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71.
Regulation of gelatinase B in human monocytic and endothelial cells by PECAM-1 ligation and its modulation by interferon-beta. 总被引:1,自引:0,他引:1
Inge Nelissen Isabelle Ronsse Jo Van Damme Ghislain Opdenakker 《Journal of leukocyte biology》2002,71(1):89-98
Platelet endothelial cell adhesion molecule-1 (PECAM-1 or CD31) and gelatinase B are coexpressed at sites of inflammation, where an intense interaction occurs between leukocytes and endothelial cells. To investigate whether a functional link exists between PECAM-1 activation and gelatinase B production, the regulatory role of PECAM-1, IFN-gamma, IFN-beta, LPS, and PMA on the production of gelatinase B (MMP-9) was studied in vitro in normal human umbilical vein endothelial cells (HUVECs), human peripheral blood mononuclear cells (PBMCs), and in a human monocytic leukemia cell line. In THP-1 cells, progelatinase B levels were slightly up-regulated by immobilized PECAM-1-specific monoclonal antibody (mAb) and soluble recombinant PECAM-1 when compared with strong induction by LPS and PMA. IFN-beta inhibited the induced and basal gelatinase B production but had no modulating effect on the expression of PECAM-1. HUVECs mainly produced progelatinase A (proMMP-2). Treatment with LPS and triggering of the endothelial cells with PECAM-1 mAb or recombinant PECAM-1 had no effect on gelatinase A or B production, whereas PMA stimulated the production of progelatinase B. IFN-beta significantly up-regulated the expression of PECAM-1 in HUVECs but did not affect gelatinase secretion. Finally, in PBMCs, progelatinase B production was increased by soluble PECAM-1 mAb, recombinant PECAM-1, LPS, and PMA, whereas IFN-beta reduced gelatinase B secretion. IFN-beta did not alter PECAM-1 expression on PBMCs. Thus, PECAM-1 and gelatinase B are differently regulated in leukocytes and endothelial cells. 相似文献
72.
Jared Liu Hsin-Wen Chang Zhi-Ming Huang Mio Nakamura Sahil Sekhon Richard Ahn Priscila Munoz-Sandoval Shrishti Bhattarai Kristen M. Beck Isabelle M. Sanchez Eric Yang Mariela Pauli Sarah T. Arron Wai-Ping Fung-Leung Ernesto Munoz Xuejun Liu Tina Bhutani Jeffrey North Wilson Liao 《The Journal of allergy and clinical immunology》2021,147(6):2370-2380
73.
74.
Linda Wittkop Daniel Commenges Isabelle Pellegrin Dominique Breilh Didier Neau Denis Lacoste Jean-Luc Pellegrin Geneviève Chêne François Dabis Rodolphe Thiébaut 《BMC medical research methodology》2008,8(1):68
Background
Principal component analysis (PCA) and partial least square (PLS) regression may be useful to summarize the HIV genotypic information. Without pre-selection each mutation presented in at least one patient is considered with a different weight. We compared these two strategies with the construction of a usual genotypic score. 相似文献75.
Anne Marie-Cardine Isabelle Maridonneau-Parini Siegmund Fischer 《European journal of immunology》1994,24(6):1255-1261
Relationships between CD45 and p56Ick have been suggested by co-immunoprecipitation of both proteins and by dephosphorylation of the p56lck regulatory site, Tyr 505, by CD45 in vitro. We investigated whether the kinase activity of p56lck is modulated in T cells triggered via CD45. We showed that incubation of Jurkat cells with a combination of two anti-CD45 monoclonal antibodies (mAb) (MC5/2 + D3/9) induced an increase in p56lck kinase activity, while a single mAb did not. Under these conditions, p56lck underwent two consecutive waves of activation. This was accompanied by internalization of the kinase and by a time-dependent increased accessibility of CD45 phosphatase at the plasma membrane. Similarly, activation and internalization of p56lck were observed using a combination of anti-CD45 (MC5/2) and anti-CD2(T112) mAb, suggesting that a functional complex consisting of CD45, CD2 and p56lck was formed upon cell triggering. Taken together, these results suggests that: (i) CD45 participates in the regulation of p56lck kinase activity in vivo and that (ii) CD45 could play a mediator role in the stimulation and endocytosis of p56lck through the CD2 pathway. 相似文献
76.
A PCR assay targeting the tpi gene was developed to detect and to genotype Giardia lamblia in human feces. Our assay was specific and discriminated between G. lamblia assemblages A and B. G. lamblia cysts isolated from human feces were also analyzed with two previously described PCR-restriction fragment length polymorphism (RFLP) assays, which are based on the detection of tpi or gdh genes. These RFLP analyses distinguished groups I and II within assemblage A or groups III and IV within assemblage B. Among 26 fecal samples from patients with sporadic giardiasis diagnosed by hospital laboratories, the tpi gene was amplified from 25 (96%) with our PCR assay, whereas only 21 (81%) samples were positive when the gdh gene was targeted. Of the 25 positive samples, nine (36%) contained assemblage A and 16 (64%) contained assemblage B. Thus, RFLP analysis classified eight samples (32%) in assemblage A group II, eight (32%) in assemblage B group III, and five (20%) in assemblage B group IV. The group could not be specified for four samples. The tpi and gdh genes of G. lamblia assemblage B were amplified from 14 (93%) of 15 samples collected only from French soldiers coming back from the Ivory Coast. All of these contained assemblage B group III. The PCR method developed is sensitive, simple, and specific and shows that the tpi gene is well adapted for G. lamblia genotyping. 相似文献
77.
Mourra N de Chaisemartin C Goubin-Versini I Parc R Flejou JF 《Archives of pathology & laboratory medicine》2005,129(3):403-406
Malignant deciduoid mesothelioma, a rare phenotype of epithelioid mesothelioma, arises more commonly from the peritoneum of young women, but it is also reported in the pleura of elderly people. We report a case of malignant deciduoid mesothelioma that occurred in a 41-year-old woman after cesarean section and was initially misdiagnosed as pseudotumoral deciduosis. Microscopically, the tumor was entirely composed of deciduoid areas, and only scattered tumor cells were positive for calretinin and keratin 5/6. The patient died 14 months after the first operation. This observation confirms the poor prognosis of this entity and the importance of the differential diagnosis of pseudotumoral deciduosis. 相似文献
78.
Comparison of the QUANTIPLEX HIV-1 RNA 2.0 Assay with the AMPLICOR HIV-1 MONITOR 1.0 Assay for Quantitation of Levels of Human Immunodeficiency Virus Type 1 RNA in Plasma of Patients Receiving Stavudine-Didanosine Combination Therapy 总被引:1,自引:4,他引:1 下载免费PDF全文
Michel Segondy Jacques Izopet Isabelle Pellegrin Brigitte Montes Beatrice Dumon Christophe Pasquier Martine Peeters Herve J. A. Fleury Jacqueline Puel Jacques Reynes 《Journal of clinical microbiology》1998,36(11):3392-3395
We compared the QUANTIPLEX HIV-1 RNA 2.0 assay with the AMPLICOR HIV-1 MONITOR 1.0 assay for quantitation of human immunodeficiency virus type 1 (HIV-1) RNA in plasma in the Stadi trail, which evaluated a stavudine plus didanosine combination therapy in 52 patients. HIV-1 RNA baseline values measured with AMPLICOR HIV-1 MONITOR 1.0 were significantly higher than those measured with QUANTIPLEX HIV-1 RNA 2.0, and decreases in HIV-1 RNA levels from baseline were also found to be significantly higher when measured with the AMPLICOR HIV-1 MONITOR 1.0 assay. The frequency of HIV-1 RNA levels below the lower limit of quantitation was significantly higher with QUANTIPLEX HIV-1 RNA 2.0 than with AMPLICOR HIV-1 MONITOR 1.0. Reanalysis of these results by an ultrasensitive procedure of AMPLICOR HIV-1 MONITOR 1.0 or by a modified version of the test that included additional primers adapted for non-B HIV-1 clades yielded greater differences between the QUANTIPLEX HIV-1 RNA 2.0 assay and the AMPLICOR HIV-1 MONITOR 1.0 assay. Our results indicate that a valid comparison of the virological efficacies obtained with different antiretroviral drug regimens requires the use of the same viral load quantitation procedure; further standardization between the different HIV-1 RNA quantitation kits is therefore needed. 相似文献
79.
Philippe Hup Cline Rouveirol Isabel Brito Pierre Neuvial Philippe La Rosa Eric Viara Nicolas Stransky Gaëlle Pierron Elodie Mani Caroline Brennetot Isabelle Jannoueix Nadge Gruel Alain Aurias Olivier Delattre Franois Radvanyi Emmanuel Barillot 《European journal of medical genetics》2005,48(4):467-468
80.
Galectin-1 is overexpressed in nasal polyps under budesonide and inhibits eosinophil migration 总被引:2,自引:0,他引:2
Delbrouck C Doyen I Belot N Decaestecker C Ghanooni R de Lavareille A Kaltner H Choufani G Danguy A Vandenhoven G Gabius HJ Hassid S Kiss R 《Laboratory investigation; a journal of technical methods and pathology》2002,82(2):147-158
Because of the importance of galectins for various cellular activities, the influence of the glucocorticoid budesonide on the level of expression of galectins-1 and -3 was investigated in human nasal polyposis. Ten nasal polyps obtained from surgical resection were maintained for 24 hours in the presence of various concentrations of budesonide. As quantitatively demonstrated by means of computer-assisted microscopy, 250 ng/ml (the highest dose tested) induced a pronounced increase of galectin-1 expression. This feature was observed in nasal polyps from allergic patients but not in those from nonallergic patients. Since eosinophils represent the main inflammatory cell population in nasal polyps, we investigated the effect of galectin-1 on their migration levels by means of quantitative phase-contrast computer-assisted videomicroscopy. Our results show that galectin-1 (coated on plastic supports) markedly reduced the migration levels of eosinophils in comparison to P-selectin. On the cellular level, marked modifications in the polymerization/depolymerization dynamics of the actin cytoskeleton (as revealed by means of computer-assisted fluorescence microscopy) and, to a much lesser extent, an increase in the adhesiveness of eosinophils to tested substrata were detectable. The present study therefore reveals a new galectin-1-mediated mechanism of action for glucocorticoid-mediated anti-inflammatory effects. 相似文献