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31.
López JA Bioley G Turtle CJ Pinzón-Charry A Ho CS Vuckovic S Crosbie G Gilleece M Jackson DC Munster D Hart DN 《Journal of immunological methods》2003,274(1-2):47-61
Dendritic cells (DC) for cancer immunotherapy protocols are generated most commonly by in vitro differentiation of monocytes with exogenous cytokines (Mo-DC). However, Mo-DC differ in their molecular phenotype and function from blood DC (BDC). Clinical isolation of BDC has been limited to the use of density gradients, which result in low yields of variable purity. We have developed a DC enrichment platform, which uses the CMRF-44 (IgM) or CMRF-56 (IgG) monoclonal antibodies (mAb) to select BDC that express these antigens after a short overnight incubation. After culture of peripheral blood mononuclear cells (PBMC) in autologous/AB serum, biotinylated CMRF-44 was used to select DC in a single step immuno-magnetic bead procedure; this produced populations containing up to 99% CMRF-44(+) cells, including up to 67% CMRF-44(+) CD14(-) CD19(-) DC, from an initial starting population of approximately 0.5%. We observed consistent differences in the purities obtained from individual donors with a mean of 54% CMRF-44(+) cells (range 19-99%). Similar results were obtained using biotinylated CMRF-56 mAb, an antibody identifying a comparable population in cultured PBMC. We recovered an average of 54% and 66% of the available BDC in separations performed with the CMRF-44 and CMRF-56 mAb, respectively. The reproducibility of the procedure and the ability to perform it in a closed sterile system makes it suitable for clinical use. Larger scale preparations starting from apheresis derived PBMC will produce sufficient BDC for immunotherapy protocols. The purified BDC elicited strong allogeneic mixed leukocyte reactions and HLA classes II- and I-restricted antigen-specific primary immune responses. 相似文献
32.
Myriam Polette Christine Gilles Sophie de Bentzmann Dieter Gruenert Jean-Marie Tournier Philippe Birembaut 《Clinical & experimental metastasis》1998,16(2):105-112
The acquisition of a metastatic phenotype by epithelial cells implicates a series of changes altering their differentiation, their overall behavior and morphology. In the present study, we have examined the relationships between the cellular morphology, E-cadherin expression, matrix metalloproteinases expression and in vitro invasive properties in two human bronchial immortalized cell lines. The (16HBE14o-) cell line which did not show any invasive abilities in the Boyden chamber assay displayed a typical epithelial morphology in monolayer, expressed high levels of E-cadherin and synthesized neither MMP-2 and MT1-MMP nor vimentin. In contrast, the BZR cell line which was highly invasive displayed a more elongated phenotype in monolayer, did not produce E-cadherin but expressed vimentin, MMP-2 and MT1-MMP. Our data therefore suggest that the metastatic progression of broncho-pulmonary cancer cells results in a cellular dedifferentiation and the gain of some mesenchymal attributes (loss of E-cadherin and expression of vimentin) associated with enhanced degradative properties (expression of metalloproteinases).© Rapid Science 1998 相似文献
33.
Evaluation of the polymorphisms associated with tandem repeats for Pseudomonas aeruginosa strain typing
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We report on the development of a scheme for the typing of Pseudomonas aeruginosa, multiple-locus variable number of tandem repeat (VNTR) analysis (MLVA). We first evaluated the polymorphisms of 201 tandem repeat loci selected from more than 3,000 such sequences present in strain PAO1 with a test collection of 12 genotypically distinct clinical strains. Seven VNTR loci which can be easily scored with the technology used here were identified and used to genotype a collection of 89 clinical isolates that had previously been classified into 46 ribotypes, including 2 widespread ribotypes. Seventy-one different MLVA genotypes could be distinguished. With only two exceptions, strains with identical ribotypes were grouped together upon cluster analysis of the MLVA data. The 27 isolates with the most frequent ribotype were divided into 14 MLVA types, and the 18 isolates with the second most frequent ribotype were divided into 15 MLVA types. Analysis of a subset of 17 strains belonging to the major ribotype by pulsed-field gel electrophoresis with the enzyme SpeI distinguished seven types, identical to the number of MLVA types in this subset. Our data show that MLVA typing of P. aeruginosa based on the first set of loci has a high discriminatory power. Because MLVA is highly reproducible and easily portable among laboratories, it represents a very promising tool for the molecular surveillance of P. aeruginosa. A free, online strain identification service based on the genotyping data produced herein has been developed. 相似文献
34.
35.
Monfraix S Bayat S Porra L Berruyer G Nemoz C Thomlinson W Suortti P Sovijärvi AR 《Physics in medicine and biology》2005,50(1):1-11
The aim of this study was to assess the feasibility of a novel respiration-gated spiral synchrotron radiation computed tomography (SRCT) technique for direct quantification of absolute regional lung volumes, using stable xenon (Xe) gas as an inhaled indicator. Spiral SRCT with K-edge subtraction using two monochromatic x-ray beams was used to visualize and directly quantify inhaled Xe concentrations and airspace volumes in three-dimensional (3D) reconstructed lung images. Volume measurements were validated using a hollow Xe-filled phantom. Spiral images spanning 49 mm in lung height were acquired following 60 breaths of an 80% Xe-20% O2 gas mixture, in two anaesthetized and mechanically ventilated rabbits at baseline and after histamine aerosol inhalation. Volumetric images of 20 mm lung sections were obtained at functional residual capacity (FRC) and at end-inspiration. 3D images showed large patchy filling defects in peripheral airways and alveoli following histamine provocation. Local specific lung compliance was calculated based on FRC/end-inspiration images in normal lung. This study demonstrates spiral SRCT as a new technique for direct determination of regional lung volume, offering possibilities for non-invasive investigation of regional lung function and mechanics, with a uniquely high spatial resolution. An example of non-uniform volume distribution in rabbit lung following histamine inhalation is presented. 相似文献
36.
Hiroki Kurahashi Kenzo Akagi Ikuo Yana Thomas Melot Olivier Delattre Gilles Thomas Shintaro Okada Shin-ichiro Takai Isamu Nishisho 《Journal of human genetics》1994,39(2):243-248
Summary Eight cosmid clones were regionally assigned to small subregions of chromosome 22 by hybridization with a total of 22 somatic cell hybrids. One cosmid was localized to the proximal part of 22q which contained the region commonly deleted in the DiGeorge syndrome. Seven cosmids showing restriction fragment length polymorphisms were localized to the telomeric region distal to the MB locus, which was reported to be frequently deleted in sporadic meningioma. These cosmids, when finely mapped and ordered, are considered useful for the identification of genetic alterations on this chromosome arm. 相似文献
37.
Bordetella pertussis Filamentous Hemagglutinin Enhances the Immunogenicity of Liposome-Delivered Antigen Administered Intranasally 总被引:1,自引:0,他引:1
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Odile Poulain-Godefroy Nathalie Mielcarek Nathalie Ivanoff Franck Remou Anne-Marie Schacht Nigel Phillips Camille Locht Andr Capron Gilles Riveau 《Infection and immunity》1998,66(4):1764-1767
In an attempt to increase the immunogenicity of mucosally delivered antigens, we incorporated the Bordetella pertussis filamentous hemagglutinin (FHA) adhesin into liposomes containing the glutathione S-transferase of Schistosoma mansoni (Sm28GST) as a model antigen. Outbred mice immunized twice intranasally with liposomes containing a constant suboptimal dose of Sm28GST and increasing doses of FHA produced anti-Sm28GST antibodies in a FHA dose-dependent manner. The addition of 3 μg of FHA to the liposomes induced more than 10-fold-higher anti-Sm28GST antibody titers, compared to those induced by liposomes without FHA. The presence of FHA did not alter the nature of the humoral immune response, and the sera contained anti-Sm28GST immunoglobulin G1 (IgG1), IgG2a, and IgG2b. However, anti-Sm28GST IgA was only detected when at least 3 μg of FHA was added to the preparation. These results show a promising potential for FHA to enhance the immunogenicity of mucosally administered antigens incorporated into liposomes. 相似文献
38.
39.
Retinoblastoma and p53 gene product expression in breast carcinoma: Immunohistochemical analysis and clinicopathologic correlation 总被引:9,自引:0,他引:9
Michel Trudel MD Lois Mulligan PhD Webster Cavenee PhD Richard Margolese MD Jean Ct MD Gilles Garipy MD 《Human pathology》1992,23(12):1388-1394
We examined 100 breast cancers for retinoblastoma (Rb) and p53 protein expression by immunohistochemistry using the PMG3.245 and PAb 1801 antibodies. We assessed percentages of reactive cells and their intensity, as well as staining patterns. The results were correlated with neu protein reactivity and a panel of variables, including age, tumor size and type, nuclear grade, estrogen receptor/progesterone receptor content, and lymph node status. Retinoblastoma protein negativity, either partial or complete, was noted in 47% of cases. Surprisingly, a relatively stronger Rb reaction was seen in some high nuclear grade tumors. p53 positivity was found in 23% of cases and was a significant predictor of Rb loss. p53 also was correlated with poorly differentiated (nuclear grade III) neoplasms and neu expression but not with negative ER status. Tissue distribution profiles for Rb-negative and p53-positive cells were variable in this series, with both uniform and heterogeneous patterns observed. This suggests that Rb and p53 alterations may represent early or late events in transformation. Our findings further implicate Rb and p53 derangements in mammary oncogenesis. 相似文献
40.
Batard T Didierlaurent A Chabre H Mothes N Bussières L Bohle B Couret MN Ball T Lemoine P Focks Tejkl M Chenal A Clément G Dupont F Valent P Krauth MT André C Valenta R Moingeon P 《International archives of allergy and immunology》2005,136(3):239-249
BACKGROUND: We describe the production in Escherichia coli as a recombinant protein of clinical grade wild-type Bet v 1a (rBet v 1a), to be used as a candidate vaccine against birch pollen allergy. METHODS: This recombinant protein was purified by hydrophobic interaction and ion exchange chromatography and characterized by SDS-PAGE, immunoprint and circular dichroism in parallel with natural Bet v 1 (nBet v 1) purified from a birch pollen extract. We also compared rBet v 1 and nBet v 1 for their capacity to induce histamine release from basophils and to stimulate T lymphocyte proliferation. RESULTS: rBet v 1a appears in SDS-PAGE as an 18-kDa monomeric protein, whereas purified nBet v 1 comprises a mixture of isoforms (resolving as three distinct bands and six spots after 1-dimensional and 2-dimensional electrophoresis, respectively). Both recombinant and natural purified Bet v 1 molecules are recognized by IgE from birch pollen-allergic patients as well as anti-Bet v 1 murine monoclonal antibodies, suggesting that the recombinant protein is correctly folded in a native configuration. Circular dichroism analysis confirmed that the two Bet v 1 molecules exhibit similar 3-dimensional structures, even if rBet v 1a appears more compact and stable in thermodenaturation/renaturation experiments. Both rBet v 1 and nBet v 1 induce the degranulation of sensitized basophils and proliferation of Bet v 1-specific T lymphocytes in a similar manner. CONCLUSIONS: On the basis of these structural and biological properties, rBet v 1a is a valid candidate vaccine against birch pollen allergy, currently evaluated in humans. 相似文献