Search results for "Flow Cytometry"
showing 10 items of 814 documents
Systemic Immune Responses in Alzheimer's Disease: In Vitro Mononuclear Cell Activation and Cytokine Production
2010
To investigate the systemic signs of immune-inflammatory responses in Alzheimer's disease (AD), in the present study we have analyzed blood lymphocyte subsets and the expression of activation markers on peripheral blood mononuclear cells (PBMCs) from AD patients and age-matched healthy controls (HC) activated in vitro by recombinant amyloid-beta peptide (rAbeta42). Our study of AD lymphocyte subpopulations confirms the already described decrease of the absolute number and percentage of B cells when compared to HC lymphocytes, whereas the other subsets are not significantly different in patients and controls. We report the increased expression of the activation marker CD69 and of the chemoki…
Analysis of Mycobacterium tuberculosis-Specific CD8 T-Cells in Patients with Active Tuberculosis and in Individuals with Latent Infection
2009
CD8 T-cells contribute to control of Mycobacterium tuberculosis infection, but little is known about the quality of the CD8 T-cell response in subjects with latent infection and in patients with active tuberculosis disease. CD8 T-cells recognizing epitopes from 6 different proteins of Mycobacterium tuberculosis were detected by tetramer staining. Intracellular cytokines staining for specific production of IFN-gamma and IL-2 was performed, complemented by phenotyping of memory markers on antigen-specific CD8 T-cells. The ex-vivo frequencies of tetramer-specific CD8 T-cells in tuberculous patients before therapy were lower than in subjects with latent infection, but increased at four months a…
Old and new immunophenotypic markers in multiple myeloma for discrimination of responding and relapsing patients: The importance of "normal" residual…
2014
Background Multiple myeloma is an incurable disease characterized by proliferation of clonal malignant plasma cells (CPCs), which can be immunophenotypically distinguished from polyclonal plasma cells (PPCs) by multiparameter flow cytometry (MFC). The utility of PPCs analysis in detecting prognostic and predictive information is still a matter of debate. Methods: we tested the ability of 11 MFC markers in detecting differences in the immunophenotype of CPCs and PPCs among patients in various disease stages; we verified if these markers could be associated with disease stage/response to therapy despite the role of clinical parameters. Results: significant changes in the expression of markers…
Global and gene-specific histone modification profiles of mouse multipotent adult germline stem cells
2010
We previously reported the generation of multipotent adult germline stem cells (maGSCs) from spermatogonial stem cells (SSCs) isolated from adult mouse testis. In a later study, we substantiated the pluripotency of maGSCs by demonstrating their close similarity to pluripotent male embryonic stem cells (ESCs) at the epigenetic level of global and gene-specific DNA methylation. Here, we extended the comparative epigenetic analysis of maGSCs and male ESCs by investigating the second main epigenetic modification in mammals, i.e. global and gene-specific modifications of histones (H3K4 trimethylation, H3K9 acetylation, H3K9 trimethylation and H3K27 trimethylation). Using immunofluorescence stain…
CANDIDA ALBICANS INDUCES SELECTIVE DEVELOPMENT OF MACROPHAGES AND MONOCYTE DERIVED DENDRITIC CELLS BY A TLR2 DEPENDENT SIGNALLING
2011
As TLRs are expressed by haematopoietic stem and progenitor cells (HSPCs), these receptors may play a role in haematopoiesis in response to pathogens during infection. We have previously demonstrated that in in vitro defined conditions inactivated yeasts and hyphae of Candida albicans induce HSPCs proliferation and differentiation towards the myeloid lineage by a TLR2/MyD88 dependent pathway. In this work, we showed that C. albicans invasive infection with a low virulence strain results in a rapid expansion of HSPCs (identified as LKS cells: Lin(-) c-Kit(+) Sca-1(+) IL-7R alpha(-)), that reach the maximum at day 3 post-infection. This in vivo expansion of LKS cells in TLR2(-/-) mice was del…
Increased levels of Th17 cells are associated with non-neuronal acetylcholine in COPD patients.
2014
T-lymphocytes, including Th17-cells and T-cells expressing acetylcholine (ACh), are key components of systemic inflammation in chronic obstructive pulmonary disease (COPD). We investigated whether ACh promotes Th17 cells in COPD. ACh, IL-17A, IL-22, RORγt, FOXP3 expression and AChIL-17A, AChIL-22, AChRORγt coexpression was evaluated in peripheral blood mononuclear cells (PBMC) from COPD patients (n=16), healthy smokers (HS) (n=12) and healthy control subjects (HC) (n=13) (cultured for 48 h with PMA) by flow cytometry. Furthermore, we studied the effect of Tiotropium (Spiriva®) (100 nM) and Olodaterol (1nM) alone or in combination, and of hemicholinium-3 (50 μM) on AChIL-17A, AChIL-22, AChRO…
Diminished Contact Hypersensitivity Response in IL‐4 Deficient Mice at a Late Phase of the Elicitation Reaction
1997
Contact hypersensitivity (CHS) is thought to depend on the activation of T cells of Th1 and/or Tc1 type. The role of Th2/Tc2 cells in the contact allergic reaction is not clear. The aim of this study was to analyse the functional contribution of Th2/Tc2 cells in CHS using the interleukin-4 (IL-4) deficient mouse model. Interleukin-4 deficient (IL4T) and control (wt) mice were sensitized by epicutaneous application of 2,4-dinitrofluorobenzene. The ear swelling response measured 24 h after challenge was similar in IL4T and control mice. However, from 48 h onwards, ear swelling values were significantly reduced in IL4T mice. The stimulatory capacity of freshly isolated as well as 3-day culture…
Mild-stretch mechanical ventilation upregulates toll-like receptor 2 and sensitizes the lung to bacterial lipopeptide.
2011
Introduction Mechanical ventilation (MV) could prime the lung toward an inflammatory response if exposed to another insult such as bacterial invasion. The underlying mechanisms are not so far clear. Toll-like receptors (TLRs) allow the host to recognize selectively bacterial pathogens and in turn to trigger an immune response. We therefore hypothesized that MV modulates TLR2 expression and in turn modifies responsiveness to agonists such as bacterial lipopeptide (BLP). Method Both in vitro and in vivo experiments were conducted. First, TLR2 expression and protein were measured in the A549 pulmonary epithelial cell line submitted to 8-hour cyclic stretch (20% elongation; 20/minute rate). Aft…
Detection of increased tyrosine phosphorylation in murine Langerhans cells after stimulation with contact sensitizers.
1999
The signalling pathways in epidermal Langerhans cells (LC) during activation by contact sensitizers are poorly understood. Recently, we have described an increased phosphorylation of tyrosine residues in human MHC class II-positive cells in vitro following stimulation with contact sensitizers. In the study reported here the formation of phosphotyrosine (p-tyr) in murine epidermal LC upon stimulation with contact sensitizers was examined. By the use of a flow cytometric technique a significant increase in p-tyr was demonstrated in LC stimulated in vitro with the strong contact sensitizers TNCB (2,4,6-trinitro-chlorobenzene) and MCI/MI (5-chloro-2-methylisothiazolinone plus 2-methylisothiazol…
Biochemical properties of MHC class II molecules endogenously synthesized and expressed by mouse Langerhans cells
1991
The cell surface expression and biosynthesis of Langerhans cells (LC)-derived major histocompatibility complex (MHC) class II molecules from epidermal cells (EC) prepared freshly and cultured for up to 3 days was investigated. Based on the constitutive expression of MHC class II determinants by LC, a panning and magnetic bead selection procedure was employed, yielding 65% and 86% of I-A+ cells, respectively. Phenotypical and cytochemical examinations revealed that the two LC preparations were free of contaminating macrophages as well as B and T cells. Freshly prepared enriched LC were highly efficient in the stimulation of protein antigen-specific T cell clones, while LC purified from short…