Search results for "Degranulation"
showing 10 items of 81 documents
Myeloid-Derived Suppressor Cells Specifically Suppress IFN-γ Production and Antitumor Cytotoxic Activity of Vδ2 T Cells.
2018
γδ T cells represent less than 5% of circulating T cells; they exert a potent cytotoxic function against tumor or infected cells and secrete cytokines like conventional αβ T cells. As αβ T cells γδ T cells reside in the typical T cell compartments (the lymph nodes and spleen), but are more widely distributed in tissues throughout the body. For these reasons, some investigators are exploring the possibility of immunotherapies aimed to expand and activate Vδ2 T cells, or using them as Chimeric Antigen Receptor carriers. However, the role of immunosuppressive microenvironment on Vδ2 T cells during infections and cancers has not been completely elucidated. In particular, the effects of myeloid-…
Mast cells as initiators of immunity and host defense
2001
Until recently, mast cells have been viewed primarily as harmful because of their key role as effector cells of allergic and potentially lethal anaphylactic reactions. Their contribution to human health appeared instead to be limited to the elimination of parasites. There is, however, growing evidence for additional beneficial functions of mast cells, particularly regarding the initiation of acquired immune reactions. Thus, mast cells can phagocytize diverse particles, take up antigens, and express a number of receptors, particularly MHC class I and II antigens, ICAM-1 and -3, CD43, CD80, CD86 and CD40L which allow them to interact with T and B lymphocytes. They can also secrete numerous cy…
Lung CD11c+ cells from mice deficient in Epstein-Barr virus-induced gene 3 (EBI-3) prevent airway hyper-responsiveness in experimental asthma
2007
Epstein-Barr virus-induced gene (EBI)-3 codes for a soluble type 1 cytokine receptor homologous to the p40 subunit of IL-12 that is expressed by antigen-presenting cells following activation. Here, we analyzed the functional role of EBI-3 in a murine model of asthma associated with airway hyper-responsiveness (AHR) in ovalbumin-sensitized mice. Upon allergen challenge, EBI-3-/- mice showed less severe AHR, decreased numbers and degranulation of eosinophils and a significantly reduced number of VCAM-1+ cells in the lungs as compared to wild-type littermates. We thus analyzed lung CD11c+ cells before and after allergen challenge in these mice and found that before allergen challenge, lung CD1…
Comparison of the effects of salmeterol and salbutamol on clinical activity and eosinophil cationic protein serum levels during the pollen season in …
1995
In atopic asthma there is strong evidence of eosinophils playing an active role in pathogenesis. Some investigations demonstrated that eosinophil cationic protein (ECP) serum levels increased in atopic patients with asthma during pollen season.The aim of the study was to evaluate the effects of short-term (1 week) beta 2-agonist treatment on lung function and eosinophil activity in asthmatic patients.We used an open, randomized, cross-over design to compare the effects of salbutamol (200 micrograms q.i.d.) and salmeterol (50 micrograms b.i.d.) on peak expiratory flow rate (PEFR), blood eosinophil count and serum levels of ECP as a measure of eosinophil activity in 20 mild atopic asthmatics.…
Use of a comprehensive diagnostic algorithm for Anisakis allergy in a high seroprevalence Mediterranean setting
2020
Summary Background.Diagnosis of anisakis allergy (AA) is based on the skin prick test (SPT) and specific IgE (sIgE) determination. Anyway, false positivity cases are due to cross reactivity with numerous allergens. The aim of the study was to evaluate the reliability of a comprehensive diagnostic algorithm for the AA. Methods.An observational study was conducted on a sample of consecutive subjects accessing the allergology outpatient ambulatories of two hospitals located in Western Sicily. All the recruited outpatients were tested by Skin Prick Test performed using anisakis extracts by ALK-Abello (Madrid, Spain). Specific IgE dosage for anisakis extracts was then performed by using ImmunoCA…
Pentoxifylline Inhibits Vγ9/Vδ2 T Lymphocyte Activation of Patients with Active Behçet's Disease in Vitro
2007
The aim of this study is to evaluate the in vitro effect of pentoxifylline (PTX) on T Vgamma9/Vdelta2 lymphocyte function in Behçets disease (BD). We investigated the effect of PTX on Vgamma9/Vdelta2 T cell expansion and expression of TNFRII receptor and perforin content before and after PTX addition by means of FACS analysis lymphocyte cultures from patients with active and inactive BD and healthy subjects. The addition of PTX at a concentration of 1 mg/ml determined a significant inhibition of cell expansion, a down regulation of TNF receptor expression and inhibited the PMA-induced degranulation of perforin. Taken together these data indicate that PTX is capable of interfering with Vgamm…
Accumulation of dysfunctional effector CD8+T cells in the liver of patients with chronic HCV infection
2005
Background/Aims Hepatitis C virus (HCV) causes a chronic infection that can lead to fibrosis and carcinoma. Immune responses mediated by cytotoxic T lymphocytes (CTLs) could be involved in viral clearance or persistence, and therefore in determining the course of the disease. Methods Intrahepatic and peripheral blood CD8+T cells were obtained from 32 HCV-chronically infected patients and analysed by flow-cytometry for surface markers of differentiation, IFNγ and TNFα production, degranulation capacity and perforin content, after CD3 triggering. Results were compared with those obtained from 13 patients with a non-viral liver disease. Results Intrahepatic CD8+T cells of HCV-infected patients…
Reduction of plasma granzyme A correlates with severity of sepsis in burn patients.
2009
The risk of mortality is high in burn patients and correlates with age, burn area extent, and sepsis. Immunosuppression has been reported to occur after severe burn. Cytotoxic cells possess specialized granules containing perforin and a group of serine proteases (granzymes). Granzyme A is a serine protease constitutively expressed by gammadelta and NK cells, in agreement with their functional cytolytic potential. In vitro studies have shown that GrA may be released extracellularly during cytotoxic cell degranulation, indicating the activation of cytotoxic cells. The aim of our study was to determine plasma GrA activity in burned patients and to verify if decreased GrA levels were associated…
Proteomic Profiling of Colon Cancer Tissues: Discovery of New Candidate Biomarkers
2020
Colon cancer is an aggressive tumor form with a poor prognosis. This study reports a comparative proteomic analysis performed by using two-dimensional differential in-gel electrophoresis (2D-DIGE) between 26 pooled colon cancer surgical tissues and adjacent non-tumoral tissues, to identify potential target proteins correlated with carcinogenesis. The DAVID functional classification tool revealed that most of the differentially regulated proteins, acting both intracellularly and extracellularly, concur across multiple cancer steps. The identified protein classes include proteins involved in cell proliferation, apoptosis, metabolic pathways, oxidative stress, cell motility, Ras signal transdu…
Technical advance: Soluble OX40 molecule mimics regulatory T cell modulatory activity on FCεRI-dependent mast cell degranulation
2011
ABSTRACT Tregs play a central role in modulating FcɛRI-dependent MC effector functions in the course of the allergic response. Cellular interaction depends on the constitutive expression of OX40 on Tregs and the OX40L counterpart on MCs. Study of OX40L signaling on MCs is hampered by the need of a highly purified molecule, which triggers OX40L specifically. We now report that sOX40 mimics the physiological activity of Treg interaction by binding to activated MCs. When treated with sOX40, activated MCs showed decreased degranulation and Ca++ influx, whereas PLC-γ2 phosphorylation remained unaffected. Once injected into experimental animals, sOX40 not only located within the endothelium but a…