2006-01-20T15:55:20-00:00 2005 Physics of Plasmas 12 2 AIP helical mode-conversion plasma-physics ray-tracing