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Surface Marker Expression (surface + marker_expression)
Selected AbstractsExpression of Integrin Receptors on Peripheral Lymphocytes: Correlation with Endometrial Receptivity1AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 3 2001VENKATA RAMI K. REDDY PROBLEM: To investigate the expression of integrin (ITG) cell adhesion molecules on peripheral blood lymphocytes (PBL) and their correlation with endometrial cell ITG expression in fertile and infertile women during peak uterine receptive period (day 19/20). METHOD OF STUDY: Surface marker expression and quantification of ,6, ,4 and ,3 ITG subunits was done by immunohistochemistry, indirect immunofluroscence and cell-enzyme-linked immunosorbent assay methods using endometrial cells and PBL obtained from fertile and infertile (unexplained infertility) women. RESULTS: The expression of ITGs was significantly (P<0.001) decreased in the endometrial cells of infertile women compared to normal fertile women. These results correlated well with the data obtained using PBL-ITG expression. CONCLUSIONS: If these preliminary data are consistent in a larger group of patients, the expression of ,4 and ,3-ITG subunits on PBL may be used as clinical markers to assess endometrial receptivity in infertile women. Moreover, frequent blood sampling is advantageous over repeated endometrial biopsies as the former approach is easier, non-traumatic and avoids intra-uterine infections. [source] Stem cells: A minireviewJOURNAL OF CELLULAR BIOCHEMISTRY, Issue S38 2002Kathyjo A. Jackson Abstract The identification of adult-derived stem cells which maintain plasticity throughout the course of a lifetime, has transformed the field of stem cell biology. Bone marrow derived hematopoietic stem cells (HSC) are the most well-characterized population of these multipotential cells. First identified for their ability to reconstitute blood lineages and rescue lethally irradiated hosts, these cells have also been shown to differentiate and integrate into skeletal muscle, cardiac myocytes, vascular endothelium, liver, and brain tissue. Various populations of HSC are being studied, exploiting cell surface marker expression, such as Sca-1, c-kit, CD34, and lin,; as well as the ability to efflux the vital dye Hoecsht 33342. Detection of engrafted donor derived cells into various tissue types in vivo is a laborious process and may involve detection of ,-galactosidase via colorimetric reaction or antibody labeling or green fluorescent protein (GFP) via fluorescence microscopy, as well as in situ hybridization to detect the Y-chromosome. Using these techniques, the search has begun for tissue specific stem cells capable of host tissue regeneration, self renewal, and transdifferentiation. Caution is urged when interpreting these types of experiments because although they are stimulating, limitations of the technologies may provide misleading results. J. Cell. Biochem. Suppl. 38: 1,6, 2002. © 2002 Wiley-Liss, Inc. [source] Cyclic acetal hydroxyapatite composites and endogenous osteogenic gene expression of rat marrow stromal cellsJOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 6 2010Minal Patel Abstract In this study, bone marrow stromal cells (BMSCs) were differentiated on cyclic acetal composites containing hydroxyapatite (HA) particles (110 or 550 nm). These composites were evaluated for their role in influencing osteogenic signalling by encapsulated BMSCs. While a number of factors exert influence on osteogenic signalling during the production of an osteogenic matrix, we hypothesize that HA particles may upregulate bone growth factor expression due to enhanced BMSC adhesion. To this end, fluorescence-activated cell sorting (FACS) analysis was performed for the evaluation of BMSC surface marker expression after culture on two-dimensional (2D) cyclic acetal/HA composites. Three-dimensional (3D) composites were then fabricated by incorporating 110 or 550 nm HA particles at 5, 10 and 50 ng/ml concentrations. Bone growth factor molecules (TGF,1, FGF-2 and PDGFa), bone biomarker molecules (ALP, OC, OPN and OCN) and extracellular matrix-related molecules (FN, MMP-13, Dmp1 and aggrecan) were selected for evaluation of osteogenic signalling mechanisms when in presence of these composites. FACS results at day 0 demonstrated that BMSCs were a heterogeneous population with a small percentage of cells staining positive for CD29, CD90 and CD51/61, while staining negative for CD34 and CD45. At day 3, a significant enrichment of cells staining strongly for CD29, CD90 and CD51/61 was achieved. Gene expression patterns for bone growth factors and extracellular matrix molecules were found to be largely dependent upon the size of HA particles. Bone marker molecules, except OCN, had unaltered expression patterns in response to the varied size of HA particles. Overall, the results indicate that larger-sized HA particles upregulate PDGF and these groups were also associated with the most significant increase in osteodifferentiation markers, particularly ALP. Our results suggest that endogenous signalling is dependent upon material properties. Furthermore, we propose that studying gene expression patterns induced by the surrounding biomaterials environment is a fundamental step in the creation of engineered tissues. Copyright © 2010 John Wiley & Sons, Ltd. [source] Evidence of in vivo basophil activation in chronic idiopathic urticariaCLINICAL & EXPERIMENTAL ALLERGY, Issue 6 2006K. Vasagar Summary Background Approximately 40% of chronic idiopathic urticaria (CIU) subjects have autoantibodies to either Fc,RI, or IgE. The effect of such autoantibodies on circulating basophil activation status is unknown. Objective The expression of cell surface activation markers on basophils from CIU, non-allergic, and allergic subjects were compared. Further, the relationship between marker expression and serum factors reported in CIU, such as histamine-releasing activity (HRA) and immunoreactivity to Fc,RI, were examined. Methods Peripheral blood was obtained from CIU, allergic, and non-allergic donors and fractionated by density gradients. Enriched basophils (1,12%) were analysed by flow cytometry for expression of activation markers including CD63, CD69, and CD203c. Dilutions of serum (5,50%) were analysed for HRA on basophils from a normal donor. Serum was tested for immunoreactivity by western blotting to a standard cell lysate prepared from an RBL-SX38 cell line transfected with human Fc,RI,. Results CIU subjects (n=9) and allergic subjects (n=8) exhibited enhanced expression of CD63 and CD69, as compared with non-allergic subjects (n=7); however, no difference was seen among groups for CD203c expression. Five CIU and two non-allergic subjects had evidence of significant serum HRA (>20%), whereas two CIU, two allergic, and three non-allergic subjects had evidence of serum immunoreactivity to Fc,RI,. Serum HRA and serum immunoreactivity to Fc,RI, were not associated with enhanced surface marker expression. Conclusion Basophil activation marker expression is increased in CIU subjects and is not associated with serum factors. In addition, serum HRA and Fc,RI, immunoreactivity are not unique to CIU, or related to enhanced circulating basophil marker expression. [source] CD4+ CD25+ transforming growth factor-,-producing T cells are present in the lung in murine tuberculosis and may regulate the host inflammatory response,CLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 3 2007C. M. Mason Summary CD4+ CD25+ regulatory T cells produce the anti-inflammatory cytokines transforming growth factor (TGF)-, or interleukin (IL)-10. Regulatory T cells have been recognized to suppress autoimmunity and promote self-tolerance. These cells may also facilitate pathogen persistence by down-regulating the host defence response during infection with Mycobacterium tuberculosis. We evaluated TGF-,+ and IL-10+ lung CD4+ CD25+ T cells in a murine model of M. tuberculosis. BALB/c mice were infected with ,50 colony-forming units of M. tuberculosis H37Rv intratracheally. At serial times post-infection, lung cells were analysed for surface marker expression (CD3, CD4, CD25) and intracellular IL-10, TGF-,, and interferon (IFN)-, production (following stimulation in vitro with anti-CD3 and anti-CD28 antibodies). CD4+ lung lymphocytes were also selected positively after lung digestion, and stimulated in vitro for 48 h with anti-CD3 and anti-CD28 antibodies in the absence and presence of anti-TGF-, antibody, anti-IL-10 antibody or rmTGF-, soluble receptor II/human Fc chimera (TGF,srII). Supernatants were assayed for elicited IFN-, and IL-2. Fluorescence activated cell sorter analyses showed that TGF-,- and IL-10-producing CD4+ CD25+ T cells are present in the lungs of infected mice. Neutralization of TGF-, and IL-10 each resulted in increases in elicited IFN-,, with the greatest effect seen when TGF,srII was used. Elicited IL-2 was not affected significantly by TGF-, neutralization. These results confirm the presence of CD4+ CD25+ TGF-,+ T cells in murine pulmonary tuberculosis, and support the possibility that TGF-, may contribute to down-regulation of the host response. [source] Respiratory syncytial virus and neutrophil activationCLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 3 2005E. L. Bataki Summary Respiratory syncytial virus infects almost all children by 2 years of age. Neutrophils are the predominant airway leucocytes in RSV bronchiolitis and they are activated in the presence of infection. However it is not clear whether RSV can directly signal to activate neutrophil cytotoxic function. To investigate this we have used a preparation of RSV washed using a new centrifugal diafiltration method to rapidly remove inflammatory molecules produced by the epithelial cells used to propagate the RSV stock. Human neutrophils were isolated from peripheral blood and activated with either the unwashed crude RSV preparations or the purified intact RSV. Neutrophils were also challenged with purified RSV G-glycoprotein. The effect of challenging human neutrophils with these preparations of intact RSV, or the RSV G-glycoprotein, was assessed by measuring the cell surface expression of CD11b and CD18b, the phagocytic oxidative burst, and intracellular release of calcium pools. Neutrophils challenged with the washed RSV exhibited significantly lower activation of surface marker expression (P < 0·001) and oxidative burst (P < 0·001) than those challenged with unwashed virus or with virus free supernatant. There was no increase in intracellular calcium release on exposure to the washed RSV. Purified G glycoprotein did not stimulate neutrophils, whilst the use of a blocking antibody to the F protein did not prevent unwashed RSV from activating cytotoxic responses. These results suggest that neutrophils have no innate signalling system that recognizes RSV but they are activated at sites of RSV infection as a result of the cytokines and inflammatory molecules released by virally infected cells. [source] | ||||||||||